Contact Dermatitis in California Nursery Workers: Part II. Pilot Field Study

Among the subgroups of agricultural workers, nursery workers have previously been identified as a group at high risk for occupational skin disease. Review of available surveillance information on nursery skin illnesses has also demonstrated that provocation patch testing is performed in less than 1% of the reported cases. We tested reactions to a battery of pesticides, plants, and the standard European patch antigens among a sample of nursery workers. From a pool of 896 workers’ compensation records (441 skin and 455 non-skin (eye, systemic/respiratory or musculoskeletal)) injuries or illnesses, 467 (52.1%) were contacted by mail and 349 (38.9%) had valid addresses or phone numbers. Of this group 29 workers (8.3%) agreed to participate. Eleven additional subjects were identified from among their coworkers, and one agricultural extension specialist who worked extensively in the nursery industry also participated. Demographically participants and non-participants were similar, but we could not ascertain whether they were similar or dissimilar with regard to history of skin disease. In the 39 subjects who underwent testing to the complete battery of plant, pesticide, and standard series antigens, we observed reactions to one or more test substances in 18 (46.2%). This included 8 subjects (20.5%) reacting to either nickel, chromium, fragrance mix, wool, or thiuram (an ingredient in many rubber formulations that is also used as a fungicide) in the standard environmental antigen series, 5 (12.2%) reacting to either carnations or primrose in the plant series, and 10 (25.6%) reacting to either sulfur, PCNB, captafol, difolatan or chlorpyrifos in the pesticide series. Reactions to pesticides and to sulfur, in particular, appeared to be correlated with a history of mixing, loading, or applying pesticides. Because the study was hampered by a low participation rate, the findings can not appropriately be generalized to the entire population of interest. However, the reactions to sulfur, PCNB, chlorpyrifos, and to carnation extracts were unexpected based upon prior published literature and deserve additional study.