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Assessing and Managing Chemicals under TSCA

TSCA Section 5(b)(4) Concern List

Section 5(b)(4) of the Toxic Substances Control Act authorizes the Administrator to compile and keep current a list of chemical substances with respect to which the Administrator finds that the manufacture, processing, distribution in commerce, use, or disposal, or any combination of such activities, presents or may present an unreasonable risk of injury to health or the environment.

The list of chemicals is to be compiled and kept current through rulemaking proceedings with opportunity for notice and comment.  This includes an opportunity for the oral presentation of data, views, or arguments, in addition to an opportunity to make written submissions. These procedures apply to rules listing chemicals, as well as to the substantive amendment or repeal of such rules.

Before making the finding that activities with respect to a particular chemical substance present or may present unreasonable risk, the Administrator is directed to consider all relevant factors, including the effects of the chemical substance on health and the environment, and the magnitude of human and environmental exposure to the substance.

In prescribing a rule which lists any chemical substance, the Administrator shall also identify those uses, if any, which the Administrator determines, by rule, would constitute a significant new use of the substance. Any such determination would be under TSCA section 5(a)(2).

If a chemical substance is subject to a rule promulgated under TSCA section 5(b)(4), EPA can, by rule, require a small manufacturer or processor of that chemical to submit reports under TSCA section 8(a) from which small businesses are otherwise exempt. Also, anyone who exports or intends to export a chemical substance that is the subject of a proposed TSCA section 5(b)(4) rule are subject to the export notification provisions of TSCA section 12(b).