The California Office of Environment Health Hazard Assessment announced they have added two chemicals known to cause cancer to the Prop 65 list. Alpha-methylstyrene (CAS No. 98-83-9) and 1,3-dinitropyrene (CAS No. 75321-20-9) have been added to the list effective November 2, 2012. The listing was carried out via a mechanism in the Labor Code based up on IARC 2B listing.

Alpha-methylstyrene is used in the manufacturing of plasticizers, resins and polymerization production process. For example, it can be used as an injection mold in the making of floor tiles, sports equipment (snow skis), plastics, floor polishers, tub/shower units, as a resin for stringed musical instruments (violins) and in automobiles allowing the vinyl to be more flexible and more resistant to heat.

1,3-dinitropyrene is a nitrated pyrene that has been found in some carbon blacks and particulate emissions from diesel engines, kerosene heaters and gas burners.