VOC sampling locations table for Ground Zero area, Jan 2002

NYC 9/11 Public Portal Document

IV. Discussion

Samples of fallen dust were collected at various around the WTC site caused a mild degree of pulmonary locations in the immediate vicinity of the WTC site one inflammation in mice (7% neutrophils in BAL fluid), and and two days after the WTC disaster, and were examined had no effect on parameters of acute lung injury at a dose by several physical and chemical techniques. Both coarse of 100 pg instilled directly into the limgs. ROFA, a toxic unfractionated and fine size-fractionated WTC PM positive control fine PM sample, caused a much higher samples were composed primarily of calcium-based degree of lung inflammation and lung injury at the same compounds such as calcium sulfate (gypsum) and calcium dose. However, mice instilled with 100 pg pooled WTC carbonate (calcite; the main component of limestone). PM2.5 had highly significant increases in airway These and other compounds and elements found in the responsiveness to methacholine (Meh) aerosol challenge, WTC PM samples are indicative of crustal material- which were significantly greater than that of ROFA. Mice derived building materials such as cement, concrete exposed to lower doses of pooled WTC PM2.5 (10 pg and aggregate, ceiling tiles, and wallboard. Both gypsum and 31.6 pg) and mice exposed by nose-only inhalation calcite irritate the mucus membranes of the eyes, nose, (estimated to have about 14 pg WTC PM2 5 deposited in throat, and upper airways (Stellman, 1998). Calcium the respiratory tract) did not have any biologically carbonate dust causes coughing, sneezing, and nasal significant changes in methacholine responsiveness or irritation (NLM, 2002). These minerals are often neutrophilic inflammation. These dose-response contaminated with small amounts of silica, which is the relationships and the lack of effect in nose-only exposure main concern for occupational health hazards (Stellman, suggest that inhalation of relatively high doses of WTC 1998). Minor amounts of silica (quartz) were detected in PM2.5 are necessary to elicit respiratory effects in people. the WTC PM samples Mice exposed to samples of WTC PM2 5 from the 7 Our chemical analysis generally agrees with the individual sites around Ground Zero had greater lung extensive analysis of WTC PM performed by the USGS inflammation (2 to 4-fold) than mice exposed to the WTC (USGS, 2002). Levels of carbon were relatively low, PM2.5 sample pooled from these sites. These findings suggesting that combustion-derived particles did not form occurred in separate experiments and would need to be a significant fraction of these samples recovered in the confirmed by a direct comparison, but nonetheless all immediate aftermath of the destruction of the towers. groups of mice exposed to the individual site samples Lastly, there was no evidence of significant asbestos developed hyperresponsiveness to Meh aerosol challenge, contamination of the samples used in these studies, similar to mice exposed to the pooled sample. No although the physical analyses conducted were not particular pattern ofresponses was found corresponding to specifically focused on definitive asbestos quantitation. the geographical location where the samples were taken. As of May 23,2002, the U.S. EPA had analyzed 9,544 air Pulmonary inflammation in mice exposed to individual samples in Lower Manhattan since September 11, and site WTC PM2.5 samples diminished from 1 day to 3 days found elevated levels of asbestos in only 21 samples (EPA, after exposure, although hyperresponsiveness to Meh 2002c). aerosol did not diminish significantly. Further The effects of exposure to samples of WTC PMj j on experiments would be necessary to determine the respiratory parameters, pulmonary inflammation, and lung persistence of pulmonary responses in mice, which may injury were investigated in young adult female CD-I mice, lead to insights into whether any WTC PM-associated an outbred strain expected to have significant variability effects which may exist in people are persistent. in biological responses, in three separate experiments. A The results of these studies should be examined in the pooled sample of WTC PMjs composed of roughly context of previous studies of the effects of equivalent amounts of samples from 7 different locations

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