Proposition 65 is a California law that has been in effect since 1986 to promote clean drinking water and keep toxic substances that cause cancer and birth defects out of consumer products. Proposition 65's formal title is "The Safe Drinking Water and Toxic Enforcement Act of 1986." It is administered by Cal/EPA's Office of Environmental Health Hazard Assessment (OEHHA). The law requires that anyone at reasonable risk of exposure be informed when substances classified as toxins are present. Since enactment, it has been the reason for the addition of notices of specific contents to consumer product labels. Along with the added label requirements, an official list of implicated substances is maintained and made publicly available. Entries are added or removed based on current scientific information. All substances listed show their known or suspected risk factors, a unique CAS chemical classification number, the date they were listed, and if so, whether they have been delisted.