Human behavioral toxicology. Central nervous effects of low-dose exposure to neurotoxic substances in the work environment.

The central nervous effects of low-dose exposure to the neurotoxic substances found in the work environment can manifest themselves both as adverse subjective reactions and as performance impairments and physiological changes. The acute manifestations of these effects can be studied under highly controlled conditions in laboratory experiments on volunteers or in quasi-experimental field studies on occupationally exposed workers. The effects of long-term occupational exposure are commonly studied with the use of epidemiologic techniques in cross-sectional investigations or cohort studies. In addition studies using data from clinical cases have been conducted to describe the chronic effects of exposure. Although these types of investigations can provide valuable information on the health hazards due to the neurotoxicity of different substances, their accomplishment encounters theoretical and practical problems, some of which are described and discussed in the present paper.