On 30 August 2016, the California’s Office of Environmental Health Hazard Assessment (OEHHA) has adopted significant amendments1 on how clear and reasonable warning is provided under the Safe Drinking Water Enforcement Act of 1986, commonly known as “Proposition 65”. Proposition 65 requires business with 10 or more employees to provide clear and reasonable warning statements in the California State to any listed chemical(s) known as carcinogenic and reproductive toxic. Providing a 2-year transition period, the new warning regulations2 require business to provide more detail to consumers and will effective on 30 August 2018.