Lead and its human effects
Lead is a useful and common metal that has been used by humans for thousands of years. It is also a very dangerous poison, particularly for children, when it is accidentally inhaled or ingested.
Rules and regulations prohibit lead in common products like most gasoline and paint, so lead poisoning has dramatically declined in the United States. However, it is still a real problem that continues to poison thousands of people in the U.S. each year. The following will provide information about sources of lead in the environment, who is most at risk for lead poisoning, how you can reduce the chances that you or your children will become injured by lead, and what Public Health - Seattle & King County is doing about the lead problem.
||Health effects - there is no safe level
||Though lead is found frequently in our environment, it has no known purpose in our bodies. When lead gets inside the body, the body confuses it with calcium and other essential nutrients. This confusion can cause permanent damage to the health of both children and adults.
"Lead is a developmental toxicant" and the "harmful effects of lead on children's development can occur without signs or symptoms."
~ Centers for Disease Control and Prevention
In children, lead is most damaging when they are six years and younger. Children are growing at a very fast rate - growing bones, developing stronger muscles and creating many connections in their brain. When lead instead of essential nutrients is "available" to the body to make bones, muscle, and brain connections, permanent harm to health can occur. Even at low levels, lead can be harmful and be associated with:
- Learning disabilities resulting in a decreased intelligence (decreased IQ)
- Attention deficit disorder
- Behavior issues
- Nervous system damage
- Speech and language impairment
- Decreased muscle growth
- Decreased bone growth
- Kidney damage
High levels of lead are life threatening and can cause seizures, unconsciousness, and death.
Lead exposure is a concern for adults, even though they have finished growing. Since an adult's body is much larger than a child's body, more lead is needed to cause injury but the harm lead can do to an adult is very serious. High levels of lead can cause:
- Increased chance of illness during pregnancy
- Harm to a fetus, including brain damage or death
- Fertility problems in both men and women
- High blood pressure
- Digestive issues
- Nerve disorders
- Memory and concentration problems
- Muscle and joint pain
||Who's most at risk for getting hurt by lead?
Children are most at risk for lead injuries because their bodies are still developing and because they tend to put things that may have lead dust on it in their mouths. Here's more:
Children are still developing:
Until about age 6, young children do not have a fully developed "blood brain barrier." The blood brain barrier is the body's way of keeping harmful chemicals out of the brain, but it is not fully formed at birth and takes up to about six years to be fully protective. Without the blood brain barrier, the effects of lead are even more devastating. For more information about the blood brain barrier, see the resource links below.
Putting things in the mouth:
Children, particularly young children, explore their world by touching and tasting everything they can get their hands on. It's a natural part of their development. Children also spend more time on the floor, outside in the dirt, and playing and exploring. So, if there is lead dust or dirt with lead in it in the environment, children will get it on their hands and fingers and into their mouths. And since children are short, they breathe near the floor and ground, closer to dirt and dust that may have lead in it.
People with pica
While it is normal for children under 2 to explore by putting everything in their mouth, there is a condition in older children and adults called pica. This is a condition where a person craves and eats non-food substances, including soil or dirt. Children under two eat non-food because they are exploring their world. However, when people over two years old do it and the craving lasts for at least a month or so, it is a condition is called "pica." Read a report on a meeting with scientists who study Pica.
Newcomers and refugees
The United States banned lead in most paint and in gasoline by the mid-1980s, which dramatically reduced the amount of lead in the environment. Other countries, however, may still allow lead in these common products. It is very important that new arrivals, particularly children from Africa, the Middle East, and Asia, be tested for the presence of lead in their blood. If the levels are extremely high they may need chelation. Chelation is a process for removing lead from the body.
There are many sources of lead in our environment. Here are a few of the most common:
- Lead paint:
The most common source is lead paint. Lead carbonate [PbCO3/Pb(OH)2)] was added to paint to speed drying, improve durability, and protect the surface from corrosion. Even though the negative health impacts of leaded paint were known as far back as the early 1900s, lead in residential paint was not banned until 1978. If a building was built before 1978 and has older paint, it should be assumed to have lead paint.
Children are at particular risk from lead paint because they occasionally eat paint chips (sometimes on purpose). Lead paint can have a sweet taste, and babies and toddlers will often lick or suck windowsills, crib bars, and other objects that may be coated with lead paint. Leaded dust from peeling, chipping, cracking or otherwise deteriorating lead paint will collect onto floors and other surfaces. Children touch the dust, and then put their fingers in their mouths.
Lead paint will only harm you or your family if it is peeling, flaking, or otherwise coming off of the surface.
Leaded dust from paint can be a big problem during remodeling, when lead dust can become a hazard for the whole family, but particularly children. There are many tips for safe remodeling, which guide the use of sanders, scrapers, heat guns, keeping children and pets out of work areas, and how to clean up afterwards. Visit the Environmental Protection Agency (EPA) for more information.
- Imported candies:
Lead has been found in candy and candy wrappers imported primarily from Mexico and Asia. Learn how the United States Food and Drug Administration (FDA) is trying to control lead in imported candies
- Hobbies and art:
Some art supplies, such as artists' paint, still have lead in them. Buy only non-toxic paints for your children. Some hobbies require the use of lead, such as stained glass, firing guns, making ammunition, and making fishing lures and sinkers. Keep children away from areas where lead is being used. Be sure not to bring lead dust on your clothing into the home.
- Contaminated soil:
Another common source of lead. Two possible sources of contaminated soil are leaded gasoline and industrial operations like smelters. While gasoline is generally no longer a major source of lead, decades of leaded gasoline left contamination in the soil next to roadways up to one-quarter of a mile from the road.
While gasoline is generally no longer a major source of lead, decades of leaded gasoline left contamination in the soil next to roadways up to one-quarter of a mile from the road.
Historic smelter operations, such as the ASARCO copper smelter that operated near Tacoma for almost 100 years, may also have contaminated the soil. ASARCO's "Tacoma Smelter Plume" pollution was carried by the wind throughout the Puget Sound, leaving elevated levels of lead and arsenic in the soil in some parts of King County.
People and pets track the contaminated dirt into their homes. Children play on or near the floor, getting their hands dirty, and then put their fingers in their mouths. To learn how to reduce exposure to contaminated soil, read the Guidelines to reduce exposure to contaminated soils on the Tacoma Smelter Plume website.
Some jewelry is made of lead and can pose a danger to children if they put the jewelry in their mouths. Lead is not absorbed through the skin. Teach children to keep jewelry out of their mouths, or do not allow children to have lead jewelry. Learn more from the Centers of Disease Control and Prevention (CDC).
- Lead at work:
Adults who work in industries that use lead (battery manufacturing, pipe fitting, firing ranges, demolition, glass production, smelting operations, etc.) should be careful not to bring lead home with them. Shower and change clothes and shoes at work. Do not contaminate your car.
Imported glazed pottery and leaded crystal may also be sources of lead. Minimize the use of these products.
- Drinking water:
Drinking water may have lead in it, though permitted levels in municipal sources are carefully regulated. The largest source of lead in drinking water occurs through leaching from lead-containing pipes, faucets, and solder, which can be found in plumbing of older buildings. If you have older pipes in your home, be sure to run the water for 60 seconds every morning before using it. Do not use hot tap water for drinking purposes. Learn more about drinking water from the EPA or visit the Seattle Public Utilities website
In 2004 some schools in the Seattle School District were found to have lead in the drinking water. Learn more about what the school district found.
Vinyl mini-blinds imported from China, Indonesia, Taiwan and Mexico before 1997 contained lead, which was used to make them less brittle. Lead dust forms on the blinds, particularly when the blinds are exposed to sun and heat. According to the U.S. Consumer Product Safety Commission, different blinds contained different amounts of lead. While the blinds are no longer imported into the United States, older blinds containing lead may still be in use or available for purchase in thrift shops. Learn more about this topic.
- Lunch boxes:
There is evidence that some soft vinyl lunch boxes may contain lead in the lining. The Center for Environmental Health claims that there is a real risk to children. However, the Consumer Products Safety Commission does not believe the amounts of lead present pose a serious risk to children. Learn more from the Center for Environmental Health and the Consumer Products Safety Commission.
||Begin reducing your risk today
There are many steps you can take right now to reduce you and your family's risk of exposure from lead.
Blood lead testing:
The only way to know if your child is lead-poisoned is by getting him or her a blood lead test. If your child has Medicaid insurance, testing for blood lead levels is required, especially for children at 12 months and 24 months of age. Children with Medicaid insurance between the ages of 36 months and 72 months of age must receive a lead screening blood test if they have not been previously tested.
Talk with your child's physician.
To do the test your physician will need to obtain some of your child's blood. The blood can be drawn in two ways - 1) from a vein in the arm or 2) a prick on the finger or heel. If blood is drawn from a prick on the finger or heel and the results are high, your child should be re-tested using the blood collected from the arm to confirm the results. Blood collected from the vein provides the surest results.
If your child has a high blood lead level, some follow up may be necessary. For example, you may be eligible for a visit from Public Health experts who can investigate potential sources of lead in your home that may be contributing to your child's lead level.
Check your house for lead hazards:
Conduct routine check of your house looking for lead hazards. One way to do so is by contacting a professional. A professional can check your home in one of two ways, or both:
- A paint inspection tells you the lead content of every different type of painted surface in your home. It won't tell you whether the paint is a hazard or how you should deal with it.
- A risk assessment tells you if there are any sources of significant lead exposurecsuch as peeling paint and lead dust) that will impact your family's health. It also tells you what actions to take to address these hazards.
- Washington State Certified Lead-Based Paint Firms (PDF)
Reduce the dust levels in your home:
- Use a door mat to remove dirt from shoes before taking them off. Clean dust from underneath the matt frequently.
- Take off your shoes before going into your home. Even after scraping off dirt, shoes will track some dust and lead into your home.
- Keep play areas clean. Frequently wash toys, pacifiers, stuffed animals and other objects young children put in their mouths.
- Damp dust and damp mop the house at least once a week. Damp mopping and damp dusting are very effective at picking up dust.
- Keep your sidewalks and porch free of dust and debris. Use a HEPA vacuum if possible but a broom can work as well.
- Wash your hand before every meal and snack.
- Keep children from eating and chewing on non-food items such as paint chips, window sills, and dirt.
- Avoid using imported glazed pottery for food.
- Eat foods high in calcium, Vitamin C and iron. Good nutrition helps prevent the body from absorbing lead.
- If you enjoy candies imported from Mexico, check the list of candies that have been shown to contain lead, and avoid those candies.
Have qualified professionals do remodeling work such as re-painting. There are standards that professionals must meet to ensure work with leaded paint is done safely, reliably, and effectively. Contact the Washington State Department of Community Trade and Economic Development for a list of contacts in your area.
If you know you have leaded soil or leaded paint take interim steps while you are figuring out a long-term solution. For example, temporarily reduce lead paint hazards by repairing damaged painted surfaces. To minimize exposure to contaminated soil, plant grass or use bark to cover soil. These actions are not permanent solutions and will need ongoing attention.
||Public Health - Seattle & King County's Environmental Health Division has been raising awareness about childhood lead poisoning. Below you will find brief descriptions of several programs currently focusing in on childhood blood lead poisoning prevention.
- EPA grant:
Lead poisoning is the number one pediatric environmental health issue nationally, but in King County and Washington State as a whole there has been a tradition and entrenched belief that lead is "not a problem" in our area. Consequently, little blood lead testing or education occurs here in our county. Public Health's Environmental Health Division received a grant in 2005 from the Environmental Protection Agency to find ways to increase the amount of blood lead screening doctors provide for children living in King County and to launch a formal lead poisoning awareness campaign.
- Environmental risk investigations:
If your child has received a blood lead test and the results exceed the Centers for Disease Control & Prevention "action limit" (10 micrograms per deciliter) your family is eligible to have a free visit from a Public Health - Seattle & King County staff member to look for potential sources of lead present in your home that may be contributing to your child's lead level. The investigation will typically have five parts to it.
||A set of questions focusing in on housing, behavior of the child(ren), family lifestyle and travel will be asked. These questions are designed to help narrow down the list of potential sources of lead to those relating specifically to your family. After potential sources of lead have been identified a more in-depth look at those sources can take place.
||To further examine potential sources of lead in your house a thorough walk-through will be done. The walk-through occurs inside and outside the house. Key items that will be looked at include paint condition, surfaces and moisture barriers.
||(optional): Samples may be collected to further identify or confirm suspected sources of lead present in the house. Types of samples that may be collected include paint chips, dust wipes, soil, and/or water. Any samples that are obtained will be submitted to a laboratory for analysis.
||Once all of the information has been collected and analyzed, a plan of action will be developed. A plan of action will include a letter summarizing the investigation and a checklist of recommended activities or actions to reduce your child's exposure to lead. Your child will be advised to get additional blood lead test(s) until his/her level of lead is below the Centers for Disease Control & Prevention action limit. This plan of action will be mailed to you and the child's medical care provider.
||Periodically, the Public Health investigator will check in with you to see how things are going and answer any questions that may have come up. We will continue to provide this service until your child's blood lead level has fallen below the Centers for Disease Control & Prevention action limit.
- Tacoma Smelter Plume:
The Tacoma Smelter Plume project is an effort by Public Health - Seattle & King County, state agencies and local communities to investigate and raise awareness about the soil contamination from the ASARCO copper smelter. Lead and arsenic came from the smelter's smokestacks located in Ruston, near Tacoma, and were carried by wind throughout central Puget Sound. The smelter, which operated for almost 100 years, polluted the soil in parts of King County.
Results from the studies show that low to moderate levels of arsenic and lead soil contamination is present in some soil throughout King County. Currently, licensed childcare facilities in the areas most contaminated are being offered an opportunity to have their soils tested, receive educational information on how to reduce their exposure to contaminated soils, and access to curriculums geared toward teaching our children how to play safe around contaminated soil.
For additional information please call Environmental Health Services at 206-263-9566 and visit our website.
- Child Care Assessment Project:
The Local Hazardous Waste Management Program in King County (LHWMP) is assessing licensed childcare facilities for potential exposure(s) to hazardous wastes, including lead. Over the next year, several licensed child care facilities will have a limited lead risk assessment completed. The assessment will evaluate whether visual indicators of a lead hazard being present (facility built pre 1950, deteriorated exterior windows, lead paint chips on ground, etc.) are reliable tools for evaluating lead exposure risk in King County. This will be achieved by correlating visual indicators with data obtained through dust wipes analyzed for lead. Results from this assessment will be available in late 2007.
For additional information regarding this project please call our Environmental Health Services office at 206-263-9566.