Biodiesel Exhaust: The Need for Health Effects Research

BACKGROUND: Biodiesel is a diesel fuel alternative that has shown potential of becoming a commercially accepted part of the United States’ energy infrastructure. In November 2004, the signing of the Jobs Creation Bill HR 4520 marked an important turning point for the future production of biodiesel in the United States because it offers a federal excise tax credit. By the end of 2005, industry production was 75 million gallons, a 300% increase in 1 year. Current industry capacity, however, stands at just over 300 million gallons/year, and current expansion and new plant construction could double the industry’s capacity within a few years. Biodiesel exhaust emission has been extensively characterized under field and laboratory conditions, but there have been limited cytotoxicity and mutagenicity studies on the effects of biodiesel exhaust in biologic systems. OBJECTIVES: We reviewed pertinent medical literature and addressed recommendations on testing specific research needs in the field of biodiesel toxicity. DISCUSSION: Employment of biodiesel fuel is favorably viewed, and there are suggestions that its exhaust emissions are less likely to present any risk to human health relative to petroleum diesel emissions. CONCLUSION: The speculative nature of a reduction in health effects based on chemical composition of biodiesel exhaust needs to be followed up with investigations in biologic systems.