The Environmental Protection Agency (EPA) has updated its Toxic Substances Control Act (TSCA) Work Plan of chemicals for further assessment.[1]  EPA first released the TSCA Work Plan in early 2012 to help focus and direct the activities of its Existing Chemicals Program.[2]  The changes to the TSCA Work Plan for Chemical Assessments reflect updated industry data submitted to EPA through the Toxics Release Inventory (TRI) in 2011 and the TSCA Chemical Data Reporting (CDR) requirements in 2012, particularly data indicating the presence of many of these chemicals in consumer products.  In its announcement of the update, EPA stated that the 23 chemicals added to the TSCA Work Plan will not be considered for assessment until after 2017.

The Agency continues to use the process described in the TSCA Work Plan Chemicals Methods Document, which focuses on chemicals that meet one or more of the following factors:

  • Potential concern for children’s health (e.g., reproductive or developmental effects)
  • Neurotoxic effects
  • Persistent, bioaccumulative and toxic
  • Probable or known carcinogens
  • Used in children’s products or products to which children may be highly exposed
  • Detected in biomonitoring programs

On the basis of updated industry data submitted to EPA through TRI and CDR, EPA re-screened the 345 candidate chemicals identified in 2012 and updated exposure rankings.  The chemicals added include:

  • 4,4'-(1-methylethylidene)bis[2,6-dibromophenol] (TBBPA, a brominated flame retardant),
  • molybdenum and molybdenum compounds,
  • 1,3-butadiene,
  • 2,5-furandione,
  • 2-dimethylaminoethanol,
  • 2-hydroxy-4-(octyloxy)benzophenone,
  • 3,3’-dichloro-benzidine,
  • barium carbonate,
  • dicyclohexyl phthalate,
  • isopropylated phenol phosphate (iPTPP),
  • pentachlorothiophenol, and
  • triphenyl phosphate (TPP).

In addition, chemicals and chemical groups from EPA’s “Action Plans,” the Agency’s prior (2009-2011) process for chemical assessment and regulation, were also added to the Work Plan:

  • bisphenol A (BPA),
  • decabromodiphenyl ether (decaBDE),
  • hexabromocyclododecane (HBCD) (assessment has started),
  • nonylphenols and nonylphenol ethoxylates (NPs/NPEs), and
  • a group of phthalates (dibutyl phthalate (DBP), butyl benzyl phthalate (BBP), di(2-ethylhexyl) phthalate (DEHP), di-n-octyl phthalate (DnOP), di-isononyl phthalate (DINP), di-isodecyl phthalate (DIDP), and di-isobutyl phthalate (DIBP)).

While overall the TSCA Work Plan has grown from 83 to 90 chemicals, a number of chemicals were removed from it by EPA’s update.  These include mercury and mercury compounds, which were deemed already well-characterized; quartz, for which potential exposures are regulated by the Occupational Safety and Health Administration; and benzo[a]pyrene, which will be evaluated as part of EPA's assessment for creosote.  EPA also removed other chemicals: 1,2,4,5-tetrachloro-benzene, 4-chloro-2-methylaniline (p-chloro-o-toluidine), benz(a)anthracene, dibenz(a,h)anthracene, dibromochloromethane, dichloroacetic acid, hexabromobiphenyl, hexachlorocyclohexane, N-nitroso-ethylamine, N-nitrosodimethylamine, pentabromophenol, polychlorinated naphthalenes, and Tris(2,3-di bromopropyl) phosphate (TBP).

EPA completed assessments for four chemicals that are on the TSCA Work Plan earlier in 2014: trichloroethylene (TCE), methylene chloride or dichloromethane (DCM), 1,3,4,6,7,8-hexahydro-4,6,6,7,8,8,-hexamethylcyclopenta[γ]-2-benzopyran (HHCB), and antimony trioxide (ATO).  To date, EPA has initiated assessments for clusters of chlorinated phosphate esters flame retardants and brominated phthalate flame retardants, and seven other chemicals and groups.

EPA’s efforts under its TSCA Work Plan will operate, at least in the near future, under the shadow of continuing efforts in Congress to enact a modernized chemicals management framework to modify or overhaul TSCA and its mechanisms for review of existing chemicals.  It is uncertain how these two tracks will interact.