Review: Endogenously Produced Volatiles for In Vitro Toxicity Testing Using Cell Lines.

Due to the ∼86,000 chemicals registered under the Toxic Substances Control Act and increasing ethical concerns regarding animal testing, it is not economically or technically feasible to screen every registered chemical for toxicity using animal-based toxicity assays. To address this challenge, regulatory agencies are investigating high-throughput screening in vitro methods to increase speed of toxicity testing, while reducing the overall cost. One approach for rapid toxicity testing currently being investigated is monitoring of volatile emissions produced by cell lines in culture. Such a metabolomics approach would measure gaseous emissions from a cell line and determine if such gaseous metabolites are altered upon exposure to a xenobiotic. Herein, we describe the history and rationale of monitoring endogenously produced volatiles for identification of pathologic conditions, as well as emerging applications in toxicity testing for such an approach.