Helping Parents Prevent Lead Poisoning. ERIC Digest.
by Binns, Helen J. - Ricks, Omar Benton
Lead poisoning occurs when too much lead gets into the body. Children
are at greater risk than adults because children absorb lead more readily
than adults, and a small amount of lead in children's bodies can do a great
deal of harm. Lead can cause irreversible damage to a child's developing
brain (Agency for Toxic Substances and Disease Registry [ATSDR], 1995;
Bellinger et al., 1992; Dietrich et al., 2001). The effects of lead poisoning
on children can therefore have a significant, long-lasting impact on learning
and behavior (Banks et al., 1997; Environmental Protection Agency [EPA],
1999; Satcher, 2000; Schwartz, 1994).
One measure of lead in the body is the blood lead level (BLL), measured
in micrograms of lead per deciliter of blood (micrograms/dL). Nearly everyone
has a measurable BLL. The Centers for Disease Control and Prevention (CDC)
says that BLLs of 10 micrograms/dL or above are cause for concern (CDC,
2000a). However, even at BLLs below 10 micrograms/dL, lead can impair development
(American Academy of Pediatrics [AAP], 1998; Banks et al., 1997; Bellinger
et al., 1992; Landrigan, 2000; Lanphear et al., 2000; Schwartz, 1994).
This Digest summarizes some causes and effects of childhood lead poisoning
and suggests some lead poisoning prevention strategies that parenting educators
can share with parents.
WHAT IS KNOWN ABOUT CHILDHOOD LEAD POISONING?
Occurrence in children. The prohibition of many lead products in the
United States--especially leaded gasoline, residential lead paint, and
lead solder in canned foods--has drastically reduced the average BLL of
U.S. children since 1978 (CDC, 2000a). However, the CDC estimates that
890,000 children under 6 years of age may still have unsafe BLLs (CDC,
n.d.). Moreover, urban and rural areas with older homes have high rates
of lead poisoning (CDC, 2000a; Norman et al., 1994). A recent national
survey of homes in which young children live estimated that lead hazards
existed in 94% of the homes built before 1940 and in 87% built from 1940
to 1959 (Housing and Urban Development [HUD], 2001). The risk for elevated
BLLs is disproportionately high in low-income and minority communities,
even after home age is taken into account (CDC, 2000b).
Symptoms and Effects for Individuals. Lead poisoning may not affect
all children in the same ways. Most children with elevated BLLs lack any
physical symptoms. The few who do show symptoms may have very subtle, common
symptoms such as headaches, stomachaches, sleeping problems, and irritability
(ATSDR, 1995; Banks et al., 1997). The longer-term effects of lead poisoning
can include lowered IQ, reading and math disability, short-term memory
loss, hearing problems, hyperactivity, and a host of other cognitive and
behavioral problems (Lanphear et al., 2000; Schwartz, 1994). Available
evidence suggests that the effects of lead poisoning on cognitive development
and behavior are long term and irreversible (Burns et al., 1999; Dietrich
et al., 2001; Rogan et al., 2001). If left untreated, high BLLs can cause
slowed growth; damage to the kidney, brain, and nerves; and, in extreme
cases, death (CDC, n.d.; EPA, 1999). Children under 2 years of age are
at the highest risk for lead poisoning, since they tend to put non-food
items in their mouths. In addition, lead exposure at this age can be particularly
harmful to children's cognitive and behavioral development (Bellinger et
al., 1992; Dietrich et al., 2001).
Broader Social Effects. Many controlled observation studies relate higher
BLLs to lower IQ scores, even at BLLs below the CDC level of concern (Banks
et al., 1997; Lanphear et al., 2000; Lewendon et al., 2001; Schwartz, 1994).
The impact on IQ may be small for an individual child, but the effects
on the population as a whole may be much broader: an estimated two- to
fourfold increase in the number of children categorized as "mentally retarded"
and a similar reduction in the number of children categorized as "gifted"
(Banks et al., 1997). Low-level lead poisoning may therefore increase special
education costs, in addition to medical costs (Banks et al., 1997; Satcher,
2000). Moreover, numerous studies have demonstrated that children with
lead poisoning are more likely to have long-term behavioral problems, including
a higher likelihood of delinquent behavior (Banks et al., 1997; Dietrich
et al., 2001; Lewendon et al., 2001).
HOW CAN PARENTS PREVENT LEAD POISONING?
Parenting educators can stress how important it is for parents to be
aware of the risk factors for lead poisoning and to minimize their child's
exposure before poisoning occurs.
Risks at Home. Most exposure to lead occurs at home. Older homes often
have leaded interior or exterior paint. Dust from the deterioration of
this paint can create a lead hazard. The most common sites of risk in the
home are at windows, porches, or entryway areas. Parents can be advised
to keep these areas clean and prevent children from playing in these areas
unless the risk of exposure is low. Renovations that disturb leaded paint
can release dust in a home and should not be attempted without expert advice
and training. Soil around older homes may be contaminated with lead from
paint residue, and soil along busy streets may have leaded gasoline residue.
At-risk children may also live in areas with industries nearby such as
lead smelters or battery recycling plants that have emitted lead dust into
the air and soil (ATSDR, 1995).
Parents can be advised to check for peeling or chipping paint in their
home, clean those areas with soap and water, and make arrangements for
safe, professional repair. Local public health agencies can sometimes help.
Parents who are concerned that their home may pose a risk can have certified
lead inspectors or risk assessors check the amount of lead residue in paint
and dust throughout their home and in their soil. These individuals may
be able to tell parents if the lead in their home presents a risk, offer
suggestions about the least intrusive ways to remove any risks, and recommend
certified lead abatement specialists, if necessary (CDC, n.d.; EPA, 1999;
see also http://www.leadlisting.org to locate abatement professionals).
Lead found in water tends to occur in much lower concentrations than
lead in paint or soil, and it therefore presents much lower risk. The major
source of lead in water is the solder found in pipes in older homes. Before
using water for cooking or drinking, parents are advised to: (1) run tap
water for 15 to 30 seconds if it has not been used for a few hours; and
(2) use cold water, which leaches lead more slowly than warm or hot water
Risks from Work. Parents with jobs that involve contact with Lead--such
as law enforcement, plumbing, automobile repair, construction, and mining--risk
bringing lead dust home on their clothes and passing it on to their families.
These parents can be advised to change clothes before coming home, keep
work clothes separate from house clothes, and wash them separately (ATSDR,
1995; EPA, 1999; Occupational Safety and Health Administration [OSHA],
Healthy Habits. Children with iron deficiency or with low daily calcium
intake absorb lead more readily, so parents will want to make sure that
their child's diet contains sufficient--although not excessive--amounts
of these nutrients (ATSDR, 1995; AAP, 1998; EPA, 1999). Parents cannot
prevent their children from putting things in their mouths, but parents
can prevent them from reaching potentially dangerous items and teach them
to wash their hands before eating. These measures are parts of the solution,
but they are insufficient to prevent lead poisoning if the environmental
risk is still present.
Certain leaded products imported from countries that have not banned
the use of lead are available in the United States--including foods, dyes,
cosmetics, and folk medicines (CDC, 1998; Lynch et al., 2000). It is difficult
for federal and state regulatory authorities to prevent the importing of
all unsafe products. It is important for parents to know the contents of
products their families use and to avoid using products they suspect are
not approved by the Food and Drug Administration (http://www.fda.gov).
Medical Checkups. Elevated BLLs often go undetected until they get very
high. Only 19% of children ages 1-5 who were on Medicaid received BLL tests
in 1998, even though children on Medicaid accounted for a large majority
of the instances of elevated BLLs among U.S. children (CDC, 2000b). Parents
of children at risk for lead exposure can be advised to have their children
routinely screened for rising BLLs--young children should be screened several
times before the age of 3--at least at ages 12 months and 24 months (EPA,
1999; AAP, 1998).
The prevention of lead poisoning is the focus of many national, state,
and local agencies and organizations; parents also play a major role. Helping
parents get informed is an important first step. There are many sources
of high-quality parent-friendly resources; the local public health agency,
the National Lead Information Center at 1-800-424-LEAD, and the Alliance
to End Childhood Lead Poisoning Web site at http://www.aeclp.org are just
FOR MORE INFORMATION
Agency for Toxic Substances and Disease Registry (ATSDR). (1995). CASE
STUDIES IN ENVIRONMENTAL MEDICINE: LEAD TOXICITY [Online]. Available: http://www.atsdr.cdc.gov/HEC/HSPH/
American Academy of Pediatrics (AAP). (1998). SCREENING FOR ELEVATED
BLOOD LEAD LEVELS [Online]. Available: http:// www.aap.org/policy/re9815.html.
Banks, E. C., Ferretti, L. E., & Shucard, D. W. (1997). Effects
of low level lead exposure on cognitive function in children: A review
of behavioral, neuropsychological and biological evidence. NEUROTOXICOLOGY,
Bellinger, D. C., Stiles, K. M., & Needleman, H. L. (1992). Low-level
lead exposure, intelligence and academic achievement: A long-term follow-up
study. PEDIATRICS, 90(6), 855-861.
Burns, J. M., Baghurst, P. A., Sawyer, M. G., McMichael, A. J., &
Tong, S. L. (1999). Lifetime low-level exposure to environmental lead and
children's emotional and behavioral development at ages 11-13 years: The
Port Pirie cohort study. AMERICAN JOURNAL OF EPIDEMIOLOGY, 149(8), 740-749.
Centers for Disease Control and Prevention (CDC). (1998). Lead poisoning
associated with imported candy and powdered food coloring: California and
Michigan. MORBIDITY AND MORTALITY WEEKLY REPORT, 47(48), 1041-1043.
Centers for Disease Control and Prevention (CDC). (2000a). Blood lead
levels in young children: United States and selected states, 1996-1999.
MORBIDITY AND MORTALITY WEEKLY REPORT, 49(50), 1133-1137.
Centers for Disease Control and Prevention (CDC). (2000b). Recommendations
for blood lead screening of young children enrolled in Medicaid: Targeting
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Environmental Protection Agency (EPA). (1999). PROTECT YOUR FAMILY FROM
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G. G. (2001). The effect of chelation therapy with succimer on neuropsychological
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