In the air that they breathe: Lead still a problem for US kids
Lead poisoning remains a major health hazard for America's children.
When Karen and Bob Brantley found the lovely old Baltimore County, Md.,
farmhouse for rent in 1992, it seemed like a dream come true. The 25-acre
property had woods, a pond nearby, and room for a dog and their kids, Tommy,
Kaitey, and Bobby, who was born shortly after they moved in.
Christian, their fourth child, came along in 1996. He was a calm and happy
kid at first. But last year, when Christian was about 18 months, he started
eating dirt, a condition called pica that the family's pediatrician feared
might be a sign of lead poisoning. Testing revealed that his blood lead
level was 19 micrograms per deciliter, nearly twice the level at which
a
child is considered at risk.
Karen Brantley was shocked. "I'm a stay-at-home mom," she says. "I watch my
children." Like many middle-class parents, the Brantleys did not know that
lead poisoning remains the most significant environmental health hazard
for U.S. children. An estimated 1.7 million children are already affected by
lead from old paint, water pipes, soil, and other sources, according to
the Environmental Protection Agency. This breaks down to 4.4 percent of all
children and a full 22 percent of African-American kids who live in older
homes.
Some 890,000 of all children affected are under age 6, when the brain and
central nervous system are most vulnerable. At the same time, scientists
have determined that lead levels once considered safe can actually dampen IQ
scores and cause lifelong learning disabilities, hyperactivity,
attention-deficit disorders, and aggressive behavior. "I don't know of
any other disease as disabling as lead poisoning that strikes 1 in 25 children
that people wouldn't be screaming about," says Herbert Needleman, pediatric
psychiatrist and lead expert at the University of Pittsburgh.
Taking aim
Now, in an effort to hold the lead industry financially
responsible, a number of prominent personal-injury attorneys and about
a dozen state and city prosecutors are taking legal aim at paint, pigment, and
gas-additive makers for the damage lead has done. In addition, the
Environmental Protection Agency is meeting this week in Washington to
discuss tightening the reporting requirements for industries that release
the metal into the environment.
Doctors have known of lead's toxic effects since the turn of the century. In
1904, the first article about childhood lead poisoning from paint appeared
in an Australian medical journal. France and Austria banned the interior use
of lead paint in 1909, but a U.S. ban on residential use didn't come until
1978. At that time, studies showed that 88 percent of U.S. children had
elevated lead levels. As lead additives were phased out of gasoline, and
lead poisoning dropped dramatically, many believed the problem was solved.
"I wouldn't have thought, 20 years ago, that we'd still be seeing lead
poisoning at this point in time," says Omer Berger, director of the lead
clinic at Children's Hospital Medical Center in Cincinnati.
In the late 1970s, concern about lead focused on its use in gasoline and on
kids eating paint chips. But today the biggest hazard for children is the
fine, microscopic lead in house dust that results from the breakdown of the
lead-based paint widely used in pre-1978 homes. About 64 million homes still
contain lead paint, and 5 million to 15 million have been identified by the
U.S. Department of Housing and Urban Development as very hazardous.
Poor and minority children are more likely than more affluent or white
children to live in these substandard homes, but children at all income
levels are failing to get tested. While children on Medicaid are supposed to
be screened for lead at the age of 1 or 2, fewer than 20 percent nationwide
have been tested. (The state of Missouri filed suit last month against
Healthcare USA of Missouri LLC and Prudential Health Care Plan Inc., two
Medicaid providers, charging that the plans failed to screen their St. Louis
pediatric patients for lead as federal law requires. Other states are
considering similar action.) Children from well-off families are rarely
checked as toddlers, though some school systems require screening. "But if
you screen at school entry, it's too late," says Katherine Farrell of the
Anne Arundel County (Md.) Health Department. "The damage is done between 9
and 18 months."
At the same time, the amount of lead regarded as hazardous has dropped
steadily over the past three decades, from 60 micrograms per deciliter of
blood to 10. And doctors are finding that even levels below 10 can be
harmful. A Boston study of 148 children - many of them from relatively
affluent families - showed that those with low lead levels at age 2 had
decreased intellectual performance at age 10.
Links to crime
Children with elevated lead levels, Pittsburgh's Needleman
has found, were seven times as likely to drop out of high school as other
children, and six times as likely to have a reading disability. "We estimate
that 20 to 30 percent of the special education caseload in urban centers
results from lead poisoning," says Ruth Ann Norton, executive director of
the Coalition to End Childhood Lead Poisoning. For decades, teachers and
parents have reported disruptive behavior in lead-poisoned kids. In 1996,
Needleman published the first rigorous study demonstrating that boys with
elevated lead levels were more likely to engage in bullying, vandalism,
arson, shoplifting, and other delinquent behaviors. Needleman is now trying
to assess what portion of the juvenile criminal population suffered elevated
lead levels as children; his theory is that a reduction in lead poisoning
would result in less crime.
The precise mechanism by which lead affects behavior and damages the brain
is not clear. Because lead is chemically similar to calcium, it can disrupt
brain mechanisms that depend on calcium, like neurotransmitters that play a
role in mediating responses to stimuli. The lead may also disrupt a process
called neural pruning, in which the maturing brain weeds out some of a
child's neural circuits, the connections between brain cells. Inadequate
neural pruning may cause impulsiveness, hyperactivity, and diminished
attention span. "Lead is potentially one preventable cause associated with
the rise in attention-deficit disorders or ADD," says David Bellinger, a
lead expert at Children's Hospital in Boston. Poor nutrition, particularly
calcium and iron deficiencies, contributes to lead uptake. So does hunger.
"If people are exposed to lead on an empty stomach, they absorb much more
lead," says Kathryn Mahaffey, a scientist at the EPA.
Once ingested, lead, like calcium, is stored in the bones. During pregnancy,
when the bones release calcium into blood, the lead is released with it,
sometimes affecting the baby's brain development. And new research released
last month by Ellen Silbergeld, a University of Maryland scientist, shows
that blood lead levels rise at menopause; as a result, some women experience
hypertension and cognitive dysfunction.
The only known way to remove lead from the body is with chelation therapy, a
treatment with chemicals that grip heavy metals, allowing them to be
excreted. But chelation also lowers iron levels and may remove the lead too
late to make a difference. The National Institutes of Health will conclude a
three-year study next month that is expected to show whether chelation
prevents lead-induced intellectual damage.
Cost effects
Since treatment is difficult, government officials and
physicians are recommending a process called lead abatement, which involves
encapsulating lead paint or stripping it out completely. A study done in
1991 for the Centers for Disease Control and Prevention showed that cleaning
up lead in homes would save the nation about $62 billion in medical and
special education costs over 20 years. But abatement doesn't come
cheap - Housing and Urban Development pegs it at $2,500 to $10,000 or more per
home. Housing Secretary Andrew Cuomo recently awarded state and local
governments $56 million for lead poisoning control, most of which will go
toward abatement. That only begins to cover the staggering costs of fixing
millions of homes, however, and some fear that lead abatement will make
affordable housing more scarce.
Meanwhile, faced with Christian's medical expenses and the moving costs of
leaving the lead-contaminated house, Bob Brantley began calling lawyers. He
reached the law firm of Peter Angelos, a personal-injury specialist in
Baltimore, who had a major role in the successful tobacco litigation.
Angelos included the family in a lawsuit he was filing against paint,
pigment, and gasoline-additive manufacturers. (He has also filed a class
action on behalf of a million Maryland homeowners who have been forced to
pay abatement costs for their homes.)
In October, the Rhode Island Attorney General's Office filed suit against 10
companies involved in the distribution of lead products in Rhode Island.
"The Rhode Island lawsuit is attempting to make scapegoats out of
responsible corporations," says Tim Hardy, a Washington, D.C., lawyer
representing NL Industries, one of the defendants in the Rhode Island and
Maryland cases. Hardy argues that although the companies realized in the
1930s that lead-painted toys could be harmful to children (who were likely
to chew on them), they did not know that painted walls were a potential
threat. Indeed, he says, in its peak years of use - the first few decades of
this century - lead paint was considered a superior product, since it was more
durable than other available paints.
But with prosecutors in Illinois, Michigan, Ohio, New York, Louisiana, and
other states considering similar lawsuits, the lead industry worries its
arguments may fall on deaf ears. "The lawyers involved in these lawsuits are
the same people who led the state attorneys general against the tobacco
industry. The reason those companies settled is because they were
overwhelmed by the number of lawsuits," Hardy says. He fears the lead
industry may meet tobacco's costly fate. "Attorney generals have realized
the power to enforce consumer protection laws," says Jack McConnell, an
attorney assisting the Rhode Island Attorney General's Office. "My guess is
this will take a very similar path to tobacco."
Today, the Brantley family lives in a lead-free home in a Baltimore suburb.
Christian's blood lead levels have dropped, but the symptoms remain. "He
attacks his brother Bobby until he draws blood," his father says. "He tries
to gouge out his eyes." The Brantleys worry every day about Christian's
future, not only whether he will have a lower IQ or cognitive impairment
resulting from his lead poisoning but how he will learn to control his
behavior. "Christian," his father says, "is violent way beyond what a normal
3-year-old should be. What will he be like at 12? At 15?"
US NEWS AND WORLD REPORT
Science & Ideas 12/20/99
By Amanda Spake and Jennifer Couzin