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List of State Officials - Martin O'Malley, Governor; Anthony Brown, Lt. Governor; Shari T. Wilson, MDE Secretary 

Volume IV, Number 3

 February 2010

eMDE is a quarterly publication of the Maryland Department of the Environment. It covers articles on current environmental issues and events in the state. 

U.S. EPA Strengthens Smog Standard

By Kim Lamphier, Office of Communications

Back to this issue's cover page 

In January, the U.S. Environmental Protection Agency proposed the strictest health standards to date for smog – a move that drew approval from Maryland, the District of Columbia, and the 11 other Mid-Atlantic and Northeast states on the Ozone Transport Commission (OTC). 

 “The OTC States have worked collaboratively to meet federal ozone standards and will do the same to meet these standards,” said OTC Chair and MDE Secretary Shari T. Wilson. “The proposed new standards, which are critical for public health and environmental protection, demonstrate EPA’s commitment to science and will require a much stronger action to address transport. We commend EPA.” 

The move will also necessitate the need for a strong federal interstate transport rule to control ozone transported to Maryland from out-of-state. This is critical for Maryland because over 50 percent of our ozone-forming pollution comes from other states.

Once the standards are adopted, Maryland will develop a State Implementation Plan detailing a strategy for meeting the new standard. Simultaneously, Maryland is working with the OTC and EPA to establish national control measures for nitrogen oxides (NOx) and volatile organic compounds (VOCs), the two precursors to ozone, and to address the issue of transport.

EPA announced in January its proposal to replace the standards set by the previous administration, which many believe were not protective enough of human health. The new standards are based on a review of more than 1,700 scientific studies and establish a primary standard to protect human health and a secondary standard to protect ecological health.

Smog, also known as ground-level ozone, is linked to a number of serious health problems, ranging from aggravation of asthma to increased risk of premature death in people with heart or lung disease. Ozone can even harm healthy people who work and play outdoors. Children are at the greatest risk from ozone, because their lungs are still developing, they are most likely to be active outdoors, and they are more likely than adults to have asthma. Adults with asthma or other lung diseases and older adults are also sensitive to ozone. The EPA proposal is designed to help reduce premature deaths, aggravated asthma, bronchitis cases, hospital and emergency room visits, and days when people miss work or school because of ozone-related symptoms.

Ozone forms when emissions from industrial facilities, power plants, landfills, and motor vehicles react in the sun. The agency is proposing to toughen the "primary" standard, which protects public health, and a separate "secondary" standard to protect the environment, especially plants and trees. 

EPA will take public comment for 60 days after the publication of the proposed rule in the Federal Register. The proposed rule was published January 19, according to EPA’s website, and the Agency held three public hearings on the proposal.

For more information visit:

Click here  for MDE’s Air Quality Planning Program.

Click here for EPA’s Ground-Level Ozone Program.

Click here  for the Ozone Transport Commission. 


©2010 Copyright MDE

Editorial Board
Maryland Department of the Environment
1800 Washington Boulevard, Baltimore, MD 21230