NYC Law Department letter regarding EPA draft report excerpts, July

NYC 9/11 Public Portal Document

Final Technical Report of the Public Health Investigation Page 37 of56 calcite, and portlandlte Increase the alkalinity of a fluid. Therefore, when these materials come Into contact with tissue, they can cause Irritation of skin and mucous membranes due to Increased alkalinity. Any anhydrous gypsum in settled dust would be hygroscopic, which would be drying and Irritating to the skin and eyes. Similarly, Inhaled material may Irritate or burn the respiratory tract (nose, throat, and lungs). The signs of an inflammatory response Include redness, swelling, heat, and pain. Reaction to a skin Irritant usually occurs at the point of contact between the skin and the substance. Eye irritants can cause redness, tearing, and Itching of the eyes. Respiratory irritants can affect the nose, throat, and lungs. They may cause an Itchy, watery nose, a scratchy or sore throat, coughing, chest tightness, wheezing, or difficulty breathing. All of these Irritant effects are generally temporary and will begin to resolve once exposures cease.

Occupational exposure guidelines (NIOSH) and standards (OSHA) for these minerals were developed to prevent these Irritant symptoms In most workers for a 40-hour workweek exposure (13,14,15). Although no guidelines or standards are available for skin contact or residential exposures, air exposure levels are established for both total and respirable minerals In air (see the following table). The airborne mineral levels measured In lower Manhattan are orders of magnitude below these occupational values. Although the occupational standards do not account for sensitive individuals or for extended periods of exposure, they provide a point of comparison. The levels of minerals seen In airborne dust of lower Manhattan are not at the levels known to be Irritating to healthy adult workers. However, It Is possible that sensitive Individuals may feel some Irritation. Additionally, direct contact with the dust-or shorter periods of higher air concentrations caused by disturbing the dust-may result In more Irritation than would be predicted by the reported airborne mineral levels.

Maximum Estimated NIOSH REL OSHA PEL Mineral Value In Lower (µg/m3) (µg/m3) Manhattan (ug/m 3) 10,000 (total) 15,000 (total) 141 (PMlOO) Gypsum 5,000 (resp) 5,000 (reso) 151 (PM4) 15,000 (total) 95J (PMlOO) Portlandlte 5,000 5,000 (reso) 84J (PM4) 10,000 (total) 15,000 (total) 14J (PMlOO) calcite 5,000 (reso) 5,000 (resp) 10J (PM 4) NIOSH = National Institute for 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.

http://www.atsd.r.cdc.gov/asbestos/lowermanhattan/ResSamp_Sep2002_Text.html 07/18/2003 NYC-WTC_000146697