NYC-WTC_000232959

NYC 9/11 Public Portal Document

2. Soluble Minerals: Gypsum, Portlandite, and Calcite Although possible skin, eye, The potential health effects of gypsum (hydrated calcium sulfate), and respiratory tract irritants, portlandite (calcium hydroxide), and calcite (calcium carbonate) the soluble minerals gypsum, are similar as these minerals are similar chemically and portlandite, and calcite do not physically. All three minerals are crystalline in Io rm and soluble pose any hazard for long-term (11,12). Because these minerals are soluble in health effects. body fluid, they are easily cleared from the respiratory tract and lungs when inhaled (13,14,15). Therefore, no long-term respiratory effects have been observed, even at the very high exposures that occur during the mining and processing of these minerals (16,17).

Calcite, and portlandite 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 imtating to the skin and eyes. Similarly, inhaled material may irritate or bum 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.

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