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Different Stroke for Different Agencies: What’s The Latest With 1,4-Dioxane?

On June, 28, 2019, the US Environmental Protection Agency released a draft risk evaluation for 1,4-dioxane, concluding that the chemical poses no unreasonable risk to the environment and no unreasonable risks to occupational non-users. Meanwhile, the California Department of Toxic Substances Control (DTSC) has identified 1,4-dioxane in personal care and cleaning products as warranting further review and possible identification as Priority Products under the agency’s Safer Consumer Products (SCP) Regulation. DTSC also is seeking input on a proposed 1 ppm Alternatives Analysis Threshold under the SCP Regulation, a value that would trigger a number of obligations under the program; product manufacturer groups have challenged that proposed value as arbitrary and unworkable.  And the New York state legislature has passed a bill banning the chemical in cleaning and personal care products except in trace amounts.

1,4-dioxane is a solvent used in a variety of applications, including the manufacture of other chemicals and degreasing operations. It also can be formed as a byproduct during the production of certain types of surfactants used in personal care and cleaning products. The chemical is considered a probable human carcinogen by a number of agencies.

EPA’s draft risk assessment, conducted pursuant to the federal Toxic Substances Control Act (TSCA), has been criticized for, among other reasons, being overly narrow in scope since it did not address the chemical’s presence in consumer products. The American Cleaning Institute and the Grocery Manufacturers Association, aiming to leverage TSCA’s federal preemption provision, have asked US EPA to expand the scope of its assessment to stop inconsistent state level regulation of the chemical.

Indeed, a patchwork of inconsistent state regulation is a nightmare for manufacturers of chemicals and consumer products. And, unfortunately, state level chemical regulation is not always based on rigorous science.

TSCA’s federal preemption provisions, developed as part of the 2016 TSCA amendments, represent a compromise balance between the need for nationally uniform standards and state’s rights.  In short, where EPA has determined that a substance poses no unreasonable risk and does not require regulation, then a state may not implement regulation of that chemical in a manner that contradicts EPA’s finding. Notably, the scope of this federal preemption of state regulation is only as broad as EPA’s own findings – meaning, here, that EPA’s exclusion of consumer products in its assessment would make state regulation fair game.

August 30, 2019 was the end of the comment period on EPA’s draft assessment.

Grimaldi Law Offices has been advising clients for over 20 years on chemical and product regulation. For knowledgeable advice and in-depth analysis on your chemical regulatory compliance obligations, contact Grimaldi Law Offices at (415) 463-5186 or email us at [email protected].

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Ms. Grimaldi maintains a diverse environmental law practice focusing on chemical and product regulation and litigation defense. Her practice areas include Proposition 65, California's Safer Consumer Products Regulations, California's Rigid Plastic Packaging Container Act and the federal Toxic Substances Control Act. Ms. Grimaldi graduated from the University of California Hastings College of the Law magna cum laude and holds a Bachelor of Science Degree in Bacteriology from University of California, Davis. Prior to attending law school, she worked as a research assistant in laboratories at the University of California, San Francisco Cancer Research Institute and at the University of California, San Francisco School of Medicine.