Lead exposure remains an environmental health concern

Cade Martin / Dawn Arlotta / USCDCP

Lead exposure continues to be an ongoing and preventable health issue for children. Although lead is hazardous to humans of all ages, children ages six and under are at a greater risk of harm because of their rapidly growing brains.

Younger children are especially at risk for environmental lead exposure because they frequently touch the ground and put their hands in their mouths. These behaviors can result in lead exposure if lead dust is present in the home or the soil.

Lead exposure is usually measured with a simple blood test, where an elevated lead level in children is a level of five micrograms per deciliter (mg/dL) or more. The Centers for Disease Control and Prevention (CDC) collects lead data from states, and lead was the first non-infectious laboratory test to be monitored nationally in this way.

National data from 2012-2017 shows 2-3% of children ages six and under who were tested had elevated lead levels, though Minnesota has continued to have under 1% elevated lead levels in children. However, only 16-19% of children under six are being tested nationally, and we are only doing slightly better in Minnesota, testing 20-22% of children.

Exposure to lead can occur from many sources in the home and local environment. At home, lead can be part of paint in homes built before 1978 (and more before 1950). Lead can also be in tap water if the plumbing in the home contains lead, such as with older plumbing before 1980.

According to Minnesota Department of Health (MDH) data, about two-thirds of homes in Hennepin and Ramsey counties were built before 1980, and about one quarter of homes in Hennepin County and over 30% of homes in Ramsey County were built before 1950. Outside the home, air and soil can contain lead, especially in areas with industrial buildings or near airports because of the type of gas used.

Like most health conditions, lead exposure is also more common in lower-income areas and in non-White populations. In Minnesota, the Black and Native American populations have four times higher rates of poverty compared to the White population.

National data has demonstrated a higher average lead level in Black children compared to White children. Unfortunately, state-level reporting of race in Minnesota is not complete enough to evaluate inequities in lead exposure in Minnesota children based on race. Elevated blood lead levels were found in 2% of children in the cities of Minneapolis and St. Paul, which is twice as much as in the rest of the Twin Cities Metro Area and in the entire state.

Lead exposure can also occur because of what we bring back to the home. Products made outside of the United States may contain lead, such as toys, jewelry, candy, home remedies or cosmetics. Lead dust can also be brought home if lead is used in the workplace, such as was seen in Minnesota in 2019 from workers at a company that produces fishing sinkers and lures.

The long-term consequences of lead exposure for children are damage to the brain and nervous system, which can impact hearing, speech, growth, development, learning and behavior. Research has shown lower school performance and problems with attention in children with long-term lead exposure. These same brain-related effects have continued into adulthood in longer research studies.

The good news is that lead exposure is 100% preventable. In the home, paint and water can be tested for the presence of lead and can be removed from the home by specialists with the appropriate equipment.

Renters can find out about their rights related to lead in the home on the MDH website (see below). The MDH’s website also has lots of information about removing lead sources from the home and otherwise reducing the risk of exposures in children.

The simplest way to understand the risk of environmental lead exposure is to have your children tested. MDH recommends testing children at one and two years old, as well as any other children under six years old who may be at risk of lead exposure.

Children in this age range should be having visits with their doctor multiple times per year before the age of two, so this screening should happen as part of a child’s regular visits to the doctor.

Even though lead has been a well-known environmental hazard for a long time, the health hazards of lead exposure are still not known to everyone.

MDH has excellent resources available on their website (www.health.state.mn.us) where you can learn more about risks and recommendations regarding lead exposure and prevention.

Dr. Zeke McKinney practices clinical occupational and environmental medicine (OEM) for HealthPartners in St. Paul and Anoka, MN, and he is one of few clinicians in Minnesota who evaluates patients for environmental toxicologic exposures. He is also a faculty physician in the HealthPartners OEM Residency where he trained and an affiliate assistant professor at the University of Minnesota School of Public Health.