Neither the ceramic or organic coatings use heavy metals, so they are compliant with California’s Proposition 65, known officially as the Safe Drinking Water and Toxic Enforcement Act of 1986. The act requires a warning label on any product sold in California that contains chemicals, such as heavy metals used in many packaging inks, known to the state to cause cancer and birth defects or other reproductive harm. Yet the Mask Spray coatings still provide vibrant color without the use of heavy metals. Complying with Prop 65 is a pretty big deal, especially since California is home to so many wineries.