Blood lead testing by birth year
Children tested in Minnesota:
Children under age 6, and especially those aged 1 to 3, are most vulnerable to lead exposure. Testing the blood lead levels of children can help catch lead exposure before it has the most harmful effects.
Determining the number of children tested for blood lead before they are 3 years old is important to measure trends and identify disparities in testing coverage among those most at risk.
Lead testing is not universal in Minnesota. Children with risk factors for lead exposure (such as older housing or poverty status) are targeted for testing. This includes all children who live in Minneapolis or St. Paul and all children who receive services from Minnesota Care or Medical Assistance, as well as any child who lives in or regularly visits a home, childcare, or other building built before 1978. Learn more about MDH Blood Lead Guidelines.
Indicators on this page track blood lead testing by birth year (cohort method) and include blood lead tests up to 3 years of age.
Children tested by 3 years of age. The Minnesota trend line is the statewide average and includes all children in the state. The Metro trend line represents children living in the 7-county Twin Cities metropolitan area. Source: MDH Blood Lead Information System.
The most recent birth cohort to have been observed for a full three years is children born in 2017. The percent of children tested increased from about 42% among children born in 2000 to about 81% among children born in recent years. Testing coverage rates vary slightly across regions (slightly higher in the 7-county Twin Cities Metro region and slightly lower in Greater Minnesota).
Children tested at 1-year and 2-year well child visits in Minnesota, by birth year
Children tested by 3 years of age. Source: MDH Blood Lead Information System.
In recent years, about 70% of children were tested around the time of their 1-year well-child visit (9-18 months) and about 45% were tested around the time of their 2-year well-child visit (18-36 months). Only about a third of children (36%) were tested at both their 1- and 2-year well-child visits.
MDH guidelines recommend screening children who are at risk for lead exposure at both one and two years of age. At-risk children aged three to six who have not been previously screened should also be screened. Children tested at one year of age should be tested again at two years even if the blood lead level was low at the one-year test since risk behaviors related to lead exposure change as a child develops. In Minnesota, about half of children tested around one year of age are tested again at two years.
Why should two-year-old children be tested?
Two-year-old children are more mobile and interact with their environments differently than one-year-old children. This can change the risk for lead exposure between these ages, even if the child’s house or other risk factors do not change. This is supported by MDH surveillance data; about 0.5% of children with non-elevated (<5 mcg/dL) blood lead levels measured at one year of age who were tested at two years of age have a confirmed elevated blood lead level at the time of the second test. This indicates that the practice of not testing children at two years of age may lead to lead-exposed children going undetected.
To see other tables and charts on childhood lead exposure, see:
- Annual blood lead testing
- Annual blood lead levels
- Blood lead levels by birth year
- Risk factors (housing age and poverty)
- Childhood lead exposure by county (map)
- Childhood lead exposure by census tract (map)
- Health inequities in childhood lead exposure
Last updated May 2022