Objectives: The main aim of the study was to examine possible solvent-associated effects on the nervous system in currently employed painters. Special attention was paid to evaluate subtle health effects.
Materials and methods: A total of 401 painters and 209 construction workers without solvent exposure with at least 10 years of professional experience were subjected to a clinical, neurological, psychiatric, neuropsychological and neurophysiological examination. For personal medical and occupational history, standardized questionnaires were used. A quantitative rating of exposure was obtained by expert rating of the respective occupational history without knowledge of the individual test results.
Results: There was no excess of somatic disorders or solvent-associated adverse effects on the nervous system. No distinct effects of solvent exposure on nerve conduction velocities (NCV) or cognition were found. Discrete NCV deficits in painters were not considered a sign of subclinical polyneuropathy. Painters, however, reported an excess of specific symptoms that could be assigned to "mood and behaviour". The differences between specific and non-specific questionnaire outcomes on the one hand and the positive correlation between chronic exposure index and symptom scores on the other hand support the hypothesis of solvent-induced effects. Because data is lacking on past solvent exposure, it is not possible to relate these effects to current exposure limits.
Conclusions: Currently employed painters differ from controls not exposed to solvents with respect to the frequency of certain symptoms in mood and behaviour. These symptoms are related to life-long solvent exposure rather than to current exposure. At present, the issue of time course and reversibility or irreversibility of these symptoms cannot be answered. The predictive value for subsequent neuropsychiatric morbidity remains to be elucidated in follow-up studies.