Human neurobehavioral toxicology testing: current perspectives.

Standardized tests or test batteries for neurotoxic effects are needed for premarket testing of chemicals (and related regulatory needs) and for the development of a neurotoxicity data base. Three widely known human test batteries based on past research findings and developed to screen for a broad range of neurotoxic effects are currently in use. One was developed by Finland's Institute of Occupational Health, one was recently recommended by the World Health Organization, and one was recently developed as a computer-implemented battery by US researchers. Each of these batteries assesses many frequently occurring neurotoxic effects, but each is limited by the lack of tests for some motor and sensory functions and affective responses that often occur following chemical exposures. Problems with field or worksite assessments using these test batteries involve age, education, socioeconomic, and job differences between exposed and comparison groups, and the lack of normative data on these batteries. To address some of these problems, the human neurobehavioral test batteries are currently undergoing reliability or validity assessments on a national and international scale. This will provide an assessment of their utility and accelerate development of a data base of neurotoxic effects of chemicals.