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Assessing and Managing Chemicals under TSCA

Risk Evaluation for Di-isodecyl phthalate (DIDP) (1,2-Benzene- dicarboxylic acid, 1,2- diisodecyl ester)

EPA granted the manufacturer request for risk evaluation for di-isodecyl phthalate (DIDP) (1,2-Benzene- dicarboxylic acid, 1,2- diisodecyl ester) in December 2019, and this category of chemicals is currently undergoing risk evaluation.

Learn more about manufacturer-requested risk evaluations.

Find other information about other chemicals undergoing risk evaluations under TSCA

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Background on DIDP

DIDP is a common chemical name for the category of chemicals that includes the following substances: 1,2-benzenedicarboxylic acid, 1,2-diisodecyl ester and 1,2-benzenedicarboxylic acid, di-C9-11-branched alkyl esters, C10-rich. The primary use for DIDP is as a plasticizer in plastic and rubber products.  Information from the 2016 Chemical Data Reporting (CDR) for DIDP indicates the reported production volume is between 100 million and 270 million lbs/year (domestic manufacture including import).

Uses of DIDP

In the draft scope of the DIDP risk evaluation, EPA preliminarily identified conditions of use associated with the importing; processing; distribution in commerce; industrial, commercial and consumer uses; and disposal of DIDP, including:

  • As a plasticizer in polyvinyl chloride (PVC);
  • In building and construction materials;
  • In automotive care and fuel products; and
  • In other commercial and consumer products, including adhesives and sealants, paints and coatings, electrical and electronic products, and other plastic and rubber 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 November 2020, EPA released the draft scope of the DINP risk evaluation for public comment. EPA will accept comments in docket EPA-HQ-OPPT-2018-0435 for 45 days.

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 develops the risk evaluation. Stakeholders should reach out to EPA via the staff contact to engage with the agency.