Lead dustfall from demolition of scattered site family housing: developing a sampling methodology.

Background: Over 3000 older homes containing lead-based paint are demolished in Chicago each year. While previous studies investigating large multifamily housing demolitions have shown high levels of lead in dustfall, dispersed single-family housing demolition have yet to be assessed. Presently, no standards exist to regulate the extent of lead dustfall from housing demolition.

Objectives: We studied ten residences in Chicago undergoing demolition and debris removal and compared dustfall rates to five standing homes from March to October 2006.

Methods: Dustfall was measured using a modification of APHA Method 502; samplers consisted of plastic buckets filled with 1l of deionized water, elevated to breathing zone height and placed around the demolition site perimeter. Laboratory analysis consisted of filtration, acid digestion and analysis by ICP/MS.

Results: During demolition, the geometric mean lead dustfall (n=43 at 10 locations) was 64.1 microgPb/m(2)/h (range: 1.3-3902.5), while the geometric mean lead dustfall for areas with no demolition (n=18 at 6 locations) was 12.9 microgPb/m(2)/h (range: 1.8-54.5). This difference was highly statistically significant (p=0.0004). When dust suppression measures were used, dustfall lead levels were lower, although the difference was not statistically significant. The geometric mean lead dustfall with dust suppression (n=25 at five locations) and without (n=22 at six locations) was 48 Pbmicrog/m(2)/h and 74.6 microgPb/m(2)/h, respectively.

Conclusion: Demolition dustfall lead levels are much higher than background levels of lead during demolition of single-family housing and may constitute a yet uncharacterized but important source of lead exposure to nearby residents. Simple dust suppression methods are likely to reduce the contamination considerably.