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EPA Proposes Regulation of Designated PBT Chemical Substances

On June 21, 2019 the U.S. Environmental Protection Agency (EPA) released a pre-publication copy of a proposed rule under section 6(h) of the Toxic Substances Control Act (TSCA) covering five chemical substances designated as persistent, bioaccumulative, and toxic (PBT).  The substances are:      

    • Decabromodiphenyl ether (DecaBDE)
    • Phenol, isopropylated phosphate (3:1) or PIP (3:1)
    • 2,4,6-tris(tert-butyl)phenol (2,4,6-TTBP)
    • Hexachlorobutadiene (HCBD); and
    • Pentachlorothiophenol (PCTP).

Projected to be final by December 2020 (and take effect 60 days post-finalization) the rule would ban the manufacture, import, processing and distribution in U.S. commerce for many uses of four of the substances and would not regulate the fifth substance.  EPA will seek public comment on the proposal for 60 days following publication in the Federal Register.

Section 6(h) mandates that EPA take expedited action on substances for which the Agency has a reasonable basis to conclude are toxic, and that with respect to persistence and bioaccumulation, score high for one and either high or moderate for the other (pursuant to EPA’s 2012 TSCA “Work Plan”), and for which exposure is likely under the conditions of use.  The statute dictates that EPA reduce exposures to these substances to the “extent practicable,” a phrase being broadly defined in this context. 

A substance-by-substance summary follows.

Hexachlorobutadiene (HCBD)

EPA is proposing no regulatory action for HCBD because the Agency believes that exposures to this substance are already regulated under other environmental regulations such as the Clean Air Act. In addition, EPA believes that human exposure to HCBD is “very limited due in large part to high waste treatment efficiencies achieved by the chemical manufacturers.”

Decabromodiphenyl ether (DecaBDE)

EPA is proposing to ban all manufacture (including import), processing and distribution in commerce of DecaBDE and DecaBDE-containing products or articles except:

    • for use in parts for new aircraft and aerospace vehicles for a period of three years;
    • for use in curtains in the hospitality industry for a period of 18 months;
    • for use in replacement parts for the automotive and aerospace industries; and
    • for products made from recycled plastic that contained DecaBDE before the plastic was recycled, so long as no new DecaBDE was added during the recycling process or to the articles and products made from the recycled plastic.

Phenol, isopropylated phosphate (3:1) or PIP (3:1)

EPA is proposing to ban all processing and distribution in commerce of PIP (3:1) (also known as tris(4-isopropylphenyl) phosphate) and PIP (3:1)-containing products or articles, except for:

    • aviation hydraulic fluid;
    • lubricants and greases; and 
    •  new and replacement parts for automobiles and other motor vehicles, parts to which PIP (3:1) has been added.

The Agency also is proposing to ban all releases of this substance to water during manufacturing, processing, distribution and commercial use. Persons manufacturing, processing, and distributing this substance and products containing this substance would be required to notify their customers of these restrictions.

2,4,6-tris(tert-butyl)phenol (2,4,6-TTBP)

EPA is proposing to ban the distribution in commerce of 2,4,6-TTBP and products containing 2,4,6-TTBP in any container with a volume less than 55 gallons for any use. The proposed rule would also ban the processing and distribution in commerce of 2,4,6-TTBP and products containing 2,4,6-TTBP for use an oil or lubricant additive, regardless of container size.  Specifically, the rule would prevent the use of 2,4,6-TTBP as a fuel additive or fuel injector cleaner by consumers and small commercial operations (e.g., automotive repair shops, marinas).

Pentachlorothiophenol (PCTP)

EPA is proposing to ban the manufacture, import, processing, and distribution in commerce of PCTP, and products containing PCTP unless in concentrations at or below 1% by weight.

EPA will solicit public comments on various aspects of the proposed rule including:

    • “real-world” exposure and use data;
    • potential economic impact of the rule;
    • EPA’s decision to not pursue a systematic review of risk;
    • whether additional time is needed for products to clear the channels of trade;
    •  factors that should be considered in determining if a restriction is “practicable”; and
    • why alternative or substitute chemicals may be impractical

It is critical that manufacturers, importers, processors, distributors and users of these substances submit comments to EPA.

For questions or assistance in preparing comments please contact us:

Herbert Estreicher, Ph.D. (1 202.434.4334),

homas C. Berger (1 202.434.4285),

James G. Votaw (1 202.434.4227),