mainly of hydrogenated terphenyl,[1] which is known to produce eye, skin, and respiratory irritation and possibly sensitization in experimental animals [Haley et al. 1959]. At the telephone company that reported the problem, workers exposed to CCP dust and vapors emitted from the paper experienced marked irritation at air concentrations exceeding 10 mg/m3 (data not given). Molhave and Grunnet [1981] believe that the terphenyls act as primary irritants, particularly when workers are wearing protective gloves that trap moisture and exposures next to the skin.
Göthe et al. 1981 and Norbiick et al. 1983b. Gothe et al. [1981] and Norback et al. [1983b] reported on an investigation of climatic and airborne concentrations of microcapsule solvents found in printing offices and ordinary offices that used the same type of CCP. The authors noted that very few complaints were related to CCP in the printing offices compared with ordinary offices. Temperature and relative humidity were, on the average, about the same in the two environments. The highest concentrations of microcapsule solvents were observed in the printing offices (Table 3-1). This finding suggests that no simple correlation exists between solvent vapor concentrations and the occurrence of complaints; or it may indicate that skin contact is the important factor.
Gockel et al. 1981. Gockel et al. [1981] reported on formaldehyde released to the air from CCP forms that were suspected of causing eye, skin, and respiratory irritation among office workers. Water extraction of CB white sheets of CCP yielded 0.18 to 1.89 mg formaldehyde per 8.5-×11-in. top sheet of CCP. The authors felt that water extraction might have enhanced the formaldehyde concentrations, so they adopted a sampling procedure that collected the formaldehyde released into 15 L of air (1 L/min for 15 min). Formaldehyde concentrations ranged from 33.6 to 858 μg/kg of forms sampled and from 0.02 to 0.96 ppm in the 15-L air samples using 8 different CCP forms. A modification of the procedure ensured adequate air flow past all parts of each form in the sampling apparatus. Standardized testing of four sheets of equivalent area for each type of five different forms resulted in formaldehyde concentrations ranging from 0.45 to 16.8 μg/kg, demonstrating a 37-fold difference in formaldehyde emissions. The authors demonstrated that these air sample analyses using a standardized testing area produced results that varied by a factor of 0.83 to 1.42 compared with sampling of a full form. The authors also provided evidence that the residual formaldehyde is dissipated into the air as a result of handling and storage. Air concentrations of formaldehyde were as high as 0.51 ppm in filing cabinet drawers where the forms had been separated and stored for more than 6 months.
Chrostek and Moshell 1982. See Section 4.2.1 for a description of this study.
Norbäck 1983b. Norback [1983b] studied the chemical emissions from entirely unused paper and from paper in which approximately 1% of the microcapsules had been crushed by standard writing. Most of the CCPs studied were handled by workers who had experienced work-related respiratory irritation symptoms when handling CCP. In light of the observed emissions of formaldehyde from CCP over time [Gockel et al. 1981], the 1- to 2-year-old paper was replaced with fresh CCPs of various types collected from three different printing shops. Most measurements were performed at an ambient temperature of 22 °C and 20% to 30% relative humidity. Several tests were also performed at 27 °C. CCP was cut, weighed, and measured for surface
- ↑ This description differs from other descriptions of Santosol components, which do not refer to terphenyls but to diphenylmethanes.
