Intent to List CMNP (Pyrazachlor) and Sedaxane

The California Environmental Protection Agency’s Office of Environmental Health Hazard Assessment (OEHHA) intends to list the chemicals CMNP (pyrazachlor) and sedaxane as known to the State to cause cancer under the Safe Drinking Water and Toxic Enforcement Act of 1986.¹ This action is being proposed under the authoritative bodies listing mechanism.²

Background on listing via the authoritative bodies mechanism: A chemical must be listed under the Proposition 65 regulations when two conditions are met:

1. An authoritative body formally identifies the chemical as causing cancer (Section 25306(d)³).
2. The evidence considered by the authoritative body meets the sufficiency criteria contained in the regulations (Section 25306(e)).

However, the chemical is not listed if scientifically valid data which were not considered by the authoritative body clearly establish that the sufficiency of evidence criteria were not met (Section 25306(f)).

The U.S. Environmental Protection Agency (US EPA) is one of several institutions designated as authoritative for the identification of chemicals as causing cancer (Section 25306(m)).

OEHHA is the lead agency for Proposition 65 implementation. After an authoritative body has made a determination about a chemical, OEHHA evaluates whether listing under Proposition 65 is required using the criteria contained in the regulations.

OEHHA’s determination: CMNP (pyrazachlor) and sedaxane each meet the criteria for listing as known to the state to cause cancer under Proposition 65, based on findings of the US EPA (2011a; b).

Formal identification and sufficiency of evidence for CMNP (pyrazachlor): In 2011, US EPA published a report on CMNP (pyrazachlor) entitled Cancer Assessment Document, Evaluation of the Carcinogenic Potential of CMNP (pyrazachlor) (US EPA, 2011a). This report satisfies the formal identification and sufficiency of evidence criteria in the Proposition 65 regulations for CMNP.

US EPA concluded that CMNP is “Likely to be Carcinogenic to Humans”. OEHHA is relying on US EPA’s discussion of data and conclusions in the report that CMNP (pyrazachlor) causes cancer. Evidence described in the report includes studies showing that CMNP increased the incidence of combined bronchiolar/alveolar carcinomas and adenomas in male mice, bronchiolar/alveolar carcinomas and combined carcinomas and adenomas in female mice, and renal tubule carcinomas and combined carcinomas and adenomas in male and female mice.

Thus, US EPA (2011a) has found that CMNP (pyrazachlor) causes increased incidence of combined malignant and benign lung tumors in male mice, malignant and combined malignant and benign lung tumors in female mice, and malignant and combined malignant and benign kidney tumors in both sexes of mice.

Formal identification and sufficiency of evidence for sedaxane: In 2011, US EPA published a report on sedaxane, entitled Cancer Assessment Document, Evaluation of the Carcinogenic Potential of Sedaxane (US EPA, 2011b). This report satisfies the formal identification and sufficiency of evidence criteria in the Proposition 65 regulations for sedaxane.

US EPA concluded that sedaxane is “Likely to be Carcinogenic to Humans”. OEHHA is relying on US EPA’s discussion of data and conclusions in the report that sedaxane causes cancer. Evidence described in the report includes studies showing that sedaxane increased the incidence of uterine adenocarcinomas and combined adenocarcinomas and adenomas in female rats, and combined hepatocellular carcinomas and adenomas in male mice.

Thus, the US EPA (2011b) has found that sedaxane causes increased incidences of malignant and combined malignant and benign uterine tumors in female rats, and combined malignant and benign liver tumors in male mice.

Request for comments: OEHHA is requesting comments as to whether CMNP (pyrazachlor) and sedaxane meet the criteria set forth in the Proposition 65 regulations for authoritative bodies listings. In order to be considered, OEHHA must receive comments by 5:00 p.m. on Monday, July 27, 2015. We encourage you to submit comments in electronic form, rather than in paper form. Comments transmitted by e-mail should be addressed to P65Public.Comments@oehha.ca.gov with “NOIL – CMNP (pyrazachlor) and sedaxane” in the subject line. Comments submitted in paper form may be mailed, faxed, or delivered in person to the addresses below:

Mailing Address: Ms. Esther Barajas-Ochoa
Office of Environmental Health Hazard Assessment
P.O. Box 4010, MS-12B
Sacramento, California 95812-4010
Fax: (916) 323-2265
Street Address: 1001 I Street
Sacramento, California 95814

Comments received during the public comment period will be posted on the OEHHA web site after the close of the comment period.

If you have any questions, please contact Esther Barajas-Ochoa at esther.barajas-ochoa@oehha.ca.gov or at (916) 445‑6900.

Comment Period

• Comment Period on the Notice of Intent to List CMNP (Pyrazachlor) and Sedaxane

Link to Public Comments

Chemical Reference

• CMNP (Pyrazachlor)
• Sedaxane

Related Notices

• CMNP (Pyrazachlor) Listed Effective August 25, 2015 as Known to the State of California to Cause Cancer

  Aug 21, 2015
• Sedaxane Listed Effective July 1, 2016, as Known to the State of California to Cause Cancer

  Jul 1, 2016

Footnotes and References

References
US Environmental Protection Agency (US EPA, 2011a). Cancer Assessment Document, Evaluation of the Carcinogenic Potential of CMNP (pyrazachlor). Final Report. Health Effects Division, Office of Pesticide Programs. September 20, 2011.

US Environmental Protection Agency (US EPA, 2011b). Cancer Assessment Document, Evaluation of the Carcinogenic Potential of Sedaxane. Final Report. Health Effects Division, Office of Pesticide Programs. May 18, 2011.

¹Commonly known as Proposition 65, the Safe Drinking Water and Toxic Enforcement Act of 1986 is codified in Health and Safety Code section 25249.5 et seq.

² See Health and Safety Code section 25249.8(b) and Title 27, Cal. Code of Regs., section 25306.

³All referenced sections are from Title 27 of the Cal. Code of Regulations.