Neurobehavioral Evaluation in Humans Exposed to Hydrocarbons: A New Statistical Approach

Abstract

Background: Epidemiological researches showed a significant increase in the alterations of the cognitive and emotional sphere in subjects exposed to hydrocarbons. This paper deals with a study carried out on a group of male workers between the ages of 35 and 40, who had been working as external workers in a large refinery. Methods: All the subjects worked in short shift rotation and were exposed to hydrocarbons during the loading of tank trucks. The response data reported by this investigation are compared to data of different male subjects who had also been working at the refinery for the same period of time, but as administrative day workers, and were certainly not exposed to the hydrocarbons. The nonparametric statistical analysis was carried out by a new nonparametric approach based on multivariate permutation tests. Results: Results show a significant difference in the response to neurobehavioral tests. The exposed group showed behavioral tendencies towards anxiety and depression that the nonexposed group did not. Conclusions: The study shows that occupational exposure to hydrocarbons is associated with neurobehavioral modifications, and that the use of psychometric tests can be useful for monitoring the psychosomatic consequences by exposure to hydrocarbon microdoses.