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Danger in the Air—Report Highlights Smoggiest U.S. Cities

Danger in the Air—Report Highlights Smoggiest U.S. Cities

Environment Ohio

Americans should be able to breathe clean air, but pollution from power plants and vehicles puts the health of our nation at risk. Ground-level ozone, the main component of smog, is one of the most harmful and pervasive air pollutants. According to the American Lung Association, nearly half of all Americans—48 percent—still live in areas with unhealthy levels of smog pollution. Studies show that on days with high concentrations of smog pollution, children and adults suffer more asthma attacks, increased respiratory difficulty and reduced lung function. Exposure to smog pollution can exacerbate respiratory illness and cause premature death. Sensitive populations including children, the elderly and people with respiratory illness are particularly at risk.

Though air quality has improved significantly in the last decade as a result of policies at the state and federal level, there is still much to be done, as there are still millions of people living in metropolitan areas exposed to unhealthy levels of pollution. This report ranks metropolitan areas for their unhealthy air days in 2010 and 2011.

This report also presents data indicating that the problem may have been worse than we thought. Because the national health standard for smog pollution set in 2008 was set at a level that scientists agree is not protective of public health, people across the country have been exposed to days of poor air quality each summer without knowing it. We have calculated the additional days on which the air was unhealthy to breathe, according to a pollution threshold that is more consistent with what scientists say is necessary to protect public health, but because the 2008 standard was set too loosely, the public was not alerted.

The major data and findings of our report are broken down into the following categories:

National rankings of the smoggiest metropolitan areas across the country in 2010: The top five smoggiest metropolitan areas in the country in 2010 were in California. Riverside-San Bernardino, Calif. ranked as the smoggiest metropolitan area in the country with 110 smog days, meaning that the area—home to more than 3 million residents—had unhealthy air on one out of three days in 2010. Baltimore;D.C.; Philadelphia;  Houston; and Atlanta made up the rest of the top-ten smoggiest metropolitan areas list for 2010.

Rankings of smoggiest cities across the country by population size:

  • Of large metropolitan areas, or those with populations over 1 million people, Riverside-San Bernardino, Calif. suffered the worst smog pollution in 2010 by far, with 41 more days than the area in second place: Los Angeles-Long Beach, Calif. The top five continue with Baltimore; D.C.; and Philadelphia. Two metropolitan areas in each of the following states were among the top 20 smoggiest large areas for 2010: New Jersey, New York, North Carolina, Ohio, Pennsylvania and Texas.
  • Among mid-sized metropolitan areas, or those with populations between 250,000 and 1 million people, areas in California again topped the list for worst smog pollution, followed by areas in Tennessee, Delaware, New Jersey, Louisiana, Alabama and Ohio. The top twenty smoggiest mid-sized metropolitan areas include three areas in both Ohio and Pennsylvania and two areas each in Louisiana, Texas and Connecticut.
  • San Luis Obispo-Atascadero-Paso Robles, Calif. was the smoggiest small metropolitan area (population less than 250,000) in 2010. Three places in Wisconsin were among the top 10 smoggiest small metropolitan areas.

State-by-state rankings of smog in 2010: Across the state of California, there were 135 days in 2010—or more than a third of the year—when at least part of the state experienced smog levels exceeding the health standard. California, Texas, Utah, Maryland, Pennsylvania, New Jersey, Ohio and New York each had at least 30 days in 2010 when part of the state experienced smog levels exceeding the health standard—as many as a month’s worth of days when breathing the air could put people’s health at risk. Seventeen states experienced at least one red alert day for unhealthy air, indicating pollution levels high enough in a particular area so that anyone could start experiencing adverse health effects. Nine states did not record any days in 2010 on which levels of smog pollution exceeded the standard: Alaska, Hawaii, Idaho, Montana, Nebraska, North Dakota, South Dakota, Vermont and Wyoming.

National rankings of the smoggiest metropolitan areas across the country in 2011, through August 21: The areas of Los Angeles-Long Beach-Riverside, Calif.; Atlanta-Sandy Springs-Gainesville, Ga. and Ala.; Fresno-Madera, Calif.; D.C.; Baltimore; New York; Newark, N.J.; Bridgeport, Conn.; and Bridgeport, Pa. were the top areas with the most smog days this past summer, through August 21, 2011.

The air was unhealthy to breathe many more times in 2010 and in 2011 than the public was alerted to because the 2008 standard was not set at a level to protect public health. To demonstrate the discrepancy between the ozone standard set in 2008 (75 parts per billion) and a level that scientists agree is more protective of public health (60-70 parts per billion), this report also looks at the number of times that air monitors recorded a level of 71-75 ppb in 2010, and calculates how many additional days in each metropolitan area the public was exposed to unhealthy air according to a more protective level of 70 ppb. For example, in the Riverside-San Bernardino, Calif. area, there were 110 days when pollution levels exceeded the existing health standard, but there were an additional 25 days on which pollution levels exceeded a level that scientists agree is more protective of public health.

Policy Recommendations

To protect the health of our children and people across the country, many steps can be taken both at the state and federal level to reduce dangerous pollution. First, the U.S. Environmental Protection Agency (EPA) must set a national ambient air quality standard for ground-level ozone within the range of 60 to 70 parts per billion averaged over 8 hours, as unanimously recommended by the independent board of air experts and scientists created under the Clean Air Act to provide periodic review and recommendations on air quality standards. The Obama administration considered updating the 2008 standard, but decided in early September 2011 to abandon this effort and update the standard in 2013.

Pollution from cars and trucks—which accounts for a third of smog-forming nitrogen oxide emissions in the U.S.—must be cleaned up by developing cleaner and more efficient vehicles and by improving and expanding public transportation systems.

State and federal governments should accelerate the transition away from fossil fuels and toward a clean energy economy by passing policies to ensure we get more of our energy from clean, renewable sources such as wind and solar power.

Lastly, Congress should eliminate subsidies that help keep our nation dependent on polluting fossil fuels that put our health and environment at risk. Dirty energy pollutes the air we breathe, threatening our health and our environment. When power plants burn coal, oil or gas, they create the ingredients for ground-level ozone pollution, one of the main components of smog pollution. Especially on hot summer days, across wide areas of the U.S., ozone pollution reaches levels that are unhealthy to breathe, putting our lives at risk. In 2009, U.S. power plants emitted more than 1.9 million tons of ozone-forming nitrogen oxide pollution into the air.

In order to better protect public health, the U.S. EPA should issue a new air quality standard to reduce ground-level ozone pollution. To achieve these reductions in pollution, the U.S. should increase pollution control technologies for power plants and accelerate the transition to clean electricity sources, including wind and solar power. In addition, the U.S. should reduce ozone-forming pollution from mobile sources. Emissions from power plants contribute to widespread ozone pollution. More than half of the people in the United States—56 percent—live in areas with unhealthy levels of ozone.

Power plants emitted 1,927,569.3 tons of nitrogen oxide pollution—a key precursor to ozone pollution—into the environment in 2009. Emissions from power plants in just 11 states account for 50 percent of the total nitrogen oxide pollution emitted by power plants. Repeated exposure to ozone can cause permanent lung damage. According to a RAND Corporation health study—in California alone—high levels of ozone pollution contributed to nearly 30,000 emergency room visits and hospital admissions and $193 million in hospital medical care from 2005 to 2007.

Children and adults suffer more asthma attacks and increased respiratory difficulty when exposed to ozone pollution. Approximately 3.9 million children and more than 10.7 million adults with asthma live in regions with very high levels of ozone pollution. According to the United States Department of Health and Human Services, approximately 5,000 asthma-related deaths occur each year in the U.S. Children are particularly vulnerable. Children who grow up in areas with high levels of ozone pollution may develop diminished lung capacity, putting them at greater risk of lung disease later in life.

Ozone exposure can impact prenatal health, with research finding that in utero exposure to ozone is associated with lower birth weight and intrauterine growth retardation. Emission controls are helping to reduce health-threatening, ozone-forming pollution from power plants. In the last five years, thanks to standards set by the U.S. EPA, coal-fired power plants achieved reductions in their emissions of nitrogen oxides by an average of 74 percent. Overall electric-sector nitrogen oxide pollution has dropped by almost half without noticeably affecting electricity prices or the reliability of the power system. However, federal standards for ground-level ozone are not sufficiently protective of public health and power plant emissions are still too high. Research shows that the current 8-hour ground-level ozone standard of 75 parts per billion (ppb) set in March 2008 under the Bush administration leaves millions at risk. U.S. EPA analysts project that a standard in the range of 60-70 ppb would prevent as many as 12,000 premature deaths per year from heart or lung diseases, along with thousands of cases of bronchitis, asthma and nonfatal heart attacks.

More action is necessary to protect our health and environment from ground-level ozone pollution. To protect our health and our environment, the U.S. EPA should establish a national ambient air quality standard for ground-level ozone of no higher than 60 parts per billion. Power plants should continue to implement more advanced emission control technologies like selective catalytic reduction systems to reduce ozone-forming nitrogen oxide emissions, and ultimately help areas meet the U.S. EPA air quality standard.

Additionally, to help reduce pollution, state and federal governments should accelerate the transition away from fossil fuels and toward a clean energy economy. Important steps include: Establishing or increasing renewable electricity standards to ensure that at least 25 percent of U.S. electricity comes from renewable sources of energy such as wind and solar by 2025; strengthening energy efficiency standards and codes for appliances, and requiring all new buildings use zero net energy by 2030; ramping up investment in solar power through tax credits, specific solar generation targets in state renewable electricity standards, requirements for solar ready homes, rebate programs and other measures; and ending subsidies for fossil fuel industries.

For more information, click here.

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A net-casting ogre-faced spider. CBG Photography Group, Centre for Biodiversity Genomics / CC BY-SA 3.0

Just in time for Halloween, scientists at Cornell University have published some frightening research, especially if you're an insect!

The ghoulishly named ogre-faced spider can "hear" with its legs and use that ability to catch insects flying behind it, the study published in Current Biology Thursday concluded.

"Spiders are sensitive to airborne sound," Cornell professor emeritus Dr. Charles Walcott, who was not involved with the study, told the Cornell Chronicle. "That's the big message really."

The net-casting, ogre-faced spider (Deinopis spinosa) has a unique hunting strategy, as study coauthor Cornell University postdoctoral researcher Jay Stafstrom explained in a video.

They hunt only at night using a special kind of web: an A-shaped frame made from non-sticky silk that supports a fuzzy rectangle that they hold with their front forelegs and use to trap prey.

They do this in two ways. In a maneuver called a "forward strike," they pounce down on prey moving beneath them on the ground. This is enabled by their large eyes — the biggest of any spider. These eyes give them 2,000 times the night vision that we have, Science explained.

But the spiders can also perform a move called the "backward strike," Stafstrom explained, in which they reach their legs behind them and catch insects flying through the air.

"So here comes a flying bug and somehow the spider gets information on the sound direction and its distance. The spiders time the 200-millisecond leap if the fly is within its capture zone – much like an over-the-shoulder catch. The spider gets its prey. They're accurate," coauthor Ronald Hoy, the D & D Joslovitz Merksamer Professor in the Department of Neurobiology and Behavior in the College of Arts and Sciences, told the Cornell Chronicle.

What the researchers wanted to understand was how the spiders could tell what was moving behind them when they have no ears.

It isn't a question of peripheral vision. In a 2016 study, the same team blindfolded the spiders and sent them out to hunt, Science explained. This prevented the spiders from making their forward strikes, but they were still able to catch prey using the backwards strike. The researchers thought the spiders were "hearing" their prey with the sensors on the tips of their legs. All spiders have these sensors, but scientists had previously thought they were only able to detect vibrations through surfaces, not sounds in the air.

To test how well the ogre-faced spiders could actually hear, the researchers conducted a two-part experiment.

First, they inserted electrodes into removed spider legs and into the brains of intact spiders. They put the spiders and the legs into a vibration-proof booth and played sounds from two meters (approximately 6.5 feet) away. The spiders and the legs responded to sounds from 100 hertz to 10,000 hertz.

Next, they played the five sounds that had triggered the biggest response to 25 spiders in the wild and 51 spiders in the lab. More than half the spiders did the "backward strike" move when they heard sounds that have a lower frequency similar to insect wing beats. When the higher frequency sounds were played, the spiders did not move. This suggests the higher frequencies may mimic the sounds of predators like birds.

University of Cincinnati spider behavioral ecologist George Uetz told Science that the results were a "surprise" that indicated science has much to learn about spiders as a whole. Because all spiders have these receptors on their legs, it is possible that all spiders can hear. This theory was first put forward by Walcott 60 years ago, but was dismissed at the time, according to the Cornell Chronicle. But studies of other spiders have turned up further evidence since. A 2016 study found that a kind of jumping spider can pick up sonic vibrations in the air.

"We don't know diddly about spiders," Uetz told Science. "They are much more complex than people ever thought they were."

Learning more provides scientists with an opportunity to study their sensory abilities in order to improve technology like bio-sensors, directional microphones and visual processing algorithms, Stafstrom told CNN.

Hoy agreed.

"The point is any understudied, underappreciated group has fascinating lives, even a yucky spider, and we can learn something from it," he told CNN.


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