Every effort is made to source products in a responsible manner, which comply with local regulations. On such regulation in California, is the Safe Drinking Water and Toxic Enforcement Act of 1986; this is more commonly known as Proposition 65. This regulation requires the provision of a warning to California consumers, regarding products containing certain chemicals:

WARNING: This product contains chemicals known to the State of California to cause cancer and birth defects or other reproductive harm

For more information about Proposition 65, please visit the California OEHHA Proposition 65 program at http://www.oehha.ca.gov/prop65.html or http://oehha.ca.gov/proposition-65/proposition-65-list.