Lead And Your Kids

No unanimity:

While there is a strong consensus that lower levels of lead cause damage, there is no unanimity. Studies financed by the lead industry have found little damage at low levels, and one independently funded study found that early intelligence losses associated with lead may fade in later years. "You see tremendous inconsistencies among the results," says Rosalind Volpe, a consultant with the International Lead Zinc Research Organization, an industry-sponsored group. The key health statistic, according to Jeffrey Miller, spokesman for the Lead Industries Association, is that average blood levels have dropped dramatically in recent decades, from 17 Fig/dl in 1978 down to about 6 jig/dl now. "One might get the sense it's a billowing epidemic, when in fact the opposite is true," he says.

It's a fair point, which makes one wonder: if lead is so bad, why aren't half of today's adults suffering the effects of childhood lead poisoning? The answer is that many probably are, but couldn't possibly know it. "I guess we all might have been a little smarter than we turned out," says David Bellinger, a lead researcher at Harvard University. "It's hard to tell if someone goes from 140 IQ to 135."

The changing notion about how kids get poisoned is altering beliefs about who gets poisoned: if children can get lead poisoning without eating peeling paint, they can get it without living in dilapidated housing. The Children's Hospital in Boston reports that from 1987 to 1990, 40 percent of its infant-poisoning cases resulted from victims ingesting dust while the family, often well-to-do, renovated an old house. The daughter of a financial consultant and a management consultant became sick from renovations on an old farmhouse in Concord, Mass. Paul and Gerry Francoeur's 3-year-old daughter, Heather, seems to have gotten lead poisoning from playing in her sandbox, which apparently became contaminated with lead dust after her father sanded paint off the house's exterior.

The Francoeurs were lucky because they live in Massachusetts, the only state that requires mandatory testing of children for lead poisoning. Several states and cities have aggressive programs to screen innercity children for lead poisoning. But all those programs together in 1985-86 tested just 800,000 kids, about 4 percent of children under age 6. And pediatricians of middle-class kids test even less frequently than those of the poor.

It takes strikingly little lead to cause lead poisoning. A child can become severely lead poisoned (60-80 ug/dl) by eating one milligram of lead-paint dust-equivalent to about three granules of sugar-each day during childhood. To achieve blood-lead levels of 35 ug/dl, a child would have to eat just the equivalent of one granule of sugar a day. That's why a child can become ill merely by regularly touching a windowsill and then sucking his thumb. Why is lead so toxic? The body, in effect, mistakes it for calcium. The lead attaches to and disrupts enzymes essential to functioning of the brain and other cells. Because lead is an element, it never decomposes into another, more easily tolerated, substance. While it can be removed from the bloodstream through chelation, most of the lead that is absorbed into a child's brain, it's there, literally, forever.