Report of the Institute's Health Research Committee. This report summarizes what emissions-related health problems, if any, would emerge if methanol were to become more widely used as an automotive fuel. Methanol-fueled vehicles emit both formaldehyde and methanol vapors. in 1985, HEI started a research program to investigate the potential health effects of aldehydes, including formaldehyde. Before proceeding with research on methanol vapors, the HEI Health Research Committee decided to undertake additional analysis. This Special Report focuses on the potential exposure of the general public to methanol vapor that might result from an introduction of methanol-powered vehicles in the general fleet. The report also evaluates the likely health implications of such exposure.