Lead-Safe Wisconsin: Childhood Lead Poisoning Data and Data Analysis

The Wisconsin Childhood Lead Poisoning Prevention Program collects data to help lead-poisoned children. Program staff analyze the data to identify at-risk communities and other trends.

Use this page to learn about Wisconsin's childhood lead poisoning and testing rates. You can also find links to data publications and resources. Email the Wisconsin Childhood Lead Poisoning Prevention Program at DHSLeadPoisoningPrevention@dhs.wisconsin.gov with questions about this content.

Childhood Lead Poisoning Data Explorer Map

The interactive Childhood Lead Poisoning Data Explorer Map shows census tract level childhood lead poisoning data for Wisconsin children under age 6. The application also contains interactive maps of environmental and social characteristics that may be associated with an increased risk of lead exposure and lower blood lead testing rates among children.

View the Childhood Lead Poisoning Data Explorer Map

Wisconsin Childhood Lead Poisoning Data Explorer Map

Using maps to display lead poisoning data helps us:

  • Identify where the risk of lead exposure is greater.
  • Target efforts to control lead hazards before they poison children.
  • Target blood lead testing where children are at higher risk for poisoning.
  • Connect children with lead poisoning to recommended services.
  • Monitor progress toward eliminating childhood lead poisoning.
  • Identify and monitor trends in sources of lead exposure for children.
  • Develop and evaluate lead poisoning interventions and programs.

Learn about the data displayed in the application

The Childhood Lead Poisoning Data Explorer contains the following data at the census tract level:

Time trends

The Wisconsin Environmental Public Health Tracking Program lets you search for state and local data on childhood lead poisoning—as well as for data on other environmental public health topics. Read answers to FAQs (frequently asked questions) about the tracking program.

Join the environmental health listserv

Below you can find graphs showing the trends of the number of children tested for lead poisoning and the number of children found to be lead poisoned in Wisconsin.

Lead testing

The number of children under 6 tested for lead poisoning peaked from 2009-2011 with over 100,000 children tested per year. From 2012-2015, the number of children tested declined and then remained relatively stable at around 88,000 until 2019.

In 2020, the number of Wisconsin children tested for lead dropped significantly, and testing rates remain low:

  • In 2020, only about 65,000 children received a blood lead test (23% fewer than in 2019).
  • In 2021, only about 66,000 children received a blood lead test.
  • In 2022, only about 69,000 children received a blood lead test.
  • In 2023, only about 75,000 children received a blood lead test (12% fewer than in 2019).
Number of Wisconsin Children Tested for Lead, 2003-2023

Lead poisoning

While no safe blood lead level in children has been identified, the CDC uses a blood lead reference value to identify children with higher levels of lead in their blood compared to other children. From 2012-2021, the CDC blood lead reference value was 5 µg/dL. In late 2021, the CDC lowered their blood lead reference value to 3.5 µg/dL to better identify children with higher levels of lead in their blood compared to most children. As of January 2025, lead poisoning is defined in Wis. Stat. § 254.11(9) as a blood lead level of 3.5 µg/dL or more.

Over time, the percentage of tested children who have a blood lead level greater than or equal to 5 µg/dL has declined: In 2012, 6.2% of children who were tested for lead had a blood lead level greater than or equal to 5 µg/dL, compared to 3.2% in 2023. However, CDC’s updated blood lead reference value of 3.5 µg/dL will double the number of children who will be considered lead poisoned: In 2023, 6.3% of children who were tested for lead had a blood lead level greater than or equal to 3.5 µg/dL.

Percentage of Wisconsin children under age 6 with a blood lead level above CDC reference value between 2010 and 2023

Annual numbers

Lead poisoning data are reported for Wisconsin residents under age 6. While no safe blood lead level in children has been identified, the CDC uses a blood lead reference value to identify children with higher levels of lead in their blood compared to other children. This value has changed over time.

The reports below reference the blood lead level that reflected the CDC’s guidance at the time:

Last revised January 24, 2025