TSCA Prioritization: What is it good for?

Written on: June 1, 2019 by Dr. Steve Bennett

The U.S. Environmental Protection Agency (EPA) recently designated 20 High Priority chemicals under the Toxic Substances Control Act (TSCA).1 This is the latest implementation step in the multi-year process of changes required by the amendments to TSCA by the Frank R. Lautenberg Chemical Safety Act of 2016 signed into law by then President Obama. So, what does prioritization mean? What, if anything, should interested parties do?

The High Priority designation is a new process within the reformed TSCA in which EPA identifies potential chemicals for risk evaluation. Chemicals designated as High Priority are identified by using (1) hazard and exposure potential or a category of chemical (including consideration of persistence and bioaccumulation, potentially exposed or susceptible subpopulations and storage near significant sources of drinking water), (2) the conditions of use or significant changes in the conditions of use of the chemical and (3) the volume or significant changes in the volume of the chemical manufactured or processed. High Priority chemicals can also be selected from the remaining chemicals on EPA’s 2014 Work Plan.

It is important to note that the High Priority designation is not a finding of unreasonable risk. Rather, it means that the identified chemical shall have its conditions of use evaluated for determination of unreasonable risk. It is critical that the information EPA has on a chemical is accurate and complete to ensure robust decisions. Incomplete or missing information will undoubtably lead to less than ideal decisions or excessively conservative risk estimates, neither of which are in the best interest of EPA or the industry. In addition to leading to robust and defensible decisions, comprehensive information will allow EPA to focus resources effectively and appropriately.

EPA is required to select at least 50% of the High Priority chemicals from the 2014 Work Plan, which uses hazard, exposure and a persistent and bioaccumulation screening criterion, until that list is depleted. This time, EPA identified all 20 High Priority chemicals exclusively from the 2014 Work Plan—a prudent decision at this time, but not one to expect for future High Priority designations since available screening tools will likely improve. While the information gathered in 2014 was as accurate and complete as possible at that time, it has not been significantly updated since, and, in some cases, may be based upon relatively old information.

Many of the 20 High Priority chemicals have experienced considerable scrutiny—the phthalates come to mind—and market usage has shifted noticeably for these chemicals. It would certainly benefit interested parties to provide relevant information that can help fill any data gaps, and to reflect any changes in the conditions of use or markets since the original identification. Interested parties should provide information to EPA as an individual company via a trade association or consortium.

EPA will utilize this information to formally designate a chemical as High Priority. This activity officially starts the three-year clock to complete the risk evaluation for all the conditions of use of the chemical. If any of the conditions of use pose an unreasonable risk during evaluation, the chemical will move to risk management. Alternatively, the evaluation can show that no unreasonable risk is identified, as is the case with the first draft risk evaluation of Pigment Violet 29. Risk management will ascertain if the condition(s) of use can have the unreasonable risk mitigated through label guidance, personal protective equipment or a wide range of restriction options to include prohibitions of use.

A couple of chemicals on the High Priority list deserve special attention and interested parties will very likely provide information to assist EPA in their data gathering efforts, specifically HHCB (galaxolide) and trans-1,2-dichloroehtylene.
HHCB is particularly interesting because this common fragrance component was the first completed risk assessment of the 2014 Work Plan chemicals.2 The previous risk assessment focused on the human health impacts, of which it found none, but did note the “inability to assess potential risks to terrestrial invertebrates and plants is a major uncertainty.” Therefore, HHCB will most likely undergo an updated environmental assessment to address these concerns.

Trans-1,2-dichloroethylene has been living on borrowed time since it was expected to be evaluated within the First Ten Chemicals currently under evaluation—many of which are also chlorinated solvents. Interested parties should carefully consider providing information to EPA regarding the conditions of use, markets of use and other stewardship activities of trans-1,2-dichloroethylene. There may also be interest in eliciting ideas from EPA’s recent proposal for a Certification and Limited Access Program for Commercial Paint and Coating Removal uses of methylene chloride.3
In conjunction with announcing the 20 High Priority chemicals, EPA also announced the first 20 Low Priority chemicals. These chemicals were identified primarily from EPA’s Safer Chemical Ingredient List (SCIL)4 and mostly indicate that all conditions of use do not present unreasonable risk. Similarly, interested parties are encouraged to provide information to EPA supporting (or refuting) this designation. If a chemical is designated as Low Priority, it would be of considerable interest for formulators and manufacturers to utilize this chemical.

Considering all of this, interested parties should carefully review the list of 20 High Priority and 20 Low Priority chemicals and submit relevant information such as the current uses, hazards and exposure information for these chemicals. There is little doubt that several chemicals in these two lists are going to be of interest to the aerosol industry—and likely of direct interest to you. You are encouraged to determine if and how to best submit relevant information to EPA to assist in making appropriate designations. SPRAY