FRANK YOUNG, COMMISSIONER OF FOOD AND DRUGS, PETITIONER V.
COMMUNITY NUTRITION INSTITUTE, ET AL.

   No. 85-664

   In the Supreme Court of the United States

   October Term, 1985

   On Writ of Certiorari to the United States Court OF APPEALS FOR THE
DISTRICT OF COLUMBIA CIRCUIT

   Brief for the Petitioner

                       PARTIES TO THE PROCEEDING

   The petitioner is Frank Young, Commissioner of Food and Drugs.  The
respondents are the Community Nutrition Institute, Public Citizen, and
Linda S. Bardot.

            TABLE OF CONTENTS
   Parties to the proceeding
   Opinions below
   Jurisdiction
   Statutes and regulatory provisions involved
   Question Presented
   Statement:
      A. Introduction
      B. The statutory and regulatory framework
         1. The statutory definition of "adulterated"
            food
         2. The FDA's use of "action levels" and
            tolerances"
         3. The exemption process
      C. The proceedings below
         1. The district court's decision
         2. The court of appeals' decision
   Introduction and summary of argument
   Argument:
      The Federal Food, Drug, and Cosmetic Act
      authorizes the Commissioner of Food and Drugs to
      regulate unavoidable added poisonous or deleterious
      substances in food by means of case-by-case
      adjudication or by formal rulemaking
      A. The FDA's interpretation of 21 U.S.C. 346
         is consistent with the text, legislative history, and
         purposes of the Federal Food, Drug, and Cosmetic
         Act
         1. The FDA's construction of Section 406 gives
            effect to the interrelationship between Sections
            402(a)(1) and 406
            a. Section 406 does not render adulterated a
               food containing a required or an unavoidable
               added poisonous or deleterious substance
               in the absence of a tolerance
            b. The FDA's interpretation of Section 406
               gives effect to the role played by Section
               402(a)(1) in the overall regulatory
               scheme
         2. The FDA's construction of Section 406 is
            consistent with the role that provision plays in
            the enforcement process
            a. The Federal Food and Drugs Act of 1906
            b. The Federal Food, Drug, and Cosmetic
                  Acts of 1938
            c. The effect of Section 406
      B. The FDA's longstanding construction of the
         FDCA is entitled to substantial deference
         1. The FDA has followed an unwavering construction
            of 21 U.S.C. 342 and 346 since the
            inception of the FDCA nearly a half-century
            ago
         2. Congress has endorsed the FDA's construction
            of the FDCA in amending the Act
         3. The court of appeals' ruling hampers the
            effective enforcement of the FDCA
   Conclusion

                            OPINIONS BELOW

   The opinion of the court of appeals (Pet. App. 1a-16a) is reported
at 757 F.2d 354.  The May 1, 1985, order amending the court of
appeals' opinion (Pet. App. 17a) and the opinion of the district court
(Pet. App. 21a-34a) are unreported.

                             JURISDICTION

   The judgment of the court of appeals (Pet. App. 35a) was entered on
March 26, 1985.  A petition for rehearing was denied on May 23, 1985
(Pet. App. 18a).  By order dated August 13, 1985, Justice Brennan
extended the time within which to file a petition for a writ of
certiorari to and including October 20, 1985.  The petition was filed
on October 18, 1985, and was granted on December 9, 1985.  The
jurisdiction of this Court is invoked under 28 U.S.C. 1254(1).

             STATUTORY AND REGULATORY PROVISIONS INVOLVED

   Sections 402(a), 406, and 701(e) of the Federal Food, Drug, and
Cosmetic Act, 21 U.S.C. 342(a), 346, and 371(e), and 21 C.F.R.
509.6(b)-(c) are reproduced in an appendix to this brief. App., infra,
1a-5a.

                          QUESTION PRESENTED

   Whether the Food and Drug Administration is required to regulate
unavoidable "added" poisonous or deleterious substances in food by
means of formal rulemaking pursuant to 21 U.S.C. 342(a)(2)(A), rather
than by case-by-case adjudication pursuant to 21 U.S.C. 342(a)(1).

                               STATEMENT

   A. Introduction

   This case concerns the procedures that the Food and Drug
Administration (FDA) must employ in regulating the presence in food of
any added poisonous or deleterious substance that is required in the
production of the food or that cannot be avoided by good manufacturing
practices.  Specifically at issue here are "aflatoxins," a group of
chemically-related substances produced as natural by-products of the
growth of certain common molds on corn and other crops.  Aflatoxins
exhibit cancer-producing properties in some species of experimental
animals, and epidemiological studies on certain population groups in
Southeast Asia and Africa indicate that direct consumption of
aflatoxin-containing foods may also be associated with primary liver
cancer in humans.  J.A. 35-37, 169, 203;  Pet. App. 3a.  However,
these studies cannot identify all potential causes of the disease
(J.A. 214), and there is no direct evidence that aflatoxin causes
primary liver cancer in man.  J.A. 35, 46.  Data from the National
Center for Health Statistics on deaths due to such cancer from all
sources in the United States do not show an increased incidence in
areas where aflatoxin contamination is an annual problem.  J.A. 214,
218-221.

   Aflatoxins may contaminate foods whenever environmental conditions
are such as to favor the growth of the producing molds.  Favorable
growth conditions often exist naturally in the field where susceptible
crops are growing.  Such conditions also can be created when crops are
improperly stored.  See J.A. 207-208.  Human intervention can prevent
the problem in the latter situation, but preventative action is
largely ineffective in the case of field contamination, because the
contamination occurs before or during harvest.  Thus, complete
elimination of aflatoxin from susceptible commodities, such as corn,
cottonseed, peanuts, and tree nuts, is not currently possible.  See
J.A. 39, 43, 44, 208;  39 Fed. Reg. 42748 (1974).  Moreover, residues
of aflatoxin can appear in the edible tissues, eggs, and milk of
animals fed aflatoxin-contaminated corn, cottonseed, and other feeds,
and there is no known method for removing aflatoxin residues from such
products.  J.A. 207.  For all these reasons, the FDA has treated
aflatoxin as a poisonous or deleterious substance and has taken steps
to limit human and animal exposure to aflatoxin-tainted food to the
greatest extent feasible.  39 Fed. Reg. 42749 (1978);  J.A. 187, 207.

   Since the enactment of the Federal Food, Drug, and Cosmetic Act
(FDCA) in 1938, 21 U.S.C. 301 et seq., the Commissioner of Food and
Drugs, as the designee of the Secretary, /1/ has regulated the amount
of substances like aflatoxin principally by using publicly available
prosecutorial guidelines that the FDA terms "action levels." /2/ These
action levels announce the amount of a particular added poisonous or
deleterious substance that the FDA regards as resulting in
adulteration under Section 402(a)(1) of the FDCA, 21 U.S.C. 342(a)(1).
 Food containing such a substance in excess of the action level is
subject to an enforcement action by the United States.  In this case,
the court of appeals upset this longstanding administrative
construction of the FDCA, holding that the FDA may not proceed by
means of action levels but must instead set "tolerances" by
time-consuming and burdensome formal rulemaking procedures.

   B. The Statutory and Regulatory Framework

   1. The Statutory Definition Of "Adulterated" Food.  The FDCA
prohibits the shipment in interstate commerce of "adulterated" food.
21 U.S.C. 331.  A food is generally deemed to be "adulterated" due to
the presence of a poisonous or deleterious substance, whether it is
inherent in the food or is "added" to it, /3/ if any one of three
conditions is met.  See 21 U.S.C. 342(a)(1) and (2)(A).  /4/ First, a
food is deemed adulterated under the first clause of Section 402(a)(1)
of the FDCA, 21 U.S.C. 342(a)(1), if it contains an added poisonous or
deleterious substance "which may render it injurious to health." /5/
Second, if a substance is inherent in a food (i.e., is not "added"),
then, under the second clause of Section 402(a)(1), food containing
that substance is adulterated if the substance renders the food
"ordinarily * * * injurious to health." /6/ Third, a food is
adulterated under Section 402(a)(2)(A), 21 U.S.C. 342(a)(2)(A), if it
contains any "added poisonous or added deleterious substance * * *
which is unsafe within the meaning of" Section 406, 21 U.S.C. 346.
Aflatoxin fits within this last provision (as well as the first one);
it is not an inherent constituent of food since it is added by mold.
J.A. 34-35.

   Section 406 of the FDCA defines when a food with an added poison is
"unsafe" within the meaning of that provision.  The first clause of
Section 406 provides that any added poisonous or deleterious substance
renders the food unsafe unless its presence "is required in the
production thereof or cannot be avoided by good manufacturing
practice." Aflatoxin falls within this exception (see J.A. 187, 207),
and food containing aflatoxin is therefore not rendered "unsafe" by
this clause.  However, Section 406 goes on to state:

      "(W)hen such substance is so required or cannot be so avoided,
      the Secretary (of Health and Human Services) shall promulgate
      regulations limiting the quantity therein or thereon to such
      extent as he finds necessary for the protection of public
      health, and any quantity exceeding the limits so fixed shall
      also be deemed to be unsafe for purposes of the application of
      (Section 342(a)(2)(A)).

   Section 406 further provides that, while a regulation is in effect,
food containing such a substance is not adulterated under Section
402(a)(1).

   2. The FDA's Use Of "Action Levels" And "Tolerances." For nearly a
half-century, the FDA has construed these provisions as allowing it to
regulate substances such as aflatoxin either by exercising its
prosecutorial discretion to bring enforcement actions under Section
402(a)(1), 21 U.S.C. 342(a)(1), or by issuing regulations
("tolerances") via formal rulemaking pursuant to Sections 406 and
701(e), 21 U.S.C. 346 and 371(e).  If the FDA elects to proceed under
Section 402(a)(1), the government must establish in an enforcement
proceeding that the level of the added substance present may render
the food injurious to health.  This is the option that the FDA has
used with respect to aflatoxin, and the FDA has adopted an "action
level" to aid in the exercise of its prosecutorial discretion.  J.A.
150.  In the alternative, the FDA may promulgate a tolerance under
Section 406.  Once a tolerance is in effect, the government in an
enforcement proceeding need only establish that the tolerance has been
exceeded;  it need not adduce independent evidence that the food may
be injurious to health.  See 21 U.S.C. 342(a)(2)(A) and 346.
Therefore, the use of action levels or tolerances affects only the
government's elements of proof in an enforcement action.  In either
case, the contaminated food is subject to seizure (see 21 U.S.C. 334)
and the person responsible for shipping the contaminated food in
interstate commerce may be enjoined from causing such shipment (see 21
U.S.C. 332) and subjected to criminal sanctions (see 21 U.S.C. 333).

   The FDA considers the same factors -- i.e., those set forth in 21
U.S.C. 346 -- in setting both action levels and tolerances.  21 C.F.R.
109.6 (human food);  21 C.F.R. 509.6 (animal feed).  /7/ However, the
procedures employed in promulgating action levels differ significantly
from those required for the issuance of tolerances.  Action levels are
not considered to be subject to the notice-and-comment rulemaking
procedures of the Administrative Procedure Act.  /8/ Nonetheless, the
FDA does publish a notice in the Federal Register announcing the new
level and the availability of all the relevant data, and it invites
public comment.  See 21 C.F.R. 509.4(b)(2);  42 Fed. Reg. 52817
(1977).

   By contrast, 21 U.S.C. 346, in conjunction with 21 U.S.C. 371(e),
prescribes a formal and complicated procedure for the issuance of
regulations setting, amending, or repealing tolerances for substances
whose addition to food is required or unavoidable.  The FDA must
publish a proposed tolerance for public comment.  21 U.S.C. 371(e)(1).
 After evaluating the comments, the FDA must publish a "final order"
to which objections can be filed, along with requests for a formal
trial-type administrative hearing.  Ibid.  The filing of an objection
accompanied by an adequate request for a hearing stays the
effectiveness of the tolerance pending further notice in the Federal
Register and the hearing itself (21 U.S.C. 371(e)(2)), at which "any
interested person may be heard in person or by representative" (21
U.S.C. 371(e)(3)).  Finally, following the completion of the formal
administrative proceeding, including an initial decision by an
administrative law judge and any subsequent appeal to the Commissioner
of Food and Drugs, the FDA must issue an order setting forth "detailed
findings of fact" and establishing the tolerance.  Ibid.  Except in
emergencies, the regulation may not take effect until 90 days after
the Commissioner's decision (ibid.), which is subject to judicial
review in the court of appeals (21 U.S.C. 371(f)).  In short, 21
U.S.C. 346 and 371(e) mandate a formal rulemaking procedure properly
characterized as one of the more elaborate under which any federal
agency must operate.  See generally R. Merrill & P. Hutt, Food and
Drug Law 895-896 (1980).

   In determining whether to issue informal action levels or formal
tolerances in a particular case, the FDA takes these procedural
differences into account.  Because of the exhaustive procedures
necessary to establish a new tolerance or to modify an existing one,
the FDA generally establishes tolerances only when their lifespan is
expected to be relatively long.  Accordingly, the FDA's regulations
provide for the use of action levels in dynamic circumstances, i.e.,
when it is impracticable to set tolerances.  See 21 C.F.R. Pt. 109
(human food);  21 C.F.R. Pt. 509 (animal feed);  J.A. 21, 68.  The FDA
uses action levels rather than tolerances when the extent to which a
substance is unavoidable may change yearly, when changes in the
capabilities of good manufacturing practices are expected, or when
current toxicological data are scanty or conflicting but the results
of ongoing studies might provide significant new data or other
information that would render a tolerance obsolete.  21 C.F.R.
109.6(b)-(c), 509.6(b)-(c);  J.A. 21, 68-70.  For instance, the FDA
has used action levels to regulate the presence of aflatoxin in corn
because the level of aflatoxin in corn varies from region to region,
and within regions, from year to year.  See J.A. 223-224.  In these
circumstances, a tolerance would be outdated shortly after its
adoption.  See J.A. 68.  /9/

   3. The Exemption Process.  The FDA has recognized that in some
circumstances the public interest may justify allowing certain food
containing a substance in an amount in excess of an action level to be
marketed.  The FDA's regulations therefore allow the Commissioner to
refrain from recommending enforcement action (i.e., to grant an
"exemption") in such circumstances.  21 C.F.R. 109.8(a)(1),
509.8(a)(1).  The FDA has stated that an exemption will be granted
only where "a large amount of food is contaminated, resulting in a
substantial adverse impact on the national food supply, and all
available toxicological data indicate that no significant health
hazard is involved." 39 Fed. Reg. 42746 (1974);  J.A. 24.  An
exemption applies only to the specific parties to whom it is granted
and only to the particular food covered, and lasts only for a
specified period of time.  Ibid.

   In 1965, the FDA set an action level for aflatoxin in human food
and animal feed at 30 parts per billion (ppb).  J.A. 37.  The FDA
reduced the action level to 20 ppb in 1969, and it has since remained
at that level.  Ibid.; id. at 135, 169, 170;  Pet. App. 22a.  However,
in 1980 the levels of aflatoxin in corn harvested in several states
were unusually high.  In October and November 1980, in response to
requests from Virginia, North Carolina, and South Carolina, the FDA
temporarily increased to 100 ppb the action level for
aflatoxin-contaminated corn harvested in those states that was
intended for feeding to mature, non-lactating beef cattle, swine, or
poultry.  The agency also permitted blending (mixing) of corn
containing more than 20 ppb aflatoxin with untainted corn to achieve a
level of up to 100 ppb aflatoxin.  The FDA found that, under the terms
and conditions of the exemptions, the feed corn was safe for
consumption and that the destruction or diversion of the feed would
have resulted in a substantial adverse effect on the national food
supply.  /10/ The exemptions were conditioned upon full compliance by
the states and the affected industries with detailed control plans
designed to ensure that the terms of the exemptions were satisfied.
The FDA's decision not to recommend enforcement action was contingent
upon such full compliance.  See 46 Fed. Reg. 7447 (1981);  J.A. 24,
114-122, 131-132, 189-190, 196-197, 199-201;  Pet. App. 25a-26a.
These exemptions, which expired on January 1, 1982, gave rise to this
lawsuit.  Pet. App. 25a, 26a.

   C. The Proceedings Below

   1. The District Court's Decision.  Respondents (two public interest
groups and a consumer) brought this suit in the United States District
Court for the District of Columbia, challenging the FDA's regulation
of aflatoxin.  /11/ Respondents did not allege that the FDA's 20 ppb
action level was insufficient to protect the public health or had led
to any serious health problem, that formal tolerances were necessary
to protect the public health, or that the FDA was not adequately
enforcing the FDCA (J.A. 109-112 (complaint)).  Rather, they claimed
(1) that the FDA should be ordered to adopt a formal tolerance for
aflatoxin pursuant to Section 406, 21 U.S.C. 346, rather than to use
an informally implemented action level, (2) that the action level, in
the alternative, should be made subject to the notice-and-comment
provisions of the Administrative Procedure Act, and (3) that the 1980
exemptions to the FDA's action level were contrary to law.  J.A.
109-112 (complaint);  see also id. at 169-171, 225-226.

   The district court granted summary judgment in favor of the FDA on
all three issues (Pet. App. 21a-34a).  Recognizing that an agency's
interpretation of the statute it is responsible for administering is
entitled to substantial deference, the court ruled that the FDA's
construction of Section 406 was reasonable and that Section 406
"confers discretionary, not mandatory, authority on the agency to
establish tolerances" (Pet. App. 31a-32a (footnote omitted)).  The
court also concluded that "action levels" were general statements of
policy not requiring notice-and-comment rulemaking and that the
exemptions granted by the FDA were within the agency's discretion (id.
at 32a-34a).

   2. The Court Of Appeals' Decision.  The court of appeals reversed,
holding that "the FDA may not proceed by means of action levels rather
than tolerances" (Pet. App. 2a).  /12/ The court relied heavily on its
parsing of the second clause of Section 406, which provides that when
an added poisonous or deleterious substance is "required" or "cannot
be * * * avoided * * * the Secretary shall promulgate regulations
limiting the quantity therein or thereon to such extent as he finds
necessary for the protection of public health." The court refused to
accept (Pet. App. 6a) the FDA's interpretation of this provision,
i.e., that the Secretary is obligated to promulgate formal regulations
only "'to such extent as he finds necessary for the protection of
public health'" and may employ informal action levels in all other
circumstances.  Instead, the court found (id. at 7a) that it was
"clear from the structure of the sentence * * * that the phrase relied
upon by the Secretary simply does not modify the pivotal word 'shall'"
but, rather, "explains the standard that the Secretary is to employ in
setting the tolerance."

   The court of appeals found additional support for its
interpretation of the FDCA in an argument that suggests that most of
the nation's food supply is "adulterated" within the meaning of the
FDCA.  The court construed (Pet. App. 7a) Section 406 to mean that any
food to which an unavoidable poisonous or deleterious substance has
been added is adulterated unless "a regulation establishing a
tolerance is in effect." The court reasoned (Pet. App. 7a) that,
"(s)ince the existence of a regulation operates to render the food
legally unadulterated, the statute, in our view, plainly requires the
establishment by regulation of tolerances before aflatoxin-tainted
corn may lawfully be shipped in interstate commerce." The court
advanced no other argument to buttress its interpretation.  It found
"little guidance in the legislative history" (id. at 9a), and it did
not cite any supporting judicial authority, but instead merely
attempted to distinguish the cases upon which the FDA relied (id. at
11a-15a).

                 INTRODUCTION AND SUMMARY OF ARGUMENT

   In the prouction of food, it is often impossible to avoid the
presence of negligible quantities of added substances that may be
harmful to human health if taken in sufficient amounts.  /13/ For
nearly 50 years, the FDA, with Congress's full awareness and the
federal courts' approval, has regulated the presence of these
substances in food principally by adopting informal "action levels" --
i.e., "in-house" guidelines used by the agency to inform its broad
prosecutorial discretion (see Heckler v. Chaney, No. 83-1878 (Mar. 20,
1985)) -- and by relying on these prosecutorial guidelines in
case-by-case litigation under Section 402(a)(1) of the FDCA, 21 U.S.C.
342(a)(1).  This informal procedure has allowed the FDA to move
quickly in response to health hazards;  it has provided flexibility in
an area in which the relevant scientific data and the capabilities of
good manufacturing practices are subject to frequent and unforeseen
modification;  and it has permitted the FDA, by limiting burdensome
and lengthy formal rulemaking proceedings, to allocate its scarce
resources to activities of greater need in safeguarding the public
health.

   In this case, the court of appeals ruled that the FDA's historic
regulatory practice is -- and has been from the outset -- ultra vires.
 Relying entirely upon a literal reading of statutory language that is
ambiguous at best, and without regard for the statute's legislative
history or purposes, the court held that the FDA is powerless to
follow its settled practice because it has a mandatory duty under
Section 406, 21 U.S.C. 346, to institute formal rulemaking proceedings
to establish tolerances for added substances like aflatoxin.  That
ruling upsets the FDA's settled and successful practice and threatens
both to squander administrative resources and to impair the FDA's
ability to act expeditiously in response to changing conditions in
this vitally important area.  The court of appeals' reasoning also
suggests that much of the nation's food supply is now and will remain
"adulterated" within the meaning of the FDCA until formal regulations
setting tolerances are issued, a process that is certain to take
years, if not decades, to complete.

   These unfortunate consequences need not be suffered, because the
court of appeals' decision is plainly wrong.  The court disregarded
the well settled principle that an agency's construction of a statute
that it is entrusted to administer is entitled to substantial
deference.  Here, the FDA's construction of Section 406 is fully
consistent with the language, structure, and purposes of that and
related sections of the FDCA.  Moreover, a number of factors coalesce
to show that the FDA's interpretation of the Act is entitled to
particular deference.

   1.a. By focusing on the term "shall" in Section 406, the court of
appeals misconstrued the overall structure of the FDCA.  Section
402(a)(1) establishes the general standard of adulteration and
provides that a food is adulterated whenever an added poisonous or
deleterious substance may render the food injurious to health.
Sections 406 and 402(a)(2)(A) provide that such an added substance
automatically renders a food adulterated if the substance is not
required in food production or is not unavoidable.  Where neither
condition obtains, Sections 406 and 402(a)(2)(A) deem a food to be
adulterated only if it contains a poisonous or deleterious substance
in excess of an existing tolerance;  if no tolerance exists, a food is
adulterated only if it may cause injury under Section 402(a)(1).  The
language of Section 406 contemplates the situation in which no
tolerance is in effect by providing that "(w)hile such a regulation is
in effect * * * food (containing an added poisonous or deleterious
substance) shall not * * * be considered to be adulterated" under
Section 402(a)(1).  See Flemming v. Florida Citrus Exchange, 358 U.S.
153, 166 (1958).  In the absence of a tolerance, Section 402(a)(1)
governs.

   The court of appeals' reading of Section 406 renders Section
402(a)(1) superfluous for added poisonous or deleterious substances
that are required in food production or unavoidable.  Sections 406 and
402(a)(2)(A) ban added poisonous or deleterious substances if they are
not required or are not unavoidable.  Thus, if the absence of a
tolerance also bans such substances if they are required or are
unavoidable, the FDA would never have occasion to resort to Section
402(a)(1) to prove that a food that contains such a substance is
adulterated, despite the fact that Section 402(a)(1), like Sections
406 and 402(a)(2)(A), applies to added substances.  The FDA's
construction of Section 406, unlike the one adopted by the court of
appeals, therefore gives effect to Sections 402(a)(1) and 406 for
added substances like aflatoxin.

   b. The legislative background of Section 406 reveals that Congress
enacted this provision to empower the agency to select alternative
ways of proving that a food is adulterated.  The predecessor to the
FDCA (the Federal Food and Drugs Act of 1906) required the FDA to
prove in court in each case that a particular food posed a risk of
injury to a consumer's health.  United States v. Lexington Mill &
Elevator Co., 232 U.S. 399 (1914).  Section 406 was designed to allow
the agency to adopt legislative rules fixing precise levels of
forbidden contaminants for a broad range of added substances that, if
exceeded, automatically rendered a food adulterated.  Congress did not
intend that the FDA must promulgate tolerances to enforce the
adulteration provisions of the FDCA;  on the contrary, Congress
retained the provision of the original Federal Food and Drugs Act that
allowed the agency to prove on a case-by-case basis that a food
containing an added substance was unsafe.  Both the agency, which
drafted the original version of the FDCA, and Congress used the verbs
"shall" and "is authorized to" interchangeably throughout Congress's
consideration of the FDCA.  And no witness who testified during the
lengthy legislative consideration of the FDCA suggested that
tolerances would be the exclusive means of enforcing the food
adulteration provisions of the Act.

   2. The FDA's construction of Section 406 is entitled to special
deference for several reasons.  First, the agency played an important
role in drafting the statute.  Second, for nearly a half-century,
beginning almost immediately after passage of the FDCA, the FDA has
consistently read this section as providing the agency with the
discretion to promulgate tolerances.  Third, Congress has been made
aware of the agency's position and has done nothing to require the FDA
to alter its historic regulatory practice;  in fact, Congress relied
on the agency's views when enacting amendments to the FDCA.  Fourth,
depriving the FDA of the discretion whether to enforce the statute by
relying upon action levels and bringing enforcement actions or by
setting tolerances would hamper the agency's ability to respond
quickly to new toxicological data or changes in manufacturing
practices and would divert the agency's limited resources from matters
of greater need in the protection of the public health.

                               ARGUMENT

 THE FEDERAL FOOD, DRUG, AND COSMETIC ACT AUTHORIZES THE COMMISSIONER
OF FOOD AND DRUGS TO REGULATE UNAVOIDABLE ADDED POISONOUS OR
DELETERIOUS SUBSTANCES IN FOOD BY MEANS OF CASE-BY-CASE ADJUDICATION
OR BY FORMAL RULEMAKING

   It is a familiar and well-established principle of administrative
law and statutory construction that an agency's interpretation of a
statute that it is entrusted to administer is entitled to considerable
deference from the courts.  See, e.g., United States v. Riverside
Bayview Homes, Inc., No. 84-701 (Dec. 4, 1985), slip op. 9;  Chevron
U.S.A. Inc. v. NRDC, No. 82-1005 (June 25, 1984), slip op. 4-7.  A
court is not free to overturn the agency's interpretation simply
because the court may prefer a different one or because reasonable
persons may differ as to the statute's meaning.  Rather, so long as
the agency has reasonably sought to implement a congressional policy
rather than embark on a frolic and detour of its own, the agency's
interpretation must be upheld.  See, e.g., Riverside Bayview Homes,
slip op. 9-10, 17;  Chevron, slip op. 5-7 & nn. 11-14;  Aluminum Co.
of America v. Central Lincoln Peoples' Utility District, No. 82-1071
(June 5, 1984), slip op. 8.

   Under that standard, the FDA's contemporaneous and longstanding
interpretation of Section 406 of the Federal Food, Drug, and Cosmetic
Act, 21 U.S.C. 346, should have been sustained.  First, for the
reasons given in Point A below, in light of the structure, purposes,
and legislative history of the FDCA, it is entirely reasonable for the
FDA to construe Section 406 as discretionary, rather than mandatory.
Second, for the reasons explained in Point B below, a variety of
factors make this a particularly compelling case for affording
deference to the FDA.

 A. The FDA's Interpretation of 21 U.S.C. 346 Is Consistent With The
Text, Legislative History, And Purposes Of The Federal Food, Drug, And
Cosmetic Act

   As the court of appeals recognized, the privotal statutory
provision is the second clause of Section 406, 21 U.S.C. 346.  It
provides that when any added poisonous or deleterious substance is
"required" in the production of food or "cannot be avoided by good
manufacturing practice," the Commissioner of Food and Drugs "shall
promulgate regulations limiting the quantity therein or thereon to
such extent as he finds necessary for the protection of public
health." In the FDA's view, the phrase "to such extent as he finds
necessary for the protection of the public health" modifies the verb
"shall." So read, Section 406 provides that the agency must promulgate
regulations only if it finds that doing so is necessary to protect the
public health.  Put another way, the statute means that the FDA can
promulgate tolerances, not that the agency must do so.  See Webster's
New Collegiate Dictionary 1058 (1981) (noting these alternative
definitions of "shall").  The FDA has long interpreted this section to
mean that the agency is empowered, not required, to issue formal
tolerances to enforce the adulteration provisions of the FDCA.  See,
e.g., Trade Correspondence 136 (Mar. 7, 1940), repreinted in 1 V.
Kleinfield, C. Dunn & A. Kaplan, Federal Food, Drug, and Cosmetic Act
Judicial Record 1938-1964, at 622 (Food and Drug Law Inst. 1978).
/14/

   This Court also read the FDCA in that manner in Flemming v. Florida
Citrus Exchange, 358 U.S. 153 (1958).  There, the Court examined the
food adulteration provisions of the FDCA at issue in this case,
Sections 402(a)(1) and 406(a) of the Act, 21 U.S.C. (1952 ed.)
342(a)(1) and 346(a), in the context of their relationship to the
FDCA's color additive provisions, Sections 402(c) and 406(b), 21
U.S.C. (1952 ed.) 342(c) and 346(b).  /15/ The Court noted that
"Section 406(a) (now 406) of the Act * * * allows the Secretary to
establish tolerances for poisonous substances added to food where the
substance is 'required in the production' of the food or 'cannot be
avoided by good manufacturing practice'" (358 U.S. at 165-166
(emphasis added)) and found that "the provisions authorizing the
establishment of tolerances apply only to Section 402(a)(1) and (2)
and do not apply to Section 402(c)'s flat prohibition against the use
of uncertified colors" (358 U.S. at 166-167 (emphasis added)).  See
id. at 166 ("Section 406(a) * * * provides for the system of
tolerances").  Other courts have also concluded that Section 406
authorizes the agency to rely on either informal action levels or
formal tolerances to enforce the adulteration provisions of the FDCA.
See United States v. Boston Farm Center, Inc., 590 F.2d 149, 151 (5th
Cir. 1979);  see also Certified Color Industry Committee v. Secretary
of HEW, 236 F.2d 866, 868 (2d Cir. 1956);  United States v. Anderson
Seafoods, Inc., 447 F. Supp. 1151, 1153 n.2 (N.D. Fla. 1978), aff'd,
622 F.2d 157 (5th Cir. 1980);  United States v. 935 Cases, Etc.,
Tomato Puree, 65 F. Supp. 503, 505 (N.D. Ohio 1946);  cf. United
States v. Goodman, 486 F.2d 847 (7th Cir. 1973).  But see United
States v. Ewig Bros., 502 F.2d 715, 720 (7th Cir. 1974), cert. denied,
420 U.S. 945 (1975) (dictum).  /16/

   By contrast, the court below ruled that the Commissioner has the
nondiscretionary duty to promulgate regulations governing every added
substance before food containing the substances treated in Sections
402 and 406, 21 U.S.C. 342 and 346, may be shipped in interstate
commerce and that the FDA may not enforce the FDCA by relying upon
action levels.  The court relied heavily on the dictionary meaning of
what it termed "the critical word 'shall'" in the second clause of
Section 406 (Pet. App. 6a), which the court construed as requiring the
FDA to promulgate tolerances to exempt food containing any quantity of
any unavoidable added poisonous or deleterious substance from the
scope of that section (id. at 6a-7a).  In addition, the court
concluded that the phrase "to such extent as (the Commissioner) finds
necessary for the protection of public health" modifies the participle
"limiting," and thus affects the level of the tolerances that must be
established rather than the FDA's discretion whether to adopt a
tolerance at all.  Id. at 7a.  Accordingly, the court of appeals
concluded that, in the absence of a formal tolerance, a food is
adulterated if it contains any quantity of any substance specified in
Section 406.  Pet. App. 7a.  We submit that the reasons offered by the
court of appeals are plainly insufficient to overcome the FDA's
settled construction of the Act.

 1. The FDA's Construction Of Section 406 Gives Effect To The
Interrelationship Between Sections 402(a)(1) And 406

   Although the court of appeals properly began its analysis of the
statute by looking to its plain terms (see CPSC v. GTE Sylvania, Inc.,
447 U.S. 102, 108 (1980)), the court went astray by focusing on the
term "shall" in Section 406 to the exclusion of the statute as a
whole.  This Court has repeatedly explained that, "(i)n expounding a
statute, we must not be guided by a single sentence or member of a
sentence, but look to the provisions of the whole law, and to its
object and policy." Philbrook v. Glodgett, 421 U.S. 707, 713 (1975)
(citation omitted);  Bob Jones University v. United States, 461 U.S.
574, 586 (1983).  By fixing exclusively on one possible interpretation
of the literal meaning and placement of the term "shall" and failing
to consider the relationship between Sections 402(a)(1) and 406, the
court of appeals not only misconstrued Section 406, but also rendered
Section 402(a)(1) superfluous for added substances, like aflatoxin.

   a. Section 406 Does Not Render Adulterated A Food Containing A
Required Or An Unavoidable Added Poisonous Or Deleterious Substance In
The Absence Of A Tolerance.  The starting point for analysis of the
food adulteration provisions of the FDCA is Section 402, 21 U.S.C.
342, which establishes the general definition of "adulteration."
Section 402 covers food containing either an added or an inherent
substance.  Since aflatoxin is an added substance, only that portion
of Section 402 applicable to added substances is directly relevant in
this case.

   Food containing an added poisonous or deleterious substance is
deemed to be adulterated under Section 402 in two different
situations.  /17/ First, under Section 402(a)(1), the food is
adulterated if the substance is present in a sufficient quantity that
the food may be injurious to health.  21 U.S.C. 342(a)(1).  This
section has been part of the federal food regulatory scheme since
1906, and it establishes a general, qualitative standard.  Second,
under Section 402(a)(2)(A), the food is adulterated if it is "unsafe"
within the meaning of Section 406, 21 U.S.C. 346.  21 U.S.C.
342(a)(2)(A).  Section 406 establishes a quantitative standard of
adulteration.

   The first sentence of Section 406 consists of two separate clauses,
each of which covers a different situation.  Under the opening clause
of Section 406, the addition of a poisonous or deleterious substance
to a food renders the food unsafe (and thus adulterated) if the
substance is not required in the production of the food or is
avoidable.  The next clause of Section 406 addresses the alternative
situation in which the addition of a poisonous or deleterious
substance to food is required in food production or is unavoidable.
In that circumstance, Section 406 renders a food unsafe if a tolerance
is in effect and the food contains the added contaminant in an amount
that exceeds the tolerance.  Put another way, Section 406 bans the
addition to food of a poisonous or deleterious substance when that
substance is not required in food production or is not unavoidable.
However, when the addition of a poisonous or deleterious substance to
food is required in food production or is unavoidable, Section 406
does not automatically render unsafe food containing such a substance;
 only when the amount of that substance exceeds the level fixed by a
tolerance is the food deemed to be adulterated.

   The first sentence of Section 406, then, does not directly address
the circumstance in which a substance is required or unavoidable and a
tolerance has not been established.  However, the second sentence of
Section 406 offers guidance as to how the statute operates in that
situation.  It provides that while a tolerance is in effect, a food
containing an added poisonous or deleterious substance that is
required in food production or is unavoidable is not deemed to be
adulterated under Section 402(a)(1).  The clear implication of this
sentence is that Section 402(a)(1) does apply if no tolerance is in
effect.  In other words, the existence of a tolerance operates to
exempt tainted food from the general adulteration standard found in
Section 402(a)(1);  in the absence of a tolerance, food is still
subject to that section, under which a food is adulterated if it
contains an added poisonous or deleterious substance "which may render
(the food) injurious to health." The court of appeals therefore
misread Section 406 by construing it to require the FDA to set
tolerances for required or unavoidable added poisonous or deleterious
substances in order to exempt food containing such substances from the
automatic adulteration provisions of Sections 406 and 402(a)(2)(A).

   Any other conclusion would be inconsistent with this Court's
description of the statutory scheme in Flemming v. Florida Citrus
Exchange, supra.  There, the Court construed Section 406 to carve out
specific exemptions from the adulteration provisions in Section
402(a)(1).  As the Court explained, "(t)he existence of a tolerance is
specifically stated in Section 406(a) (currently 406) only to give
sanction to what would otherwise amount to adulteration within the
terms of Section 402(a)(1)" (358 U.S. at 166 (emphasis added)).  As
this Court recognized, when no tolerance is in effect, Section 406
does not apply to added poisonous or deleterious substances that can
be the subject of a tolerance;  Section 402(a)(1) governs instead.

   The court of appeals in essence read Section 406 as if it provides
that food containing a required or unavoidable added contaminant is
adulterated "unless" a tolerance is in effect.  However, Section 406
does not contain that term, even though Congress knows how to draft a
statute in that manner.  Sections 408(a), 409(a), and 706(a) of the
FDCA provide that pesticides, color additives, and food additives are
deemed to be unsafe for purposes of Section 402(a)(1) "unless" there
is a tolerance or exemption already in effect.  See 21 U.S.C. 346(a)
(pesticides);  348(a) (food additives);  376(a) (color additives).
That difference cannot be attributed to mere legislative oversight;
on the contrary, where "'Congress includes particular language in one
section of a statute but omits it in another section of the same Act,
it is generally presumed that Congress acts intentionally and
purposely in the disparate inclusion or exclusion'" (Russello v.
United States, 464 U.S. 16, 23 (1983) (citation omitted)).  The court
of appeals thus erred by failing to recognize that, in the absence of
a tolerance, Section 406 does not render adulterated food containing
required or unavoidable added contaminants.

   b. The FDA's Interpretation of Section 406 Gives Effect To The Role
Played By Section 402(a)(1) In The Overall Regulatory Scheme.  It is a
cardinal rule of statutory interpretation that a statute should be
construed so as to give effect to all of its provisions.  See, e.g.,
Dickerson v. New Banner Institute, Inc., 460 U.S. 103, 118 (1983);
American Textile Manufacturers Institute, Inc. v. Donovan, 452 U.S.
490, 513 (1981).  Here, the FDA's construction satisfies this precept,
while the court of appeals' interpretation makes Section 402(a)(1)
superfluous for "added" substances like aflatoxin, even though Section
402(a)(1) was expressly designed to play a role in their regulation.
/18/

   Under Section 406, the addition of a poisonous or deleterious
substance automatically renders a food "unsafe" (and thus
"adulterated" under Section 402(a)(2)(A)) if the added substance is
not required in the production of food or can practicably be avoided.
Therefore, it is undisputed that Section 402(a)(1) is not needed to
regulate those substances.  This obviously leaves only added
substances that are required or unavoidable.  As previously noted, the
FDA's view is that it may regulate such added substances either by
issuing action levels and bringing suit in appropriate cases under
Section 402(a)(1) (in which case the FDA must prove in court that the
added substance may render the food "injurious to health") or by
promulgating regulations establishing tolerances under Section 406 (in
which case any food exceeding those tolerances is automatically deemed
to be unsafe and adulterated under Section 402(a)(2)(A)).  See Ciba
Corp. v. Weinberger, 412 U.S. 640, 643-644 (1973) (agencies may
regulate by formal rulemaking or case-by-case adjudication);  NLRB v.
Bell Aerospace Co., 416 U.S. 267, 294 (1974) (same);  SEC v. Chenery
Corp., 332 U.S. 194, 201-203 (1947) (same).  The agency's
interpretation assigns an important role to both Section 402(a)(1) and
Section 402(a)(2)(A).

   Under the court of appeals' construction, however, the FDA must
issue regulations establishing formal tolerances for all required or
unavoidable added contaminants.  Once these tolerances are in effect,
Section 402(a)(1) has no role to play:  If a food is "unsafe" under
Section 402(a)(2)(A) by virtue of a formal tolerance issued under
Section 406, the FDA would have no need to proceed under Section
402(a)(1), which requires proof in court of a reasonable possibility
of injury to health;  on the other hand, if a food is deemed to be
"safe" under such a tolerance, Section 406 expressly provides that the
food "shall not, by reason of bearing or containing any added amount
of such substance, be considered to be adulterated" under Section
402(a)(1).  Furthermore, under the court of appeals' interpretation,
if a tolerance is not in effect, a food is "unsafe" under Section 406
and thus adulterated under Section 402(a)(2)(A), once again leaving
Section 402(a)(1) with no role to play.  The court's construction of
Section 406 -- rendering adulterated all food containing any required
of unavoidable added contaminant, in the absence of a tolerance --
thus would effectively eliminate from the FDCA the basic safety
standard established by Section 402(a)(1) for all added substances.

   Nor can the decision below be defended, as respondents suggest (Br.
in Opp. 10), on the ground that Section 402(a)(1) will govern added
substances whenever a new added contaminant is discovered until a
tolerance is adopted.  When Section 406 was enacted in 1938, the FDCA
did not provide that Section 402(a)(1) would serve a transitional role
until tolerances could be promulgated, although Congress has enacted
other interim measures to serve that purpose.  See, e.g., the Color
Additive Amendments of 1960, Pub. L. No. 86-618, Section 203, 74 Stat.
404-407 (authorizing provisional listing of color additives).
Moreover, respondents have identified nothing in the statute that
would allow enforcement of the Act on a case-by-case basis, using
action levels for newly discovered contaminants but not for
long-recognized contaminants.  And because Section 402(a)(1) does not
set any transitional period, courts would be forced to engage in a
standardless line-drawing exercise in order to determine when Section
402(a)(1) suddenly became ineffective and Section 402(a)(2)(A) came
into play.  There is no evidence indicating that Congress intended the
FDCA to operate in this peculiar way.  If the practical necessities of
protecting the public health are an important consideration in the
construction of the FDCA, as respondents appear to concede (Br. in
Opp. 10), these matters are best left to the expert agency that
Congress has entrusted with this responsibility.

 2. The FDA's Construction Of Section 406 Is Consistent With The Role
That Provision Plays In The Enforcement Process

   As we have shown, the structure of 21 U.S.C. 342(a)(1) and 346
supports the agency's construction of the statute.  Beyond that, the
legislative background to the FDCA confirms that the agency's position
is fully consistent with the role that Section 406 was meant to play
in the enforcement process.  Two laws are significant here:  the
Federal Food and Drugs Act of 1906, ch. 3915, 34 Stat. 768 et seq.,
the first comprehensive federal food safety legislation, and the
Federal Food, Drug, and Cosmetic Act of 1938, ch. 675, 52 Stat. 1040,
21 U.S.C. 301 et seq., which was the product of several years of
intensive legislative study as both Congress and the FDA considered
several different proposals to amend the 1906 Act.  See generally C.
Dunn, Federal Food, Drug, and Cosmetic Act (1938);  Cavers, The Food,
Drug, and Cosmetic Act of 1938:  Its Legislative History and Its
Substantive Provisions, 6 Law & Contemp. Probs. 2 (1939).  /19/ The
background to Section 406, as reflected in these two statutes, reveals
that the court of appeals misconstrued the purpose and effect of this
section.

   a. The Federal Food and Drugs Act of 1906.  Section 7 of the 1906
Act stated that a food was adulterated if it contained "any added
poisonous or other added deleterious ingredient which may render such
article injurious to health." Section 7 Paragraph Fifth, 34 Stat. 770
(codified at 21 U.S.C. (1928 ed.) 8 Paragraph "Food").  Within a
decade of its enactment, this Court construed Section 7 to reach foods
containing such an added substance if the food, "by any possibility,"
may injure the health of any consumer, "the strong and the weak, the
old and the young, the well and the sick." United States v. Lexington
Mill & Elevator Co., 232 U.S. 399, 411 (1914).

   So construed, the 1906 Act provided a valuable instrument for
protecting the public health.  Nonetheless, the FDA concluded that
additional enforcement powers would strengthen its hand in two ways.
First, in an enforcement proceeding under the 1906 Act each food had
to be considered by itself, and exposure to small amounts of the same
poisonous or deleterious substance found in a variety of common foods
in the diet could not be taken into account in a single proceeding.
/20/ In addition, unlike today, when federal agencies are often
empowered to adopt regulations having the force and effect of law (see
Chrysler Corp. v. Brown, 441 U.S. 281, 295-298 (1979)), the Federal
Food and Drugs Act of 1906 did not authorize the Department of
Agriculture, the agency then responsible for enforcing that Act, to
issue legislative rules defining categories of forbidden substances.
The FDA had adopted informal standards for a number of added
substances, such as pesticides.  /21/ But the FDA was required to
prove in court on a case-by-case basis that a particular food was
adulterated (see United States v. Washington Dehydrated Food Co., 89
F.2d 606 (8th Cir. 1937)), a process that the agency had to repeat for
each new substance and party.  Accordingly, when Congress began its
consideration of a successor to the 1906 Act, the FDA sought to add to
its enforcement power by persuading Congress to grant the agency the
discretionary authority to adopt legislative rules applicable to broad
classes of contaminants.  /22/

   b. The Federal Food, Drug, and Cosmetic Act of 1938.  The FDCA
originated in the 73d Congress when the FDA, which drafted the
original version of the Act, /23/ submitted a bill (S. 1944, 73d
Cong., 1st Sess. (1933)) to replace the 1906 Act.  Section 10(a) of
that proposal, according to Walter Campbell, Chief of the FDA, granted
the agency quasi-legislative authority to establish tolerances setting
precise levels of forbidden contamination.  /24/ This section -- which
FDA Chief Campbell called "an extremely important, in fact, one of the
most important provisions of this bill" (1933 S. 1944 Hearings 18) --
was intended to augment the agency's authority under the existing Act
and Lexington Mill by empowering the FDA to make factual findings that
took into account the range of poisons found in the diet and by
allowing the agency to obviate the case-by-case adjudication then
required to prove adulteration.  /25/ The bill submitted by the agency
thus clearly provided an additional enforcement tool, not a substitute
for its existing authority.

   Although the court of appeals found that the verb "shall" in the
current version of Section 406 of the FDCA was "critical" to a
"common-sense" understanding of the meaning of this provision (Pet.
App. 6a), neither the FDA nor Congress attributed any significance to
this term;  in fact, both the FDA and Congress used the verbs "shall"
and "is authorized to" interchangeably.  The bill drafted by the FDA
used the verb "shall," yet the agency interpreted that bill as
authorizing, not requiring, the agency to promulgate tolerances.  /26/
Senator Copeland, the sponsor of the bill drafted by the agency,
stated that the proposal authorized the FDA to adopt tolerances.  /27/
The FDA consistently took the position during the congressional
hearings on the various bills that the agency should be authorized,
not required, to issue tolerances.  /28/ Some of the bills that
Congress considered, such as the version drafted by the FDA, used the
verb "shall" in connection with the provision that was ultimately to
become Section 406 of the FDCA;  /29/ other bills used the term "is
authorized to".  /30/ Nonetheless, each of the committee reports
explaining these antecedents to Section 406, including the bill
eventually enacted as that law, stated that it authorized the FDA to
promulgate tolerances.  /31/

   Throughout the lengthy hearings on the Act, no one proposed that
the term "shall" should be inserted into the Act to require the FDA to
promulgate tolerances, no one argued that the case-by-case method of
proving adulteration under Lexington Mill should be jettisoned in
favor of exclusive reliance upon tolerances, and no one criticized the
FDA for jeopardizing the public health by refusing to initiate
enforcement proceedings.  Rather, the controversy generated by the
tolerance-setting features in these legislative proposals stemmed from
the procedures by which the FDA would set tolerances, as well as the
limited scope of judicial review available to a party seeking to have
a tolerance set aside.

   The apple industry, which used pesticides to control insect
infestation, opposed the FDA's proposal to adopt tolerances for
foodstuffs largely on procedural grounds.  It complained that a
tolerance could be set without the adversarial hearings required by
the 1906 Act before a food could be deemed adulterated, and that
judicial review was limited to the question whether a tolerance was
arbitrary and supported by substantial evidence.  Given the
abbreviated administrative procedures necessary to set a tolerance,
/32/ the fact that a tolerance only required the government to prove
that a specific level of contamination had been exceeded, and the
narrow scope of judicial review, the apple industry claimed that the
proposed tolerance provisions would radically alter the nature of
criminal prosecutions for adulteration.  /33/ The industry's fear was
that the substantive tolerance-setting provisions would shift to the
defendant the burden of proof on the issue whether a food was
adulterated, while the procedural aspects of these provisions (i.e.,
dealing with the administrative issuance of a tolerance and subsequent
judicial review) would emasculate the defendant's ability to prove
that the agency's judgment was wrong.  Authorizing the FDA to set
tolerances vested undue power in its hands, the industry argued, which
could be exercised in an arbitrary manner.

   In response, the House of Representatives amended the Senate bill
(S. 5, 75th Cong., 3d Sess. (1938)) to accommodate the concerns of the
apple industry while still strengthening the FDA's hand.  The House
imposed elaborate administrative requirements before a tolerance could
be issued and rewrote the judicial review features of the bill,
Sections 701-703, in order to subject a tolerance to exacting
administrative and judicial scrutiny before it could become effective.
 /34/ However, the House bill still empowered the FDA to issue
tolerances.  Although the House substituted the verb "shall" for the
term "is authorized to" in Section 406(a) of the Senate bill, which
granted the FDA the authority to set tolerances, the House did not
modify the substance of that section.  The House Report described
Section 406(a) as authorizing, not requiring, the agency to issue
tolerances.  See H.R. Rep. 2139, supra, at 6 (emphasis added):  "This
subsection first prohibits the unnecessary addition of poisons.  Where
such additions are necessary, the establishment of tolerances is
authorized, based upon the practical necessities for the use of
poisonous substances." Moreover, both supporters and opponents of the
elaborate administrative and judicial procedures in Sections 701-703
of S. 5, supra, agreed that, in regard to Section 406(a), "(t)his bill
provides that the Secretary of Agriculture shall have the authority
after proper hearing to prescribe the extent of spray residue that
shall be permissible" (83 Cong. Rec. 7774 (1938) (Rep. Lea) (emphasis
added)), and that, "(i)f enacted, this bill would give (the FDA) the
right after proper hearings to adopt regulations prescribing limits
(on pesticide residues)" (ibid. (emphasis added)).  /35/

   In sum, as one contemporary observer noted, "(t)he section defining
the Secretary's powers (under Section 406(a)) was constantly revised
during the evolution of the measure, but in the end did not greatly
differ from that in S. 1944 (the original bill drafted by the FDA).
The major battle arising from this provision was fought on the issue
of judicial review * * *." Cavers, supra, 6 Law & Contemp. Probs. at
27.

   c. The Effect Of Section 406.  The foregoing discussion
demonstrates that the court of appeals misapprehended the import of
Sections 402(a)(1) and 406 of the FDCA.  As noted, the court of
appeals' decision is bottomed in part on its belief that, in the
absence of a tolerance, the presence in food of any amount of a
required or an unavoidable added poisonous or deleterious substance
violates the law, even if the level of that substance in food cannot
pose any danger to human health.  However, the FDCA has never
incorporated that concept of adulteration.  This Court squarely
rejected that proposition in Lexington Mill in construing the
predecessor 1906 Act, ruling that an added poisonous or deleterious
substance must present a reasonable possibility of injury to the
public health before the Act comes into play.  See 232 U.S. at
410-411;  page 26, supra.  In the FDCA, Congress retained the
prohibition in Section 7 of the 1906 Act, interpreted in Lexington
Mill, forbidding any "added substance" in food that is poisonous or
deleterious and that "may render it injurious to health" (Section
402(a)(1), 21 U.S.C. 342(a)(1)), thereby making clear that it intended
to retain the substance of the 1906 Act as that law had been construed
by this Court.  S. Rep. 493, 73d Cong., 2d Sess. 3 (1934);  S. Rep.
361, 74th Cong., 1st Sess. 6 (1935);  cf. Lorillard v. Pons, 434 U.S.
575, 580-581 (1978).  /36/ The Court recognized in Flemming v. Florida
Citrus Exchange, supra, that the interpretation of "adulteration"
adopted in Lexington Mill was carried forward into the current version
of the FDCA, stating that "(t)he language involved in Lexington Mill
survived generally in the Act's broadest and most general test of food
adulteration, Section 402(a)(1)." 358 U.S. at 161.

   The court of appeals also erred by construing Section 406 as
imposing a mandatory duty on the FDA to promulgate tolerances.  The
legislative history of Section 406 shows that it was designed to arm
the FDA with the power to establish tolerances for the variety of
foods in which a common poison was required or unavoidable so that the
agency could employ an additional enforcement weapon against the
interstate shipment of adulterated food.  The FDA drafted the original
version of this section to obtain discretionary authority to
promulgate tolerances;  Congress used the terms "shall" and "is
authorized to" interchangeably when considering the FDCA;  and no one
challenged that interpretation of these bills.  The sole opposition to
the tolerance-setting provisions centered on the concern that the FDA
would adopt tolerances too readily, not that the agency would fail to
issue such regulations.  In sum, by reading Section 406 as requiring
the FDA to promulgate tolerances in order to exempt a food containing
a required or unavoidable added contaminant from being adulterated,
the court of appeals stood Section 406 on its head.  /37/

   It is, in addition, extremely significant that the FDA did not
contemporaneously interpret the bill adopted by the House as requiring
the agency to set tolerances.  The agency did not object to the House
amendment to S. 5 on that ground (see H.R. Rep. 2139, supra, Pt. 2, at
3-4 (Minority Report) (reprinting letter from Secretary of Agriculture
Wallace to Rep. Mapes criticizing the amendments made by the House
Committee));  nor did the FDA immediately promulgate tolerances to
exempt contaminated food from the scope of the newly-enacted Section
406, which would have been the obvious and necessary response to
Congress's imposition on the FDA of the duty to do so.  Moreover, if
the court of appeals' construction of Section 406 were correct, then
the members of the apple industry, who had opposed the grant of an
unreviewable tolerance-setting authority to the FDA, would have become
outlaws on the day the FDCA went into effect, since no tolerances had
yet been promulgated permitting them to use pesticides.  Finally, to
our knowledge, no member of Congress ever criticized the FDA for
failing to undertake the duty that the court of appeals found sprang
into being once the FDCA became effective.  That is powerful evidence
that Congress never imposed any such duty in the first place.

 B. The FDA's Longstanding Construction Of The FDCA Is Entitled To
Substantial Deference

   The structure, purpose, and legislative background of the FDCA thus
provide substantial support for the agency's construction of Section
406.  Beyond that, a variety of factors at work here present a
powerful case for deference to the FDA.  The FDA played an important
role in drafting the statute (see Miller v. Youakim, 440 U.S. 125, 144
(1979));  the interpretation at issue involved a contemporaneous
construction of the statutory language (see Udall v. Tallman, 380 U.S.
1, 16 (1965));  the FDA has consistently adhered to that construction
for nearly 50 years (see Zenith Radio Corp. v. United States, 437 U.S.
443, 450 (1978));  Congress has never expressed its dissatisfaction
with the FDA's regulatory approach despite making revisions to related
provisions of the FDCA (see United States v. Rutherford, 442 U.S. 544,
554 n.10 (1979));  in fact, Congress expressly noted and relied upon
the agency's views when enacting those modifications (see Riverside
Bayview Homes, Inc., slip op. 13-15);  and, of course, Sections 402
and 406 are central portions of a complex regulatory scheme that the
FDA is charged with administering (see Central Lincoln, slip op. 8).

 1. The FDA Hbas Followed An Unwavering Construction Of 21 U.S.C. 342
And 346 Since The Inception Of The FDCA Nearly A Half-Century Ago

   For almost 50 years, the Secretary has consistently and publicly
interpreted the FDCA as providing the FDA with the discretion to
select between informally adopted action levels or formal tolerances
to prevent the distribution of adulterated foods in interstate
commerce.  The FDA took this position from the outset, stating that
Section 406 "authorized" the agency to promulgate tolerances.  See
Trade Correspondence 136 (Mar. 7, 1940), reprinted in 1 V. Kleinfield,
C. Dunn, & A. Kaplan, supra, at 622 (page 17 note 14, supra).  /38/
The agency has also ahered to this position to the present.  In 1974,
for instance, in proposing regulations to govern the decision when
formal tolerances should be promulgated, the agency stated explicitly
that, under the Act, "(t)he Commissioner is not required to establish
a tolerance for every added poisonous or deleterious substance * * *."
39 Fed. Reg. 42745.  Three years later, the FDA issued regulations
setting forth guidance as to when the FDA would proceed by formal
tolerances rather than by action levels.  See 21 C.F.R. 109.6(b) and
(c).  These regulations are necessarily premised on and manifest the
agency's belief that it had not been precluded by Congress from
selecting between these alternatives.  And the decided cases
acknowledge that the FDA has relied on action levels in enforcing the
food adulteration provisions of the FDCA.  See, e.g., United States v.
Boston Farm Center, Inc., supra;  United States v. Goodman, supra;
pages 18-19, supra.  The agency's historic and unwavering
interpretation of Section 406 is therefore entitled to substantial
deference.  See Chevron, slip op. 5-7;  Rutherford, 442 U.S. at
553-554.

   To be sure, the court of appeals' literal reading of the statute is
not irrational.  The word "shall," Justice Cardozo once wrote for the
Court, "is the language of (a) command" (Escoe v. Zerbst, 295 U.S.
490, 493 (1935)).  But he also made clear that the plain meaning of
this term was "not controlling", because the courts must consider "a
view of the ends and aims" of the legislation under consideration
(ibid.).  Here, the court of appeals did not deny that the FDA's
interpretation of the statutory language was entirely rational and
plausible.  Nor did the court find that the agency's interpretation of
the Act was forclosed by its legislative history, created internal
inconsistencies in the overall structure of the FDCA, produced
anomalous results that Congress could not have intended, or created a
regulatory loophole threatening the public health.  The dictionary
meaning of the term "shall" therefore provides no basis for overriding
the agency's historic interpretation of a statute that it has been
entrusted by Congress to administer, especially in view of the
statute's obvious complexity.  See Pattern Makers v. NLRB, No. 83-1894
(June 27, 1985), slip op. 19;  Chemical Manufacturers Ass'n v. NRDC,
No. 83-103 (Feb. 27, 1985), slip op. 8.  As the Court has remarked,
the FDCA must "be treated as a working instrument of government and
not merely as a collection of English words." United States v.
Dotterweich, 320 U.S. 277, 280 (1943).  Since the FDA's construction
of Section 406 implements the Act in this manner, the statute should
not be construed to defeat the agency's longstanding interpretation.
/39/

 2. Congress Has Endorsed The FDA's Construction Of The FDCA In
Amending The Act

   Longevity is not the sole factor militating in favor of the FDA's
construction of the FDCA.  The FDA's interpretation is entitled to
enhanced deference because Congress specifically noted the agency's
position while considering revisions of the FDCA and did nothing to
alter that administrative practice.  See, e.g., Haig v. Agee, 453 U.S.
280, 297-298 (1981);  Chemehuevi Tribe of Indians v. FPC, 420 U.S.
395, 410 (1975);  NLRB v. Gullett Gin Co., 340 U.S. 361, 366 (1951).
Indeed, the legislative history of 21 U.S.C. 346a, which was adopted
to modify Sections 402(a)(1) and 406, shows that Congress approved and
relied upon the agency's position.

   Under the FDCA, pesticides in food were originally governed by
Section 406, 21 U.S.C. 346.  However, in 1954 Congress enacted a new
statute, 21 U.S.C. 346a, to regulate the presence of pesticide
residues in raw agricultural commodities.  /40/ During the
congressional hearings on this legislation, both the Commissioner of
Food and Drugs and industry representatives expressly called to
Congress's attention the FDA's position on the meaning of Section 406.
 /41/ Thereafter, the agency's construction not only was expressly
noted without objection by both the House and Senate committees, but
also appears to have played an important part in their thinking.  See
H.R. Rep. 1385, 83d Cong., 2d Sess. 2, 3, 6-7 (1954);  S. Rep. 1635,
83d Cong., 2d Sess. 2, 3, 6-7 (1954).

   For instance, the House Report, in describing the existing law,
noted that when an added poisonous or deleterious substance is
required in food production or practically unavoidable, "a tolerance
may be established by the Secretary" (H.R. Rep. 1385, supra, at 2
(emphasis added)).  The House Report also recognized that the FDA from
the outset had adhered to and implemented its position that Section
406 was discretionary, observing that, while the law "authorizing" the
issuance of formal tolerances had been in effect for more than 15
years, "(d)uring all that time control has been exercised through
unofficial and informal tolerances" (ibid.).  The House Report
continued (id. at 2-3) that in 1950 "lengthy public hearings," costing
nearly $500,000, had been held for the purpose of establishing
official tolerances for pesticide residues in fresh fruits and
vegetables but that official tolerances still had not been promulgated
due to "the cumbersome, time-consuming, and impracticable procedure
prescribed by existing law." To overcome these difficulties, the House
committee recommended "an improved procedure for establishment of
tolerances for pesticide chemicals remaining in or on raw agricultural
commodities" (id. at 2).  And to implement this goal, Section 3 of the
Act ultimately adopted (Act of July 22, 1954, ch. 559, 68 Stat. 511 et
seq.), according to the House Report, "gives to the Secretary * * *
the authority to establish tolerances" (H.R. Rep. 1385, supra, at 8).
The Senate Report made the identical points.  See S. Rep. 1635, supra,
at 2, 3, 6, 8.

   Thus, the congressional committees expressly observed that the FDA
was relying chiefly on informal rather than formal tolerances, yet
they didnot suggest that this practice was unlawful or undesirable,
and they did nothing to require its abandonment in favor of exclusive
reliance on formal rulemaking.  On the contrary, both committees
sharply criticized the formal statutory procedure set out in the FDCA
and crafted a new, simpler, and speedier method for rectifying the
problem caused by the breakdown of the formal procedure in the field
of pesticide residues on raw agricultural commodities.  Beyond that,
although the statute Congress adopted provides that "(t)he
Administrator shall promulgate regulations establishing tolerances * *
* to the extent necessary to protect the public health" (21 U.S.C.
346a(b);  see pages 39-40 note 40, supra), both the House and Senate
Reports expressly described this provision as authorizing, not
mandating, the adoption of formal tolerances, much as Congress had
done when it adopted Section 406 of the FDCA.  See H.R. Rep. 1385,
supra, at 8;  S. Rep. 1635, supra, at 2, 3, 6, 8.  /42/

   The history of these amendments to the FDCA shows beyond question
that Congress endorsed the FDA's interpretation of the statutory
provisions at issue.  As the Court has made clear, "once an agency's
statutory construction has been 'fully brought to the attention of the
public and the Congress,' and the latter has not sought to alter that
interpretation although it has amended the statute in other respects,
then presumably the legislative intent has been correctly discerned."
Rutherford, 442 U.S. at 554 n.10.  Indeed, here, Congress did more
than decline to disturb the FDA's views;  it actually incorporated
those views into the new statute.  Cf. Riverside Bayview Homes, slip
op. 15;  Bob Jones University, 461 U.S. at 601-602.

 3. The Court Of Appeals' Ruling Hampers The Effective Enforcement Of
The FDCA

   Respondents have not suggested, and the courts below did not find,
that the 20 ppb action level set by the FDA for aflatoxin does not
adequately protect the public health, that formal tolerances are
essential to prevent the interstate shipment of adulterated food, or
that the FDA is not satisfactorily enforcing the FDCA.  Nor did
respondents offer any evidence to support such a claim.  In fact, the
historical record reveals that the FDA has vigorously enforced Section
402(a)(1) against added contaminants in food.  /43/

   The court of appeals no doubt assumed that its construction of the
FDCA would contribute to the effective enforcement of the Act.  Cf.
United States v. An Article of Drug * * * Bacto-Unidisk, 394 U.S. 784,
798 (1969) (noting that the FDCA should be liberally construed in
order to protect the public health);  Dotterweich, 320 U.S. at 284
(same).  /44/ Quite the contrary is true, however.  Unless reversed,
the court of appeals' decision will have a significant adverse impact
on the administration of the Act.

   First, and most important, formal tolerances, once set, may retard
the FDA's ability to respond quickly to new scientific findings or
improvements in manufacturing processes that make it practicable to
reduce the level of adulterants.  See 21 C.F.R. 509.6(b)(3).  Unlike
other statutory provisions authorizing the emergency ban of pesticides
(see 7 U.S.C. 136d(c)(3)) or drugs (see 21 U.S.C. 355(e)) found to
pose an imminent hazard to the public health, the FDCA makes no
provision for either the emergency revocation of a tolerance or the
emergency condemnation of food meeting a tolerance.  Once a formal
tolerance is in effect, a food that does not exceed that tolerance is
automatically deemed to be safe and unadulterated under Sections
402(a)(2)(A) and 406, 21 U.S.C. 342(a)(2)(A) and 346.  Moreover,
Section 406 provides that the food may not then be considered to be
adulterated within the meaning of Section 402(a)(1) -- even if the
government could prove in court that the food may be "injurious to
health." Thus, if a formal tolerance is issued and it is later
discovered that the limit is too high, foods that satisfy the formal
tolerance but that may in fact be unsafe according to the latest
scientific studies will still be considered safe and unadulterated
under the FDCA until the lengthy process of issuing a new, lower
tolerance can be completed.  /45/

   Second, the court of appeals' reading of the statute would impose a
severe administrative burden on the FDA and require the reallocation
of scarce resources from activities of far greater utility in
protecting the public health.  Although the FDA originally expected
that the authority to adopt tolerances would prove to be a valuable
addition to the agency's enforcement arsenal, the exacting
administrative and judicial review process imposed by Congress in
Section 701, 21 U.S.C. 371 largely defeated the agency's hopes.
Despite showing some initial promise, /46/ the tolerance-setting
procedures, the FDA has learned, are often protracted and can
seriously hamper the agency's ability to respond quickly to new
developments.  /47/ Congress, too, has found that the formal
rulemaking procedures set forth in Section 701(e) are "cumbersome,
time-consuming, and impracticable." S. Rep. 1635, supra, at 2;  H.R.
Rep. 1385, supra, at 3.

   Nonetheless, court of appeals' decision would mandate such
proceedings for numerous substances.  The FDA currently has 21 action
levels for eight added substances that could be regarded as within the
scope of Section 406.  /48/ These substances can contaminate foods
such as red meat, fish, milk and dairy products, eggs, corn, and
wheat.  See J.A. 150, 156, 165, 166, 167.  Since a different action
level may be necessary for each of several human foods and animal
feeds, a given substance can require several action levels.
Therefore, a tolerance-setting proceeding under Section 701(e) might
likewise include a number of tolerances for each substance, depending
on the food or feed involved.  The greater the number of foods or
feeds considered, the more complicated and time consuming the
proceeding would be.  The decision below, at the least, would seem to
require that each of the FDA's current action levels be replaced by a
formal tolerance.  /49/

   Of course, the burden of establishing tolerances through the formal
rulemaking process is not a sufficient reason for failing to do so if
Congress required the FDA to regulate in this manner.  But the FDA has
found that the establishment of formal tolerances does not protect the
public health to any significant degree beyond that afforded by its
reliance on informal action levels.  The FDA has long viewed the
decision whether to establish formal tolerances as largely a question
whether doing so will enhance its ability to enforce the food
adulteration provisions of the FDCA by obviating the need to prove in
court on a case-by-case basis that a certain food may present a danger
to the public health by virtue of the particular level of a specific
contaminant that it contains.  Given the negligible addition to its
enforcement power resulting from the establishment of tolerances, and
the risk that their adoption might reduce (or, in some cases,
eliminate) the flexibility necessary to respond to changed
circumstances, the FDA has found that formal tolerances are not
currently essential to its regulatory mission.  There is no evidence
that Congress disagrees with FDA's considered view, which represents
precisely the type of scientific and policy judgment that Congress
commonly entrusts to the administrative agency responsible for
enforcing a complex regulatory scheme.  See Heckler v. Chaney, No.
83-1878 (Mar. 20, 1985), slip op. 10;  Chevron, slip op. 5-7.
Construing the FDCA to require the FDA to adopt formal tolerances in
these circumstances would hinder rather than promote the Act's purpose
of protecting the public health by needlessly diverting the agency's
limited resources from matters of more urgent public concern.

   Finally, the reasoning of the court of appeals casts a cloud over
the legality of large portions of the nation's food supply.  As noted
above, the court of appeals was under the mistaken belief that unless
a formal tolerance has been issued any food containing an added,
unavoidable poisonous or deleterious substance must be considered to
be adulterated.  Pet. App. 15a.  Because many segments of the food
supply now contain such substances (albeit in safe amounts), the
necessary implication of the court's reasoning is that this food is
"adulterated" within the meaning of 21 U.S.C. 342(a)(2)(A) and that
persons responsible for growing, processing, or distributing it in
interstate commerce are in violation of 21 U.S.C. 331 and are subject
to an injunction (see 21 U.S.C. 332), seizure of the food (see 21
U.S.C. 334), or even criminal penalties (see 21 U.S.C. 333).  For
those potentially affected, it is cold comfort that the government
would exercise its enforcement discretion in a fair and reasonable
manner.  See 21 U.S.C. 336;  Heckler v. Chaney, supra.  The affected
parties ought not to be subjected to that risk in the absence of far
clearer evidence than the court of appeals was able to muster that
Congress intended the regulatory process to be structured in an
entirely different fashion.

                              CONCLUSION

   The judgment of the court of appeals should be reversed.

   Respectfully submitted.

   CHARLES FRIED

      Solicitor General

   RICHARD K. WILLARD

      Assistant Attorney General

   KENNETH S. GELLER

      Deputy Solicitor General

   PAUL J. LARKIN, JR.

      Assistant to the Solicitor General

   LEONARD SCHAITMAN

   MARLEIGH D. DOVER

      Attorneys

   THOMAS SCARLETT

      Chief Counsel

   MICHAEL M. LANDA

      Associate Chief Counsel for Enforcement Food and Drug
      Administration

   FEBRUARY 1986

   /1/ Pursuant to Section 701(a) of the FDCA, 21 U.S.C. 371(a), and
under the authority delegated to him by the Secretary (21 C.F.R.
5.10), the Commissioner of Food and Drugs is authorized to enforce the
FDCA.

   /2/ The FDA's action levels have been publicly available since
1972.  Prior to that time, the agency's action levels were generally
treated as confidential internal policy matters.  See 37 Fed. Reg.
6497 (1972).  Current action levels are reprinted at J.A. 148-168.

   /3/ The term "added" is not defined in the FDCA.  The FDA's
regulations define an "added" poisonous or deleterious substance as
one that "is not a naturally occurring * * * substance" (21 C.F.R.
109.3(d), 509.3(d)), and, in turn, define a "naturally occurring
poisonous or deleterious substance" as "a poisonous or deleterious
substance that is an inherent natural constituent of a food and is not
the result of environmental, agricultural, industrial, or other
contamination" (21 C.F.R. 109.3(c), 509.3(c)).  See also 42 Fed. Reg.
52814-52816 (1977);  39 Fed. Reg. 42743-42744 (1974);  J.A. 13-15,
55-56, 56-57, 61-63.

   /4/ The general adulteration standard set forth in Section
402(a)(1) is supplemented by other provisions containing more specific
safety standards for pesticides (see 21 U.S.C. 346a), food additives
(see 21 U.S.C. 348), color additives (see 21 U.S.C. 376), and new
animal drugs (see 21 U.S.C. 360b).

   /5/ See Flemming v. Florida Citrus Exchange, 358 U.S. 153, 161
(1958);  United States v. Coca Cola Co., 241 U.S. 265, 277, 283
(1916);  United States v. Lexington Mill & Elevator Co., 232 U.S. 399
(1914).

   /6/ See Continental Seafoods, Inc. v. Schweiker, 674 F.2d 38, 41
(D.C. Cir. 1982);  United States v. Anderson Seafoods, Inc., 622 F.2d
157, 159 (5th Cir. 1980).

   /7/ These factors include (1) the level necessary to protect the
public health, (2) the extent to which the substance is unavoidable,
(3) the effect of other poisonous or deleterious substances on the
public health, and (4) the ability of analytical methods to detect and
quantify the substance when it is discovered in food.  21 C.F.R.
109.6, 509.6;  J.A. 21-22.  The FDA considers the overall economic
impact of the permitted level in connection with the second factor.
See 42 Fed. Reg. 52816 (1977).

   /8/ Respondents challenged this practice below, but the court of
appeals did not address the point (Pet. App. 2a).

   /9/ See also United States v. Boston Farm Center, Inc., 590 F.2d
149, 153 (5th Cir. 1979) ("(t)he statute does not demand rigid and
permanent fixity in the numbers game, mainly because our social
policies and scientific knowledge about dangerous food are not
themselves steady and static");  United States v. Goodman, 486 F.2d
847, 854 (7th Cir. 1973) (finding that an in-depth consideration of
tolerances for DDT when DDT levels in the environment were in a state
of flux would be "virtually meaningless").

   /10/ An FDA study, "Aflatoxin-Contaminated Corn, Limited Exemptions
from Prohibition of Interstate Shipment and Blending, Assessment of
Safety and Impact on the National Food Supply" (Dec. 1980) (J.A.
202-211), concluded that the largest portion of corn containing
aflatoxin that was ingested by food-producing animals is eliminated in
excreta.  Id. at 203.  Although residues of aflatoxin may be found in
the edible tissues of those animals under certain circumstances, so
long as the level of aflatoxin in corn fed to the animals identified
in the text did not exceed 100 ppb, the level of aflatoxin in their
edible tissues would not exceed 0.1 ppb, the lowest level that can
consistently be identified and measured in tissues by available
analytical methods.  Id. at 203-206.  The FDA thus concluded that the
meat and eggs from animals eating corn containing 20-100 ppb aflatoxin
were "safe" for consumption within the meaning of 21 C.F.R. 509.8,
i.e., that "all available toxicological data indicate that no
significant health hazard is involved." 39 Fed. Reg. 42746 (1974).

   In 1978, responding to a similar situation, the FDA temporarily
authorized the blending of corn containing more than 20 ppb aflatoxin
with untainted corn to achieve a level of up to 20 ppb aflatoxin and
the subsequent interstate shipment of the blended corn.  See 43 Fed.
Reg. 14122 (1978).  In 1983, the FDA allowed corn containing alfatoxin
not exceeding 100 ppb to be shipped in interstate commerce for use as
feed for certain animals, on the ground that the corn was not
adulterated within the meaning of 21 U.S.C. 342(a)(1) for its intended
use.  See 48 Fed. Reg. 53175 (1983);  cf. J.A. 193, 194, 225.

   /11/ In September 1980, respondent Community Nutrition Institute
(CNI) learned that North Carolina and South Carolina had sought
exemptions, and the following month CNI urged the FDA to deny these
requests and any similar ones.  The FDA rejected CNI's request on
November 28, 1980, in a letter giving the reasons for the agency's
decision.  J.A. 212-216.

   /12/ Because the court of appeals reversed on this ground, it did
not consider responsdents' other claims (Pet. App. 2a).

   /13/ See, e.g., 42 Fed. Reg. 52814 (1977) ("(t)he Commissioner
advises that it is not possible to produce food or food ingredients
that are entirely free from contamination by foreign substances or
impurities.  This is not a modern phenomenon.  Wholesome foods have
inevitably been the carriers of levels of contamination beyond the
capability of contemporary processing methods to eliminate and
sometimes even detect.  At best, therefore, specifications for 'food
grade' substances can be established * * * to ensure that only minimal
levels of contaminating substances are present.");  J.A. 55.

   /14/ As the FDA there stated (emphasis added):

         The Administration, in the enforcement of old Food and Drugs
      Act, never announced formal tolerances for these substances in
      foods since no authority existed in the old law for so doing.
      The law * * * merely classified a food as adulterated if it
      contained any added deleterious ingredient which might render
      food injurious to health, leaving it a question of fact in each
      case that might arise as to whether the food was adulterated.

         We have, of course, as you know, informally announced certain
      tolerances for arsenic, fluorine and lead existing in spray
      residues on fresh fruits, these being 0.01 grain of arsenic per
      pound, 0.002 grain of fluorine per pound, and 0.025 grain of
      lead per pound.  The new Act contains practically the same
      provision as indicated above but, in addition, authorizes the
      Secretary to promulgate tolerances in the case of deleterious
      substances added to food where the addition cannot be avoided by
      good manufacturing practices or where such substance is required
      in the production of the food.

   /15/ When Flemming was decided, Section 406 of the Act consisted of
subsection (a) (which includes the current version of Section 406) as
well as subsection (b), which provided:  "(the FDA) shall promulgate
regulations providing for the listing of coal-tar colors which are
harmless and suitable for use in food and for the certification of
batches of such colors." Subsections (a) and (b) then in effect did
share the common phrase "shall promulgate regulations," but subsection
(b), unlike subsection (a), was not qualified by the phrase "to such
extent as (the FDA) finds necessary for the protection of public
health."

   /16/ Moreover, Section 306 of the FDCA, 21 U.S.C. 336, which
permits the FDA "to refrain from prosecuting minor violations," has
long been read to permit the FDA to employ action levels to implement
the adulteration provisions of the Act.  See, e.g., United States v.
Boston Farm Center, Inc., 590 F.2d at 151;  United States v. Goodman,
486 F.2d at 855;  United States v. Thriftimart, Inc., 429 F.2d 1006,
1011 (9th Cir.), cert. denied, 400 U.S. 926 (1970);  Dean Rubber
Manufacturing Co. v. United States, 356 F.2d 161, 164 (8th Cir. 1966);
 United States v. 1500 Cases More or Less, Tomato Paste, 236 F.2d 208,
211-212 (7th Cir. 1956);  United States v. 449 Cases, Containing
Tomato Paste, 212 F.2d 567, 572-573 (2d Cir. 1954);  United States v.
133 Cases of Tomato Paste, 22 F. Supp. 515, 516 (E.D. Pa. 1938).

   /17/ Section 402(a)(2)(B) involves raw agricultural commodities
containing pesticides, Section 402(a)(2)(C) involves food additives,
and Section 402(a)(2)(D) involves new animal drugs.  None of these
sections is directly relevant to this case.

   /18/ Section 402(a)(1) states, in part, that "in case the substance
is not an added substance such food shall not be considered
adulterated under this clause if the quantity of such substance in
such food does not ordinarily render it injurious to health" (emphasis
added).  This clause demonstrates that Section 402(a)(1) was meant to
govern both added and inherent substances.

   /19/ Those portions of the legislative history pertinent to
Sections 402(a)(1) and 406 are summarized in the appendix to the
amicus curiae brief of the National Food Processors Association (at
1a-5a).

   /20/ See Foods, Drugs, and Cosmetics:  Hearings on H.R. 6906 et al.
 Before a Subcomm. of the House Comm. on Interstate and Foreign
Commerce, 74th Cong., 1st Sess. 60 (1935) (Walter Campbell, Chief of
FDA) (hereinafter cited as 1935 H.R. 6906 Hearings);  Foods, Drugs,
and Cosmetics:  Hearings on S. 2800 Before the Senate Comm. on
Commerce, 73d Cong., 2d Sess. 596 (1934) (Walter Campbell)
(hereinafter cited as 1934 S. 2800 Hearings);  Foods, Drugs, and
Cosmetics;  Hearings on S. 1944 Before a Subcomm. of the Senate Comm.
on Commerce, 73d Cong., 2d Sess. 19, 24 (1933) (Walter Campbell)
(hereinafter cited as 1933 S. 1944 Hearings).

   /21/ See, e.g., 1933 S. 1944 Hearings 22, 28 (Walter Campbell);
Notice to Growers and Shippers of Fruits, Dep't of Agriculture (Apr.
2, 1933), reprinted in 1933 S. 1944 Hearings 219-220;  Notice to
Growers and Shippers of Fruits, Dep't of Agriculture (June 20, 1933),
reprinted in 1933 S. 1944 Hearings 220;  Notice to Growers and
Shippers of Fruits, Dep't of Agriculture (Dec. 11, 1933), reprinted in
1933 S. 1944 Hearings 220;  Cavers, supra, 6 Law & Contemp. Probs. at
2, 15;  Developments in the Law -- The Federal Food, Drug, and
Cosmetic Act, 67 Harv. L. Rev. 632, 642 n.73 (1954).

   /22/ 1935 H.R. 6906 Hearings 60 (Walter Campbell);  1934 S. 2800
Hearings 596 (same);  1933 S. 1944 Hearings 21, 80 (same).

   /23/ See 1934 S. 2800 Hearings 572 (Walter Campbell).

   /24/ 1933 S. 1944 Hearings 19 (Walter Campbell) ("(u)nder the terms
of this bill the Secretary will be permitted to establish
tolerances");  id. at 21 (same) ("(w)e are proposing here, in this and
other sections of the act, to have authority conferred upon
administrative officers to make certain findings of fact.  * * * If
this section of the bill were to be enacted there could be by
executive action the establishment of legal tolerances for added
deleterious ingredients");  id. at 22 (same) (noting that the public
and business is benefitted if there is "some provision * * * for an
administrative agency to be empowered on a fact finding basis to give
expression to legislative intent").

   /25/ 1933 S. 1944 Hearings 18-24, 28, 80-81 (Walter Campbell).

   /26/ See S. 1944, 73d Cong., 1st Sess. Section 10(a) (1933);  page
28 note 24, supra;  see also Annual Report of the Food and Drug
Administration (1933), reprinted at C. Dunn, supra, at 25, 28.

   /27/ See 77 Cong. Rec. 5722 (1933) (Sen. Copeland) ("Memorandum on
the Bill for Revising the Food and Drugs Act, Indicating Differences
Between Bill and Present Law");  C. Dunn, supra, at 34.

   /28/ See 1933 S. 1944 Hearings 19-21, 24, 80 (Walter Campbell);
id. at 12 (Secretary of Agriculture Wallace) ("(t)he prohibition of
added poisons in foods or the establishment of tolerances therefor is
provided for");  1934 S. 2800 Hearings 596 (Walter Campbell);  Foods,
Drugs, and Cosmetics:  Hearings on S. 5 Before a Subcomm. of the
Senate Comm. on Commerce, 74th Cong., 1st Sess. 358 (1935) (Walter
Campbell) (hereinafter cited as 1934 S. 5 Hearings);  1935 H.R. 6906
Hearings 60, 96 (same).  Other parties viewed these proposals in the
same way.  See 1933 S. 1944 Hearings 108 (Dr. James Beal, National
Drug Trade Conf.) ("Section 10 authorizes the Secretary to determine
what added substances in food * * * 'is or may be injurious to
health', and either to prohibit the use of such substances or to limit
the amount which may be present.");  id. at 374 (Statement Covering
Senate Bill 1944, Kentucky State Board of Health (Dec. 1933)) ("(t)he
proposed legislation authorizes the Secretary of Agriculture to
establish, upon expert advice, safe tolerances for added poisons in
food");  id. at 478 (Statement of California Fruit Exchange)
(criticizing S. 1944 on the ground that it vests in the Secretary
"complete authority to establish * * * tolerances").

   /29/ See, e.g., S. 1944, 73d Cong., 1st Sess. Section 10(a) (1933);
 C. Dunn, supra, at 43;  S. 5, 75th Cong., 3d Sess. Section 10(a)
(1938);  Br. in Opp. 8-9.  However, FDA Chief Walter Campbell, who was
involved in the drafting of S. 1944, did not construe this term as
requiring the FDA to establish tolerances.  See 1933 S. 1944 Hearings
13-28, 58-82.  Moreover, following the 1933 Hearings on S. 1944,
Senator Copeland, the sponsor of that bill, submitted a revised bill
(S. 2000, 73d Cong., 2d Sess. (1933)), that substituted the term "is
hereby authorized to" in place of the verb "shall" in Section 10(a) of
S. 1944 without saying that he intended to change the substance of the
bill.  See 1933 S. 1944 Hearings 493-494, 498.  No one who testified
on S. 1944 during the hearings stated that the term "shall" imposed a
mandatory duty on the FDA to adopt tolerances.  S. 5, 75th Cong., 3d
Sess. (1938), also contained the term "shall," but no one in the
House, where this substitution was made, maintained that this term
imposed a mandatory duty on the FDA to promulgate tolerances.  See
pages 32-33, infra.

   /30/ See, e.g., S. 2000, 73d Cong., 2d Sess. Section 10(a) (1934);
S. 2800, 73d Cong., 2d Sess. Section 12(a) (1934);  H.R. 8316, 73d
Cong., 2d Sess. Section 10(a) (1934);  S. 5, 74th Cong., 1st & 2d
Sess. Section 304(a) (1935);  S. 5, 75th Cong., 1st Sess. Section
15(a) (1937);  C. Dunn, supra, at 58, 78, 195, 646.

   /31/ See S. Rep. 493, 73d Cong., 2d Sess. 4 (1934) (accompanying S.
2800);  S. Rep. 361, 74th Cong., 1st Sess. 6 (1935) (accompanying S.
5);  S. Rep. 646, 74th Cong., 1st Sess. 3 (1935) (accompanying S. 5);
H.R. Rep. 2139, 75th Cong., 3d Sess. 6 (1939) (accompanying S. 5);  C.
Dunn, supra, at 125, 249, 536, 554-555, 667, 820;  see also 78 Cong.
Rec. 8956 (1934) (Sen. Copeland).  The bill (S. 5, 75th Cong., 3d
Sess. (1938)) reported in H.R. Rep. 2139, supra, was the one
ultimately adopted by Congress.

   /32/ The original bill submitted by the FDA simply authorized the
agency to promulgate tolerances and did not require the agency to
follow any particular procedure in so doing.  See Sections 10(a) and
23(a) of S. 1944, 73d Cong., 1st Sess. (1933), reprinted at 1933 S.
1944 Hearings 5, 10.  More elaborate administrative procedures were
devised during the course of the hearings in response to criticisms
such as those voiced by the apple industry.  See 78 Cong. Rec. 2728
(1934) (Sen. Copeland);  id. at 4567 (same);  id. at 8956 (same);
Fuchs, The Formulation and Review of Regulations Under the Food, Drug,
and Cosmetic Act, 6 Law & Contemp. Probs. 43, 46-48 (1939).  For
instance, in the bill that ultimately became the FDCA, the version
passed by the Senate (and adopted by the House in a revised form)
created a five member Committee on Public Health to serve in a
consultative fashion and provided for a limited type of administrative
hearing before a tolerance could be promulgated.  See Sections 701-703
of S. 5, 75th Cong., 3d Sess. (1938), reprinted at 1935 H.R. 6906
Hearings 36-37.

   /33/ See, e.g., 1933 S. 1944 Hearings 204-210 (Samuel Fraser, Int'l
Apple Ass'n);  id. at 210-220 (Brief of Int'l Apple Ass'n);  id. at
270 ("Written Analysis of Copeland Bill," submitted by Donald Burke);
id. at 298-299, 301 (John Hall, Flavoring Extract Mfrs. Ass'n);  id.
at 428-429 (J.W. Herbert, Pacific Northwest Fruit & Vegetable
Industry);  id. at 478 (Prepared Statement of California Fruit
Exchange);  1934 S. 2800 Hearings 417-452 (Samuel Fraser);  id. at 220
(Prepared Statement of Flavoring Extract Mfrs.);  1935 S. 5 Hearings
254-276 (Samuel Fraser);  1935 H.R. 6906 Hearings 323-336 (R.G.
Phillips, Int'l Apple Ass'n);  id. at 441-443 (Rep. Buck).

   /34/ H.R. Rep. 2139, 75th Cong., 3d Sess. 9-12 (1938) (describing
revisions);  id. Pt. 2, at 1-4 (Minority Views);  id. at 3-4 (letter
from Secretary of Agriculture Wallace to Rep. Mapes criticizing the
review process);  83 Cong. Rec. 7772 (1938) (Rep. Robertson);  id. at
7775-7776 (Rep. Lea);  id. at 7783 (Rep. Leavy);  id. at 7893 (Rep.
Robertson);  id. at 7894 (Rep. Voorhis);  id. at 7894-7895 (Rep.
Leavy);  see generally id. at 7891-7898 (debate over proposed
amendment to judicial review provisions of the FDCA, Sections 701-703
of S. 5, supra);  Cavers, supra, 6 Law & Contemp. Probs. at 20-21;
see pages 6-7, supra (describing regulatory and judicial review
procedures).  Some members of the House, which imposed these
requirements, stated that they believed these procedures were required
by this Court's then-recent decision in United States v. Morgan, 304
U.S. 1 (1938).  See 83 Cong. Rec. 9096, 9098 (1938) (Rep. Lea).

   /35/ See also 83 Cong. Rec. 7774 (1938) (colloquy between Reps.
Sirovich and Lea);  id. at 7775 (Rep. Lea) ("(i)n this bill we give a
broad extension of authority to the Secretary of Agriculture, and in
that respect it is one of the broadest bills ever passed by this
Congress in ordinary peacetimes");  id. at 7784 (Rep. Coffee)
("(t)here is nothing radical or revolutionary about the sections in S.
5, which authorize the Secretary of Agriculture to issue a regulation
concerning * * * the amount of lead and arsenic which will be
permitted on apples shipped in interstate commerce");  id. at 9097
(Rep. Lea) ("regulations may be established under this bill");  id. at
9100 (Rep. Reece).

   /36/ Walter Campbell made this precise point when he testified
before Congress in 1934.  1934 S. 2800 Hearings 530.  In his words,
the langauge in the pending legislation (that became the FDCA)
(ibid.):

      is the language of the present law.  That language has been
      considered in litigation which was carried to the Supreme Court,
      and has been very exhaustively discussed by that Court.

         Now, one of the concerns that we have is, first, the most
      extensive and most effective protections to the public that can
      be made.  Unquestionably the use of the subjunctive provides
      that.  And, second, to preserve the use of language which has
      already been considered by the Supreme Court.

   /37/ Respondents argue (Br. in Opp. 10) that the FDA's construction
of the FDCA makes Section 406 superfluous, on the ground that Section
701 authorizes the agency to promulgate regulations to enforce the Act
and thus presumably would empower the FDA to establish tolerances in
the absence of Section 406.  But Section 406 does far more than simply
authorize the FDA to establish tolerances;  it also provides that a
food is not adulterated under Section 402(a)(1) if a tolerance is in
effect, even if the FDA could prove in court that the food was
potentially harmful.  Furthermore, the legislative history of the FDCA
shows that Section 406, not Section 701, was designed to provide the
substantive standard by which the FDA was empowered to issue
tolerances.

   /38/ See also Trade Correspondence 5-A (Nov. 5, 1945), reprinted in
1 V. Kleinfield, C. Dunn, & A. Kaplan, supra, at 751 (emphasis added)
("a tolerance may be fixed by regulation");  Trade Correspondence 3-A
(Nov. 5, 1945), reprinted in 1 V. Kleinfield, C. Dunn, & A. Kaplan,
supra, at 750 (stating that the FDA would not take action against
apples and pears containing not more than 7 milligrams of DDT per
kilogram of fruit).

   /39/ The court of appeals also found that its construction of
Section 406 was compelled by the structure of that provision.  Pet.
App. 7a.  But even if the court believed that its own reading of the
statute corresponded with the most refined rules of grammar, that too
is an insufficient reason for refusing to defer to the agency's
interpretation.  Complex regulatory statutes are frequently written in
a language that is all their own, and adherence to the strictest
grammatical standards is not always a reliable way to divine
Congress's intent (see Flora v. United States, 362 U.S. 145, 150
(1960) ("(t)his Court naturally does not review congressional
enactments as a panel of grammarians")).  Congress's use and placement
of the word "shall" therefore simply marks the beginning of the
inquiry, not the end.

   /40/ Section 346a(b) provides in pertinent part (emphasis added):

         The Administrator (of EPA) shall promulgate regulations
      establishing tolerances with respect to the use in or on raw
      agricultural commodities of poisonous or deleterious pesticide
      chemicals and of pesticide chemicals which are not generally
      recognized, among experts qualified by scientific training and
      experience to evaluate the safety of pesticide chemicals, as
      safe for use, to the extent necessary to protect the public
      health.

   /41/ The FDA Commissioner, Charles W. Crawford, stated (Federal
Food, Drug, and Cosmetic Act:  Hearing on H.R. 4277 Before a Subcomm.
of the House Comm. on Interstate and Foreign Commerce, 83d Cong., 1st
Sess. 121 (1953)):

         We have given out so-called informal tolerances on a great
      many of these things, we have freely given that out and if their
      schedules bring those spray residues within those informal
      tolerances there is no basis under the law for us to proceed
      because if we proceed on the other provision of section 402 (21
      U.S.C. 342) -- that is 402(a)(1) (21 U.S.C. 342(a)(1)), we have
      to assume the burden of proving that the quantity of the spray
      residue present in this particular commodity here in and of
      itself may injure the health of consumers and we would not give
      a tentative tolerance at a figure where there was any likelihood
      of our being able to make a case of that kind.

   The National Canners Association wrote to both the House and Senate
committees to express its understanding that Section 408 (21 U.S.C.
346a) would apply only to raw agricultural commodities.  The
Association's letter to the House committee stated (Federal Food,
Drug, and Cosmetic Act:  Hearing on H.R. 7125 Before the House Comm.
on Interstate and Foreign Commerce, 83d Cong., 2d Sess. 31 (1954)
(emphasis added)):

      It is the understanding of the National Canners Association that
      after passage of this bill processed foods will be in exactly
      the same position as before in that tolerances for pesticide
      residues with respect to processed foods may be established
      under section 406 (21 U.S.C. 346) of the Act;  that in the event
      the Secretary acts to establish a tolerance for residues on
      processed foods under section 406 actions for adulteration will
      be taken under section 402(a)(2) but if the Secretary has not
      acted under section 406 any action for adulteration because of
      excessive pesticide residue in the processed food will still be
      taken under section 402(a)(1) (21 U.S.C. 342(a)(1)).  This
      understanding of the canning industry is, we are advised, shared
      by Dr. Miller (i.e., Representative Miller, the sponsor of the
      House bill), by the FDA, and by all others interested in this
      legislation.

   See also Residues of Pesticide Chemicals:  Hearing on S. 2868 and
H.R. 7125 Before the Subcomm. on Health of the Senate Comm. on Labor
and Public Welfare, 83d Cong., 2d Sess. 93 (1954) (NCA letter to the
Senate committee chairman to the same effect).

   /42/ Nor is this the only instance in which the FDA brought its
construction of Sections 402 and 406 to Congress's attention.  In the
hearings preceding the adoption of the Color Additive Amendments of
1960, Pub. L. No. 86-618, 74 Stat. 397 et seq., the FDA submitted a
section-by-section analysis of the bill, stating that Section 102(a)
"makes explicit, with regard to color additives, the interpretation of
the Supreme Court in Flemming * * * that section 406(a) of existing
law -- which authorizes the establishment of tolerances for poisonous
or deleterious substances added to food * * * -- cannot serve as a
basis for allowing the use of coal tar colors." Color Additives:
Hearings on H.R. 7624 and S. 2197 Before the House Comm. on Interstate
and Foreign Commerce, 86th Cong., 2d Sess. 27 (1960) (emphasis added).
 The House Report on the Act quoted the agency's analysis verbatim.
See H.R. Rep. 1761, 86th Cong., 2d Sess. 69 (1960).  In the hearings
on the Food Additives Amendment of 1958, Pub. L. No. 85-929, 72 Stat.
1784 et seq., the agency once again informed Congress of its view on
the meaning of Section 406.  See Food Additives:  Hearings Before a
Subcomm. of the House Comm. on Interstate and Foreign Commerce, 85th
Cong., 2d Sess. 41 (1958) (letter from Secretary of HEW Folsom to Sen.
Harris) ("(a)t present, under section 406(a) of the (FDCA), the
Secretary is authorized to limit the poisonous or deleterious
substances required in the production of food to such extent as he
finds it necessary for the protection of public health").

   /43/ For a sampling of the FDA's enforcement efforts, see, e.g.,
United States v. Boston Farm Center, Inc., supra (FDA obtained an
injunction prohibiting the marketing of aflatoxin-contaminated corn);
Seabrook Int'l Foods, Inc. v. Harris, 501 F. Supp. 1086 (D.D.C. 1980),
aff'd sub nom. Continental Seafoods, Inc. v. Schweiker, 674 F.2d 38
(D.C. Cir. 1982) (FDA issued a prohibition against importation of
salmonella-contaminated Indian shrimp);  United States v. Anderson
Seafoods, Inc., supra (FDA obtained an injunction prohibiting the
marketing of mercury-contaminated swordfish).

   The decided cases, of course, represent only a tiny fraction of the
FDA's use of action levels to prevent the distribution of adulterated
food in interstate and foreign commerce.  Sections 702 and 704 of the
FDCA, 21 U.S.C. 372 and 374, authorize the Commissioner to conduct
inspections and to take and analyze food samples to determine whether
they are adulterated.  Each year, in accordance with instructions
issued to its field offices, the FDA analyzes approximately 10,000
articles of domestically produced and imported food.  The FDA
thereafter recommends judicial enforcement actions only if the agency
cannot obtain voluntary compliance by the person involved.  Litigation
therefore is the last step in the FDA's enforcement efforts and is
necessary only on rare occasions.

   /44/ The court of appeals may have made this assumption because of
its belief that any amount of aflatoxin "may render (food) injurious
to health" under Section 402(a)(1).  Pet. App. 4a.  However, the only
evidence of record on this point shows that food must contain at least
20 ppb aflatoxin in order to present any reasonable possibility of
harm.  See J.A. 193, 194, 225.  Moreover, for certain uses, corn must
contain more than 100 ppb aflatoxin before it may become injurious to
health.  See pages 9-10 note 10, supra.

   /45/ This point is graphically illustrated by the FDA's experience
with formal tolerances for polychlorinated biphenyls (PCBs).  Based on
newly obtained toxicological data, the FDA in April 1977 proposed to
lower the existing tolerance from 5 parts per million (ppm) to 2 ppm
for residues of PCBs in fish, shellfish, and several other classes of
food.  42 Fed. Reg. 17487.  The final rule was promulgated in 1979.
44 Fed. Reg. 38330.  At the request of a fishing industry trade
association, a hearing was held in May 1981.  The FDA issued its
decision in March 1982.  47 Fed. Reg. 10079.  After the agency invited
the submission of other relevant material (ibid.), the final decision
was issued in May 1984.  49 Fed. Reg. 21514.  During all this time,
the 5 ppm tolerance remained in effect, thereby exposing consumers to
levels of PCBs that the FDA considered potentially harmful.  The
entire process of lowering the tolerance for PCBs in fish and
shellfish took seven years, although a comparable amendment of an
action level could have been effected in a relatively brief period.

   /46/ For example, in 1944 the FDA's predecessor agency took only
four months to adopt a tolerance for fluorine spray residues on apples
and pears.  9 Fed. Reg. 4654 (1944) (notice of hearing);  id. at 9754
(proposed regulation);  id. at 11836 (final order).

   /47/ This point is also illustrated by the adoption of formal
tolerances for PCBs in paper materials used in packaging foods.  In
March 1972, the FDA proposed to establish formal tolerances for PCBs
in food and paper food-packaging materials.  37 Fed. Reg. 705.  In
July 1973, the FDA published a final rule based on the proposal.  38
Fed. Reg. 18096.  At the request of several paper industry firms a
public hearing was granted.  40 Fed. Reg. 11563 (1973).  Subsequently,
the FDA's Bureau of Foods and the industry parties reached a proposed
settlement agreement, which was submitted for the Commissioner's
approval in November 1978.  After further proceedings, a revised
settlement agreement was announced in the Federal Register in August
1983.  48 Fed. Reg. 37020.  Thus, the promulgation of a formal
tolerance -- where there was an objection but, by mutual agreement, no
full trial-type hearing -- took more than a decade to complete.

   Respondents suggest (Br. in Opp. 13) that the formal rulemaking
requirements of 21 U.S.C. 371(e) are not burdensome for the agency
because the FDA can invoke the summary judgment procedures upheld in
Weinberger v. Hynson, Westcott & Dunning, Inc., 412 U.S. 609 (1973).
That procedure may alleviate some of the congestion that is likely to
ensue if the court of appeals' judgment is upheld, but it does not
fully remedy the problem.  FDA summary decisions can be, and have
been, set aside by the courts.  See, e.g., Hynson, 412 U.S. at
622-623;  American Cyanamid Co. v. FDA, 606 F.2d 1307 (D.C. Cir.
1979);  Edison Pharmaceutical Co. v. FDA, 513 F.2d 1063 (D.C. Cir.
1975).  Moreover, because the question in a tolerance-setting
proceeding is the appropriateness of the level selected by the FDA,
which requires the agency to consider the overall economic impact of
that level (see 21 C.F.R. 509.6(b)(1);  42 Fed. Reg. 52816 (1977)),
there is no reason to assume that objectors would not be able to raise
genuine and substantial factual issues, which would prevent the FDA
from granting summary judgment.  (Indeed, respondent Public Citizen's
Health Research Group was recently able to raise such issues in the
context of, and to obtain a hearing on, the FDA's final rule
permanently listing a particular color additive for general use in
food and in ingested drugs.  See 40 Fed. Reg. 51145-51146 (1973)
(notice of hearing).) In any event, there is no reason to assume that
the extended litigation that would follow from an affirmance of the
court of appeals' judgment would enhance the FDA's current ability to
protect the public health, and respondents offered no evidence below
that would justify such a conclusion.

   /48/ The FDA action levels to which Section 406 could now apply
are:  aflatoxin, cadmium, crotolaria seeds, mercury,
nitrosodimethylamine (NDMA), paralytic shellfish toxin, polybrominated
biphenyls (PPBs), and PCBs.

   /49/ Moreover, the logic of the court of appeals' decision is not
limited to those substances for which an action level has already been
set but rather extends to the whole universe of added, unavoidable
poisonous or deleterious substances in food.  Many of these substances
may occur only in negligible amounts in a multitude of foods for which
there is no existing action level;  many of these substances, although
undetectable using currently-available analytical methods, may be
found in a variety of foods as such methods become more sensitive;
and many of these substances may yet be undiscovered.  Aflatoxin, for
example, was not discovered until the early 1960s.  J.A. 34.  But
under the court of appeals' interpretation of Section 406, every one
of these substances must be regulated by a formal tolerance, and every
proposed modification of a tolerance must go through the same
prolonged rulemaking process.

                               APPENDIX