On November 24, 2023, EPA released a proposed rule to revise the final rules for decabromodiphenyl ether (“decaBDE”) and phenol, isopropylated phosphate (3:1) (“PIP (3:1)”), two persistent, bioaccumulative, and toxic substances (PBTs) subject to regulation under section 6 of the Toxic Substances Control Act (TSCA).

Section 6(h) of TSCA (as amended by the Lautenberg Amendments in 2016) required EPA to take expedited action to complete TSCA section 6(a) rules on certain PBTs.  In January 2021, EPA released final rules for decaBDE, PIP (3:1), and three other PBTs.  The final rules for decaBDE and PIP (3:1) generally prohibit their manufacture, processing, and use beginning in March 2021, though the rules contained phased-in prohibitions and exclusions for certain uses; EPA has extended certain phased-in prohibitions for PIP (3:1) multiple times since.

In light of new information and the Agency’s reinterpretation of the directive in TSCA section 6(h)(4) to “reduce exposures to the substance to the extent practicable,” EPA is proposing revisions to the final rules for decaBDE and PIP (3:1).  For decaBDE, the proposed revisions include:

The proposed revisions to the PBT rule for PIP (3:1) include:

In the proposed rule, EPA states that the Agency is not reconsidering the final rules for the other three PBTs–2,4,6-TTBP, HCBD, and PCTP–subject to final rules in January 2021.

According to EPA, decaBDE is a flame retardant that is used in textiles, plastics, adhesives, and polyurethane foam, and PIP (3:1) is a flame retardant, a plasticizer, and an anti-compressibility and anti-wear additive used in lubricants, hydraulic fluids, and in the manufacture of other compounds.