The US EPA is considering 15 substances for the next round of risk evaluation under TSCA, with plans to initiate the prioritisation process for five of them before the end of the year, the agency has confirmed.
This would be the first group of substances to be prioritised since the agency selected 20 high-priority chemicals in late 2019. The candidate list obtained by Chemical Watch highlights the type of data-rich substances the agency has said it will look to next as it moves to a staggered annual process for scrutinising five to six existing chemicals each year.
Under consideration are 13 substances from the TSCA work plan, plus the highly toxic fluorine compound precursor hydrogen fluoride and tyre additive 6PPD (see box). The majority of them are used in the production of plastics and rubber products, and many have applications that could impact a wide range of sectors, from refrigeration to mining to metal finishing.
The agency said it met last week with representatives from industry, NGOs, labour groups, as well as other federal agencies and state and local governments to discuss the list of candidate substances.
Through these discussions, the agency aims to "obtain needed information on potential uses, exposures, hazard and industry practices much earlier in the prioritisation and risk evaluation process", it said.
The EPA said it plans to select five chemicals "later this calendar year" to initiate the formal, nine-to-twelve-month prioritisation process. Substances designated as high priorities are subject to risk evaluation and subsequent risk management rulemaking if the agency determines they pose an ‘unreasonable risk’.
Fifteen candidate substances
The substances are:
- acetaldehyde;
- acrylonitrile;
- benzenamine;
- benzene;
- bisphenol A (BPA);
- ethylbenzene;
- naphthalene;
- styrene;
- tribromomethane;
- triglycidyl isocyanurate;
- vinyl chloride;
- hydrogen fluoride;
- 4,4’methylene bis(2-chloroaniline);
- 4-tert-octylphenol(4-(1,1,3,3-tetramethylbutyle)-phenol; and
- n-(1,3-dimethylbutyl)-N′-phenyl-p-phenylenediamine (6PPD).
Data-rich substances
"These chemicals were selected in part because data is generally available on all of them," the EPA told Chemical Watch. But the agency said it will also consider any "appropriate and timely" action to gather this.
That means the next round of substances may rely more on the EPA’s section 8 authority to call in existing information, and less on its section 4 authority to order health and safety testing.
The search for the next round substances for review comes roughly seven months after the agency said it would "reimagine" the TSCA risk evaluation process in light of budgetary constraints and insufficient staffing.
It already faces one lawsuit for failing to meet its statutory deadlines to complete any of the previous 20 reviews or manufacturer-requested risk evaluations for two phthalates. Another lawsuit could soon follow over its slow pace on the two MRREs.
Last week, the EPA signalled its first concrete timeline for those overdue reviews, indicating plans to publish a draft evaluation for TCEP in December.
Plastic chemicals under scrutiny
Most of the 15 substances under consideration are used in the production of polyethylene, polystyrene and other synthetic compounds, following pressure from NGOs to ban harmful chemicals found in plastics.
Candidates include several high-profile chemicals like vinyl chloride, which garnered national headlines after a train carrying the colourless compound derailed in Ohio in February; as well as benzene and BPA, both of which face scrutiny from the US Food and Drug Administration (FDA) for applications related to cosmetics or food packaging.
Other substances on the shortlist for prioritisation include hydrogen fluoride, used to make refrigerants and in etching glass and metal, and the solvent tribromomethane (bromoform), used for mineral ore separation in geologic tests. Triglycidyl isocyanurate (TGIC) is used in plastics and also to make polyester powder coatings, or paints, used in metal finishing.
Another substance, 6PPD, has recently drawn the attention of regulators in California and Washington for its effects on salmon. While those states are currently examining the compound’s use in vehicle tyres, it is also used to stabilise other rubber products, including plumbing seals.
Earthjustice filed a TSCA section 21 citizen petition on behalf of three indigenous tribes earlier this year seeking a prohibition on 6PPD. The EPA has until 30 October to respond to the request.