From the OEHHA:

The Office of Environmental Health Hazard Assessment (OEHHA) of the California Environmental Protection Agency is adding gallium arsenide to the list of chemicals known to the state to cause cancer and hexafluoroacetone, nitrous oxide and vinyl cyclohexene dioxide to the list of chemicals known to the state to cause reproductive toxicity for the purposes of Proposition 65. The listing of gallium arsenide, hexafluoroacetone, nitrous oxide and vinyl cyclohexene dioxide is effective August 1, 2008…

Cancer:

Gallium arsenide – CAS No. 1303-00-0

Reproductive Toxicity:

Hexafluoroacetone – CAS No. 684-16-2 – Male reproductive toxicity

Nitrous oxide – CAS No. 10024-97-2 – Developmental toxicity

Vinyl cyclohexene dioxide – CAS No. 106-87-6 – Female and male reproductive toxicity

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