Lead Is All Around Us

Despite Historical Warnings, Toxic Element Remains Ubiquitous

By Julie L. Jones
December 2007

It’s in our car batteries, on our bridges, lining electric cables and peeling from old walls. It used to be in canned food containers and gasoline and toy soldiers. And it’s in our children’s toys.

But why?

USES OF LEAD

Despite its dangers, lead’s low cost, malleability, pigment and flavor earned it a prominent place in history. The ancient Romans extensively mined for and smelted lead, drank water from lead-lined aqueducts, wore lead-tainted makeup and consumed wine preserved and sweetened with lead, which likely contributed to upper class infertility, author Jack Lewis pointed out in a 1985 EPA Journal article, “Lead Poisoning: A Historical Perspective.”

Lead was used as a colorant for 18th century powdered wigs, and has also served as an agent to prevent steel corrosion and as a bright white and brightly colored pigment in paints, Stephen Sides, vice president of environmental health and international affairs for the National Paint & Coatings Association, told TDmonthly Magazine. He noted that the toy industry unfortunately picked it up for its use as a bright pigment, ideal for red, orange and yellow shades.

RESTRICTIONS CROP UP

Is Legislation Protecting U.S. Intelligence?

“On average, children whose blood lead levels rise from 10 to 20 mcg/dL lose two to three IQ points,” Dr. Dana Best said in September testimony before a Senate subcommittee. The loss of IQ points between 5 and 10 mcg/dL is even greater, at one point for every one mcg/dL.

But an American Academy of Pediatrics representative pointed out that BLLs in children have fallen since the 1970s, from a median BLL of 15 mcg/dL in 1- to 5-year-old children from 1976 to 1980 to an average BLL for U.S. children of 2 to 3 mcg/dL.

General Motors began manufacturing Ethyl Gas — fuel made with tetraethyl lead — in 1921 because it increased a vehicle’s performance and silenced “engine knock.” But factory workers suffered psychotic episodes and even death, according to “History of Lead Poisoning in the World” by Dr. Herbert L. Needleman, a University of Pittsburgh School of Medicine professor.

Though standard-setting groups pursued safety initiatives from the 1920s, lead in gasoline wasn’t outlawed until 1986, Sides said.

The first official lead restrictions for paint were released in 1954 by the American Standards Association, which learned from the American Academy of Pediatrics that children might be exposed to lead by chewing on painted items. The Z66.1 standard, lowered in 1963 from 1 to 0.5 percent lead in paint, became law in 1972.

But even before then, the industry had alternatives such as titanium dioxide, used in place of lead carbonate in paint today. War also invited substitutes, since “lead wasn’t around for pigment,” Sides told TDmonthly.

The 1978 ban of lead paint coatings on toys and certain other children’s products, based on testimony by Dr. J. Julian Chisholm of Johns Hopkins, set lead limits at trace amounts of no more than 0.06 percent by weight, or 600 parts per million, under the Federal Hazardous Substances Act overseen by the CPSC.

HOW MUCH IS TOO MUCH?

Can Lead Poisoning Be Treated?

For severe cases of lead poisoning, doctors might turn to chelation therapy, during which an agent is used to bind lead in the bloodstream so that it can be excreted from the body. “It decreases the potential of the damage, but it does not reverse the damage,” Dr. Best cautioned, noting that the process comes with its own dangers.

But now the AAP is lobbying for a lead limit of 0.004 percent, or 40 parts per million, and Congressional committees are considering new laws.

The limit’s low, so why not cut lead out completely?

“It’s part of the earth’s crust,” Sides informed. The recommended 40 ppm is the top-range amount of lead found in uncontaminated soil.

Numbers aside, the effects of lead are virtually irreversible, and any elevated blood lead level can be devastating.

“There is no safe level of lead in a human,” Dr. Dana Best, an assistant professor of pediatrics at George Washington University School of Medicine, told TDmonthly. “Every level greater than zero means that there has been some damage,” which could lead to poor coordination, literacy problems and delinquent behavior.

“The only thing that we’re ever going to be able to do is prevent it,” she concluded.

Bottom line? Despite regulation and avoidance, lead will always be with us. The steps we take with the knowledge we have will ultimately determine how it affects our lives.