TagEnvironment(69)

aware of the health risks of eating vegetables grown where there are high levels of heavy metals. (They are called heavy metals because their atoms are heavy.) Lead, cadmium and arsenic can be present in our environment from many difference sources. High lead levels usually can be traced to lead paint, lead pipes and motor vehicle exhaust. If the site once held a building, fence or other painted structure, paint flakes may have entered the soil. Our common use of wood here in the Northwest means that painted surfaces are also more common than in some regions. The worst cadmium contamination in our area is near or downwind from the old Tacoma smelter. Cadmium in soil may also have come from car exhaust, commercial fertilizers and other sources. Arsenic is another by-product of smelting metals. It also may accumulate where coal was burned or where arsenic-containing pesticides have been sprayed. Now that we realize the danger, much less heavy metal contamination is happening. New paint and pipes don't contain lead. Unleaded gas is widely used. The Tacoma smelter is history and factories and coal- burning power plants are carefully engineered and closely monitored to minimize pollution. Fertilizers and pesticides don't add to the problem the way they did in the past. COMMUNITY HORICULTURE FACTSHEET #22 HEAVY METALS IN THE GARDEN 500 SW 7th Street, Suite A200 Renton, WA 98055-2983 206-205-3100!TTY-TDD 296-5242 FAX 206-296-0952 http://king.wsu.edu Even sewage sludge, which often contained high levels of heavy metals, is usually relatively free of…