WASHINGTON, DC, January 28, 2010 (ENS) - EPA Regulates Short-Term Exposure to Air Pollutant Nitrogen Dioxide

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EPA Regulates Short-Term Exposure to Air Pollutant Nitrogen Dioxide

WASHINGTON, DC, January 28, 2010 (ENS) - Concentrations of the

air pollutant nitrogen dioxide must be below 100 parts per billion in

any one-hour period under a new national air quality standard for the

reactive gas set Monday by The U.S. Environmental Protection Agency.

The new one-hour standard is intended to protect Americans from peak

short-term exposures to nitrogen dioxide, NO2, which is formed from

vehicle, power plant and other industrial emissions, and contributes to

the formation of fine particle pollution and smog.

The new one-hour standard supplements the existing annual average standard of 53 ppb.

This is the first revision to the national air quality standard for

nitrogen dioxide since the current standard was adopted in 1971 and it

includes the first network of roadside monitors for any motor vehicle

pollutant.

"For the first time ever, we are working to prevent short-term

exposures in high risk NO2 zones like urban communities and areas near

roadways," said EPA Administrator . "This new one-hour standard is designed to protect the air we

breathe and reduce health threats for millions of Americans,"

said.

EPA is establishing requirements for an NO2 monitoring network that

will include monitors at locations where maximum NO2 concentrations are

expected to occur, including within 50 meters of major roadways, as

well as monitors sited to measure the area-wide NO2 concentrations that

occur more broadly across communities.

Residential apartment buildings line the Cross Bronx Expressway, New York City (Photo by Siebert)

Under the new monitoring requirements to measure NO2 levels,

monitors must be located near roads in cities with at least 500,000

residents.

Existing community-wide monitoring will continue in cities with at least one million residents.

Working with the states, says the EPA will site at least 40

monitors in locations where communities are vulnerable to elevated

levels of NO2. Larger cities and areas with major roadways will have

additional monitors. Based on the existing monitoring network, the EPA expects to

identify or designate areas not meeting the new standard by January

2012.

New monitors must begin operating no later than January 1, 2013. When

three years of air quality data are available from the new monitoring

network, EPA intends to redesignate areas as appropriate. Connor, president and CEO of the American Lung

Association, welcomed the new standard, calling it a good first step.

but said the EPA's original proposal last summer was more protective. "After waiting 38 years, we had frankly hoped for a stronger,

more protective standard. Their decision allows areas to have nitrogen

dioxide concentrations that remain hazardous to the millions of people

who will have to breathe them," Connor said. "Their final decision,

unlike their proposal of last summer, allows twice as many days when

nitrogen dioxide will spike to dangerous levels." "Unfortunately," he said, "that burden is likely to fall

hardest on those who can least bear it - children, older adults, people

with lung disease, as well as people with low incomes, and communities

of color."

Connor pointed to a review of the evidence of the threats to health

from living near a highway issued January 13 by the Health Effects

Institute, a research center funded by the motor vehicle industry and

EPA. The HEI quoted the conclusions of an expert panel that

breathing the nitrogen dioxide and other pollutants from highway

traffic increased the risk that a child's asthma would get worse.

Strong evidence warned that pollution from traffic may even increase

the risk that children could develop asthma, or worsen their lungs'

ability to function.

A residential area next to the highway serving the SeaTac airport near Seattle and Tacoma, Washington (Photo by Derrick Coetzee)

For older adults and people with cardiovascular disease, living near a

highway may increase the risk of early death, the review showed. "Neighborhoods near major highways are often home to people

with lower incomes, as well as communities of color," Connor said.

"Many busy highways pass through dense urban neighborhoods or near

schools. Those communities often have higher prevalence of lung

disease, putting them at even greater risk from breathing traffic

exhaust." The Institute's report states, "Based on a synthesis of the

best available evidence, the Panel identified an exposure zone within

300 to 500 meters from a highway or major road as the area most highly

affected by traffic emissions and estimated that 30% to 45% of people

living in large North American cities live within such zones." said the new standard is intended to protect the health

of these very populations - people with asthma, children and the

elderly living near major roads and highways. The EPA points to current scientific evidence linking

short-term NO2 exposures, ranging from 30 minutes to 24 hours, with

adverse respiratory effects including increased asthma symptoms, more

difficulty controlling asthma, and an increase in respiratory illnesses

and symptoms.

Studies also show a connection between short-term exposure and

increased visits to emergency departments and hospital admissions for

respiratory illnesses. "Improving air quality is a top priority for this EPA," said

. "We're moving into the clean, sustainable economy of the 21st

century, defined by expanded innovation, stronger pollution standards

and healthier communities." The Clean Air Act requires EPA to set national ambient air

quality standards for "criteria pollutants." Currently, nitrogen oxides

and five other major pollutants are listed as criteria pollutants. The

others are ozone, lead, carbon monoxide, sulfur oxides, and particulate

matter.

All areas presently meet the current (1971) NO2 national ambient air

quality standards, with annual NO2 concentrations measured at area-wide

monitors well below the level of the standard of 53 parts per billion.

Annual average ambient NO2 concentrations, as measured at area-wide

monitors, have decreased by more than 40 percent since 1980, the EPA

states in connection with this rule. Currently, the annual average NO2

concentrations range from approximately 10-20 ppb. EPA expects NO2 concentrations will continue to decrease in the

future as a result of a number of mobile source regulations that are

taking effect. Tier 2 standards for light-duty vehicles began phasing

in during 2004, and new NOx standards for heavy-duty engines are

phasing in between 2007 and 2010 model years. Current air quality

monitoring data reflects only a few years of vehicles entering the

fleet that meet these strict NOx standards.

Click here to read the new final rule regulating nitrogen dioxide. URL: http://www/epa.gov/ttn/naaqs/standards/nox/data/20100122fr.pdfCopyright Environment News Service (ENS) 2010. All rights reserved.------------------------------------------------------------------------------------------------------------------------------------URL: http://www.ens-newswire.com/ens/jan2010/2010-01-28-091.html