EPA interim final report on WTC background study, April 2003

NYC 9/11 Public Portal Document

levels, with an average ratio of 0.5 (ATSDR 1999).

7.1.6 Residential Settled Lead Dust Measurements Lanphear et al. (1995) reported lead loading measurements from a study of residences of205 children in Rochester, NY. House dust samples were collected using two vacuum methods and a wipe method. The geometric mean values fi-om the microvacuum measurements were 1 pg/fi? and 3 pg/tf for noncarpeted floors and carpeted floors, respectively. The geometric mean value from their wipe sample measurements were 16 pg/tf and 11 pg/ft^ for noncarpeted floors and carpeted floors, respectively.

Lanphear et al. (1998) reported a geometric mean for floor dust lead loading of 13.5 fJ-g/ft^ from their pooled analysis of 12 epidemiologic studies.

Gallicchio et al. (2002) compared household lead exposure assessment methods in an old urban community (although the specific locale was not identified). The median values for dust lead loading were 12 pg/ft^ and 5 pg/tf for noncarpeted floors and carpeted floors, respectively. The measurements showed a large variation in lead load levels. Table 7-3 is extracted from the report’s statistics summary.

The U.S. Department of Housing and Urban Development (HUD 2001) reported the arithmetic mean for floor dust lead loading stratified by geographic location and age of housing. Table 7-4 is extracted from the HUD summary statistics.

7.1.7 Dioxins in Soil and Settled Dust ATSDR (1998) concluded that concentrations of chlorinated dibenzo-p-dioxins (CDDs) in soil are typically higher in urban areas than in rural areas. The highest CDDs in soil concentrations are associated with industrial sites, with CDD levels ranging from the hundreds to thousands parts per trillion. In general, the concentration of CDDs in soil near the site of a municipal waste incinerator would increase in concentration with increasing degree of chlorination. Heptachlorinated dibenzo-p-dioxin (HpCDD) and octa-chlorinated dibenzo-p-dioxin (OCDD) congeners are typically found at higher concentrations than the tetrachlorinated dibenzo-p-dioxin (TCDD), pentachlorinated dibenzo-p-dioxin (PeCDD), and hexachlorinated dibenzo-/7-dioxin (HxCDD) congeners in soil and sediments.

Christmann et al. (1989) collected indoor household dust samples and analyzed the dust samples for CDDs. The dust samples were collected with a vacuum cleaner from rooms with furniture treated with a wood preservative. The wood preservative contained CDD-contaminated pentachlorophenol (PCP). Average mass concentrations of CDDs found in the dust samples were: 191 |xg/kg of OCDD, 20 pg/kg of HpCDD, 2.5 pg/kg of HxCDD, 0.9 pg/kg of PeCDD, and 0.2 pg/kg of TCDD.

WORLD TRADE CENTER BACKGROUND STUDY 33

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