Exactly three months from the date the U.S. Environmental Protection Agency (EPA) Office of Pollution Prevention and Toxics (OPPT) announced its Toxic Substances Control Act (TSCA) Work Plan initiative, EPA on June 1 announced an additional 18 chemicals scheduled for assessment during 2013 and 2014. EPA states that it selected the chemicals for a variety of reasons, similar to those it used to identify the seven Work Plan chemicals to assess in 2012. The chemicals span the range of the Work Plan screening criteria, including chemicals associated with specific hazards such as potential carcinogenicity or reproductive or developmental toxicity; chemicals presenting persistent, bioaccumulative, and toxic (PBT) potential; and chemicals found in biomonitoring or reported in consumer products. EPA notes that some of the chemicals, such as the five chlorinated hydrocarbons, the three flame retardants, and the four fragrance chemicals, may present an effective opportunity to assess groups of related chemicals together.
Chemicals Selected for Risk Assessment in 2013 and 2014
The 18 chemicals are:
- Five Chlorinated Hydrocarbons:
- trans-1-2-Dichloroethylene; and
- Three Flame Retardants:
- Bis(2-Ethylhexyl)-3,4,5,6-tetrabromophthalate (TBPH);
- 2-Ethylhexyl-2,3,4,5-tetrabromobenzoate (TBB); and
- Tris(2-chloroethyl)phosphate (TCEP)
- Four Fragrance Chemicals:
- Ethanone, 1-(1,2,3,4,5,6,7,8-octahydro- 2,3,8,8-tetramethyl-2-naphthalenyl)-;
- Ethanone, 1-(1,2,3,4,5,6,7,8-octahydro- 2,3,5,5-tetramethyl-2-naphthalenyl)-;
- Ethanone, 1-(1,2,3,5,6,7,8,8a-octahydro- 2,3,8,8-tetramethyl-2-naphthalenyl)-; and
- Ethanone, 1-(1,2,3,4,6,7,8,8a-octahydro- 2,3,8,8-tetramethyl-2-naphthalenyl)-
- P,p'-Oxybis(benzenesulfonyl hydrazide); and
- Octamethylcyclotetrasiloxane (D4).
According to EPA, in conducting risk assessments on these 18 chemicals, it will use information available through the data sources cited in the TSCA Work Plan Chemicals Methods Document, as well as other sources. EPA states that it 'would welcome the submission of additional relevant information on these chemicals, such as unpublished studies not already available through the existing literature, or information on uses and potential exposures.' Any relevant information to be included in the review process should be submitted by August 31, 2012. According to EPA, it will post the draft risk assessments for public review and comment as they are completed. More information is available online.
How Did EPA Select the TSCA Work Plan Chemicals?
In September 2011, EPA announced a new approach for identifying priority chemicals for review and assessment under TSCA. EPA conducted an online discussion forum and webinar to gather stakeholder input on proposed criteria and data sources to be used for identifying chemicals for further assessment. More information is available in our September 8, 2011, memorandum, which is available online.
According to EPA, Step 1 of the process it adopted emphasized focusing on chemicals meeting one or more of the following factors:
- Potentially of concern to children's health;
- Probable or known carcinogens;
- Used in children's products;
- Detected in biomonitoring programs, or, a newly added factor; and
- Neurotoxic effects.
EPA also made adjustments to the second stage of its process and developed a hazard, exposure, and persistence/bioaccumulation ranking system to score and screen the chemicals into four priority bins (high, moderate, low, or chemicals that could not be scored, but may be candidates for information gathering). An outline of the scoring and screening system can be found in the TSCA Work Plan Chemicals document at the link above.
Using this process, EPA identified 83 chemicals as candidates for risk assessment in the next several years, as they all scored high in this screening process based on their combined hazard, exposure, and persistence and bioaccumulation characteristics. In identifying a smaller set of chemicals for work in any given year, EPA states that it considers a number of factors:
- Whether the chemical was identified as a 'High' ranking chemical;
- Whether the chemical reflects more than one of the factors identified in Step 1 (for example, chemicals that were identified as a potential concern for children's health and also were PBT) and whether each of the factors was covered by the set of chemicals;
- Whether certain chemicals, or groups of chemicals, would benefit from some preliminary work to assure that risk assessments are targeted and scoped appropriately, and therefore, would best be addressed in an out year;
- Whether certain chemicals, or groups of chemicals, have previously been assessed and addressed by EPA, so that risk assessment in later years may be more appropriate than in the earlier years of the Work Plan; and
- EPA work load considerations, including scope and timing of work needed on specific chemicals, and existing commitments for assessment.
EPA remains committed to identifying and conducting risk assessments of existing chemicals to identify and address any risks the assessments may reveal. EPA is to be congratulated on hitting its spring 2012 mark to identify its 2013/2014 priorities for risk assessment. Making and meeting commitments is an important element in demonstrating that the toxics program can deliver. We look forward to future such demonstrations, particularly on OPPT's commitment to complete risk assessments in 2012 on 'some' of the seven priority chemicals identified in March. Hitting that mark for some significant number of the seven chemicals would be a clear demonstration of OPPT's ability to deliver on its assessment commitments.
As noted in our earlier memorandum on EPA's Work Plan Chemicals initiative, OPPT is interested in both identifying risks that existing chemicals may pose and in ensuring the office institutionally develops the protocols, risk assessment tools, and practices it needs to demonstrate its ability to conduct risk assessments comparable to other EPA program offices with more institutional experience in such matters. EPA is also telegraphing its interest in assessing existing chemicals despite the notoriously limited regulatory authority granted to EPA under TSCA, and EPA's ever shrinking budget to undertake new chemical initiatives. In fact, given the bleak picture for EPA's overall budget, and despite the Office of Chemical Safety and Pollution Prevention's (OCSPP) allocation of increased resources to the toxic chemicals program taken from the pesticides program, it would not be surprising if this announced list of chemicals for review in 2013 and 2014 will completely fill the program's current organizational capacity.