... Keeping the heavy metals out of the water supply. Frequently I use paper palettes for that reason, but yesterday I could not find any and had to use my old enamel butcher's tray. To remove acrylic it is a simple matter of turning on the hot water and it lifts, but then what? I worked out this system of cheesecloth in a strainer in the bathroom sink. Then I throw away the cheesecloth, and voila, cadmium, titanium, cobalt and copper phthalocyanine ... away with you!
I use acrylic for very practical reasons. No solvents, no oily rags, no fumes, no pigments left on the skin to be absorbed (yes, they can go right into the bloodstream). The problem of disposal has always been a concern. Now I can use my non-disposable palette without worrying about how to get that skin of paint off without letting it go down the drain.