Non-specific symptoms in response to hazard exposure in the workplace.

Recent concerns in occupational health have shown a shift in emphasis from the study of diseases with well-established pathology toward the investigation of conditions characterized by a range of nonspecific symptoms. Exposure to potential hazards differing widely in terms of their physical nature or chemical composition, for example, electromagnetic fields, organophosphate-based pesticides, and organic solvents, frequently results in the reporting of a relatively consistent group of symptoms. Furthermore, these symptoms may arise among groups of workers where no specific physical or chemical cause can be implicated; for example, in many cases of sick building syndrome. The role of psychosocial factors in the expression of ill-health has been well-documented in the psychological literature. Important modifying factors include the attitudes and belief systems of the individuals concerned, certain personality and behavior patterns, and the presence of current stress or pre-existing psychological distress. In addition, social processes may be involved in the generation and reinforcement of health concerns at the group level. These include the workers' perceptions of the competence and credibility of managers and professionals, and the influence and involvement of the media, pressure groups, and the legal system. A proper understanding of the association between putative hazards and the reporting of nonspecific symptoms therefore requires consideration not only of the direct physical pathway between hazard and harm, but also an assessment of factors which may modify the relationship between exposure and symptom reporting. The results of such investigations have important implications for determining the focus of any management and control strategies which may subsequently be implemented in the workplace.