The U.S. Environmental Protection Agency (EPA) has strengthened the National Ambient Air Quality Standards (NAAQS) for ground-level ozone to 70 parts per billion (ppb) from 75 ppb to protect public health, EPA Administration Gina McCarthy announced Oct. 1.
The updated standards will reduce Americans’ exposure to ozone, improving public health protection, particularly for at risk groups including children, older adults, and people of all ages who have lung diseases such as asthma, McCarthy said.
EPA noted that ground-level ozone forms when nitrogen oxides (NOx) and volatile organic compounds (VOCs) react in the air.
EPA examined nearly 2,300 studies in this review of the ozone standards including more than 1,000 new studies published since the last review of the standards in 2008. Scientific evidence shows that ozone can cause a number of harmful effects on the respiratory system.
The public health benefits of the updated standards, estimated at $2.9bn to $5.9bn annually in 2025, outweigh the estimated annual costs of $1.4bn, EPA said.
Local communities, states, and the federal government have made substantial progress in reducing ground-level ozone. Nationally, from 1980 to 2014, average ozone levels have fallen 33%, while the economy has continued to grow. And by 2025, EPA projects that existing rules and programs will bring the vast majority of the remaining counties into compliance. Advances in pollution control technology for vehicles and industry along with other emission reduction standards, including “Tier 3” clean vehicle and fuels standards, the Clean Power Plan and the Mercury and Air Toxics Standards, will significantly cut smog-forming emissions, helping states meet today’s updated ozone standards, EPA said.
To ensure that people are alerted when ozone reaches unhealthy levels, EPA is extending the ozone monitoring season for 32 states and the District of Columbia. This is particularly important for at-risk groups, including children and people with asthma because it will provide information so families can take steps to protect their health on smoggy days.
EPA also is strengthening the “secondary ozone standard” to 70 ppb, which will improve protection for trees, plants and ecosystems. New studies since the last review of the standards add to evidence showing that repeated exposure to ozone reduces growth and has other harmful effects on plants and trees. These types of effects have the potential to harm ecosystems and the benefits they provide.
The Clean Air Act provides states with time to meet the standards. Depending on the severity of their ozone problem, areas would have until between 2020 and 2037 to meet the standards.
“Put simply – ozone pollution means it hurts to breathe for those most vulnerable: our kids, our elderly and those suffering from heart and lung ailments,” said EPA’s McCarthy. “Our job is to set science-backed standards that protect the health of the American people. Today’s action is one of the most important measures we can take for improving public health, reducing the costs of illness and protecting our children’s health,” she added.
McCarthy says EPA must update rule regularly
During a conference call with reporters, McCarthy said children are at risk to ozone pollution because they spend more time outside than adults, “or at least we hope they do.”
While Los Angeles is no longer as smoggy as years ago, “science tells us that ozone is still making people sick,” McCarthy said. She also noted that EPA is required to review ozone standards every five years under Clean Air Act. Millions of Americans currently live in counties that are not in attainment, McCarthy said.
Industry has recently undertaken a high-profile media campaign saying that current standards are working and not in need of revision.
In response to a question, McCarthy said EPA expects that only 14 counties outside of California would actually be out-of-attainment in 2025.
One questioner noted that President Obama’s previous EPA Administrator Lisa Jackson had initially proposed a more stringent. “There is a lot more health data available today than Lisa [Jackson] had available,” McCarthy said. There is “very definitive” data calling for regulation of ozone at this level.
“It is in the end a judgment call by the administrator. That judgment is based upon science and the law,” McCarthy said.
Mining, electric trade groups react to ozone rule
“The new ozone standard continues EPA’s spotless record for irresponsible policies that ignore costs and exaggerate benefits,” said National Mining Association (NMA) President and CEO Hal Quinn.
“EPA attributes few health benefits directly to smog reduction. This isn’t surprising since current ozone levels are down 33% since 1980 and current standards already protect human health. Just as it did with its mercury rule recently voided by the Supreme Court, EPA again relies on previous regulations to claim ‘co-benefits’. To most people, that means ‘no benefits,’” said NMA’s Quinn.
Edison Electric Institute (EEI) President Tom Kuhn said that the electric power sector has made great progress in reducing the environmental impact of electricity generation, cutting sulfur dioxide (SO2) emissions by 80% and nitrogen oxides (NOx) emissions by 74% since 1990, even as demand for electricity has increased.
“While we are still reviewing the final standard, EEI advocated throughout the rulemaking process that, should a new ozone standard be set, it should be at the top end of the proposed range at 70 parts-per-billion (ppb),” Kuhn said. “While compliance challenges remain with the new standard at 70 ppb, EPA has recognized the serious implementation concerns raised by stakeholders of setting the standard below 70 ppb.
“EEI will continue to work with our members, the states, and affected customers to determine how compliance with the new ozone standard will impact the implementation of other major EPA regulations, including the Mercury and Air Toxic Standards (MATS), and, importantly, the recently finalized Clean Power Plan,” Kuhn added.