EPA Publishes a TSCA "Top 10" List of Sorts: What Chemicals Made the Cut?

EPA has successfully met one of the first major milestone of the Agency's First Year Implementation Plan for the Frank R. Lautenberg Chemical Safety for the 21st Century Act. On November 29, 2016, EPA published its initial list of 10 "high priority" chemical substances from its 2014 Update to the Work Plan for Chemical Assessments (i.e., "Work Plan Chemicals") that will undergo risk evaluations under deadlines established by the 2016 amendments to the Toxic Substances Control Act (TSCA). The substances EPA listed are:

Background

Some years prior to the 2016 amendments to TSCA, EPA had embarked on a plan to identify and review information concerning the health and environmental effects of chemical substances in use in the US. Ultimately, the Agency intended to assess the risks presented by the substances and, depending on the outcome of the assessments, take regulatory actions as appropriate. In doing so, EPA hoped to shake-off the widely-held perception that the Agency could not effectively review and regulate chemicals under the 40-year-old legislation. Thus, EPA had unveiled its initial sorting and prioritization method and subsequently identified a set of "Work Plan" chemicals for further assessment. The Work Plan list was originally released in 2012 and was updated in 2014. Some of the criteria important to EPA in selecting chemicals for the Work Plan included: potential to be of concern to children's health; neurotoxicity; persistence, bioaccumulation, and toxicity (PBT); carcinogenicity; use in children's products; and detection in biomonitoring programs or in drinking water.

In the 2016 amendments to TSCA Congress acknowledged and accommodated the Agency's progress to date on developing the Work Plan list while at the same time imposing additional requirements that EPA must eventually prioritize all substances that are actively in commerce and undertake risk evaluations for those substances which "may present an unreasonable risk" to health or the environment. Under Section 6(b)(1)(A) of the amended TSCA, EPA is to consider a number of factors in prioritizing chemicals as either "high" or "low" priority:

The process to designate the priority of chemical substances shall include a consideration of the hazard and exposure potential of a chemical substance or a category of chemical substances (including consideration of persistence and bioaccumulation, potentially exposed or susceptible subpopulations and storage near significant sources of drinking water), the conditions of use or significant changes in the conditions of use of the chemical substance, and the volume or significant changes in the volume of the chemical substance manufactured or processed. (emphasis added)

The amended law defines "high-priority" substances as those that "may present an unreasonable risk of injury to health or the environment because of a potential hazard and a potential route of exposure ... including an unreasonable risk to a potentially exposed or susceptible subpopulation" (e.g., infants, children, pregnant women, workers, or the elderly). Section 6(b)(1)(B)(i).

In accordance with additional guidance in the Act, EPA has stated its intent to accord preference to those substances with persistence and bioaccumulation scores of 3 (using EPA's Work Plan chemicals scoring system), and known human carcinogens with high acute or chronic toxicity.¹ Ultimately, the statute requires that 50% of the high priority chemicals selected for risk evaluations must come from the 2014 Work Plan, until the approximately 90-chemicals list is depleted. Among other near-term priorities for the Agency, EPA must issue by June 2017 final procedural regulations that will address how future prioritization exercises will be conducted, and how its risk evaluation process will be managed.²

EPA's "High Priority" List Contains Few Surprises

Many of the substances on EPA's initial list of "high priority" substances come as no surprise. At the time of the TSCA amendments, EPA had already initiated risk assessments for approximately a dozen Work Plan substances and EPA has selected five of its first 10 "high priority" substances from the shorter list of those substances for which EPA has completed risk assessments: 1-Bromopropane, 1,4-Dioxane, Methylene Chloride, and N-Methylpyrrolidone (NMP), Trichloroethylene (TCE). Both 1-Bromopropane and 1,4-Dioxane were likely candidates, because they have a hazard score of 3, are possible carcinogens, are widely used in consumer products, have high reported releases to the environment, and have been detected in drinking water or groundwater. In contrast, Methylene Chloride and NMP, which have both low environmental persistence and potential for bioaccumulation, were less likely choices—especially considering that EPA recently submitted proposed regulations to OMB for review that will likely propose limits on certain uses of those two substances pursuant to Section 6(a) of TSCA. EPA choice of trichloroethylene (TCE) is similarly somewhat surprising, given that EPA has also undertaken a rulemaking with respect to TCE under TSCA Section 6(a) and the Notice of Proposed Rulemaking has been under review at OMB for some time and is projected to be published in the Federal Register in December. This strongly suggests there are uses for these thee substances that remain of concern to EPA and that fall outside of the scope of the proposed rules EPA already has submitted to OMB for review. It also might be the case that Agency officials, in view of the impending change of Administrations, want to provide some "insurance" through these particular listings and provide the additional momentum that can be leveraged by NGOs who can point to the new statutory deadlines should the pending proposals get stalled (or derailed) along the way.

Carbon tetrachloride is a listing that is somewhat curious. Carbon tetrachloride has a hazard score of 3, is carcinogenic, was widely used in consumer products, has high reported releases to the environment, is highly persistent, and has been detected in drinking water supplies. Nevertheless, the major consumer uses in the US have largely ceased, maximum concentration limits have been established for drinking water, and there are workplace regulations governing its use and limiting worker exposures.

In contrast, EPA's selection of asbestos is not at all surprising, given that Senator Boxer (D-Calif) seemed willing to torpedo the TSCA amendments because asbestos was not singled out by name in the legislation at the time when the amendments were coming up for a vote in the Senate. The asbestos listing also provides the Agency the perfect opportunity to truly test whether the recent amendments to the statute will finally enable EPA to more readily address a substance that was the target of restrictions in a TSCA Section 6 rulemaking that was successfully challenged in federal court a quarter century ago.³

EPA's choice of the Cyclic Aliphatic Bromides Cluster of substances is also no surprise. These substances are among a number of flame retardant "clusters" of concern to EPA, this one including chemically- similar flame retardants such as Hexabromocyclododecane (HBCD). HBCB has a hazard score of 3, environmental persistence and a high potential for bioaccumulation and a history of use in consumer products with. EPA also published an Initial Assessment for this group of substances in August 2015.

Pigment Violet 29 and tetrachloroethylene are not unexpected choices given they both have properties that meet many—if not all—of the factors Congress set forth for selection to the "high priority" list. Pigment Violet 29 is widely used in consumer products, has high environmental persistence, toxicity to aquatic species, and hazard and exposure scores of 3. Tetrachloroethylene (PERC) has similar properties, is a probable human carcinogen and has also been detected in biomonitoring programs and in drinking water supplies.

EPA's "High Priority" List Partially In Line With What NGOs Had Proposed

Prior to EPA's announcement, several NGOs weighed in on what chemical substances EPA should slate for being among the first 10 identified for review. Safer Chemicals Healthy Families sent a letter to the EPA Administrator in August that recommended the following chemicals, of which the five listed in bold, below, made the cut: