Diagnostic and exposure criteria for occupational diseases

The diagnosis of occupational diseases is based, similarly to any group of diseases caused by exogenous agents, on two components: the identification of the disease affecting the subject (1), and the evaluation of the subsistence of a causal association between the observed disease and a defined occupational exposure (2). A second very important aspect of any environmental-related disease is its preventability, and prevention largely relies on the knowledge of the relationship between exposure and its effects. A third key-aspect is that any occupational disease claims a compensation. Finally, occupational diseases should be properly reported and recorded, in order to collect necessary information to define the burden of disease attributable to specific risk factors, to point out new and emerging risk factors and diseases and to promote preventive interventions. These strongly related components find a fundamental support from the lists of occupational diseases adopted at different levels. Of course, at the basis of the definition of any list of occupational diseases there is the need of reaching an agreement on the criteria for the diagnosis, necessary to ensure consistency in the clinical decisions, to contribute to the management of individual cases and to promote preventive interventions. In substance, in any occupational disease the clinical features must fit in with the current knowledge on the effects consequent to a specific exposure, and exposure levels should be adequate to cause the effect (intensity per duration) as well as the minimum induction time. Finally, the latency period (time elapsed from the beginning of the exposure and onset of the effect) must be consistent with the current knowledge. A very critical issue present in any list addressed both at compensation and at prevention is that the levels of certainty necessary for prevention are significantly lower (precautionary principle) that those necessary to reach a clinical diagnosis.