EPA Misses Historic Opportunity to Reduce Wood Smoke Pollution
Image: U.S. EPA
On February 7, following a multi-year process, the U.S. Environmental Protection Agency announced an update of the National Ambient Air Quality Standards for Particulate Matter. These standards set the maximum allowable levels of fine particulate matter (PM2.5).
Scientists acknowledge that PM2.5 is one of the most hazardous of all air pollutants, and the standards are meant to protect the public by ensuring air pollution is kept below levels that are known to harm health. Under the Clean Air Act, the EPA is supposed to review, and revise if necessary, the standards every five years based on current scientific evidence.
First for the good news: the EPA announced it is planning to lower the annual PM2.5 standard from 12 μg/m3 (micrograms per cubic meter) to 9 μg/m3.
However.
There are actually two PM2.5 standards. The second (and arguably more important standard) is measured over a 24-hour period. The 24-hour standard hasn’t been changed since 2006, the year the Dow Jones Index first crossed 12,000 (it’s now above 38,000). Since then, there has been a deluge of scientific evidence linking PM2.5, even at extremely low levels, to serious health problems and premature death.
Last year, thousands of people and organizations, including ours, submitted comments to the EPA urging them to lower the 24-hour PM2.5 standard. We pointed out in our submission that lowering the 24-hour standard was critical for protecting public health from wood smoke pollution.
During the rule-making process, the EPA acknowledged that the 24-hour standard is the more important one in communities affected by wood smoke pollution. They noted that in areas affected by localized sources of pollution, including wood burning, that the “24-hour standard is generally the controlling standard,” meaning it is the more relevant one for protecting air quality.
The majority of the EPA’s own Clean Air Scientific Advisory Committee (CASAC) recommended lowering the 24-hour standard. They specifically expressed concern that the annual standard did not protect people in areas affected by wood smoke pollution.
So how did the EPA respond?
By deciding to leave the 24-hour standard unchanged at a whopping 35 μg/m3, the same level that was set back in 2006.
To put that in perspective, the World Health Organization recommends a 24-hour standard of 15 μg/m3.
This is not good news for the significant numbers of Americans affected by pollution from wood burning.
According to the EPA’s own National Emission Inventory, more PM2.5 pollution in the U.S. comes from wood burning than from motor vehicles or from industrial processes. Wood burning is the largest source of PM2.5 pollution in many communities, such as the San Francisco Bay Area.
During the 18 long years since the 24-hour PM2.5 standard was last updated, the scientific evidence of harms from PM2.5 has only grown stronger. Will we have to wait another 18 years before the EPA finally lowers the 24-hour PM2.5 standard?
And more importantly: how many people will needlessly suffer or die from wood smoke pollution in the meantime?
