Testing of Childhood Blood Lead Levels in Allegheny County
In 2021, the Allegheny County Health Department began collecting data for the new reference limit for elevated blood lead level of 3.5 μg/dL. This captured an additional 0.77% of the venous confirmed tests to be identified as elevated.
The number of children under 6 tested for blood lead levels with a venous confirmation in 2021 compared to 2020 is very similar. However, the percent of elevated lead levels at the 5 μg/dL reference level increased slightly from 1.67% to 1.91%, but is still lower compared to 2015–2018.
Weekly data from 2021 indicate steady blood lead level testing throughout the year, with more testing at the beginning of the year compared to the end.
In 2021, the greatest number of children under 6 were tested in the month of March and the least were tested in September.
The City of Pittsburgh consistently has a higher rate of confirmed elevated blood lead levels among children tested compared to the rest of the county. In 2021, the increase in percent of elevated blood lead levels (>= 5 μg/dL) in Allegheny County can be attributed to an increase in the City of Pittsburgh. Exposure to lead through lead-based paint in older homes is a significant risk for elevated blood lead and may help to explain the different rates of EBLL between the City and the remainder of the County. Lead paint was banned for consumer use in 1978; houses built prior to this are at an increased likelihood of containing lead-based paint. The older the home the higher the likelihood of containing lead-based paint. In the city of Pittsburgh an estimated 59.6% of housing units were built before 1950 compared to 39.1% of all county housing units. A higher percentage of homes built prior to the banning of lead paint likely contributes to an increased risk of exposure for children living in this area.
See "Housing Built Before 1980" and "Housing Built Before 1950" in the Maps and Testing Data section below.
Allegheny County’s universal testing policy requires a child’s first test to be completed between 9–12 months of age. According to Pennsylvania’s age range requirements for screening visits, 412 days is the maximum age to complete the 1 year screening visit. The percent of Allegheny County children who received testing for lead by the age of 412 days has increased since 2014. Of all Allegheny County children tested in 2021, 36.5% were under the age of 1.