(CN) - The Environmental Protection Agency has failed to take action on ozone pollution proposals from 13 states, preventing enforcement or changes in the laws, environmental groups say District of Columbia Federal Court. The Sierra Club and WildEarth Guardians say the EPA failed to take final action on the proposals by April 2009, a year after the deadline for states to submit their final implementation plans to manage ozone pollution.
The Clean Air Act sets a process for establishing national ambient air quality standards, and the requirement for 8-hour ozone standards dates back to 1997.
The environmentalists say states still lacking final action are Maine, Rhode Island, Connecticut, Ohio, Louisiana, Kansas, Nebraska, Missouri, Colorado, Montana, South Dakota, Utah and Wyoming.
Represented by Robert Ukeiley in Berea, Ky., the groups want the EPA to take final action on the ozone plans.
Ozone in the upper atmosphere protects life on earth by reflecting harmful ultraviolet solar rays back into space. Tropospheric ozone, or ozone at ground level, comes from the interaction of light with vehicle and industrial emissions. Also known as smog, ground-level ozone reduces or prevents plants' ability to absorb carbon dioxide and damages lung tissue in animals.
Ozone dissolved in water has powerful, short-lived antibiotic properties and has been used to fight infection.
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