THE IPCS COLLABORATIVE STUDY ON NEUROBEHAVIORAL SCREENING METHODS - V- RESULTS OF CHEMICAL-TESTING

The IPCS Collaborative Study on Neurobehavioral Screening Methods was undertaken to determine the intra-and inter-laboratory reliability of a functional observational battery (FOE) and an automated assessment o f motor activity in eight laboratories world-wide. Following the train ing phase and the conduct of proficiency studies in all laboratories, participants proceeded to test the effects of seven chemicals in both single dose and four-week repeated dosing scenarios. The chemicals stu died were acrylamide, bisacrylamide, p,p'-DDT, lead acetate, parathion , toluene, and triethyl tin. Participants received coded samples from a common source. In order to judge the general utility of these proced ures in a diversity of testing situations, laboratories conducted the studies under their standard conditions, using their choice of rat str ain and test equipment Chemical doses and time of peak effect for acut e testing were determined by each laboratory: these parameters were gu ile similar for some chemicals, but varied greatly for others. The res ults of the chemical tests indicated that while there was some variabi lity in the data on specific endpoints, all laboratories detected and characterized the effects of all but one of the known neurotoxicants. The one exception (toluene) was probably due to other factors (e.g., d ose level, route of administration) rather than lack of sensitivity of the test methods. This study provides extensive data regarding the us e of neurobehavioral screening methods over a range of laboratory cond itions as well as the reliability, sensitivity, and robustness of the tests to detect neurotoxic potential of chemicals. (C) 1997 Intox Pres s, Inc.