Lead Exposure Risk Index


Years of Collection:

Why do we measure lead exposure?

Elevated blood lead levels are associated with impaired brain and nervous system functioning, slowed development in children, behavior problems, and poorer performance in school.(1) Most children with elevated blood lead levels live in or regularly visit housing that has old, decaying lead paint, exposing them to leaded paint chips and dust.(1) Housing built before 1978 is the most likely to have lead-based paint or lead-containing pipes. Residents with low incomes may also struggle more with the cost of maintaining older housing stock, leaving them vulnerable to the health impacts of poor housing quality.(2,3)

How do we measure lead exposure? 

Since data on blood lead levels is difficult to obtain directly, we instead use two metrics that are well-established predictors of lead exposure.(4)

Housing with Potential Lead Risk

Older homes generally have a greater risk of lead paint.(5) “Housing with Potential Lead Risk” is the percent of housing stock with the potential for elevated lead risk because of the age of the housing in the congressional district. 

Lead Exposure Risk Index

The “Lead Exposure Risk Index” is a score of overall lead exposure risk obtained by combining the “Housing with Potential Lead Risk” information with the percent of people who live in poverty in the congressional district, since both housing age and poverty are major predictors of lead exposure.(3, 6-8)

Check out our blog post on these metrics for more information.

Strengths of Metrics

Limitations of Metrics

Housing age contributes to some of the main sources of lead exposure: lead paint, exposure to soil/dust with traces of lead, and lead pipes.(1)

The “Lead Exposure Risk Index” highlights areas with the greatest risk of lead exposure due to both housing age and poverty, which can help communities target lead abatement strategies to where they are needed most.

High scores on these measures tell you about the lead risk in an area, but may not accurately predict an individual’s actual chance of lead exposure.(4)

These metrics do not reflect lead removal or improvement interventions that may have happened or that may be underway now through public or private initiatives.

These metrics are very slow to change, since housing age does not change unless buildings are demolished or new housing is built.


Housing with Potential Lead Risk

We count the number of housing units in each of five time periods: pre-1939, 1940-59, 1960-79, 1980-99, and 2000 or newer. The count of housing units in each time period is weighted by the likelihood of lead exposure in housing of that era, which results in an overall percent of area housing likely to have some risk of lead exposure. 

Lead Exposure Risk Index

We took the “Housing with Potential Lead Risk” and factored in information about the percentage of households living at or below 125% of the poverty level. We standardized, weighted, summed, and ranked these values from 1, or lowest risk, to 10, or highest risk, to create a scale of overall lead exposure risk.

These analyses were based on methods developed by the Washington State Department of Health/Vox Media.(4) These metrics were calculated by aggregating estimates from smaller geographies to the congressional district level. For more information on the calculation, please refer to the Congressional District Health Dashboard Technical Document.  

Data Source

Estimates for the “Housing with Potential Lead Risk” metric are from American Community Survey data using the B25034 table. Estimates for the “Lead Exposure Risk Index” metric are from American Community Survey data using the B25034 and S1701 tables. 


  1. Academy A, Pediatrics OF, Exposure L. Lead Exposure in Children: Prevention, Detection, and Management. Pediatrics. 2005;116:1036-1046.

  2. Shai D. Income, housing, and fire injuries: a census tract analysis. Public health reports (Washington, DC : 1974). 2006;121:149-154.

  3. Vivier PM, Hauptman M, Weitzen SH, Bell S, Quilliam DN, Logan JR. The important health impact of where a child lives: neighborhood characteristics and the burden of lead poisoning. Maternal and child health journal. 2011;15(8):1195-1202.

  4. Frostenson S, Kliff S. The risk of lead poisoning isn't just in Flint. So we mapped the risk in every neighborhood in America. 2016. https://www.vox.com/a/lead-exposure-risk-map. Accessed January 8, 2018.

  5. Jacobs DE, Clickner RP, Zhou JY, et al. The prevalence of lead-based paint hazards in U.S. housing. Environmental Health Perspectives. 2002;110:599-606.

  6. Vaidyanathan A, Staley F, Shire J, et al. Screening for lead poisoning: a geospatial approach to determine testing of children in at-risk neighborhoods. J Pediatr. 2009;154(3):409-414.

  7. Lanphear BP, Byrd RS, Auinger P, Schaffer SJ. Community characteristics associated with elevated blood lead levels in children. Pediatrics. 1998;101(2):264-271.

  8. Shenassa ED, Stubbendick A, Brown MJ. Social disparities in housing and related pediatric injury: a multilevel study. Am J Public Health. 2004;94(4):633-639.

Last updated: January 24, 2023