Paint rags are a hazard, too. If you've been using latex paint, dry the rags thoroughly and wrap in newspaper before disposing in a trash can. Latex paints can be cleaned up with soap and water, but brush out as much paint as possible on newspaper to keep too much paint from going down the drain when you clean brushes. When you do use soap and water, do it in a sink, not over a storm drain. If you need to apply paint in a place where looks aren't terribly important, use up some of that paint left over from last year or borrow some from a neighbor instead of buying new paint.
Recycled paint is another good choice.
Paint Disposal First, try to use up or give away any extra paint. Small amounts of latex or water-based paints can be left to dry in the can and, once solid, thrown in the garbage. Open the can and place in an area away from children and animals. After the paint dries, discard it in the trash with the lid off. Alternatively, use up the last bit of paint by painting scrap wood or cardboard, allow to dry, and then discard in the trash.