Request for Relevant Information on the Carcinogenic hazards of Diaminotoluenes

The California Environmental Protection Agency’s Office of Environmental Health Hazard Assessment (OEHHA) has added diaminotoluene (mixed) to the Proposition 65 list of chemicals known to the state to cause cancer on 1 January 1990. It was formally identified by the US Environmental Protection Agency (US EPA) as causing cancer. OEHHA received a petition from Big Lots Stores, Inc. (petition can be found here) for reconsideration of listing for diaminotoluene (mixed) on 21 October 2014. While the US EPA (1988) basis document indicates that the hazard ranking of diaminotoluene (mixed) “is applicable to all isomers of diaminotoluene”, and that the “evidence on potential carcinogenicity from animal studies is “sufficient””, the US EPA document also indicates that “this evidence is based on the carcinogenic properties of the isomer 2,4-diaminotoluene”. No other information on the mixture or individual isomers is included in the US EPA document. In order to clarify the scope of the listing, OEHHA is referring diaminotoluene (mixed) to the CIC for a determination as to whether the chemical should continue to be included on the list of chemicals known to the state to cause cancer pursuant to Title 27, Cal. Code of Regs., section 25306 (j). At a future meeting, the committee will consider the available scientific evidence on the chemical group diaminotoluene (mixed) as well as on the individual isomers in that group, and make a determination on whether diaminotoluenes as a group, the mixtures or any of five individual isomers named in the table below should be listed under Proposition 65. 2,4-Diaminotoluene will not be re-considered, as it was individually added to the list by the Science Advisory Panel (the predecessor entity to the CIC) on 1 January 1988.


Chemicals for Preparation of Cancer Hazard Identification Materials


Chemicals CAS No.         
Diaminotoluene (mixed)
2,3-Diaminotoluene 2687-25-4
2,5-Diaminotoluene 95-70-5
2,6-Diaminotoluene 823-40-5
3,4-Diaminotoluene 496-72-0
3,5-Diaminotoluene 108-71-4

By this notice, OEHHA is giving the public an opportunity to provide information relevant to the assessment of the evidence of carcinogenicity for diaminotoluene (mixed), diaminotoluenes, 2,3 diaminotoluene, 2,5-diaminotoluene, 2,6-diaminotoluene, 3,4-diaminotoluene, and 3,5-diaminotoluene. Relevant information includes but is not limited to:

  1. Cancer bioassays
  2. Cancer epidemiology studies
  3. Genotoxicity testing
  4. Other pertinent data on: Pharmacokinetics, biomarkers
  5. Effects on biochemical and physiological processes in humans

Interested parties wishing to make a submission must do so by 22 December 2014. The information received during this period will be reviewed and considered by OEHHA as it prepares the cancer hazard identification materials on these chemicals. Hazard identification materials are made available to the public for comment prior to the CIC’s consideration of the chemical for possible listing. Their availability for comment will be announced in the California Regulatory Notice Register and on OEHHA’s website. Public comments received on these materials are sent to the CIC for its consideration prior to the CIC meeting at which the chemicals will be considered for listing. The time, date, location, and agenda of the CIC meeting will also be published in the California Regulatory Notice Register and posted on OEHHA’s website.

OEHHA, 23 October 2014 ; ;