Find the lead in Pennsylvania homes before a child's blood test does
Pennsylvania's lead response is built around a child's blood test. By the time anyone looks at the house, the child has already been exposed. I think the search should start with the house, and I have the data to do it. Here's how it works now, what I'd change, and the state's own numbers.
Eric Ritter, Fluoro-Spec Inc. · October 2026
7,840Pennsylvania children under 6 with confirmed elevated blood lead (3.5 µg/dL or higher) in 2023.
About 1 in 5children under 6 got a blood lead test at all in 2023. That's 166,915 of 806,975.
41%of children with a high first finger-stick didn't get a proper retest within 12 weeks (6,240 of 10,592 did).
5thin the country for the share of homes built before 1950, when lead paint was most common.
All four from the Pennsylvania Department of Health, 2023 Childhood Lead Surveillance Annual Report.
Where the old houses are
The state's own report ties the higher rates in its cities to older housing, and the housing data is public. The first map shades every county by how much of its housing was built before 1950. Switch it to see how many tested kids were confirmed with elevated blood lead in 2023. The counties with a dark outline are the ones where I have every house.
Housing age: Census Bureau, American Community Survey 2020 to 2024, table B25034. Blood lead: Pennsylvania Department of Health, 2023 report, Table 12, children under 6, confirmed at 3.5 µg/dL or higher as a share of those tested. Testing rates run from about 10% to 31% depending on the county, so a low number can also mean few kids were tested, and in small counties one or two cases swing the percentage a lot.
Every house, by the year it was built
Each dot is a parcel with a recorded build year, from the county's own property records. Red is before 1950, when lead paint was most common. Amber is 1950 to 1977, before the federal ban on lead paint in homes. Green is 1978 or later. Scroll or pinch to zoom, drag to move, and hover over a dot to see the year.
Loading parcels…
How it works now
This is the path a family goes through today, with the numbers from the state's 2023 report.
- The child has to get tested. Pennsylvania doesn't require it statewide. Only Allegheny County and Philadelphia do. In 2023 about one in five children under 6 in the state were tested.
- A high finger-stick has to be confirmed. 10,592 children had a first finger-stick at 3.5 µg/dL or higher. 6,240 of them, 58.9%, got a venous test or a second finger-stick within 12 weeks. The rest didn't get one in that window.
- Then the house might get looked at. Outside the 11 county and city health departments that run their own programs, a state nurse calls the family and encourages them to ask their doctor whether the home needs an environmental investigation. The state health department's own lead hazard control program reports 340 environmental investigations since 2024 and more than 319 homes remediated in the last five years. Philadelphia, Allegheny and the HUD-funded programs fix homes on top of that. For scale, 7,840 children under 6 were confirmed elevated in 2023 alone.
- Meanwhile the family cleans without being able to see what they're cleaning. The advice is to wet-mop floors, wipe windowsills and wash hands while they wait for the inspection and the repairs. Lead dust is usually too fine to see, so they can't tell where it's coming from or whether they got it.
What I'd do instead
Three changes, in the order a house would go through them.
1. Find the likely houses by address, before a child is exposed
Lead paint follows the age of the house. HUD's national survey found it in 87% of homes built before 1940. Pennsylvania has some of the oldest housing in the country, so the houses most likely to have lead can be listed by address from public records.
I have the build year for 1,398,663 parcels in four Pennsylvania counties (every one of them is on the map above) and a risk score for every census tract and ZIP code in the state. 784 of Pennsylvania's 3,402 census tracts rank in the top 10% of the country for predicted childhood lead risk, and about 161,000 children under 5 live in them.
| County | Median year built | Built before 1940 | Built before 1978 | Parcels with a build year |
|---|---|---|---|---|
| Philadelphia | 1925 | 315,763 (58.4%) | 489,290 (90.6%) | 540,234 |
| Allegheny | 1950 | 162,335 (36.2%) | 361,076 (80.5%) | 448,767 |
| Montgomery | 1967 | 51,240 (19.4%) | 158,000 (59.8%) | 264,153 |
| York | 1973 | 33,121 (22.8%) | 79,732 (54.8%) | 145,509 |
The risk model is published in GeoHealth and was checked against measured childhood blood lead in eleven states. Pennsylvania wasn't one of them, so I checked it in Allegheny County against the health department's 2025 blood lead results by ZIP. The rank correlation was 0.80 across the 75 ZIPs with at least 50 children tested. The full county pack is at detectlead.com/allegheny.
With a list like this, a program can mail or knock on the oldest houses with young kids first, instead of waiting for a lab report to say which one.
2. Let the people who live there look for themselves
Fluoro-Spec is a spray. Where there's lead in paint or dust, it glows bright green under the UV light that comes with the kit, in about 30 seconds. A parent can see which windowsill, floor or porch has lead on it, clean that spot, and spray again to check. A program kit costs about $50 and does around 500 sprays, so each look costs about a dime. Several Pennsylvania lead programs already have kits.
It's a screening tool. It isn't an EPA-recognized test kit under the Renovation, Repair and Painting rule, and it doesn't replace an XRF inspection, a risk assessment or a lab dust wipe where the law requires one. The chemistry is published (van Geen et al., 2024, Analytica Chimica Acta). I make and sell the kit, so that's my interest here.
3. Check the work before the clearance wipe
After lead hazard work, a certified examiner wipes the floors and sills and a lab decides pass or fail. In the national evaluation of HUD's lead grant program, about one in five units failed clearance on the first try, and that was under the old limits.
As of January 12, 2026, the clearance limits dropped from 10 to 5 µg/ft² on floors, from 100 to 40 on windowsills, and from 400 to 100 in window troughs. EPA estimates the new dust standards cost $207 million to $348 million a year nationally, including about $27 million a year for public housing authorities to keep public housing in line with HUD's lead rule. HUD's per-unit planning figure for its lead hazard reduction grants went from $12,000 to $14,000 in two years, and HUD puts the increase on the stricter cleaning and clearance requirements.
A failed clearance means more cleaning, another wipe, another lab fee, and often more days the family can't move back in. A crew that sprays the work area before the examiner shows up can see the dust that's left and clean it first. I'd rather spend a dime finding the dust than pay for a second clearance.
The 12 Pennsylvania cities the state reports separately, 2023
Children under 6. Sorted by the share of tested children with confirmed elevated blood lead. In York, one in seven tested children was confirmed elevated, the highest of the twelve.
| City | % of tested | Confirmed elevated | Tested | Children under 6 | County |
|---|---|---|---|---|---|
| York | 14.27% | 123 | 862 | 3,406 | York |
| Reading | 13.67% | 325 | 2,378 | 8,810 | Berks |
| Scranton | 11.60% | 103 | 888 | 4,490 | Lackawanna |
| Wilkes-Barre | 11.48% | 100 | 871 | 3,175 | Luzerne |
| Lancaster | 10.53% | 150 | 1,424 | 4,557 | Lancaster |
| Erie | 10.22% | 183 | 1,791 | 6,779 | Erie |
| Harrisburg | 8.15% | 106 | 1,301 | 4,635 | Dauphin |
| Pittsburgh | 6.46% | 286 | 4,428 | 16,101 | Allegheny |
| Upper Darby Township | 6.10% | 112 | 1,836 | 6,266 | Delaware |
| Philadelphia | 5.75% | 1,841 | 32,001 | 116,945 | Philadelphia |
| Allentown | 4.89% | 124 | 2,538 | 10,733 | Lehigh |
| Bethlehem | 3.52% | 27 | 767 | 3,956 | Northampton/Lehigh |
Pennsylvania Department of Health, 2023 Childhood Lead Surveillance Annual Report, Table 10. Confirmed means one venous test or two finger-sticks at 3.5 µg/dL or higher, per the CDC 2016 case definition. Testing rates differ a lot between cities, so the percentages compare tested children, not all children.
Free for any Pennsylvania county
For any county in the state I can pull the tract and ZIP scores, write a need statement for a grant application, and produce address lists where the parcel data exists. I also write HUD lead grant applications for local governments for free. Allegheny is the worked example.
Sources
- Testing, confirmation, city and county figures, state program counts, and Pennsylvania's rank for pre-1950 housing: Pennsylvania Department of Health, 2023 Childhood Lead Surveillance Annual Report.
- Clearance limits, compliance date and cost estimates: U.S. EPA, Reconsideration of the Dust-Lead Hazard Standards and Dust-Lead Post-Abatement Clearance Levels, final rule, 89 FR 89416, November 12, 2024.
- Per-unit planning figures: HUD FY2026 and FY2024 Congressional Justifications, Lead Hazard Reduction.
- First-clearance failure: National Center for Healthy Housing and University of Cincinnati, Evaluation of the HUD Lead-Based Paint Hazard Control Grant Program, 2004 (20 to 24 percent).
- Lead paint by construction era: HUD, National Survey of Lead and Allergens in Housing, Volume I (Clickner et al., 2002), Table 4.1.
- Tract and ZIP risk model: Ritter, E. C. (2026), GeoHealth 10(10), e2026GH002053, open access. Census tract inputs from the American Community Survey 2018 to 2022.
- Parcel build years and locations, pulled October 2026: City of Philadelphia Office of Property Assessment; Allegheny County property assessments and parcel centroids (Western Pennsylvania Regional Data Center); Montgomery County parcels (December 2025 release) and York County parcels (September 2022 release), both published through the Pennsylvania Spatial Data Access (PASDA).
- County housing age: Census Bureau, American Community Survey 2020 to 2024 five-year, table B25034.
- Allegheny check: Allegheny County Health Department, Elevated Blood Lead Levels in Allegheny County in 2025.
- Kit chemistry: van Geen et al. (2024), Analytica Chimica Acta.
Questions, interviews or data requests: Eric Ritter, Fluoro-Spec Inc., eric@detectlead.com, 631-461-1838. Fluoro-Spec is a fast field screen that makes lead visible. It is not an EPA-recognized test kit and does not replace XRF or lab dust-wipe clearance where those are legally required.