The IPCS collaborative study on neurobehavioral screening methods.

The International Programme on Chemical Safety sponsored a collaborative study to evaluate the utility of neurobehavioral test methods for identifying neurotoxic chemicals. The protocol consisted of a functional observational battery and automated assessment of motor activity. The study involved four laboratories in the United States and four in Europe, each of which evaluated the dose- and time-related effects of seven prototypic chemicals following both single and 4-week repeated exposures. The protocol was designed to assess the general utility and reliability of neurobehavioral screening procedures in a diversity of testing situations. The results of chemical testing indicated that all participating laboratories generally could detect and characterize the effects of known neurotoxicants, despite some differences on specific endpoints. These data provide important information regarding the reliability and sensitivity of neurobehavioral screening methods over a range of laboratory conditions. The purpose of this workshop was to describe the background and study design of the collaborative effort, present the data (including comparison of results across laboratories), and discuss issues regarding the conduct and interpretation of these behavioral tests, as well as future directions for neurotoxicity screening.