A coalition of environmental groups says oil trains are making people in Albany sick, and they're asking state regulators to investigate.

The group includes the Sierra Club, Environmental Advocates of New York and Earthjustice. They wrote to the state's Department of Environmental Conservation on Friday asking for a "comprehensive" review of the impact oil trains have on surrounding air quality.

Residents living near the Port of Albany and the rail lines carrying the trains have complained of health problems they believe are associated with oil and diesel emissions.

The state's environmental agency tested the air near the Port of Albany earlier this year and reported no problems. There was no immediate response Friday to the request for an additional study.