| environ. | lead compound Lead compounds are present as gasoline additives, in paint, ceramic products, roofing, caulking, electrical applications, tubes, or containers. Lead exposure may be due to air, water, food, or soil. Lead in the air is primarily due to lead-based fuels and the combustion of solid waste, coal, oils, and emissions from alkyl lead manufacturers, wind blown dust volcanoes, the burning of lead-painted surfaces, and cigarette smoke. Lead in drinking water comes from leaching from lead pipes, connectors, and solder in both the distribution system and household plumbing | kompost taċ-ċomb |