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

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

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 (Centers for Disease Control and Prevention) 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:

2020

2019

2018-2006

Time trends

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, Wisconsin saw a significant decline in the number of children who received a blood lead test, with only around 65,000 children tested. Overall, in 2020, there were 23% fewer blood lead tests done compared to 2019. In 2021, testing remained low with only around 66,000 children receiving a blood lead test.

Graph showing number of kids under age 6 tested for lead in Wisconsin from 2006 to 2021

Lead poisoning

While no safe blood lead level in children has been identified, the CDC (Centers for Disease Control and Prevention) 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. From 2012-2021, the CDC blood lead reference value was 5 µg/dL. In late 2021, the CDC updated 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. Lead poisoning is currently defined in Wis. Stat. § 254.11(9) as a blood lead level of 5 µg/dL or more.

Over time, the percentage of children tested for lead 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, but in 2021 it was 2.8% of children. However, the update of the CDC’s blood lead reference value will double the number of children who will be considered lead poisoned. In 2021, 5.6% of children who were tested for lead had a blood lead level greater than or equal to 3.5 µg/dL.

Graph showing percentage of children under age 6 in Wisconsin with blood lead levels over CDC reference values from 2012 to 2021

Last Revised: December 9, 2022