Thank you for the opportunity to present testimony to you today regarding the effects of lead on children, pregnant women and nursing mothers. I am a board-certified pediatrician and preventive medicine physician, with expertise in pediatric environmental health. I hope that I can provide the committee with some useful and important information about lead, lead poisoning, and current research on the topic.
Children’s Hospital is a 279-bed pediatric inpatient facility located in the District of Columbia. For more than 130 years, Children’s has served as the only provider dedicated exclusively to the care of infants, children, and adolescents in this region. It is our mission to be preeminent in providing health care services that enhance the well-being of children regionally, nationally, and internationally. The Children’s system includes a network of nine primary care health centers located throughout the city, and a number of pediatric practices throughout the region, providing stable medical homes for thousands of children. We operate numerous regional outpatient specialty centers in Maryland and Virginia, providing access to high quality specialty care in the communities we serve. We are proud to be the region’s only Level I pediatric trauma center. Children’s Hospital serves as the Department of Pediatrics for George Washington University School of Medicine and Health Sciences, and runs a highly-respected pediatric residency program, providing education and experience to the next generation of pediatricians, pediatric subspecialists, and pediatric researchers. We conduct significant research within the Children’s Research Institute, with funding from the National Institutes of Health, the Health Resources Services Administration, the Department of Defense, the US Environmental Protection Agency, and many other public and private funders.
Lead’s Effects on Children, Pregnant Women, and Nursing Mothers
Introduction and a Brief History.
Lead is a bluish-white metal of atomic number 82. Its isotopes are the end products of each of the three series of naturally occurring radioactive elements. It is soft, malleable, and resistant to corrosion, which makes it ideal for use in plumbing, pottery, tools, etc. Alloys of lead include pewter and lead solder.1
Use in ancient Rome. Lead pipes used as drains from the Roman baths and bearing the insignia of Roman emperors, are still in service.1 Debate over the contribution of lead poisoning to the fall of the Roman Empire persists, but it is generally accepted that lead was widely used in plumbing, pottery, and cooking vessels. One potential source of lead poisoning in Roman times was the practice of boiling unfermented grape juice in lead pots. The resulting sugar and lead-laden syrup was added to wine to improve taste. The Romans recognized that lead was harmful, and identified the dangers of breathing fumes from lead furnaces and drinking water from the areas of lead mines; the connection of lead cooking vessels to lead poisoning is less well-described.2
Use in gasoline. Tetraethyl lead, the “antiknock” compound in leaded gasoline, was first described in 1854. In 1921, the emerging auto industry found it to be an effective, inexpensive gasoline additive that reduced engine “knock”, a pernicious problem. Even in 1921 the poisonous effects of lead ingestion had been described and many public health authorities warned against this use of tetraethyl lead, particularly since other effective anti-knock gasoline additives were available. Nevertheless, due to cost reasons, tetraethyl lead was used. In 1922 the US Public Health Service warned of the dangers of leaded fuel, and the scientific community added further concerns. In 1923, Thomas Midgley, the primary proponent of leaded fuel, suffered from acute lead poisoning and several workers at plants that made tetraethyl lead died.
In 1926, a committee appointed by the US Surgeon General to review the harms of tetraethyl lead called for regulation of the product and for further studies funded by Congress. Those studies were never funded and never performed. Further evidence of the harms of lead continued to be published, but leaded gasoline was not phased out until 1986, and lead-containing motor fuel additives were not banned until 1996.3 This belated public health success resulted in a significant drop in the blood lead levels of US children: in 1976, when the standards were implemented, the average blood lead level in children was 15 mcg/dl; in 1991, those levels had dropped to 3.6 mcg/dl.1
Use in paint.4 Lead has been used for centuries to make paint whiter, last longer, and cover better. The harm from lead in paint to children was first noted in the English literature in 1887.5 In 1904, child lead poisoning was linked to lead-based paints,6 and as a result, many countries began banning lead-based interior paints. Lead continued to be used in paints in the US, however, including paint used on cribs. In 1914 the death of a Baltimore boy due to lead poisoning from chewing on his crib railing was described, and other cases continued to be reported.7, 8 In 1922 the League of Nations banned lead-containing interior paint but the United States did not adopt the ban. In 1943 it was reported that eating lead-containing paint chips causes physical, neurological, behavior, learning and intelligence problems in children. Finally, in 1971, the Lead-Based Paint Poisoning Prevention Act was passed and finally implemented in 1977. As a result of these delays in banning leaded paint, many US homes still contain lead paint. With the banning of leaded fuel, lead paint is now the primary source of childhood lead poisoning in the US.
Lead in water. Federal regulation of drinking water quality began in 1914, when standards for bacteriological levels were set; lead as a water contaminant was not regulated until much later, in 1962.9 Most of the lead in water comes from industrial releases, urban runoff, and atmospheric deposits. While these sources of environmental lead are small, in comparison to other sources such as leaded gasoline, they can be significant, depending on water conditions. pH, grounding of household electrical systems to plumbing, and water additives can increase the leaching of lead from pipes and increase the solubility of the leached lead.3 In most cities in the US, lead in tap water is due to the corrosion of lead-containing materials, such as lead pipes, in water distribution systems and household plumbing.10 In terms of lead in water as a source of childhood lead poisoning, discussions of oral lead ingestion do not separate dust sources or paint chips from lead in the water supply, making it extremely difficult to discriminate between lead poisoning from household paint and lead poisoning from lead-contaminated water supplies. It is highly likely that lead-contaminated water can contribute to lead poisoning of children. However, no studies of lead in water as the sole source of environmental lead were found.
Lead in other sources. Other sources of lead include cosmetics (such as kohl), folk remedies, pottery, cans with lead-soldered seams, contaminated vitamins, and herbal remedies. In communities in which lead smelters or other industrial applications of lead exist, special attention should be paid to contaminated air, water, and workers’ clothing. Anyone who works with lead should change clothing and shoes and shower before leaving work. Lead soldiers, hand-made munitions, and other hobbies can be a source of lead. Vinyl mini blinds were identified as a source of lead and removed from the market in 1996. (See Appendix 1)
Lead Poisoning, or, “there are no safe levels of lead.”
Critical periods in human development.11 The developing embryo, fetus, and child are growing and changing rapidly. If, during this rapid period of change, the fetus or child is exposed to a poison of some kind, development can be deranged. These “critical windows of exposure” are specific periods of development during which the embryo or fetus is undergoing some process, such as the development of arms and legs between days 22-36 of pregnancy, when thalidomide damages their development.12, 13 There are many other examples of this effect, including tobacco smoke and behavioral effects, and alcohol and fetal alcohol syndrome. The critical period associated with harm from lead poisoning is brain and nervous system development, which begins in early pregnancy and continues until at least age 3 years. Since different parts of the nervous system are responsible for different functions, and since these different nervous system parts develop at different times, the timing of lead exposure can lead to different effects.14
Differences between children and adults. Children’s behaviors expose them to more lead dust through hand-to-mouth exploration, greater exposure to potentially lead-laden soil, and closer contact with lead dust and paint chips on the floor. Children also absorb lead more efficiently than adults through their digestive systems: children absorb 40-50% of ingested lead while adults only absorb 10-15%.15 In addition to greater absorption of lead from the digestive tract, the bones of infants and children are absorbing calcium at a high rate as they grow. Lead is chemically similar enough to calcium that it can be stored in bone, to be released gradually into the blood stream, providing an “internal source” of lead poisoning.16 There is similar evidence that lead and iron can occupy the same molecular sites, contributing to anemia and providing another “internal source” of lead. Another significant difference between children and adults is in the rate of their metabolisms. Children have significantly faster metabolisms, which means that they breathe faster and ingest proportionately more food and water.16 This difference means that in similar environments, children are exposed to a greater extent to contaminants. For example, the average infant drinks 5 oz of breast milk or formula per kilogram of body weight, an amount approximately equivalent to 20 liters of fluid for an adult. If formula is reconstituted using lead-contaminated tap water, that infant will receive a significant dose of lead. Similarly, breast milk can be contaminated with lead if the mother’s primary source of water is lead-contaminated.
The disease of lead poisoning is also different in children than in adults. (See Figure 1.) In adults, many of the effects are reversible, such as peripheral neuropathies (a loss of sensation or increased sensitivity in the arms or legs); in children, effects persist throughout their life, even after chelation (the drug treatment for severe lead poisoning). Because of these differences, our understanding of lead poisoning in adults cannot be extrapolated to children.
Lead’s effects on children. The effects of lead poisoning differ depending on many factors: dose, acuity or chronicity of poisoning, gender, age, nutritional status, the presence or absence of an enriching environment, developmental assets and supports, other toxicants in the body, and genetics. Lead levels typically peak around age 2 years, when normally developing children undergo a major change in dendrite connections. This time-related association between peak lead levels and major brain development leads to the theory that lead interferes with this critical process.
When studied in the laboratory, lead has been shown to alter basic nervous system functions, such as calcium modulated signaling, even at very low concentrations. Other effects of lead include interference with the synthesis of heme molecules (the oxygen-carrying molecules in red blood cells), leading to anemia, which has also been shown to affect intelligence. One study of lead levels in African American and Mexican American girls suggests that environmental exposure to very small amounts of lead (3 mcg/dl) can delay growth and puberty.17 This study contributes to the growing literature on environmental toxins and effects on human endocrine (hormonal) systems. Lead has also been shown to damage kidneys.18
The effects of lead poisoning on neurocognitive skills have been identified since at least 1966. Canfield19 showed that at even very low blood lead levels, children’s IQ scores were negatively affected. This study also showed that the effects on IQ were proportionately greater at lower levels than at higher levels. (See Figure 2.)
Figure 2. IQ as a Function of Lifetime Average Blood Lead Concentration.19
A 4-5 point decrease in IQ can mean the difference between normal and sub-normal intelligence and the ability to function independently; over the long term, it can mean a significant decline in the average intelligence of the affected population. Many other studies have demonstrated similar effects of blood lead levels under 10 mcg/dl; some have shown effects under 5 mcg/dl.20
Behavior and psychosocial effects. In addition to effects on IQ, distractibility, decreased reaction time,21 poor organizational skills, hyperactivity (including ADHD, or Attention Deficit Hyperactivity Disorder), and poor classroom performance22, 23 have been linked to lead poisoning. These effects have been recognized since at least 1976.24 The Port Pirie Cohort Study, a prospective study of the association of lifetime lead levels and emotional, behavioral, and cognitive effects, repeatedly showed significant, permanent, declines in cognition, behavior problems, and emotional problems that persisted throughout childhood to at least age 11-13 years.25
Long-term effects. Chronic exposure to lead has been linked to cerebrovascular and kidney disease, more often seen in adults. Lead has been linked to cancers in persons with lifetime lead exposures above 15 ppb in water.10
At higher levels.11 Fortunately, clinical lead toxicity, meaning patients that present with symptoms of lead poisoning such as headaches, abdominal pain, loss of appetite, constipation, clumsiness, agitation, decreased activity, or somnolence is increasingly rare. These symptoms indicate central nervous system involvement that can rapidly proceed to vomiting, stupor, convulsions, encephalopathy, and death. These symptoms typically present in children with blood lead levels higher than 60 mcg/dl. Anyone with these symptoms should be treated for a life-threatening emergency.
Lead in Pregnant Women and Nursing Mothers.
Because lead is chemically similar to calcium, it is incorporated into bone, which can result in a significant accumulation of lead in bones. If, during pregnancy and breastfeeding, maternal intake of calcium is not sufficient, these stores of lead and calcium are mobilized to supply calcium to the growing fetus and produce human milk.26, 27 Lead in maternal blood easily crosses the placenta,28 resulting in lead exposure of the fetus, and is readily incorporated into breast milk, leading to lead-contaminated breast milk.29, 30 The long-term effects of these exposures are difficult to quantitate in an environment in which many other sources of lead exist. However, one study of breastfed infants linked maternal lead stores to decreased weight gain in the first month of life,30 and a second concluded that the primary source of lead in infants under age 6 months is dietary, including breast milk and formula.31 These studies are particularly relevant to the situation in the District of Columbia. At very high levels of maternal lead, pregnancy loss has been reported.12
Treatment of Lead Poisoning.
The treatment of lead poisoning in children has been described in the CDC’s document “Managing Elevated Blood Lead Levels Among Young Children.”32 Unfortunately, no treatment for lead poisoning in children has been shown to reverse the long-term neurocognitive and behavioral effects,33 and the primary treatment for significant lead poisoning, chelation with succimer, has been implicated as causing a small decrease in IQ.34 Many studies have shown persistent cognitive and behavioral effects long after blood lead levels have dropped to levels considered “low”.25, 35, 36 Prevention of lead poisoning is the only solution to this disease.
Comparing the Risk of Lead Poisoning to Other Child Health Risks.
The CDC estimated that in 2000, there were 454,000 children in the US with blood lead concentrations higher than 10 mcg/dl. Depending on the quality of these children’s environments, we can estimate that each of these children lost at least 4-5 IQ points, and a significant proportion suffer from hyperactivity, behavioral and learning difficulties, and other long-term effects of lead poisoning. Comparing these losses to other child health risks is difficult, for there is no way to measure or place a value on how a person’s life would be if they had not been exposed. In terms of the overall health of children in the District of Columbia, the following comparisons can be made:
Preventable Condition Year of Estimate Percent of DC Children Affected Blood lead level greater than or equal to 10 mcg/dl 2002 3.8% of children tested at Children’s hospital; average level 3 mcg/dl37 Exposure to environmental tobacco smoke 2002 46%38 (compared to 38% nationwide)39 Children living in poverty 2003 29% (compared to 17% nationwide)40 Children without health insurance 2003 12% (compared to 12% nationwide)40 Children living in the Spring Valley/ American University area whose hair had higher levels of arsenic than the general population 2002 zero41
While these figures seem reassuring at first look, with “only” 3.8% of District children having a lead level 10 mcg/dl or higher, the reader should remember that even at values of 5 mcg/dl or lower neurocognitive and behavioral effects have been documented. Many of the children whose lead levels are 10 mcg/dl or higher are the same children living in poverty, exposed to environmental tobacco smoke, and/or without health insurance. These conditions add to the effects of lead poisoning; for poverty reduces educational opportunities, environmental tobacco smoke exposure has adverse effects on health, intelligence, and behavior, and lack of health insurance reduces access to the health care that might assist families in reducing lead poisoning and other harmful environmental exposures.
Comparative Risk by Source of Lead.
Since the banning of leaded fuel, lead paint has become the primary source of lead poisoning in the United States. While lead in water has been described, the proportion of lead ingested via water versus lead dust and other sources from lead paint has not been determined. Unfortunately, lead pipes are found in the same older homes in which lead paint is found, making it extremely difficult to separate the contribution of each source. Since there is no level of lead considered to be without negative effect, and since the population most at risk from lead poisoning is the same population that suffers from poor nutrition, inadequate schools, lack of developmental enrichment, and other consequences of poverty, our responsibility is to remove any and all sources of lead poisoning from these children’s environments. The harms of lead have been known for thousands of years; with many missed opportunities to remove lead from the environment due to cost concerns. There is no way to place a dollar value on the harm from lead poisoning to children in this city, as well as to children throughout the US and the world, no matter what source, water or paint.
Testing for Lead.
The standard procedure in most laboratories for testing lead in body fluids is the electrothermal atomization atomic absorption spectrophotometry assay. This method replaces less sensitive methods such as the free erythrocyte protoporphyrin, erythrocyte porphyrin, or zinc protoporphyrin tests.32 There are newer products on the market for testing lead levels in body fluids at this time; the sensitivity, specificity, and validity of these methods have not yet been completely determined, particularly at low levels of lead. Testing of hair, fingernails, and teeth should not be done because they are subject of external contamination, making test results uninterpretable.32 On occasion, an abdominal radiograph (“X-ray”) is useful for determining if a child has a significant amount of chipped paint in his or her digestive tract. If present, the paint chips can be removed. Radiographs of bones looking for “lead lines” are not useful.32 A new technique, K X-ray fluorescence, is entering the field of lead research. This instrument measures long-term lead deposits as densities in bone, similar to measurements of bone density for the diagnosis of osteoporosis.42 There are consumer test kits for lead in paint,43 and many professional lead testing services exist. Reliability of test results varies considerably, so consumers should follow guidelines such as those from the Consumer Product Safety Commission in testing for lead, selection of a method of abatement if lead paint exists, and careful abatement procedures. See Appendix B.
Research and Lead in District of Columbia Water.
On March 30, 2004, the Centers for Disease Control and Prevention published a report on blood lead levels in residents of homes with elevated lead in tap water in the District of Columbia. This study indicated that a long-term decline in the blood lead levels of children living in homes with lead service lines had halted in 2000, the year chloramines were added to water in the District of Columbia. While there are several limitations to this study, primarily due to the speed with which it was performed, the results are disturbing. The CDC recommends that public health interventions focus on eliminating lead exposures in children, and that lead concentrations in drinking water be below the EPA action level of 15 ppb.44
Children’s has begun an analysis of the last 10 years of lead test results performed in our laboratory. We will look at the average lead level during the 10 year period, noting any changes in the average. We will also look for associations between lead levels in the children tested and lead levels in household water supply, the presence of lead paint in the home, insurance status, and other potential influences. This study is an extremely high priority; we will inform Congress and the District of Columbia of our results as soon as they are available.
The children of the District of Columbia deserve a safe environment in which to grow and develop into adults contributing to DC’s future. The effect of lead poisoning, even at levels not yet considered to be “poisonous,” is to reduce the potential of yet another generation of children. There is no way to place a value on this loss of potential; however, we do know that the loss of IQ points and changes in behavior are measurable and significant. We also know that the resources available to many of the District’s children are fragmented, in some instances non-existent, and rarely adequate to the challenges presented by poverty, race and ethnicity, and violence found in this city. This combination sentences the District’s children to yet another generation of poverty and poor health. The law says lead levels higher than 15 ppb need to be abated. The children deserve this.
Thank you for this opportunity to inform you about lead and children, pregnant women and breastfeeding women. I am available for questions today or in the future.
NEWS from U.S. Consumer Product Safety Commission Office of Information and Public Affairs, Washington, DC 20207 June 25, 1996, Release # 96-150
CPSC Finds Lead Poisoning Hazard for Young Children in Imported Vinyl Miniblinds
WASHINGTON, D.C. After testing and analyzing imported vinyl miniblinds, the U.S. Consumer Product Safety Commission (CPSC) has determined that some of these blinds can present a lead poisoning hazard for young children. Twenty-five million non-glossy, vinyl miniblinds that have lead added to stabilize the plastic in the blinds are imported each year from China, Taiwan, Mexico, and Indonesia.
CPSC found that over time the plastic deteriorates from exposure to sunlight and heat to form lead dust on the surface of the blind. The amount of lead dust that formed from the deterioration varied from blind to blind.
In homes where children ages 6 and younger may be present, CPSC recommends that consumers remove these vinyl miniblinds. Young children can ingest lead by wiping their hands on the blinds and then putting their hands in their mouths. Adults and families with older children generally are not at risk because they are not likely to ingest lead dust from the blinds. Lead poisoning in children is associated with behavioral problems, learning disabilities, hearing problems, and growth retardation. CPSC found that in some blinds, the levels of lead in the dust was so high that a child ingesting dust from less than one square inch of blind a day for about 15 to 30 days could result in blood levels at or above the 10 microgram per deciliter amount CPSC considers dangerous for young children.
"Some of the vinyl blinds had a level of lead in the dust that would not be considered a health hazard, while others had very high levels," said CPSC Chairman Ann Brown. "Since consumers cannot determine the amount of lead in the dust on their blinds, parents with young children should remove these vinyl miniblinds from their homes."
CPSC asked the Window Covering Safety Council, which represents the industry, to immediately change the way it produces vinyl miniblinds by removing the lead added to stabilize the plastic in these blinds. Manufacturers have made the change and new miniblinds without added lead should appear on store shelves beginning around July 1 and should be widely available over the next 90 days.
Stores will sell the new vinyl blinds packaged in cartons indicating that the blinds are made without added lead. The cartons may have labeling such as "new formulation," "nonleaded formula," "no lead added," or "new! non-leaded vinyl formulation." New blinds without lead should sell in the same price range as the old blinds at about $5 to $10 each. CPSC recommends that consumers with young children remove old vinyl miniblinds from their homes and replace them with new miniblinds made without added lead or with alternative window coverings. Washing the blinds does not prevent the vinyl blinds from deteriorating, which produces lead dust on the surface.
The Arizona and North Carolina Departments of Health first alerted CPSC to the problem of lead in vinyl miniblinds. CPSC tested the imported vinyl miniblinds for lead at its laboratory. The laboratories of NASA's Goddard Space Flight Center and the Army's Aberdeen Test Center used electron microscope technology to confirm that as the plastic in the blinds deteriorated, dust formed on the surface of the blind slats. This testing also established that the dust came from the blinds and not from another source. CPSC laboratory tests confirmed that this dust contained lead.
"This lead poisoning is mainly a hazard for children ages 6 and younger," said Chairman Brown. "Adults and older children generally are not at risk because they are not likely to ingest lead dust from the blinds."
Consumer Product Safety Commission What You Should Know About Lead Based Paint in Your Home: Safety Alert CPSC Document #5054
Lead-based paint is hazardous to your health. Lead-based paint is a major source of lead poisoning for children and can also affect adults. In children, lead poisoning can cause irreversible brain damage and can impair mental functioning. It can retard mental and physical development and reduce attention span. It can also retard fetal development even at extremely low levels of lead. In adults, it can cause irritability, poor muscle coordination, and nerve damage to the sense organs and nerves controlling the body. Lead poisoning may also cause problems with reproduction (such as a decreased sperm count). It may also increase blood pressure. Thus, young children, fetuses, infants, and adults with high blood pressure are the most vulnerable to the effects of lead.
Children should be screened for lead poisoning. In communities where the houses are old and deteriorating, take advantage of available screening programs offered by local health departments and have children checked regularly to see if they are suffering from lead poisoning. Because the early symptoms of lead poisoning are easy to confuse with other illnesses, it is difficult to diagnose lead poisoning without medical testing. Early symptoms may include persistent tiredness, irritability, loss of appetite, stomach discomfort, reduced attention span, insomnia, and constipation. Failure to treat children in the early stages can cause long-term or permanent health damage. The current blood lead level which defines lead poisoning is 10 micrograms of lead per deciliter of blood. However, since poisoning may occur at lower levels than previously thought, various federal agencies are considering whether this level should be lowered further so that lead poisoning prevention programs will have the latest information on testing children for lead poisoning.
Consumers can be exposed to lead from paint. Eating paint chips is one way young children are exposed to lead. It is not the most common way that consumers, in general, are exposed to lead. Ingesting and inhaling lead dust that is created as lead-based paint "chalks," chips, or peels from deteriorated surfaces can expose consumers to lead. Walking on small paint chips found on the floor, or opening and closing a painted frame window, can also create lead dust. Other sources of lead include deposits that may be present in homes after years of use of leaded gasoline and from industrial sources like smelting. Consumers can also generate lead dust by sanding lead-based paint or by scraping or heating lead-based paint. Lead dust can settle on floors, walls, and furniture. Under these conditions, children can ingest lead dust from hand-to-mouth con- tact or in food. Settled lead dust can re-enter the air through cleaning, such as sweeping or vacuuming, or by movement of people throughout the house.
Older homes may contain lead based paint. Lead was used as a pigment and drying agent in "alkyd" oil based paint. "Latex" water based paints generally have not contained lead. About two-thirds of the homes built before 1940 and one-half of the homes built from 1940 to 1960 contain heavily-leaded paint. Some homes built after 1960 also contain heavily-leaded paint. It may be on any interior or exterior surface, particularly on woodwork, doors, and windows. In 1978, the U.S. Consumer Product Safety Commission lowered the legal maximum lead content in most kinds of paint to 0.06% (a trace amount). Consider having the paint in homes constructed before the 1980s tested for lead before renovating or if the paint or underlying surface is deteriorating. This is particularly important if infants, children, or pregnant women are present.
Consumers can have paint tested for lead. There are do-it-yourself kits available. However, the U.S. Consumer Product Safety Commission has not evaluated any of these kits. One home test kit uses sodium sulfide solution. This procedure requires you to place a drop of sodium sulfide solution on a paint chip. The paint chip slowly turns darker if lead is present. There are problems with this test, however. Other metals may cause false positive results, and resins in the paint may prevent the sulfide from causing the paint chip to change color. Thus, the presence of lead may not be correctly indicated. In addition the darkening may be detected only on very light-colored paint. Another in-home test requires a trained professional who can operate the equipment safely. This test uses X-ray fluorescence to determine if the paint contains lead. Although the test can be done in your home, it should be done only by professionals trained by the equipment manufacturer or who have passed a state or local government training course, since the equipment contains radioactive materials. In addition, in some tests, the method has not been reliable.
Consumers may choose to have a testing laboratory test a paint sample for lead. Lab testing is considered more reliable than other methods. Lab tests may cost from $20 to $50 per sample. To have the lab test for lead paint, consumers may:
· Get sample containers from the lab or use re-sealable plastic bags. Label the containers or bags with the consumer's name and the location in the house from which each paint sample was taken. Several samples should be taken from each affected room (see HUD Guidelines discussed below).
· Use a sharp knife to cut through the edges of the sample paint. The lab should tell you the size of the sample needed. It will probably be about 2 inches by 2 inches.
· Lift off the paint with a clean putty knife and put it into the container. Be sure to take a sample of all layers of paint, since only the lower layers may contain lead. Do not include any of the underlying wood, plaster, metal, and brick.
· Wipe the surface and any paint dust with a wet cloth or paper towel and discard the cloth or towel.
The U.S. Department of Housing and Urban Development (HUD) recommends that action to reduce exposure should be taken when the lead in paint is greater than 0.5% by lab testing or greater than 1.0 milligrams per square centimeter by X-ray fluorescence. Action is especially important when paint is deteriorating or when infants, children, or pregnant women are present. Consumers can reduce exposure to lead-based paint.
If you have lead-based paint, you should take steps to reduce your exposure to lead. You can:
· Have the painted item replaced. You can replace a door or other easily removed item if you can do it without creating lead dust. Items that are difficult to remove should be replaced by professionals who will control and contain lead dust.
· Cover the lead-based paint. You can spray the surface with a sealant or cover it with gypsum wallboard. However, painting over lead-based paint with non-lead paint is not a long-term solution. Even though the lead-based paint may be covered by non-lead paint, the lead-based paint may continue to loosen from the surface below and create lead dust. The new paint may also partially mix with the lead-based paint, and lead dust will be released when the new paint begins to deteriorate.
· Have the lead-based paint removed. Have professionals trained in removing lead-based paint do this work. Each of the paint-removal methods (sandpaper, scrapers, chemicals, sandblasters, and torches or heat guns) can produce lead fumes or dust. Fumes or dust can become airborne and be inhaled or ingested. Wet methods help reduce the amount of lead dust. Removing moldings, trim, window sills, and other painted surfaces for professional paint stripping outside the home may also create dust. Be sure the professionals contain the lead dust. Wet-wipe all surfaces to remove any dust or paint chips. Wet-clean the area before re-entry.
· You can remove a small amount of lead-based paint if you can avoid creating any dust. Make sure the surface is less than about one square foot (such as a window sill). Any job larger than about one square foot should be done by professionals. Make sure you can use a wet method (such as a liquid paint stripper).
· 4. Reduce lead dust exposure. You can periodically wet mop and wipe surfaces and floors with a high phosphorous (at least 5%) cleaning solution. Wear waterproof gloves to prevent skin irritation. Avoid activities that will disturb or damage lead based paint and create dust. This is a preventive measure and is not an alternative to replacement or removal.
· Professionals are available to remove, replace, or cover lead-based paint.
· Contact your state and local health departments lead poisoning prevention programs and housing authorities for information about testing labs and contractors who can safely remove lead-based paint.
· The U.S. Department of Housing and Urban Development (HUD) prepared guidelines for removing lead-based paint which were published in the Federal Register, April 18, 1990, page 1455614614. Ask contractors about their qualifications, experience removing lead-based paint, and plans to follow these guidelines.
· Consumers should keep children and other occupants (especially infants, pregnant women, and adults with high blood pressure) out of the work area until the job is completed.
· Consumers should remove all food and eating utensils from the work area.
· Contractors should remove all furniture, carpets, and drapes and seal the work area from the rest of the house. The contractor also should cover and seal the floor unless lead paint is to be removed from the floor.
· Contractors should assure that workers wear respirators designed to avoid inhaling lead.
· Contractors should not allow eating or drinking in the work area. Contractors should cover and seal all cabinets and food contact surfaces.
· Contractors should dispose of clothing worn in the room after working. Workers should not wear work clothing in other areas of the house. The contractor should launder work clothes separately.
· Contractors should clean up debris using special vacuum cleaners with HEPA (high efficiency particulate air) filters and should use a wet mop after vacuuming.
· Contractors should dispose of lead-based paint waste and contaminated materials in accordance with state and local regulations.
Government officials and health professionals continue to develop advice about removing lead-based paint. Watch for future publications by government agencies, health departments, and other groups concerned with lead-paint removal and prevention of lead poisoning.
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