Tetrachloroethylene levels in residential dry cleaner buildings in diverse communities in New York City

Environmental Health Perspectives, Oct, 2005 by Michael J. McDermott, Kimberly A. Mazor, Stephen J. Shost, Rajinder S. Narang, Kenneth M. Aldous, Jan E. Storm

Apartment indoor air perc levels by building type for this study and for studies completed before adoption of the New York State and New York City dry cleaner regulations in 1997 are summarized in Table 4. Mean (geometric) indoor air perc levels in residential dry cleaner buildings in New York City decreased from about 340-360 [micro]g/[m.sup.3] during the 1994-1997 period to 34 [micro]g/[m.sup.3] during the 2001-2003 period. Maximum indoor air perc values decreased from 25,000 to 5,000 [micro]g/[m.sup.3] over the same period. Mean perc levels in buildings without dry cleaners appears to have remained constant at 3 [micro]g/[m.sup.3] and mean perc level in buildings that had only drop-off facilities was only slightly higher at 6 [micro]g/[m.sup.3].

Importantly, when only buildings located in minority and/or low-income neighborhoods are considered, mean (geometric) perc levels are close to or exceed the NYSDOH residential air guideline of 100 [micro]g/[m.sup.3]. Table 4 shows that indoor air perc level in 29 apartments in 10 dry cleaner buildings located in a minority census block group averaged 76 [micro]g/[m.sup.3], compared with 19 [micro]g/[m.sup.3] in 36 apartments in 14 buildings located in nonminority census block groups. The mean perc level in 11 apartments in 5 dry cleaner buildings located in a low-income census block group was 256 [micro]g/[m.sup.3], compared with 23 [micro]g/[m.sup.3] in 54 apartments in 19 buildings located in non-low-income census block groups. Thus, residents of dry cleaner buildings in minority, low-income areas appear to have disproportionately elevated exposures to perc even though, overall, perc levels have decreased since adoption of the 1997 dry cleaner regulations.

Discussion

We determined indoor air perc levels in residential buildings with on-site dry cleaners and in nearby residential buildings without dry cleaners in the borough of Manhattan, New York City. Buildings sampled included only those that were evaluated for NYC Perc Project inclusion and that met building inclusion criteria (e.g., no other source of VOCs present, occupied residences present). Additionally, individual apartments sampled included mostly those meeting NYC Perc Project household inclusion criteria (i.e., presence of an adult and child residing in the same household for at least 1 year with no other VOC exposures or certain medical conditions), although five sampled apartments included only adult residents. Thus, the sample obtained is not a truly random sample of all dry cleaner buildings in the study area. However, socioeconomic characteristics of the census block groups where sampled buildings are located reflect socioeconomic characteristics of their larger ZIP code area, are equivalent to census block groups where buildings that were not sampled are located, and are correlated with sampled household self-reported socioeconomic characteristics. Thus, conclusions drawn with respect to sampled building neighborhood characteristics and indoor air perc level are likely to be applicable to other residential buildings matching NYC Perc Project building inclusion criteria (e.g., dry cleaner using perc on site; no other source of VOCs).