NYC 9/11 Public Portal Document
health concern in the form of eye, nose and throat irritation, persisting adverse heath effects
would not be anticipated, unless these minerals remained suspended in high concentrations.
Indoor and street-level outdoor air sampling done in November and December of 2001 show that
the levels of these chemicals, over a time-weighted sample, were below levels associated with
irritant effects (See Table 1). Although there are methodological difficulties in quantifying these
materials by X-ray Diffraction (XRD) techniques, a semi-quantitative screening of the results
showed that the air levels were orders of magnitude below occupational standards for irritant
effects. However, since the presence of minerals in settled dust indicates there is potential for the
materials to be resuspended, these minerals should be evaluated qualitatively. Therefore,
although no screening levels are developed for these minerals as COPCs, the Pilot Cleaning
Effectiveness Initiative mentioned in the Introduction will report qualitatively on the presence of
gypsum, calcite and portlandite, while the quantitative analyses for crs^stalline silica (a COPC
discussed above) are being performed by XRD (following MOSH Method 7500).
Table 1. Index of NIOSH and OSHA exposure limits and estimated maximum values in Lower
Manhattan.
*Maximum Estimated
NIOSH REL
Mineral OSHA PEL (ug/m^) Value (J) in Lower
(ug/m’)
Manhattan (ug/m^)
10,000 ug/m^ (total) 15,000 ug/m^ (total) 14J(PM100)
Gypsum
5,000 (ug/m’ resp) 5,000 (resp) 15J(PM4)
15,000 ug/m^ (total) 95J(PM100)
Portlandite 5,000 ug/m’
5,000 ug/n? (resp) 84J (PM4)
10,000 ug/n? (total) 15,000 ug/m^ (total) 14J(PM100)
Calcite
5,000 ug/m^ (resp) 5,000 ug/m’ (resp) 10J(PM 4)
NIOSH = National Institute of Occupational Safety and Health, Centers for Disease
Control and Prevention
REL = recommended exposure level/limit
OSHA = Occupational Safety and Health Administration
PEL = permissible exposure limit.
resp = respirable
* [NYCDOH, 20021
Other Substances that Were not Selected to be COPCs
The following summary is provided for substances that were investigated, but not included on
the COPC list. A full discussion of the reasons is provided in Appendix A.
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