Lead Testing Case Counts and Data

It is important for children to be tested for lead poisoning.  Statewide testing rates are extremely low, and Snohomish County’s testing rates are lower than the state average. This means the majority of children with lead poisoning are not being identified for protection.

The blue line in the graphic below indicates that children who would be expected to have lead in their blood have actually been tested and confirmed at a ratio of 1:1 (one identified case of lead in blood per each predicted/expected case of lead in blood).

Lead Testing by State

The graph depicts how successful states were at identifying children with lead in their blood (at values over 5 micrograms per deciliter). The blue horizonal line represents the point where the number of children who would be expected to have that level of poisoning matches the number who have actually been identified. The majority of states fall well below this line. This means they are not identifying all the children who need to be identified. Washington is at the very bottom and Snohomish County is even lower than the state ratio. We are not identifying cases that exist. Identifying cases is crucial so that we can help protect children by removing their exposure to the source of lead. Doing so can especially help children from lower income families as well as children who are Black, Indigenous, and People Of Color. Communities of color are disproportionately affected by lead poisoning.

Graph adapted from "Assessing Child Lead Poisoning Case Ascertainment in the US, 1999-2010." Pediatrics. 2017; 139(5). doi: 10. 1542/peds.2016-4266

Snohomish County and statewide testing rates are similar but overall extremely low. Testing rates need to increase so that children who have lead in blood are identified and protected from further exposure to damage.

Testing Rates for Children in Snohomish County

9-15 Months
21-27 Months

Snohomish Co.Rest of WASnohomish Co.Rest of WA
# of Children Tested79510,1514903,892
Testing Rate8 out of 10012 out of 1004 out of 1004 out of 100
Population9,90480,06510,62080,552


Source: Washington State Department of Health Blood Lead Test Data Registry; Washington State Population Interim Estimates (PIE).

Note: 1 year of age and 2 year of age population estimates for 2020 from PopPIE were used to produce testing rates.