TSCA Tuesday: Final Risk Evaluation, Updates for 2 PBTs

On November 13, 2024, US EPA announced the final revised unreasonable risk determination for the substance 1,4-dioxane, which is used primarily as a solvent.

US EPA has determined that 1,4-dioxane poses an unreasonable risk to health. The Agency found that workers and occupational non-users (ONU) face cancer and non-cancer risks from inhalation and dermal exposure of 1,4-dioxane. 

For the general population, EPA finds there is a cancer risk associated with exposure to 1,4-dioxane in drinking water sourced from surface water contaminated with industrial discharges and drain disposal of consumer products contaminated with 1,4-dioxane generated as a byproduct.  

Now that a determination of unreasonable risk has been made, EPA must follow up by addressing the risk(s) through measures such as workplace protections and/or restrictions or prohibition on one or more uses of the 1,4-dioxane. 

See the risk evaluation: Final Revised Risk Evaluation for 1,4-dioxane 

After finalizing new requirements for five persistent, bioaccumulative, and toxic (PBT) substances in 2021, EPA received additional comments about the rulemaking from stakeholders in impacted industries. 

Those comments led EPA to revise the requirements for two of the five PBTs—decabromodiphenyl ether (decaBDE) and phenol, isopropylated phosphate (3:1) or "PIP 3:1."  The rule does not change any regulations related to the other three PBTs covered in the 2021 Final Rule. 

The agency proposed revisions one year ago, in November 2023, and has now finalized a rule for publication in the Federal Register on November 19, 2024. The Final Rule will take effect 60 days after it is published. 

A pre-publication copy of the Final Rule is available here. 

For decaBDE, the Final Rule: 

• Requires the use of PPE in domestic manufacturing and processing.
• Requires labeling on plastic shipping pallets known to contain decaBDE. 
• Prohibits releases to water from activities involving decaBDE.
• Extends the compliance date for phasing-out use of the chemical to insulate nuclear power plant wires and cables (and add export related export notification requirements.

For PIP 3:1, the Final Rule: 

• Requires the use of PPE in domestic manufacturing and processing.
• Phases-in prohibitions on processing distribution for certain uses. 
• Adds new exclusions concerning wire harnesses and electric circuit boards.
• Introduces a 5-year compliance timeframe for the ban on processing and distribution to allow for use of PIP 3:1 in certain pesticide products.

Tags: EPA, TSCA