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Assessing and Managing Chemicals under TSCA

Risk Evaluation for Phosphoric Acid, Triphenyl Ester (TPP)

EPA designated triphenyl ester (TPP) as a High-Priority Substance in December 2019 and the chemical is currently undergoing risk evaluation.

Find other information about other chemicals undergoing risk evaluations under TSCA

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Background on TPP

TPP (CASRN 115-86-6) is a colorless solid. The primary uses for TPP are as a flame retardant or solvent in chemical and plastics manufacturing. Information from the 2016 Chemical Data Reporting (CDR) for TPP indicates the reported production volume is between 1 million and 10 million lbs/year (manufacture and import).

Conditions of Use of TPP

In the final scope, EPA identified conditions of use associated with the importing; processing; distribution in commerce; industrial, commercial and consumer uses; and disposal of TPP, for example:

  • The flame retardant is processed as a reactant, incorporated into a formulation, mixture, or reaction products, and incorporated into articles;
  • TPP is reportedly used in commercial paints and coatings and for plastic and rubber products; and
  • Several consumer uses were reported, including foam seating and bedding products.

The above listed conditions of use are ways that a person or the environment could be potentially exposed to this chemical. However, when conducting a risk evaluation, EPA also considers the hazards (i.e. health effects or environmental impacts) that could occur from coming in contact with a chemical.

Recent Activities and Opportunities for Public Comment

In August 2020, EPA published a final scope document outlining the hazards, exposures, conditions of use, and the potentially exposed or susceptible subpopulations the agency expects to consider in its risk evaluation. The agency released the draft scope in April 2020 and took public comments on the draft document.

As EPA continues to move through the risk evaluation process there will be additional opportunities for public comment, including a public comment period on the draft risk evaluation. In addition to public comment periods, EPA will continue to engage with stakeholders as it refines the risk evaluation and stakeholders should reach out to EPA via the staff contact to engage with the agency.