The federal government banned the sale of lead paint in 1978 because it can cause kidney and reproductive problems in adults and, worse, physical and mental developmental issues in children. After more than three decades, it's likely that the half-used can you found in the garage has dried out. But if you unearth an untouched gallon sitting on a back shelf, resist the urge to use it, even for a small project. More important, find out how to dispose of it properly in your municipality; don't just throw it away. And if you realize the same shade of blue on the can is the one in that now-peeling kids' bedroom, buy a lead-testing kit and look up the number of a certified abatement specialist. Contractors doing painting or remodeling are now required by federal law to get training in preventing lead contamination and must follow strict demolition and disposal guidelines, so getting rid of the stuff in places where the dust can get to children is a job best left to the pros.