By Patrick Ambrosio
The Environmental Protection Agency announced plans March 27 to begin full risk assessments on seven chemicals in 2013, including four flame retardants.
The agency's 2013 Toxic Substances Control Act work plan identified plans to study 20 flame retardant chemicals, using information from the four full risk assessments to better understand other similar chemicals that lack sufficient data for a full risk assessment. The agency also plans to investigate some flame retardants to determine how they transform and move in the environment.
The four flame retardants that will undergo a full risk assessment are:
• 2-ethylhexyl ester 2,3,4,5-tetrabromobenzoate (TBB);
• 1,2- ethylhexyl 3,4,5,6-tetrabromo-benzenedicarboxylate, or (2-ethylhexyl)-3,4,5,6 tetrabromophthalate (TBPH);
• tris(2-chloroethyl) phosphate (TCEP); and
• hexabromocyclododecane (HBCD).
EPA plans to assess eight additional flame retardants by grouping chemicals with similar characteristics together with the four flame retardants targeted for full risk assessment.
The other three chemicals slated for full risk assessments are 1-bromopropane, 1,4-dioxane, and octamethylcyclotetrasiloxane (D4).
Jim Jones, acting assistant administrator for chemical safety and pollution prevention, said in a March 27 statement that EPA is “committed to more fully understanding the potential risks of flame retardant chemicals, taking action if warranted, and identifying safer substitutes when possible.”
A coalition of 23 senators recently sent a letter to EPA requesting that the agency fully assess risks associated with flame retardant chemicals (37 CRR 220, 2/25/13).
EPA said a review of available data on flame retardant chemicals identified approximately 50 chemicals that are unlikely to pose a risk to human health and could be used as alternatives to more toxic chemicals.
EPA's 2013 work plan also includes a full risk assessment for the widely used industrial chemical 1-bromopropane. The chemical is used as a solvent in some commercial applications, including dry cleaning, and to degrease electronics, precision optics, and metals.
A peer-review panel convened by the National Toxicology Program recently recommended that 1-bromopropane be classified as a “reasonably anticipated human carcinogen” and included in the Report on Carcinogens, which would trigger hazard communication requirements and could lead to additional regulation in some states 37 CRR 337, 3/25/13).
According to EPA's work plan, 1,4-dioxane, a solvent found in some household cleaning products, also is scheduled to undergo a full risk assessment in 2013.
Procter & Gamble Co., the manufacturer of Tide® and other laundry detergents, recently agreed to reduce the level of 1,4-dioxane in its laundry detergents to less than 25 parts per million after an environmental group alleged that sale of the detergents was in violation of a California state law requiring products containing chemicals listed as known carcinogens to feature a warning label (As You Sow v. Procter & Gamble Co., Cal. Super. Ct. San Francisco, CGC-12-517674, 1/22/13; 37 CRR 175, 2/11/13).
EPA also will conduct a full risk assessment on octamethylcyclotetrasiloxane (D4), a high production volume chemical with a wide variety of industrial, commercial, and consumer uses.
The agency encourages the submission of additional relevant information on the chemicals selected for risk assessment. Additional information should be submitted by May 30 at http://www.regulations.gov under Docket ID No. EPA-HQ-OPPT-2011-0516.
EPA also announced plans to launch environmental fate investigations of eight flame retardants for which there is not adequate data available to conduct a full risk assessment.
The investigations will focus on the mechanisms for the breakdown of larger molecules into degradants and how the persistence and bioaccumulation potentials of a parent compound compares to those of its degradants.
The eight chemicals, all of which are believed to rank high for persistence, bioaccumulation, or exposure potential compared to other chemicals, are:
• 1,2,4,5-tetrabromo-3,6-bis(pentabromophenoxy)-benzene or tetradecabromo-1,4-diphenoxybenzene;
• 1,2 bis(penetabromophenyl) ethane (DBDPE);
• 1,1'-[1,2-ethanediylbis(oxy)]bis[2,3,4,5,6-pentabromo-benzene] or 1,2-bis(2,3,4,5,6-pentabromophenoxy) ethane;
• 1,1'-[1,2-ethanediylbis(oxy)]bis[2,4,6-tribromobenzene] or 1,2-bis (2,4,6-tribromophenoxy) ethane (TBE);
• benzene,1,3,5-tribromo-2-(2,3-dibromopropoxy) (DPTE); and
• two chemicals whose identities have been claimed as confidential.
Additional information on EPA's chemical risk assessment activities for 2013 is available at http://www.epa.gov/oppt/existingchemicals/pubs/2013wpractivities.html#risk.