Lead has been banned in gasoline and household paint, but it's still present, especially in older homes. It can cause delayed development, learning problems, hyperactivity and other difficulties in children who ingest small but regular amounts. The Environmental Protection Agency estimates 57 million homes in the United States still contain some lead paint. Before 1950, paint contained as much as 50 percent lead. Paint in good condition poses little risk, but paint that is peeling or is deteriorating on surfaces, is risky.
Dust created from the remodeling of an older home also can be a source of lead contamination.
These appliances must be properly vented. Carbon monoxide, a component of combustion, can kill. In small amounts, it can cause flu and allergy symptoms. Excessive amounts of formaldehyde, used as a preservative and adhesive in building products and furnishings, can trigger asthma attacks and damage internal organs, as well as the central nervous system. Take special care when sanding, removing of old paint or exposing existing walls, activities that can release formaldehyde, asbestos, carpet fumes and leaded paint dust.