HAZARDOUS CHEMICALS - PSYCHOLOGICAL DIMENSIONS OF THE HEALTH SEQUELAEOF A COMMUNITY EXPOSURE IN TEXAS

Study objective - A chemical spill from an oil refinery exposed the lo cal community to more than 40 000 lb of highly toxic and corrosive hyd rofluoric acid. A community based symptom prevalence study found an as sociation between exposure and physical symptoms: the psychological im pact of the disaster and its potential effect on the reporting of phys ical symptoms is examined here. Design - The study used a population b ased survey design consisting of two phases: phase I, the exposure pha se, and, phase II, the symptom prevalence phase.Subjects - In phase I, information indicative of exposure was collected on 10 811 individual s in a door to door survey of a geographically defined area. In phase II, symptom prevalence information was gathered through in-person inte rviews with 2509 subjects selected from the phase I census in a sampli ng scheme that balanced across the exposure categories with regard to age, gender, and predisposition. The refusal rate in both phases was < 5%. Measurement and main results - Stepwise logistic regression analys es were used to assess the relative predictive importance of psycholog ical variables and hydrofluoric acid exposure in explaining the report ed physical symptoms two years after the disaster. The findings show a linear relationship between the level of hydrofluoric acid exposure a nd the degree of psychological stress two years after the accident. Hi gh exposure had a long term (more than two years) impact on physical h ealth for some self reported symptoms, even after controlling for the psychological impact. Some physical symptom reports, however, were bet ter explained by psychological status than by exposure to hydrofluoric acid. The physical symptoms for which exposure was the major predicto r were those for which the biological plausibility of a relationship w ith hydrofluoric acid exposure was direct. Conclusions - Measures of p sychological status should be included in symptom studies of health se quelae to man-made disasters so that the physical effects of exposure can be more accurately assessed.