A Neurofunctional Test Battery for Evaluating the Effects of Long-term Exposure to Chemicals

In order to determine the neurotoxic potential of long-term chemical exposures, a battery of tests was developed to evaluate changes in spontaneous activity, grip strength, coordinated movement, two-choice visual discrimination performance, and peripheral nerve conduction velocity in the rat. To evaluate the reliability and sensitivity of these tests, experiments examining the effects of acrylamide on measures of motor and peripheral nerve function were conducted. In addition, the use of discretetrial discrimination procedures to assess changes in learned performance was also examined in experiments with styrene and n-hexane. Results with acrylamide indicated that tests of peripheral and motor function were capable of detecting and describing the progressive development of peripheral nervous system effects. Further, studies with styrene and n-hexane demonstrated the sensitivity of discrete-trial techniques to both the acute and chronic effects of solvent exposure. Taken together, these studies demonstrate the applicability of neurofunctional measurements to chronic exposure studies for determining the range, time course, and severity of chemically induced nervous system effects. The differences in profiles of neurotoxic effects produced by different chemicals emphasize the need for a battery of tests to fully describe the range of functional effects produced by chemical exposures.