Issuance of a Safe Use Determination for Diisononyl Phthalate in Certain Single-Ply Polyvinyl Chloride Roofing Membrane Products

Note: Correction to Analysis Supporting a Safe Use Determination for Diisononyl Phthalate in Certain Single-Ply Polyvinyl Chloride Roofing Membrane Products Issued on June 24, 2016.

The California Environmental Protection Agency’s Office of Environmental Health Hazard Assessment (OEHHA) is the lead agency for the implementation of the Safe Drinking Water and Toxic Enforcement Act of 19861. OEHHA received a request from the Chemical Fabrics & Film Association, Inc. (CFFA) that OEHHA issue a Safe Use Determination (SUD) for the use of diisononyl phthalate (DINP) in certain single-ply (SP) polyvinyl chloride (PVC) roofing membrane products, pursuant to OEHHA’s authority under Section 25204(a) of Title 27 of the California Code of Regulations.2 The products that are the subject of the request are SP PVC roofing membrane products with a nominal thickness of between 1.016 to 2.438 millimeters (40 to 96 mils), containing no more than 15 percent DINP and heated to surface temperatures up to and including 210ºC during installation. The roofing membrane products that are the subject of this request are installed by roofing professionals. DINP was listed under Proposition 65 as a chemical known to the state to cause cancer effective December 20, 2013.

In accordance with the process set forth in Section 25204(f), OEHHA held a written public-comment period on this request from April 17 to May 19, 2015, particularly with respect to the potential for exposure to DINP that may result from the installation of these SP PVC roofing membrane products by roofing professionals. OEHHA also held a public hearing on May 19, 2015, in Sacramento, California. No public comments were received.

As provided in Sections 25204(a) and (k), OEHHA is issuing this SUD only to CFFA for DINP in SP PVC roofing membrane products with a nominal finished thickness of between 1.016 to 2.438 mm, containing no more than 15 percent DINP and heated to surface temperatures up to and including 210ºC during installation. The essential elements and results of OEHHA’s assessment are described in the supporting document available below.

Based on the screening level exposure analysis described in the supporting documentation, an upper-end estimate of DINP exposures to professional roof installers during the installation of the specified SP PVC roofing membrane products is 83 micrograms (µg) per day. This estimate of exposure is approximately 57 percent of the proposed No Significant Risk Level (NSRL) for DINP of 146 µg/day3, and corresponds to an excess cancer risk of less than one in 100,000.

Questions regarding this notice should be directed to:

Michelle Robinson
Office of Environmental Health Hazard Assessment
P.O. Box 4010, MS-12B
Sacramento, California 95812-4010

P65Public.Comments@oehha.ca.gov
Telephone: (916) 445-6900

Footnotes and References

1 The Safe Drinking Water and Toxics Enforcement Act of 1986, commonly known as Proposition 65, is codified at Health and Safety Code section 25249.5 et seq.

2All further references are to sections of Title 27 of the California Code of Regulations unless otherwise stated.

3Proposed Amendment to: Section 25705(b) Specific Regulatory Levels Posing No Significant Risk. Diisononyl Phthalate (DINP) January 2, 2015.