The Toxic Substances Control Act (TSCA) has long provided EPA with authority to review new chemical substances in a gatekeeper role as such substances enter U.S. commerce. Through amendments in 2016, EPA was also given the authority to evaluate selected existing chemical substances using a three-step framework (explained in further detail here). There are a few dozen substances in the pipeline now, with the first ten substances almost at the end of a long process that will culminate in substance-specific rules. Around the fifth anniversary of the TSCA amendments later this year, the first round of risk management rules should be proposed. These risk management rules could have significant impacts on manufacturers that use the substances in question, and will provide insight on EPA’s approach to such rules going forward.

TSCA Evaluation of Existing Chemical Substances

The three-step process for evaluating existing chemical substances first identifies substances for further study, then evaluates risks posed by those substances, and finally culminates with a risk management rule to mitigate the risks that have been identified:

1) Prioritization: Could this substance pose an unreasonable risk to human health or the environment?  

This is an initial screening step that results in the designation of chemicals as “high priority” for further study or “low priority” and not slated for further study at this time.

There are no substances in the “prioritization” step now. As additional substances move through the pipeline, additional substances will be prioritized, as TSCA requires EPA to have twenty risk evaluations underway at any one time.

2) Risk Evaluation: Does this substance actually pose an unreasonable risk to human health or the environment? 

The 2016 TSCA amendments directed EPA to identify a slate of ten substances that would skip the prioritization step and proceed directly to the risk evaluation step (as we discussed when risk evaluations began in the summer of 2017).  Final risk evaluations have now been completed for each of the first ten substances, and some unreasonable risks to human health and/or the environment were identified for all of them.

Some of the risks identified by EPA include:

• Tetrachloroethylene (perchloroethylene): Unreasonable risks to workers, occupational non-users, consumers and bystanders from 59 conditions of use, including all consumer uses (e.g., automotive care products like brake cleaners, lubricants/greases).
• Carbon Tetrachloride: Unreasonable occupational risks from 13 conditions of use, including processing the chemical as a reactant or intermediate and a variety of other industrial and commercial applications, but no unreasonable risks from two conditions of use (processing as a reactant in reactive ion etching and in distribution in commerce).
• Cyclic Aliphatic Bromide Cluster (HBCD): Unreasonable risks to the environment from six out of 12 conditions of use, and unreasonable risks to workers and occupational non-users from the use of HBCD as a flame retardant in building and construction materials. EPA did not find unreasonable risks to the general population or consumers.

EPA identified the next 20 high-priority substances in 2019 and risk evaluations are underway now. These “next 20” substances include seven chlorinated solvents, five phthalates, three halogenated flame retardants, and five other substances (notably including formaldehyde).  EPA’s website includes a regularly-updated list of all the chemicals undergoing risk evaluation, together with links to dockets providing additional information.

3) Risk Management: How can the risks associated with this substance be managed? 

EPA is required to issue a proposed risk management rule within one year after completing the risk evaluation, and issue the final risk evaluation rule within two years (with the possibility for a two-year extension). Therefore, we would expect to see proposed risk evaluations for many of the first ten substances in the summer and fall of this year. Stakeholders will have an opportunity to submit comments on each of the proposed risk management rules.

When crafting each risk management rule, EPA is directed to consider economic and practical factors, including economic consequences and the beneficial uses of the chemical substance. In other words, where risk evaluations identified conditions of use that did not present unreasonable risk, we might expect EPA to allow such uses to continue.

What’s Next?

Stay tuned for proposed risk management rules, and associated comments and litigation arguing that the rules go too far or not far enough. It is also possible that the change in administration will cause EPA to revisit some of the first ten substances with supplemental risk evaluations. For example, stakeholders have argued that EPA’s risk evaluation on asbestos should have included more analysis of legacy use and disposal not originally considered.  EPA has a busy 2021 ahead.