Following an environmental accident in a sulfuric acid production plant, a transversal study was made to investigate respiratory and irritative symptoms on the population. A questionnaire was applied to a simple random sample from people present until 900 meters from the plant by the time of the event, considering the winds' directions. The prevalence of symptoms and Chi-square test was made according to gradients of 300 meters. The density of symptoms per area, geo-referenced, was pondered. The Chi-square test was significant on the 451 people studied for all symptoms, except by wheezing, comparing gradients of distance. The grouped symptoms presented the following ODDS Ratio (OR): high respiratory (OR: 6.18; 2.10; 1.00); irritative (OR: 6.06; 2.09; 1.00); low respiratory (OR: 4.93; 2.08; 1.00); nausea and headache (OR: 4.66; 2.02; 1.00). The authors have found a major density of symptoms in the vicinities of the source. The study contributed to instigate mitigating measures in the company.
sulfuric acid; chemical accident; surveillance