Childhood Lead Exposure Map: MNPH Data Access

There is no safe level of lead exposure. Even low levels of lead exposure can harm a child.

“Percent tested” describes the proportion of children tested by 3 years old.

“Percent elevated” describes the proportion of children with an elevated blood lead level (5+ mcg/dL) among children tested. Because lead testing was not universal in Minnesota until 2022, the “percent elevated” indicator cannot be generalized for the overall population of children living in Minnesota.

This map uses a birth cohort (group) approach, to determine how many children born in a specific year were tested before 3 years old, and how many of those tested had an elevated blood lead level.

Lead testing was not universal in Minnesota until 2022. Minnesota guidelines did not recommend universal screening for childhood lead exposure until 2022. In the data shown here, lead testing was targeted for children with risk factors for lead exposure.

The Centers for Disease Control and Prevention (CDC) updated their reference level from 5 micrograms per deciliter (5 mcg/dL) to 3.5 mcg/dL in 2021 to identify children with blood lead levels that are much higher than most children’s levels. This new reference level is based on the U.S. population of children one to five years old who are in the highest 2.5% of children when tested for lead in their blood, based on the National Health and Nutrition Examination Survey (NHANES) data. Reference levels are expected to decline over time as blood lead levels in U.S. children decline.

Map categories for the “percent tested” indicator were created using natural breaks for 2018 birth cohort (group) data.

Map categories for the “percent elevated” indicator (the difference compared to Minnesota) were calculated by comparing the 95% confidence interval of “percent elevated” in each county to the 95% confidence interval for “percent elevated” statewide. Using difference from the mean methodology, counties were then classified as significantly different from MN if the intervals do not overlap – either higher than the state mean (average) or lower than the state – or as no different from the state if intervals overlap.

A small amount of blood lead tests have an unknown county of residence and these are included in the Minnesota total.

In Minnesota, when a child has a venous blood lead level of 15 mcg/dL or higher, state statute mandates environmental interventions to identify and eliminate sources of lead exposure (e.g., finding and cleaning up deteriorated lead-based paint.)

The CDC and National Tracking Network define a confirmed elevated blood lead level as a single elevated venous test (from a vein) OR two elevated capillary tests (from a finger prick) within 12 weeks. However, Minnesota statute requires a venous test as confirmation before an environmental intervention is mandated. The Tracking definition of a confirmed test may include some cases that did not have venous confirmation. All data shown on the map use the Tracking definition of a confirmed elevated blood lead level.

The number of elevated blood lead levels (EBLLs) is based on the number of children that had an EBLL, and not the total number of results or tests. Each child can only contribute one EBLL.

Percentages flagged with an asterisk (*) should be interpreted with caution since they are based on less than 20 EBLLs and the percent elevated can change dramatically with the addition or subtraction of one EBLL.

For additional information, visit Childhood Lead Poisoning Risk Factors, and the "About the Childhood Lead Exposure Data" page.