Changed Notice of Proposed Rulemaking Specific Regulatory Levels Posing No Significant Risk: 4-Methylimidazole (4-MEI)

As required by Government Code section 11346.8(c), and Title 1, Section 44 of the California Code of Regulations, the Office of Environmental Health Hazard Assessment (OEHHA) is providing notice of a change made to the proposed regulation establishing a No Significant Risk Level (NSRL) for 4-MEI (Title 27, California Code of Regulations, section 25705), and augmentation of the record with additional scientific references.  This proposed regulatory action is being taken pursuant to OEHHA’s authority under the Safe Drinking Water and Toxic Enforcement Act of 1986, commonly known as Proposition 65, and codified at Health and Safety Code section 25249.5 et seq. This proposed regulation was originally the subject of a Notice of Proposed Rulemaking published on January 7, 2011, in the California Regulatory Notice Register (Register 2011, No 1-Z), which initiated a public comment period. A Notice Extending the Public Comment Period and Announcement of a Public Hearing was published in the California Regulatory Notice Register on February 18, 2011 (Register 2011, #7-Z), p. 228. A public hearing on this regulatory proposal was held on March 10, 2011.  Written comments from the public were received during the comment period which ended March 24, 2011. 

The proposed NSRL for 4-MEI has been changed to 29 micrograms per day. A copy of the text of the amended proposed regulation is attached.  The new modifications are shown in double-underline and double-strike-out. OEHHA is making available (1) a copy of the text of the amended proposed regulation, and (2) a modified technical support document describing the information that OEHHA relied on in its determination on the revised proposed NSRL. These are available on the OEHHA website at, or may be requested from Monet Vela at the OEHHA Legal Office at (916) 323-2517. The public comments received during the prior comment period are available upon request.

OEHHA will accept written comments on these amendments to the proposed regulation between October 7, 2011, and October 24, 2011.  All written comments must be submitted to OEHHA by mail, fax, courier, e-mail, or hand-delivery by no later than 5:00 p.m. on October 24, 2011. Comments should be addressed to:

Fran Kammerer
Office of Environmental Health Hazard Assessment
P. O. Box 4010
1001 I Street
Sacramento, California 95812-4010
Fax No.: 916-324-1786

Inquiries concerning the action described in this notice may be directed to Fran Kammerer at the address given above, or by telephone at (916) 445-4693. Monet Vela is a back-up contact person and is available at (916) 323-2517.

OEHHA is augmenting the record to include the following references used in the development of the proposed NSRL for 4-MEI.

Footnotes and References

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