By Carolyn Whetzel
Dec. 13 --A California
scientific advisory panel has cleared the way for the state's Office of
Environmental Health Hazard Assessment to add a common plasticizer, diisononyl
phthalate, to the list of carcinogens the agency maintains under Proposition
65, the Safe Drinking Water and Toxic Enforcement Act of 1986.
listing will be effective Dec. 20, OEHHA said in a Dec. 12 regulatory
OEHHA's Carcinogen Identification Committee considered the
scientific evidence for listing diisononyl phthalate and butyl benzyl
phthalate, another additive used to make materials softer and more pliable, as
carcinogens under Proposition 65, at its Dec. 5 meeting in Sacramento.
The committee determined the scientific data “clearly’’ showed diisononyl
phthalate could cause cancer, according to the notice. As to butyl benzyl
phthalate, the committee voted against adding it to the list of carcinogens,
OEHHA spokesman Sam Delson told Bloomberg BNA in a Dec. 12 e-mail.
Proposition 65 requires California to maintain a list of chemicals known to
cause cancer, birth defects or reproductive toxicity. Businesses must provide
clear warnings whenever exposing the public to an unsafe level of a listed
OEHHA's next step will be to establish a safe exposure level
for diisononyl phthalate.
Both phthalates are high production volume
chemicals, meaning they are made in or imported into the U.S. in volumes of 1
million pounds or more annually, according to the U.S. Environmental Protection
Butyl benzyl phthalate (BBP) is used in polyvinyl chloride
products, including flooring tiles and carpet backing, and as additive in food
packaging materials, medical devices, leather coatings, paint, adhesives and
Since 2009, federal and California laws have restricted the sale
and distribution of toys and child care articles containing BBP concentrations
of more than 0.1 percent (1,000 parts per million).
(DINP) is a general purpose plasticizer used in a variety of products including
vinyl flooring, wire and cable insulation, stationery, coated fabrics, gloves,
toys, tubing, garden hoses, footwear, automobile undercoatings and roofing
materials. The phthalate ester also is found in rubbers, inks, paints, lacquers
California law bars the sale and distribution of toys and
child care products with DINP concentrations that exceed 0.1 percent.
OEHHA's advisory committee listed DINP based on animal studies showing oral
exposure increased the incidence of liver tumors, islet cell tumors of the
pancreas and mononuclear cell leukemia (spleen) in male and female rats; kidney
tumors in male rats; testicular cell cancer in male rats; and uterine tumors in
Exxon Mobil Chemical (a division of Exxon Mobil Corp.),
BASF Corp. and several industry groups submitted written comments in November
opposing the listing of DINP as a carcinogen.
“Diisononyl phthalate does
not meet the standard for listing under Proposition 65 as a carcinogen,” Exxon
Mobil Chemical said in its comments. “The weight-of-evidence is that, while
high doses of DINP cause tumors in rodents, the specific tumor types are widely
known to be not relevant to human cancer assessment.”
identification document for DINP didn't provide a balanced and complete summary
of the scientific evidence, Exxon Mobil Chemical said.
Chemistry Council, California Manufacturers & Technology Association
(CMTA), the California Building Industry Association and McKenna Long &
Aldridge's San Francisco-based attorney Stanley Landfair, on behalf of BASF
Corp., all submitted similar, detailed comments opposing the listing.
his comment letter, Michael J. Rogge of CMTA said “there is a wide body of
science that supports the safety of DINP and that it does not cause
carcinogenic effects in humans.
“DINP has been safely used in products
for decades with no known carcinogenic effects to humans,” Rogge, the group's
policy director for environmental quality, said.
Tim Zacharewski, a
professor at Michigan State University's Department of Biochemistry &
Molecular Biology, also submitted comments
saying OEHHA provided “insufficient evidence’’ to warrant the listing of DINP
under Proposition 65.
To contact the reporter on this
story: Carolyn Whetzel in Los Angeles at firstname.lastname@example.org
To contact the editor responsible
for this story: Larry Pearl at email@example.com
notices are available at http://www.oehha.ca.gov/prop65/CRNR_notices/list_changes/122013P65list.html.
The agency's hazard identification document for diisononyl phthalate is
available at http://www.oehha.ca.gov/prop65/hazard_ident/pdf_zip/DINP_HID100413.pdf
The agency's scientific evidence on the carcinogenicity of butyl benzyl
phthalate is available at http://www.oehha.ca.gov/prop65/hazard_ident/pdf_zip/BBP_HID10042013.pdf.
To view additional stories from Chemical Regulation Reporter
® register for a free trial now