Overall air pollution continued an eight-year decline in 1983, the Environmental Protection Agency reported Thursday in its annual air quality review, but officials said that two prime components of urban smog, ozone and nitrogen dioxide, showed worrisome signs of increasing.
The results suggested that some pollution controls may be reaching their peak effectiveness and that air quality will begin deteriorating unless “tough, maybe disruptive and difficult” new curbs are imposed, the officials said.
The review, based on data from hundreds of monitoring stations, tracked changes in the levels of six EPA-regulated air pollutants: sulfur dioxide, carbon monoxide, nitrogen dioxide, ozone, particulates and lead. The pollutants are widely linked to respiratory diseases and, in the case of lead, to a range of disorders of the nervous system and organs.
Down Since 1975
Levels of all six have dropped since monitoring began in 1975, the EPA said, and five of the six either declined or remained steady between 1982 and 1983.
But concentrations of ozone, the sixth pollutant, increased 12% during 1983. The rise was recorded everywhere except the Pacific Northwest. And Charles L. Elkins, the EPA’s assistant administrator for air and radiation, said some studies also suggest that nitrogen dioxide levels--which basically were stable during 1983--may begin rising in the early 1990s without further controls.
Richard Rhoads, an air monitoring expert with the EPA, called the sudden jump in ozone levels “troublesome, but not an indication that our (anti-pollution) program is failing.” Rhoads said increased industrial activity and poor weather conditions probably combined to produce a one-year leap in concentrations of the chemical.
Sunlight, Exhaust Combine
Ozone is formed when sunlight reacts with nitrogen dioxide, a product of auto exhaust, and volatile organic gases. The EPA estimates that emissions of volatile organics increased 3% in 1983, and Rhoads said that an unusually hot summer probably “cooked up” higher-than-expected amounts of ozone.
With the exception of lead--which continued a decline that began when unleaded gasoline first was marketed in the mid-1970s--levels of other regulated pollutants declined only slightly during 1983.
Some of those levels were unhealthy. Last year, the EPA estimated, 14 million Americans lived in areas where the legal standard for sulfur dioxide was exceeded, and more than 60 million persons lived in areas that did not meet particulate and carbon monoxide standards.
The EPA said, as it has annually, that the pervasive pollution in Los Angeles makes it “impossible” for the region to attain federal air quality standards by the 1987 deadline.
“Some people say they may never get into attainment,” Elkins said.
Ironically, the EPA report noted, the Los Angeles area has achieved far greater reductions in lead, sulfur dioxide and carbon monoxide than the national average and has matched the nation in reducing other pollutants.
Further gains will be increasingly difficult to achieve, Elkins and Rhoads said. Basic curbs on pollution imposed in the 1970s have done their work, and growth in traffic and industrial output could “overwhelm” past improvements without new controls.
“We’ve done the easy things,” Elkins said. “We may be faced in the next few years with some tough decisions. . . . Some of them may be disruptive and difficult.”
This summer the EPA will issue costly new rules curbing sulfur dioxide emissions from tall smokestacks. The agency also is studying potentially costly and unpopular controls on gasoline vapors from service station pumps and auto tanks.
Future pollution cuts may come from millions of small businesses, such as dry cleaners, that so far have escaped regulation.
In a related matter, the EPA issued a draft study suggesting that its controls on the six air pollutants also have cut in half the incidence of cancer related to so-called toxic air pollutants.
Emissions of most toxic gases, including many solvents and industrial chemicals such as formaldehyde, are not explicitly regulated by the EPA. After December’s poison gas disaster in Bhopal, India, the agency has come under congressional criticism for failing to address the health hazards posed by such gases.
The draft EPA report concluded that “excess” cancers in 11 study areas have been cut 56%, in part because federal air-pollution controls have indirectly reduced toxic gas emissions. Federal curbs on ozone and particulates are responsible for most of the reduction in toxic emissions, officials said, and shifts away from coal-burning heating systems also contributed to the reduction in cancers.