symptoms reported by the exposed and comparison workers during the second exposure period, which involved processing forms that were several months old. Exposed workers reported large decreases in most symptoms during the second period, when they handled the completed forms with broken microcapsules (280/day) rather than the fresh forms (1,200 per day) during the first period. These symptom decreases during the second period included a sixfold decrease in skin irritation and threefold decreases in eye irritation, pruritus, nasal congestion, nose-bleed, and cough. However, increases occurred in facial erythema, rash, and runny nose.
Figure 4-2 shows the relationship between pruritus and increasing CCP exposure. Four of the 18 comparison workers (22.2%) during the first exposure period and 3 of the 16 comparison workers (18.8%) during the second exposure period reported pruritus. Ten of the 20 workers (50%) exposed to CCP experienced pruritus: 4 of 10 employees (40%) who worked daily with 101 to 750 form sets, and 6 of 10 employees (60%) who worked with >750 form sets reported pruritus. These results show a statistically significant increase in the prevalence of pruritus with increasing exposure to CCP, regardless of whether the responses were used from the first exposure period (P=0.049) or the second exposure period (P=0.03). Clinical examination revealed no significant differences between atopic workers in the exposed and comparison groups. The duration of pruritus after histamine provocation was also the same in both groups. Erythema index measurements showed large variations, and no significant differences existed between the reactions of workers in the exposed and the comparison groups to contact with paper, CCP, the contents of the microcapsules, or a damping solution from CCP. Scratch tests with CCP were negative, and skin patch tests with nickel yielded four reactions in the exposed group and one reaction in the comparison group. Although these differences were not statistically
Figure 4-2. Prevalence of pruritus among CCP handlers by sheets of CCP handled during the exposure period.
