Clean Air and Biodiesel. More Important Than Ever This Earth Day

Posted on April 22nd, 2020

The world is facing a unique time in history on this Earth Day, a time of uncertainty and unknowns. However, there are a few things we can be certain of, we are in this together and biodiesel and renewable diesel play a significant role in clean air for our communities, which is more important than ever.

Many people think of the longer-term, big picture benefits of making more sustainable choices when they think of Earth Day. Big issues like global climate change, saving the rainforest, stopping industrial pollution — all valuable endeavors — but ones that are hard to wrap our minds around when facing the current COVID-19 pandemic. It is important to remember though, that many of those big efforts also improve the quality of the air we breathe.

Earth Day 2020

A Harvard University study recently concluded that long term exposure to air pollution leads to an increase in the COVID-19 mortality rate. Many pre-exiting conditions that increase the risk of death from COVID-19 are the same diseases that are affected by long-term exposure to air pollution.

Replacing fossil-fuel diesel with biodiesel drastically reduces harmful emissions from automotive exhaust. This includes reducing unburned hydrocarbons by 67%, reducing carbon monoxide by 48%, reducing polycyclic aromatic hydrocarbons by 80%, reducing nitrated polycyclic aromatic hydrocarbons (PAHs) by 90%, and reducing ozone potential of speciated hydrocarbons by 50%.1 The U.S. Environmental Protection Agency quantified these emission benefits of biodiesel in 2002.

New technology diesel engines have gotten a lot cleaner since then. The exhaust emissions of a diesel vehicle produced for model year 2010 and newer are so clean, in fact, that it is possible for those exhaust emissions to be cleaner than the ambient air on a summer day in a city like Los Angeles. There are still a lot of older vehicles in use, however. Factoring in the mix of older vehicles still on the road today, the nearly two billion gallons of biodiesel used in the U.S. last year to displace petroleum, reduced particulate matter (PM) emission by over six million pounds and reduced unburned hydrocarbons by nearly 7.5 million pounds.

Poor air quality effects human health in many ways. Nitrated polycyclic aromatic hydrocarbons (PAHs) have been identified as potential cancer-causing compounds. Particulate matter emission has been associated with 130,000 premature deaths annually in the U.S.2 Studies show that biodiesel reduces the formation of harmful smog by significantly reducing the hydrocarbons available to form ozone. Studies by the California Air Resources Board show that one premature death from respiratory illness can be prevented from every 10.5-ton reduction in particulate matter. Extrapolating these statistics on a national level would suggest that biodiesel use across the country prevented at least 293 premature deaths last year.

This is not something we take lightly. While data at hand does not cross reference exposure to at-risk persons, we can be confident that biodiesel is reducing emissions everywhere it is used. Lower emissions means at-risk persons may experience less chronic and acute bronchitis; reduced acute myocardial infarctions; reduced cardiovascular hospital admissions; reduced upper and lower respiratory symptoms; reduced exacerbation of asthma, and reduction in lost workdays, simply due to cleaner air.

Biodiesel is the first alternative fuel to successfully complete Tier I and Tier II health effects testing under the Clean Air Act. This included 90-day inhalation studies with biodiesel exhaust and concluded biodiesel is nontoxic and significantly safer than diesel exhaust.

Limited data has also shown that school children with asthma may benefit from biodiesel used in school buses, because it reduces harmful emissions in proximity to an at-risk population. The benefits of clean fuels have the most impact in urban areas where those reductions in harmful emission occur in proximity to impacted residents and other sources of air pollution.

Efforts to reduce air pollution are more valuable now than ever before. The wide-ranging impacts of COVID-19 have been devastating and well documented. On this Earth Day, let’s commit to clean fuels like biodiesel and renewable diesel that can help improve air quality here, now, while also bringing long-term benefits well into the future. Our cleaner fuel alternative may be a small piece of the overall puzzle, but it’s action we can take today.

1 USEPA; A Comprehensive Analysis of Biodiesel Impacts on Exhaust Emissions; 2002;

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