Availability of Final Data Summaries and Priorities for 33 Chemicals With Respect to Their Potential to Cause Cancer

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 (Proposition 65). As the lead agency, OEHHA has developed a procedure for prioritizing chemicals for consideration under Proposition 65 by the "State’s qualified experts". Two committees of the Science Advisory Board (SAB), known as the Carcinogen Identification Committee, and the Developmental and Reproductive Toxicant (DART) Identification Committee, serve as the State’s qualified experts for rendering an opinion as to whether a chemical is known to the State to cause cancer, birth defects or other reproductive harm.

The procedure used by OEHHA to identify, prioritize and select candidate chemicals for evaluation by the SAB Committees is described in, "Procedure for Prioritizing Candidate Chemicals for Consideration Under Proposition 65 by the State’s Qualified Experts". This procedure ensures that chemicals posing the highest level of cancer, birth defects or reproductive hazard concern are addressed first and forthwith by the SAB. The initial batch of chemicals under consideration for their potential to cause cancer were selected before refinements to the prioritization procedure were made. Draft data summaries and draft priorities were released for public comment on May 17, 1996. As a result of the refinements, a second public comment period was announced on October 4, 1996. Each notice initiated a 60-day public comment period for the chemicals indicated below. Several comments and information were received. OEHHA staff evaluated the submittals. The comments and information received did not change the draft priority assignments. The final priority assignments for the chemicals are:

Category IIa

Acetaminophen (paracetamol) 103-90-2 Low
Acetoxime 127-06-0 Medium
Acrolein 107-02-8 Medium
Benzyl acetate 140-11-4 Low
Butyl benzyl phthalate 85-68-7 Low
Carbaryl 63-25-2 Medium high
Chloramben 133-90-4 Low
Chloroacetaldehyde 107-20-0 Medium
(fluorocarbon 31)
593-70-4 Medium
C.I. Disperse Yellow 3 2832-40-8 Medium
Clomiphene and its salts 911-45-5 Medium
Coumarin 91-64-5 Medium
Decabromobiphenyl oxide 1163-19-5 Low
Dichloro-p-phenylenediamine, 2,6- 609-20-1 Medium
Ethyl parathion 56-38-2 Low
Eugenol 97-53-0 Low
Hydralazine and its hydrochloride 86-54-4 and
Medium high
Hydroquinone 123-31-9 Medium high
Isophorone 78-59-1 Low
Mercuric chloride 7487-94-7 Medium
Naphthalene 91-20-3 Low
Nitrofurantoin 67-20-9 Medium
Nitro-o-toluidine, 5- 99-55-8 Medium high
Nitro-p-phenylenediamine, 2- 5307-14-2 Medium
Ozone 10028-15-6 Medium
Pentachloroanisole (pentachloromethoxybenzene) 1825-21-4 Medium
Propyl gallate 121-79-9 Low
Semicarbazide hydrochloride 563-41-7 Medium
Trifluralin 1582-09-8 Medium
Vinyl acetate 108-05-4 Medium high

CASRN = Chemical Abstracts Service Registration Number
aCategory II consists of those chemicals which are assigned a priority level of concern other than "high". No action is anticipated for Category II chemicals until all chemicals identified as posing a high hazard of concern have been identified from the tracking database, assigned to the Candidate List, and brought before the appropriate Committee of the Science Advisory Board.


Candidate List
Chemicals Under Consideration for Possible Listing by the State's Qualified Experts


5-chloro-o-toluidine and its strong
acid salts*
95-79-4 High
Quinoline and its strong acid salts* 91-22-5


2,4,5-trimethylaniline and its strong acid salts* 137-17-7 High

CASRN = Chemical Abstracts Service Registration Number
*To be considered at the September 25, 1997 meeting of the Carcinogen Identification Committee (see the notice published in the California Regulatory Notice Register on July 25, 1997.)

Copies of the final data summaries and priority assignments for these chemicals are available from the Proposition 65 Implementation Office at the address and telephone number indicated below or from the downloads section below.

Proposition 65
Office of Environmental Health Hazard Assessment
Post Office Box 4010
Sacramento, CA 95812-4010
FAX (916) 327-1097
(916) 445-6900