The Office of Environmental Health Hazard Assessment added a-methyl styrene and sulfur dioxide to the list of chemicals known to cause reproductive toxicity, and set the final Public Health Goal for hexavalent chromium in drinking water at 0.02 parts per billion. The listing and publication took effect July 29, 2011. http://www.oal.ca.gov/res/docs/pdf/notice/30z-2011.pdf pp. 1215-35.