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          The desolation of smog: World battles against air pollution

          Updated: 2014-02-27 17:51 (chinadaily.com.cn)
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          Almost a seventh of China's land has been engulfed by heavy smog with the air pollution in 20 cities reaching "danger level". China is not alone however. Many countries, during industrial and economic development, have been confronted by the same problem. The crisis of air pollution is an issue from which we cannot hide.

          United States

          The desolation of smog: World battles against air pollution
          Heavy smoke lingers over the Los Angeles skyline Nov 16, 2008.[Photo/icpress.cn] 

          Since the beginning of the Industrial Revolution in the United States, America has had trouble with environmental issues, air pollution in particular. Roughly 60 percent of Americans live in areas where air pollution has reached unhealthy levels that can make people sick, suggests the 2009 State of the Air report released by the American Lung Association.

          Los Angeles has some of the most contaminated air in the country with diesel engines, ports, motor vehicles and industries the main sources. Frequent sunny days and low rainfall contribute to ozone formation, as well as high levels of fine particles and dust.

          The desolation of smog: World battles against air pollution

          Efforts

          The US created the Environmental Protection Agency in 1970 and passed the Clean Air Act. The act originally empowered the EPA to determine safe limits and regulate six major air pollutants, now expanded to 189 potential threats.

          Smoking was increasingly restricted on planes until it was finally banned in 2000, when exceptions for flights to and from the US were abolished. Indoor smoking bans are now de rigueur across the nation.

          The EPA replaced the Pollution Standards Index with the Air Quality Index in 1999 to incorporate new PM2.5 and ozone standards.

          The US Congress authorized funding for the Diesel Emissions Reduction Act, a grant program, administrated by the EPA, in 2005 to selectively retrofit or replace older diesel engines most likely to impact human health.

          The "Clean up Green up" campaign was launched in 2011 to designate three low-income LA communities - Pacoima, Boyle Heights and Wilmington. The campaign aims to push green industries through incentives, including help obtaining permits and tax and utility rebates.

          The desolation of smog: World battles against air pollution

          Improvement

          Thanks to the Clean Air Act, many people in the US are breathing a little easier. The American Lung Association's "State of the Air 2013" report, which analyzed ozone and airborne particle levels from 2009 to 2011, showed that overall the nation's air quality is much cleaner, especially compared to a decade ago.

          From 1980 to 2000, according to a 2009 study in the New England Journal of Medicine, average life expectancy increased five months because of the nationwide decrease in air pollution.

          Concentrations of carbon monoxide – once spewed by every car and truck but now removed by catalytic converters – have dropped by about 90 percent in large American cities.

          Concentrations of particulate matter, a classification covering a wide range of pollutants in the microscopic to near-microscopic range, have dropped by about 80 percent from their peak, and ozone has plummeted as well.

          Lead emissions fell by more than 98 percent.

          According to a 2012 study by the National Oceanic and Atmospheric Administration, the levels of certain vehicle-related pollutants in Los Angeles have dropped by 98 percent since the 1960s.

          The desolation of smog: World battles against air pollution
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