UNITED STATES SUPREME COURT DECISIONS ON-LINE

The Federal Food, Drug, and Cosmetic Act (Act) provides in 21 U.S.C. § 346 that, when the addition of any poisonous or deleterious substance to food is required in the production thereof or cannot be avoided by good manufacturing practice, 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."

The Food and Drug Administration (FDA), the Secretary's designee for enforcing the Act, has long interpreted the phrase beginning "to such extent" to modify the word "shall," rather than "the quantity therein or thereon," and therefore views the decision whether to promulgate a § 346 regulation (tolerance level) as a determination to be made by the FDA. Rather than setting a tolerance level for aflatoxin, a potent carcinogen that is unavoidably present in some foods, the FDA set an action level of 20 parts per billion (ppb) (an action level assures food producers that the FDA ordinarily will not enforce the Act's general adulteration provisions against them if the quantity of the harmful substance in food is less than a specified quantity). But in 1980, the FDA published a notice in the Federal Register that the Act would not be enforced as to a certain harvest of corn to be used for livestock and poultry feed where it contained no more than 100 ppb. Respondents, two public interest groups and a consumer, brought suit against petitioner Commissioner of Food and Drugs in Federal District Court, alleging that the Act requires the FDA to set a tolerance level for aflatoxin before allowing the shipment of food containing the substance, that, in this case, the FDA had employed insufficient procedures to set the aflatoxin action level even if a tolerance level was not required, and that the FDA's decision to grant the exemption from the action level violated the Act and the FDA's own regulations. Adopting the FDA's longstanding interpretation of § 346 as giving it discretion whether to promulgate a tolerance level, the District Court, on a motion for summary judgment, ruled that the FDA need not establish a tolerance level for aflatoxin before allowing the shipment of the aflatoxin-tainted corn. The Court of Appeals clubjuris

Page 476 U. S. 975

reversed, holding that the FDA's interpretation of § 346 conflicted with its plain language.

Held: In light of § 346's inherent ambiguity, the FDA's interpretation of the provision is sufficiently rational to preclude a court from substituting its judgment for that of the FDA. The legislative history is equally ambiguous, and provides no support for assertions that the FDA's interpretation is insufficiently rational to warrant this Court's deference. Pp. 476 U. S. 979-983.

244 U.S.App.D.C. 279, 757 F.2d 354, reversed and remanded.

O'CONNOR, J., delivered the opinion of the Court, in which BURGER, C.J.,and BRENNAN, WHITE, MARSHALL, BLACKMUN, POWELL, and REHNQUIST, JJ., joined. STEVENS, J., filed a dissenting opinion, post, p. 984.