Heavy metal Lead's legacy lives on in landfills

By Thomas Wilson
star staff

  It is the only metal Superman's X-ray vision could not penetrate.
  Lead was used by the ancients and is even mentioned by name in the books of Exodus and Numbers in the Old Testament. While banned for use in most motor fuels and forged materials that can affect human health, lead continues to affect the environment as older buildings are felled and lead-containing debris is dumped into hazardous waste landfills around the nation.
  Lead exposure affects the human nervous, endocrine, and reproductive systems. Years of use as an additive in paint and gasoline puffed tons of lead debris into lungs and bloodstreams of humans and animals.
  Construction debris containing lead material has been collected from demolition of the North American Rayon Corporation manufacturing facility during building of the new Wal-Mart Supercenter. Demolition debris containing lead and asbestos materials remains covered in black sheeting at the supercenter construction site awaiting disposal by developers.
  The presence of lead also raised a red flag for the city of Elizabethton shortly after the Tennessee Department of Environment and Conservation began a preliminary assessment of the Sugar Hollow Dump site in 1997.
  In 1999, TDEC launched an investigation after finding 60 cubic yards of industrial metal and sludge at the site. TDEC officials reported metal sludge found near the top of the landfill tested "characteristically hazardous for lead" and identified the waste as a product of Mapes Piano Strings. The discovery came two years after the Environmental Protection Agency requested TDEC conduct a preliminary assessment of the site.
  The Sugar Hollow property was leased by the city of Elizabethton for use as a solid waste dump site in 1958. The dump was closed by the city in 1972. The city will pay out a $650,000 recapping fee after entering into the state's Voluntary Cleanup Oversight and Assistance Program and is tasked with monitoring the site by TDEC.
  Studies conducted by the U.S. Centers for Disease Control found lead can affect almost every organ and system in the human body. Lead most directly affects the central nervous system, particularly in children and can also damage the kidneys and the reproductive system. The effects are the same whether lead is breathed or swallowed, according to health studies compiled by the CDC.
  Twenty years ago, motor vehicle traffic ranks as the major contributor of lead emissions to the air. In the early 1970s, EPA set national regulations to reduce the lead content in gasoline. In 1975, unleaded gasoline was introduced for motor vehicles equipped with catalytic converters.
  The Clean Air Act Amendments of 1990 banned the sale of leaded gasoline. The Federal Hazardous Substance Act banned children's products that contain hazardous amounts of lead.
  As a result of regulatory efforts to remove lead from gasoline, the EPA reported in 2001 that emissions of lead from the transportation sector declined 95 percent between 1980 and 1999 while levels of lead in the air decreased by 94 percent between 1980 and 1999. Transportation sources, primarily airplanes, now contribute 13 percent of lead emissions.
  Lead itself does not break down, but lead compounds are changed by sunlight, air, and water. When lead is released to the air, it can travel long distances before settling to the ground.
  Lead-based paint was once slathered on walls of residential and commercial buildings around the country until the metal additive was banned by the federal government during the mid-1970s. EPA assessments find much of the lead found in soils of the nation's inner cities comes from old houses painted with lead-based paint.
  Lead dust can form when lead-based paint is dry scraped, dry sanded, or heated. Dust also forms when painted surfaces bump or rub together. Settled lead dust can re-enter the air when people vacuum, sweep, or walk through it.
  A National Health and Nutrition Examination survey conducted in the late 1990s reported a 78 percent decrease in the levels of lead in people's blood between 1976 and 1991. The survey attributed the dramatic decline to the switch from leaded to unleaded gasoline as well as the removal of lead from soldered cans.