The Impact of Biodiesel on Pollutant Emissions and Public Health

Abstract

An overview of recent studies of the impact of biodiesel and biodiesel blends on air pollutant emissions and health effects is provided. Biodiesel blends of 20% produce reductions of 15% or higher (depending upon engine model and test cycle) in emissions of particulate matter, carbon monoxide, total hydrocarbons, and a group of toxic compounds including vapor-phase hydrocarbons from C 1 to C 12 , aldehydes and ketones up to C 8 , and selected semivolatile and particle-phase PAH and NPAH. Based on the studies reviewed and recently acquired data, individual engines may show oxides of nitrogen increasing or decreasing, but on average there appears to be no net effect for blends of 20% biodiesel-the most common biodiesel blend. Exhaust from a diesel engine operating on 100% biodiesel was also shown to have only modest adverse effects in an animal exposure study. Studies of the impact of biodiesel on particle size have not produced consistent results and additional research in this area is needed. Biodiesel is also shown to significantly reduce life-cycle greenhouse gas emissions in comparison to petroleum diesel.

Oxidative Stress, Inflammatory Biomarkers, and Toxicity in Mouse Lung and Liver after Inhalation Exposure to 100% Biodiesel or Petroleum Diesel Emissions

“…BD derived from soy-bean vegetable oil is largely composed of fatty acid derivatives (e.g., methyl linoleate; see Supplemental Material, Table S1), and its combustion products may include high levels of unsaturated aldehydes compared to neat D. The unsaturated sites, serving as major targets of lipid peroxidation, may result in formation of both oxidized and unsaturated aldehydes (Fullana et al, 2004;Da Silva and Pereira, 2008;Seaman et al, 2009). Such organic derivatives were found to exert higher toxicity than the solid PM fractions (McCormick, 2007). Recent studies reported that exposure to neat BD CE was more toxic than D, producing cardiovascular alterations as well as systemic and pulmonary inflammation in mice (Brito et al, 2010;Yanamala et al, 2013).…”

“…Author Manuscript air pollutants (including PM and CO) and greenhouse gas emissions (e.g., B20 reduces CO by 15%) (McCormick, 2007;Rakopoulos et al, 2008;Ramadhas et al, 2004; U.S. EPA, 2002).…”

“…BD, produced from non-petroleum-based renewable resources, is believed to be safe and biodegradable and can be used in most diesel engines. As compared to traditional petroleum-based diesel (D), combustion of BD results in the reduction of some air pollutants (including PM and CO) and greenhouse gas emissions (e.g., B20 reduces CO by 15%) (McCormick, 2007;Rakopoulos et al, 2008;Ramadhas et al, 2004;U.S. EPA, 2002).…”

“…The semivolatile derivatives from BD emission products were found to have higher toxicity than solid PM (McCormick, 2007). While several studies demonstrated the potential of neat BD (B100) and its blends to reduce exposure of underground miners to elemental carbon and PM (Bugarski et al, 2006), overall pulmonary toxicity of BD exposure has not been sufficiently addressed.…”

Aerosols Emitted in Underground Mine Air by Diesel Engine Fueled with Biodiesel

“…[15][16][17] An increase in concentrations of smaller particles 15 and nucleation aerosols 16,17 and a reduction in concentrations of accumulation-mode aerosols 16,17 were reported. Research on the impact of biodiesel on particle size has not produced consistent results 18 and additional research in this area is needed. Swanson and coauthors 19 concluded that the speculative nature of a reduction in health effects based on chemical composition of biodiesel exhaust needs to be followed up with investigation in biologic systems.…”