The LD50 test and in vitro toxicology strategies.

In order for in vitro alternatives for acute toxicity testing to emerge, it will be necessary to stage a clearly-defined strategy. The strategy, with its intermediate objectives and proximal decision points, could serve as the basis for validation of the in vitro tests to be used as components of a test battery for assessment of general cytotoxicity and for the evaluation of impairment of differentiated function. An approach for the evaluation of potential neurotoxic agents is presented and could serve as a model for the evaluation of potential ocular, hepatic, and other toxins.