The Sixth Year Extension of the
National Evaluation

Ingestion and inhalation of lead dust has been linked to learning disabilities and lowered intelligence.

In 1992, the Department of Housing and Urban Development (HUD) began making grant funds available to state and local governments for the purpose of developing and implementing programs to identify and control lead-based paint hazards in eligible privately owned housing units. A year later, HUD contracted with the National Center for Healthy Housing (NCHH) to evaluate the interventions that the first round grantees were using to reduce lead hazards. The next year, three second round grantees were added, bringing the total to 14 state, county and city programs that were being evaluated. The overall purpose of the Evaluation of the HUD lead Hazard Control Grant Program (the Evaluation) was to measure the relative cost and effectiveness of the various methods used by the grantees to reduce lead-based paint hazards in housing. Although the Evaluation was a great success, questions remained after three years of follow-up about the long-term effectiveness of the treatments. Thus a Sixth Year Extension of the Evaluation was developed. 

Goals: The principle objective of the Six Year Extension Project was to determine if the benefits of any of three classes of intervention strategies cease prior to six years post-intervention. The study also compared the relative effectiveness after six years of the different classes of strategies, after controlling for such factors as exterior lead dust and soil and building upkeep. Data collection started in June 2001 and ended in June 2003.

Description: Under a contact from HUD, NCHH collaborated with Battelle Memorial Institute and University of Cincinnati to conduct the study. Four grantees participated in the Sixth Year Extension Project: St. Paul-Ramsey County Department of Public Health (representing Minnesota), City of Milwaukee Health Department; New York City Department of Housing Preservation and Development; and Vermont Housing Conservation Board.

Under the Evaluation study design, different interventions were categorized into treatment groups called "strategies." The most commonly used strategies were: cleaning and spot painting (strategy 02), complete painting (03), interventions with window interim controls (i.e., jamb liners, friction controls) (04), and interventions with window abatement (i.e., replacement and paint removal) (05).  In a more limited number of dwellings, full abatement was conducted (06). The study design assumed that at different points in time the strategies would begin to fail and leaded dust would significantly reaccumulate in the dwellings. Under the Sixth Year Extension Project, environmental data was collected six years after the completion of interventions in dwellings units that underwent low (02/03), medium (04/05), and high (06) levels of treatment to assess the longer-term effectiveness of the intervention strategies.

Results: Overall dust lead loadings on floors and window sills were lower six years post-intervention than at other post-intervention periods. Window trough dust lead loadings had increased since treatment, but remained 75% lower than before work. Six years post-intervention homes undergoing medium level treatments had lower window sill and trough dust lead loadings than homes undergoing low level treatments, but no difference was observed between treatments on floors. Homes treated with high level treatments had the lowest six year post-intervention dust lead loadings on floors and window sills: 1 µg/ft² and 19 µg/ft², respectively. 

Click here to download the summary of Evaluation of HUD-funded lead hazard control treatments at 6 years post-intervention, published in Environmental Research in January 2007.

For more information contact Jonathan Wilson at jwilson@nchh.org
(443 539-4162).

Research and Evaluation
(Active Projects)

Research and Evaluation
(Completed Projects)

Training and Technical Assistance
(Active Projects)

Training and Technical Assistance
(Completed Projects)

Demonstration

Policy