A coalition of eight north-eastern US states has filed a lawsuit against the federal Environmental Protection Agency in an attempt to get it to force other states to impose more stringent air pollution controls. The litigating states – Connecticut, Delaware, Maryland, Massachusetts, New York, Pennsylvania, Rhode Island and Vermont – argue that air emissions from coal-fired power plants in the other states negatively affect their own citizens. They began their action in 2013 by asking the EPA to add the states of Illinois, Indiana, Kentucky, Michigan, North Carolina, Ohio, Tennessee, Virginia and West Virginia to the ‘Ozone Transport Region’ which is subject to more stringent air pollution limitations. Earlier this year, however, the EPA rejected the request, leading to the litigation against the EPA itself.