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Assessing and Managing Chemicals under TSCA

Risk Evaluation for Phthalic Anhydride

EPA designated phthalic anhydride as a High-Priority Substance in December 2019 and the chemical is currently undergoing risk evaluation.

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Background on Phthalic Anhydride

Phthalic anhydride (CASRN 85-44-9) is a white solid. The primary use for phthalic anhydride is as a reactant used for processing. Information from the 2016 Chemical Data Reporting (CDR) for phthalic anhydride indicates reported production volume is between 500 million and 750 million pounds (manufacture and import).

Conditions of Use of Phthalic Anhydride

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 phthalic anhydride, for example:

  • Plastic material and resin manufacturing;
  • Paint and coating manufacturing;
  • Petroleum lubricating oil and grease manufacturing;
  • Synthetic dye, pigment and printing ink manufacturing;
  • Other basic organic and inorganic chemical manufacturing;
  • Adhesives and sealant chemicals;
  • Laboratory chemicals;
  • In industrial and commercial products, including automobile interiors, aerospace products, electronic products, lubricants, plastic and rubber products, processing aids in hydraulic fracturing, water filtration applications, oil treatment of wood, and wire coating and insulation; and 
  • In commercial and consumer products, including paints and coatings and adhesives.

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.