Self-reported symptoms and neuropsychological function among tunnel workers previously exposed to acrylamide and N-methylolacrylamide.

Objective: The aim of this study was to examine possible exposure-related symptoms and neuropsychological changes among tunnel workers previously exposed to grout containing acrylamide and N-methylolacrylamide.

Methods: In a cross sectional study, 44 male tunnel workers previously exposed to acrylamide and N-methylolacrylamide during grouting operations were exam-in-ed with neuropsychological tests, 2-10 years after last exposure. The control group consisted of 49 male tunnel workers with no history of acrylamide exposure. Questionnaires were used to assess retrospectively recalled symptoms during work and current symptoms at the time of the examination.

Results: The prevalence of paresthesia in hands and legs, and leg cramps during work peri-ods were higher in the exposed than control group. Self-reported prevalence of skin irritation, peeling of skin on the hands, white-finger attacks, headache, and breathlessness was also higher among the exposed workers. The Q-16 questionnaire on current symptoms indicated higher symptom prevalence among the exposed of impaired memory and concentration, emotional change, sleep disturbances, tiredness, headache, and sensory or motor changes. In contrast, no association was found between neuropsychological test results and acrylamide exposure, adjusting for relevant confounders. However, selected motor symptoms were associated with the corresponding results on tests for motor function.

Conclusions: Despite higher prevalences of self-reported current symptoms among the acrylamide-exposed compared to the control group, we did not find an association between occupational acrylamide exposure and health out-comes as measured by the chosen neuropsychological tests. Observed associations between chemical exposure and self-reported symptoms should be interpreted with great caution.