Just screening blood is not sufficient. "If it's true that there is no discernible threshold for intellectual impairments, as our studies are showing," suggests Dr. Lanphear, "then our focus must shift away from waiting until a child has been unduly exposed, to primary prevention. First thing I would tell parents: Primary emphasis should be on screening housing and reducing exposures; screening blood should be considered a safety net."
The prevailing wisdom (so far, at least) is that most cases of lead poisoning are the result of exposure in homes, primarily when children in older buildings eat peeling lead paint chips (which have an especially high concentration) that have fallen on the floor or are chipping off walls or window frames. Exposure also occurs when teething toddlers chew on windowsills, doors -- even radiators -- and/or when kids ingest or inhale lead-tinged dust particles that get on their toys, on food that's been stored uncovered, or on the floors on which they're playing.
Is Your Home a Hazard?
Don't ignore your own walls because you think this type of stuff only happens in substandard housing. Lead dust can exist in the most meticulously maintained home and can even be a significant issue in a newly renovated apartment because of the disturbance of old paint. So the antebellum dream house you've been fantasizing about restoring in Atlanta, or that "perfect" 1920s bungalow in Portland? It may turn out to be more of a nightmare for your kids if you don't take precautions.
Sheldon Whitehouse, former attorney general of Rhode Island, found this out the hard way. He and his wife renovated their house in a lovely historic district in Providence. All was well until a routine blood test post-renovation resulted in the stunning news that his children had elevated blood lead levels.
According to recent CDC research, remodeling and repainting projects may be the cause of as much as 10 percent of all lead poisoning in American children. In fact, over the last decade, doctors have been reporting a real shift in the demographics of lead-poisoned children.
Dr. Lanphear notes that only a decade ago, children from the poorest neighborhoods comprised about 90 percent of the cases treated at Cincinnati Children's Hospital Medical Center. Now, he says, a good 50 percent of exposed children treated at his hospital come from affluent families who have been inadvertently poisoned when their old homes were renovated.
So please, do not assume that your child will be immune from lead's deadly effects just because you have nice digs. Nor is it safe to believe that you've protected your child simply because you kept him out of your abode during the renovation itself; lead levels can be persistently high even after the job is completed. (By the way, if you're pregnant, you need to be just as concerned: Lead ingested during pregnancy can have devastating results on the baby's development.)
Lead Outside the Home
There are, of course, other sources of lead intake besides paint, but they tend to be more elusive. According to the American Academy of Pediatrics, for kids with low, but still elevated, blood levels (between 10 and 14 BLLs), the source of the lead exposure is often a mystery.
One possibility is dirt from sidewalks, parks, playgrounds, and building foundations. Howard Mielke, MS, PhD, has been researching the incidence of lead in urban soil over the two decades since his own daughter's high blood lead levels were traced to the soil in her daycare center's outdoor play area. He and other scientists conducting studies in cities as diverse as Baltimore, Minneapolis, and New Orleans, and the results suggest that, in traffic-congested urban areas, "many children face their greatest risk for exposure in the yards around their houses and, to a lesser extent, in the open spaces such as public playgrounds in which they play."
While there's considerable debate as to the sources of urban soil lead -- from traffic exhaust to building paint residue and fallout from industrial pollution -- there's no question that its buildup can be substantial. A Chicago residential neighborhood study documented median soil lead levels more than four times the acceptable EPA standard, causing health professionals at the renowned Children's Memorial Hospital to warn parents that protecting kids from lead in soil should be as important as safeguarding them against paint-based sources.
Lead in Your Water?
Finally, there's the issue of lead found in water. Many cities, including Atlanta, New York, Pittsburgh, Philadelphia, and New Orleans, add an anticorrosive called orthophosphate to the water supply and have achieved great success in reducing the lead content of water found in older buildings, but there are no guarantees. Lead can still leach in from old pipes and from brass fittings on faucets or pipes in your building, particularly if you are using hot water. Washington, D.C., residents are still reeling from the news that two-thirds of tested homes had water exceeding EPA lead limits (some by as much as 36 times), a result of additives which corroded lead pipes.