Studying Symptoms and Risk Perception in a Contaminated Site: A Valuable Connection

Abstract: Long-term exposures to air pollution have shown increased risks of developing chronic respiratory diseases, and short-term exposures have been associated with excesses of bronchitis, asthma and respiratory symptoms. A Health Impact Assessment process carried out in the Valley of Agri River (Basilicata, Italy) where is located a crude oil treatment plant, included a population cohort study, a sample study to assess respiratory function and symptoms and risk perception. The main pollutants emitted are NOx, H2S and VOCs, particularly non-methane hydrocarbons. On 6,795 residents, a sample of 200 healthy subjects, aged 18-74 years, was randomly selected, stratifying by gender, age group and home address in two areas: proximal or distal. For each subject, a spirometry test was performed and a questionnaire administered for characterizing anamnesthic hystory, respiratory symptoms, socio-economic data and risk perception. Measured functional parameters and declared respiratory symptoms were compared between the two areas by using a multivariate logistic regression, adjusted for BMI, smoking, occupational exposure, cardio-vascular comorbidity. Nine subjects showed a bronchial obstruction after bronco-dilator testing. For most of the symptoms a higher risk in the proximal aerea emerged: for cough outside the common colds for some periods of the year and respiratory allergic symptoms associated with eye symptoms, it was statistically significant (OR 2.46 IC95 % 1.02-6.11; OR 2.53 CI95% 1.29-4.94). Risk perception was the same among the subjects residing in the two areas: high perception of exposure to air pollution or to develop asthma was declared in 38% and 67% respectively. Although the small sample size, the excesses of risk emerged for some respiratory symptoms, for which a bias due to risk perception can be ruled out, represent an important result to be used to improve the environment and health sustainability through the implementation of an ad hoc surveillance system.