Environmental odours and somatic complaints.

Two field studies in two cities in Northrhine-Westfalia were carried out in order to characterize the degree of association between environmental odour-exposure, annoyance, and somatic symptoms. In both studies, odour effects were assessed through personal interviews by means of standardised questionnaires. In the first study, the odour source was a fertilizer plant for mushroom cultivation with particularly offensive odour emissions. The distance from the source was taken to characterize the intensity of odour exposure. 250 subjects were interviewed at close, medium or remote distance from the plant. Apart from an extremely high degree of annoyance, an increasing frequency of somatic symptoms was found with increasing proximity to the odour source. Somatic symptoms were directly linked to odour exposure and additionally mediated by annoyance. In the second study (n = 322), the odour source was a pig rearing facility, and the degree of odour exposure was assessed by measuring the frequency of odour-events by means of systematic field observations. Results showed that the degree of odour-annoyance as well as the frequency of somatic symptoms increased significantly with increasing odour-exposure, although their frequency was reduced relative to the first study, and mediated by annoyance. In both studies, perceived negative health was associated with increased symptom reports, however, results for old age were inconsistent. Response tendencies and biases were controlled. Environmental odours have been shown to be associated with somatic symptoms and, may, thus, be considered as a risk factor for health and wellbeing of exposed populations, especially for vulnerable subjects with perceived negative health.