Selecting a Lead Hazard Control Strategy Based on Dust Lead Loading and Housing Condition: I. Methods and Results

Abstract

A methodology was developed to classify housing conditions and interior dust lead loadings, using them to predict the relative effectiveness of different lead-based paint hazard control interventions. A companion article in this issue describes how the methodology can be applied. Data from the National Evaluation of the HUD Lead Hazard Control Grant Program, which covered more than 2800 homes in 11 U.S. states, were used. Half these homes (1417) met the study's inclusion criteria. Interior interventions ranged from professional cleaning with spot painting to lead abatement on windows, and enclosure, encapsulation, or removal of other leaded building components. Modeling was used to develop a visual Housing Assessment Tool (HAT), which was then used to predict relative intervention effectiveness for a range of intervention intensities and baseline floor and windowsill dust lead loadings in occupied dwellings. More than 117,000 potential HATs were considered. To be deemed successful, potential HATs were required to meet these criteria: (1) the effect of interior strategy had to differ for HAT ratings of good vs. poor building condition and/or baseline dust lead loadings; (2) the HAT rating had to be a predictor of one year post-intervention loadings; (3) interior intervention strategy had to be a predictor of one-year loadings; (4) higher baseline loadings could not be associated with lower one-year loadings; and (5) neither exterior work nor site/soil work could result in higher predicted one-year loadings for either HAT rating. Of the 1299 HATs that met these criteria, one was selected because it had the most significant differences between strategy intensities when floors and sills were considered together. For the selected HAT, site/soil work was a predictor of one-year loadings for floors (p = 0.009) but not for sills (p = 0.424). Hazard control work on the building exterior was a predictor of both sill and floor one-year loadings (p = 0.004 and p < 0.001, respectively). Regardless of the type of interior intervention strategy, interior work was a predictor of both floor and sill one-year loadings (each p ≤ 0.001).

Keywords:

• housing condition
• interim control
• intervention
• lead abatement
• lead hazard control

ACKNOWLEDGMENTS

The authors wish to thank the staff of the participating Lead Hazard Control grantees (Alameda County, California; Baltimore, Maryland; Boston, Massachusetts; California; Chicago, Illinois; Cleveland, Ohio; Milwaukee, Wisconsin; Massachusetts; Minnesota; New Jersey; New York City, New York; Rhode Island; Vermont; and Wisconsin) for their tireless efforts and dedication to making this project a success. The authors also want to acknowledge the guidance of Nick Farr and Ron Jones on this project.

The analysis and writing of this article were funded under Howard University Center for Urban Progress subcontract 633840-005442 of HUD Lead Technical Studies Grant No. DCHBC0001-03. The Evaluation by NCHH and the University of Cincinnati was supported by the U.S. Department of Housing and Urban Development (HUD) Grant Nos. MDLR005-94 and OHLPR0010-95 and by HUD grants to each of the individual LHC grantees.

The research reported in this article was conducted in accordance with national and international guidelines for the protection of human subjects. Each individual grantee collecting data obtained its own Institutional Review Board approval.

The conclusions reached are those of the authors and do not necessarily represent those of the sponsor.

Notes

^ANon-intact is defined as 0.5 ft² or more of deteriorated paint on large surfaces, or 1% or more of the total surface area of small building components.

^BThis information was gleaned from the Evaluation paint inspection forms.

^APaint Stabilization—The process of repainting surfaces coated with lead-based paint, which includes the proper removal of deteriorated paint and priming. Complete paint stabilization is the repainting of all of a surface, while spot painting is repainting part of a surface.

^BReplacement—The removal/replacement of a building component that was coated with lead-based paint.

^CWindow Treatments—The process of eliminating lead-containing surfaces on windows that are subject to friction or impact through the removal of paint or enclosure of certain window components.

^DPaint Removal—The complete removal of lead-based paint by wet scraping, chemical stripping, or contained abrasives.

^EEnclosure—The application of rigid, durable construction materials that are mechanically fastened to the substrate to act as a barrier between lead-based paint and the environment.

^ACI = confidence interval.

*Deceased