VOC sampling locations table for Ground Zero area, Jan 2002

NYC 9/11 Public Portal Document

III. Results

A. Chemical analysis of solid samples and liquid sample, preparation method for ICP, or the presence of extracts. other insoluble forms of calcium in the WTC3. The XRF 1. Endotoxin and pH levels. The pH of water- values are higher for most other elements, which reflects extracted WTC PM2.5 ranged from 8.88 in WTCE to 10.00 the incomplete dissolution of the WTC3 matrix by the in WTC8 (Table 2). The alkaline pH is consistent with weak (water) and moderate (IM HCl) extraction liquids. previous reports of WTC PM (USGS, 2002) and probably Elements such as magnesium and zinc, which exist in results from the building materials comprising much ofthe compounds more amenable to acid dissolution, agree more dust (see below). The pH of lyophilized WTC PM25 closely (Weast, 1985; Budavari, 1996). Elements such as reconstituted in unbuffered saline was very close to aluminum, iron, and titanium, which are in the form of neutral, while MSH was very slightly acidic and ROFA was moderately acidic (average 3.74 at 2 mg/ml). It is not Table 2. Endotoxin and pH Levels of PM Samples after Water Extraction and Resuspension in Saline. known why the pH of WTC PM2.5 should be close to neutral after reconstitution in saline; perhaps the salt Sample pH in Endotoxin pjj neutralizes a basic component of the extract. Endotoxin Code- water EU/ml Inhibition Saline' levels in WTC PM2 5 samples were minimal in comparison Water" 5.28 with other urban PM samples such as NIST 1649a, which WTC 8-100 10.00 0.50 none was also low (Table 2). Several thousand times this level WTC 11-100 9.16 0.25 none of endotoxin caused an acute neutrophilic response in the WTC 13-100 9.47 0.50 none lungs of CD-I mice (Dhingra et al., 2001). The level of WTC B-100 9.54 0.25 none endotoxin in the samples used in this study would not be WTCC-100 9.32 0.50 none anticipated to contribute directly to any inflammatory WTC E-lOO 8.88 0.25 none response in the lungs. WTC F-lOO 9.55 0.50 none 2. Elemental and Ion Analysis. The ICP data showed NIST-100' 4.20 25 none that water-soluble calcium and sulfate content amounted Saline 6.67 to 56-63% of the WTC PM2.5 samples (Table 3). In WTCX-10 7.38 general, the elemental and ion compositions were WTCX-31.6 7.38 consistent among the different samples tested. ICP data WTCX-100 9.35 7.36 for the 1M HCl-soluble extracts of WTC PM2 5 showed an MSH-100 6.61 additional 1-2 weight percent calcium content. This ROFA-100 3.74 increase may be attributed to calcite or other water­ insoluble calcium salts which are soluble in IM HCl (see ■WTCX indicates pooled sample of WTC8, WTC11,WTC13, below for data on compound analysis). There was no WTCB, WTCC, WTCE, and WTCF. "-100" indicates 100 pg/50 gl dose = 2mg/ml. "-31.6" indicates 31.6 gg/50 gl dose = 0.632 evidence of stainless steel contamination from the forceps mg/ml. "-10" indicates 10 gg/50 gl dose = 0.2 mg/ml. used to handle the WTC PM filters or from the stainless Water-extracted PM samples were lyophilized and resuspended in steel balls used to size-fractionate the ROFA sample. sterile saline. The ICP results for the aerosolized PM2.5 cut fraction " Water used to extract filters. of WTC3 generally agree well with those determined by ‘ NIST Standard Reference Material 1649a (Washington DC TSP PM). XRF (Table 3). Calcium content of acid-extracted WTC3 Endotoxin levels measured as endotoxin units (EU) per ml water was somewhat lower by ICP (20-22%) than calcium extract. Samples were tested for inhibition of the endotoxin assay content of solid WTC3 by XRF (26.6%). This may reflect (none was detected). an incomplete extraction in the one hour timeframe of ' Average of 3-4 measurements.

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NYC-WTC_000149157