FOOD-AND-DRUG-ADMINISTRATION PROPOSED GUIDELINES FOR NEUROTOXICOLOGICAL TESTING OF FOOD CHEMICALS

The fact that some chemicals may adversely affect the nervous system i s certainly not a new concept in regulatory toxicology. In 1982, the F DA issued testing guidelines for the safety evaluation of proposed dir ect food and color additives wh ich included the assessment of nervous system toxicity as part of the genera ! toxicological profile. Howeve r, these guidelines provide only broad and nonspecific recommendations as to how this assessment may best be carried out. The information de rived from toxicity screening studies conducted according to these gui delines enable little more than the detection of clearly evident adult nervous system toxicity associated with general neuropathology and ov ert neurological dysfunction. Little consistent or systematically docu mented information is typically developed about other equally importan t types of neurotoxic effects including, for example, behavioral dysfu nction and developmental neurotoxicity. Concerns about these more subt le types of neurotoxic effects have become a prominent public health i ssue and have resulted in demands for an increasing level of assurance that efforts are being made to minimize even further the risks of neu rotoxicity from human exposure to chemical substances. In an effort to address these concerns, the FDA is including specific attention to ne urotoxicity in a proposed revision of its toxicity testing guidelines for food additives. These proposed guidelines focus on a more careful evaluation of structural and functional measures of neurotoxicity as a routine component of safety assessment. This focus will enable the de velopment of the type of information needed for a more effective asses sment of the full spectrum of neurotoxic hazards. The revised guidelin es for neurotoxicity testing will be discussed in terms of the FDA's o verall approach to safety assessment. (C) 1996 Intox Press, Inc.