Correction to Analysis Supporting a Safe Use Determination for Diisononyl Phthalate in Certain Single-Ply Polyvinyl Chloride Roofing Membrane Products Issued on December 4, 2015

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 1986[1]

On December 4, 2015, OEHHA Issued a Safe Use Determination (SUD) to the Chemical Fabrics & Film Association, Inc. (CFFA) for 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 SUD 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.

This notice announces that some of the information used in OEHHA’s analysis supporting the issuance of this SUD has been corrected.  Specifically, the content of DINP in the secondary backing layer of carpet tiles used to generate data on hand and fingertip loading of DINP has been corrected from 21.1 percent to 9 percent.  This information is used in OEHHA”s analysis for this SUD to estimate DINP exposures via the dermal absorption and incidental ingestion pathways.  Use of the corrected information results in an increase in the upper-end estimate of DINP exposures to professional roof installers during the installation of the specified SP PVC roofing membrane products from 83 to 109 micrograms (µg) per day.  This corrected estimate of exposure is approximately 75 percent of the No Significant Risk Level for DINP of 146 µg/day, and corresponds to an excess cancer risk of less than one in 100,000.

The essential elements and results of OEHHA’s corrected assessment are described in the supporting document available at:  /proposition-65/proposition-65-safe-use-determinations-suds.  This 2016 supporting document supersedes the previous document of November 2015.

Questions regarding this notice should be directed to:

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

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.

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