By announcing the first 10 chemicals to be evaluated under the revised Toxic Substances Control Act (TSCA) the EPA has provided a window into the criteria they will use to identify candidates for inclusion in the process going forward. Within six months they must release scoping documents that include the hazard(s), exposure(s), conditions of use and the potentially exposed or susceptible subpopulation(s) the Agency plans to consider for the evaluation. The risk evaluations must be completed within three years, and if the Agency determines that a chemical presents an unreasonable risk it must mitigate it within the two subsequent years.
• Carbon Tetrachloride
• Cyclic Aliphatic Bromide Cluster
• Methylene Chloride
• Pigment Violet 29
Although the assessments must be conducted under the auspices of the revised TSCA the EPA has a “running start” as most of the substances had already been assessed or were in some phase of the process under the old TSCA Work Plan:
Completed Problem Formulation and Initial Assessment
Cyclic Aliphatic Bromides Cluster
What about the others?
Asbestos is a known carcinogen. It is also a legacy issue as the first attempt by the Agency to regulate it under the old TSCA law was famously unsuccessful providing one of the main arguments for TSCA reform. Since they are classified as probable human carcinogens and are manufactured in high volumes Carbon Tetrachloride (CCl4) and Tetrachloroethylene (TETCE) would seem to be logical choices for inclusion in the list. The exposure rationale also states that there are high releases to the environment (multiple compartments) and the substances are “present in biomonitoring.” It is instructive that biomonitoring is being included as a rationale to trigger exposure based concerns, as the last report from the Centers for Disease Control and Prevention (CDC) listed blood levels of 0.048 ng/mL for TETCE and ≤ 0.01 ng/mL for CCl4 (ng/ml = ppb).
Pigment Violet 29 is not a particularly high volume chemical (2012 CDR reported it at 236000 kg) however it is used in consumer products which may explain its inclusion in the list. The EPA states that the hazard is aquatic toxicity with “moderate” releases to the environment. The Agency’s PBT Profiler (which uses the Agency’s ECOSAR* model for aquatic toxicity estimation) does suggest that the substance is persistent, but not particularly bioaccumulative or toxic. As it was registered in the 100-1000 MT/year volume band for REACH a wealth of actual and read-across data is available.
*The ECOSAR model estimates the acute and chronic toxicity of chemicals discharged into water.
If you manufacture, import or use any of these substances either alone or in a mixture, it is imperative to understand all potential exposures and releases from your or your customer’s operations during the lifecycle of your product. This first batch of substances also begins to reveal the concerns that may drive future nominations (potentially including biomonitoring). It also provides industry with the opportunity to use all available tools to critically evaluate the substances in their portfolios (manufactured and used) against these criteria of concern and proactively develop a strategy for future action.
Critical Path Services can help you determine what your company’s vulnerabilities may be under the new TSCA regulation. We can also provide your company with periodic TSCA updates and assist you in positioning your company to address future regulatory requirements. Critical Path Services can provide representatives of your company with a free consultation to talk you through the major changes enacted by the new law and how these changes could affect your business.
References and Related Documents
Assessments for TSCA Work Plan Chemicals These assessment documents provide the rationale for choosing the substances for review.
CDC National Biomonitoring Program
CDC Biomonitoring Summary ECHA Data for Pigment Violet 29