While people have known for millennia that lead is a toxic substance, it wasn’t until the mid-1970s that scientists recognized exactly how dangerous it can be, even at low levels of exposure. Yet even now,a third of the world’s children—up to 800 million globally—are affected by lead poisoning.
Alexander van Geen, a Lamont-Doherty Earth Observatory research professor who studies environmental impacts on human health, was recently awarded a grantto study the use of a new test to address lead poisoning. Van Geen is working with colleagues Pam Factor-Litvak, professor of epidemiology at Columbia University’s Mailman School of Public Health, and Brendan O’Flaherty, professor of economics at Columbia. They will distribute these new lead-testing kits to pregnant women to determine if their homes contain lead paint, to better protect their young children and fetuses from lead poisoning. “The study is a combination of new chemistry and citizen science participation,” said van Geen.
No amount of lead exposure is safe for children—even low levels of exposure can lead to lead poisoning, which can severely impact mental and physical development. Because the U.S. has no nationwide universal testing system to track children at risk of lead poisoning, it can be difficult for parents to know if their children have been exposed to lead. Children may have no symptoms until the lead buildup in their bodies has reacheddangerous levels. Blood testing, which measuresthe micrograms of lead per deciliter of blood,is the best way to determine if a child has been exposed to lead, yet it’s estimated that less than 20% of young children are being tested for lead.The CDC’s level of3.5 micrograms of lead per deciliter of blood is used to flag children at potential risk.
Van Geen’s study will focus on Vailsburg, a neighborhood in the western part of Newark, New Jersey, where many immigrants from West Africa and the West Indies, Haiti, Guyana, Jamaica, Ghana, Nigeria, Liberia and Ukraine now live. Vailsburg was chosen for the study, because a Reuters map of U.S. states showing levels of lead in the blood of children monitored between 2005 and 2015, revealed that Vailsburg’s levels were conspicuously high.
“During that decade, 20% of the kids were above the then-reference level of the CDC,” said van Geen. “And today, this Vailsburg zip code remains higher than any of the other zip codes. The most likely reasons at this point would be lead-based paint and pre-1978 housing, not enough testing going on, not enough awareness. And that’s what we hope to correct by distributing these kits through a local community organization.”
The dangers of lead
Children under the age of 6 are particularly vulnerable to lead. Babies and young children put everything into their mouths, which can include paint chips or lead-contaminated soil or water. Because their bodies are still growing, their nervous systems and brains are more sensitive to lead’s toxic effects, and irreversible brain damage is possible. The signs of lead poisoning include developmental delays, learning problems, irritability, hyperactivity, loss of appetite, weight loss, fatigue, headaches, abdominal pain, cramps, vomiting, constipation, hearing loss and seizures. Very high levels of lead can cause unconsciousness and even death.
Lead builds up in the body over time and is stored in bones with calcium. When a woman is pregnant, her bones release lead with calcium, which can expose her fetus to lead. Newborns who have been exposed to lead in the womb can be born prematurely and have lower birth weights and slower growth than children not exposed to lead. Moreover, pregnant women exposed to lead may miscarry or have a stillbirth.
Adults with lead poisoning might experience high blood pressure, joint pain, difficulty concentrating or remembering things, headaches, abdominal pain, mood disorders, reduced kidney function and reproductive problems. Some of the greatest artists who used lead paint, including Michelangelo, Caravaggio and Van Gogh, suffered from “painter’s madness” or “painter’s colic,” likely caused by lead exposure. Beethoven’s deafness and other illnesses were also likely connected to lead poisoning.
Where did all this lead come from?
Lead, a metal, occurs naturally in the earth, but mining, fossil fuel burning and other human activities have spread it around the environment. Humans began using lead in Ancient Rome, putting it in dishes, paints and pipes. The word “plumbing” comes from the Latin word for lead: “plumbum.”
In fact, exposure to lead is thought to have contributed to the fall of the Roman Empire. In the past, lead was favored because it was inexpensive, moldable, durable and washable. During the 19thcentury, lead was also found in wines, foods, medicines and ointments.
In the U.S., lead has commonly been used in paint and gasoline. Lead paint was widely used on homes during the 1950s because it was more durable than lead-free paint. Lead paint was also used on baby carriages, cribs and toys.It isstill used in batteries, pipes, roofing materials and in some pottery and cosmetics. Although signs of lead poisoning in children were noticed in the 1930s, the government did not ban lead paint in homes, toys and furniture until 1978. The lead paint, however, was never systematically removed from old buildings.
Environmental justice and lead
Between 2005 and 2015,the proportion of children under the age of 6 with blood lead levels above five micrograms per deciliter (CDC’s pre-2021 measurement to identify children potentially at risk for lead toxicity) living in older housing was 20 to 40% higher and sometimes 10 times higher than in wealthier neighborhoods nearby. Children in communities of color were exposed to lead at greater rates than those in other communities, according to data about children’s blood lead levels between 2005 and 2015, as gathered by Reuters investigative reporters.
A 2020 study found that in the U.S., Black children were exposed to lead at greater rates and had higher blood lead levels than did children in other communities, because one in four Black children nationwide live in pre-1950 homes, and one in six live in poverty. Another study determined that Black families segregated into separate, unequal neighborhoods with fewer resources had higher levels of lead in their blood, which ultimately had a negative impact on their children’s fourth-grade reading levels.
The study
Up to 500 test kits will be distributed by United Vailsburg Services Organization, the study’s community partner, focusing on households with pregnant women and young children. Van Geen hopes to begin the study this September.Participants will learn about the health risks of lead and be taught how to use the kits and record results on their cell phones. To test for lead, they will spray a reagent—a substance that causes a reaction in another substance—onto a sample of paint. This reagent converts lead into a fluorescent green perovskite, a mineral used in solar cells, which is visible under a UV light.
To confirm the accuracy of the kit’s findings, the results of the test will be compared to lead measurements done by a certified lead inspector using X-ray fluorescence, which can also detect the presence of lead.
The kit, called Lumetallix, was developed by an Amsterdam-based company. Van Geen has already used it in a pilot study in Abidjan on the Ivory Coast with a team of French scientists. That study—which employed local doctors to encourage the women to use the kits—found that only 25% of the women complied if the doctors were not around.
Vailsburg will work with the local community organization to see if that helps increase participation in the study. “We will make the kits available and we will train people,” said van Geen. The study will then examine data acquired from the city of Newark and the Department of Health, and compare levels of lead in blood from before and after the study to see if the self-testing kits had an impact. “We know that the average is a factor of two higher in Vailsburg than it is in neighboring zip code areas. After a one-year intervention for the newborn children and the one- and two-year-olds, we want to see whether that difference is going to diminish.”
What if lead is discovered?
The women recruited to be part of the study will be given a package which tells them what to do if lead is discovered in their homes. “Don’t let children play unattended and put things in their mouths in rooms that have lead-based paint, especially if it’s peeling paint,” said van Geen. “The other step is advising them to repaint. But most importantly, the city of Newark has funds. With this evidence, you can call them and ask them to come and do their own official inspections. Then they will give you advice on what to do. We’re hoping they’re going to get an uptick in demand from the intervention area.”
The city of Newark was awarded a $5.6 million Lead Hazard Reduction grant by HUD for homeowners and tenants to remediate lead paint. People living in housing built before 1978, pregnant women, households with children under 6 and families with an income 80% below the area’s average are eligible to apply for funds.
How lead is remediated
Lead abatement is regulated by the EPA. And anyone doing lead abatement must be certified.
There are four methods of abating lead:
Encapsulation: A paint-like coating is used to cover the lead and create a watertight bond. Eventually, however, the coating can weaken.
Enclosure: The lead surface is covered with drywall, or aluminum or vinyl siding.
Removal: The lead is removed by brushing or scraping with liquid paint removers. It can also be electrically sanded away using a high efficiency particulate air filtered vacuum.
Replacement: The lead surface is completely removed and replaced with a non-toxic material. This method, though the most expensive, is the most effective.
Lead laws
The Toxic Substances Control Act and the Residential Lead-Based Paint Hazard Reduction Act of 1992, administered by the EPA, regulate lead in paint, dust and soil. These regulations set standards for dangerous levels of lead in paint, dust and residential soil; mandate that buyers and renters of pre-1978 housing are informed about lead hazards; and require that those involved in renovation and repair, lead abatement and lead inspection be certified. In addition, 45 states have laws addressing lead hazards in homes.
How to avoid lead exposure
Although lead paint and lead in gasoline have been banned in the U.S., lead can still be found in soil, water from lead pipes and in certain toys and jewelry. Pewter, brass or leaded crystal serving containers may contain lead. Some candies, cosmetics, spices, glazed pots and foods from other countries also contain lead. Lead paint is still being sold in parts of Africa, South America and Asia.And the informal recycling of leaded batteries in some poor and middle-income countries also puts people at risk of lead poisoning.
Jobs such as construction or renovation, and hobbies like making stained glass or glazed pottery may also expose you to lead.
How to reduce your risk of lead exposure:
- Inspect and maintain painted surfaces in your home and wipe painted areas.
- Keep your home dust free.
- Deal with water damage as soon as possible.
- Use only cold water for cooking and drinks. Hot water can leach lead from old pipes.
- Wash children’s hands, toys, bottles, and pacifiers often, and teach children to wash their hands after playing outside.
- Don’t let children play in soil.
- Remove shoes in your house.
- If your home is being renovated or painted, make sure your contractor is lead-safe certified and follows lead-safe work practices.
- Try not to remain in your home if lead is being removed, or if a room that might have lead is being renovated.
