Environmentally friendly ways to get rid of excess paint include using a paint take-back program, storing small amounts of paint for touch-up, turning in oil-based paint to hazardous waste sites and using excess paint as a base coat for new finishes. Dried latex paints can be discarded in the garbage.
Legislation in some states requires retailers to take back excess paint. If such programs are in place, they offer an environmentally friendly way to eliminate excess paint. Consumers can reduce waste by using the manufacturer's coverage estimates to determine the correct amount of paint to dry.
Saving some paint at the end of a painting job prevents having to buy more for touch-ups. Paint is less likely to dry out before using it if the consumer stretches plastic wrap over the top, replaces the lid and stores the paint upside down in a cool location.
Excess oil-based paints are hazardous waste. Avoiding their purchase whenever possible is the most environmentally friendly decision. Any excess oil-based paint requires disposal at a hazardous waste collection site.
Mixed leftover paints provide a good base coat for many projects. Latex and oil-based paints do not mix. The resulting mix provides an even color to provide a uniform finished coat.
If latex paints cannot be used, the owner can discard them by pouring the paint into a box filled with cat litter and drying them. He then tosses the litter into the trash.