VOC sampling locations table for Ground Zero area, Jan 2002

NYC 9/11 Public Portal Document

IV.b.2. Chromium and Nickel Chromium and nickel were chosen for evaluation in this assessment because both can be irritating and sensitizing. Chromium and nickel are used in the production of stainless steel and other metal alloys. Chromium, in the hexavalent form, Cr^, can damage the nose and cause cancer. Similarly, workers who have breathed large amounts of nickel have developed lung and nasal sinus cancers. Total chromium in urban air typically ranges from 0.01 to 0.03 pg/m’ (ATSDR, 2000c), and nickel concentrations in urban air range from 0.001 to 0.328 pg/W (ATSDR, 1997b).

To evaluate chromium and nickel, the OSHA PELs (chromium, 1 mg/m^; nickel, 1 mg/m^) were used as a screening benchmark (NIOSH, 2002). For chromium, the ATSDR intermediate inhalation MRL for Cr'’ PM (1.0 pg/m’) was also used (ATSDR, 2000c). For this evaluation, it was assumed that chromium would be released as solid PM, not as a mist, in order to compare measurements with the ATSDR MRL, which is specific to PM concentrations.

Data for evaluating chromium and nickel came mostly from the EPA WTC monitoring database. A total of 21 air samples, collected between September 23 and January 31 at Building 5, were evaluated for chromium and nickel at Ground Zero. None of the samples evaluated exceeded a screening benchmark for either chromium or nickel, nor did any values detected by ORD monitoring on the Ground Zero perimeter (Figure 18) exceed any benchmark values for chromium or nickel. On the basis of the results reported, chromium and nickel releases would not have been expected to cause any adverse health effects within Ground Zero.

Approximately 512 monitoring samples collected at sites surrounding Ground Zero were evaluated for chromium, including 86 samples taken at the Staten Island landfill and 16 samples from personal air monitors worn by NYC fire department personnel. Approximately 637 monitoring samples collected at sites surrounding Groimd Zero were evaluated for nickel, including 86 samples taken at the Staten Island landfill. Samples were collected between September 23 and January 31. None of the samples evaluated for either chromium or nickel exceeded a screening benchmark. On the basis of the samples collected, chromium and nickel releases would not have been expected to cause any adverse health effects at sites surrounding Ground Zero.

Like most contaminants, however, elevations in chromium were seen in concentrations measured near Ground Zero, and near September 11 in time. At the Ground Zero monitoring, WTC building 5, chromium was not detected in four samples from September 23 to October 8, but then it was detected at 0.24 and 0.38 pg/m’ on October 11 and October 15. Further sampling at Ground Zero through February of 2002 showed mostly non-detects (9 samples) and samples near typical background for chromium (4 samples between 0.02 and 0.07 pg/m’), except for one higher reading at 0.22 pg/m’ in January, 2002. Chromium sampling at all other sites around Groimd Zero showed the same trend: elevations above typical urban background through about mid-October, with measurements then dropping to typical urban background (with a spike in January, which may or may not be due to Ground Zero emissions) through the sampling in February of 2002.

Unlike chromium, nickel was not found elevated above background at any time or location

DRAFT-DO NOT QUOTE OR CITE 64 October 2002

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