Maine’s Environment 1994

It is estimated that air pollutants in the state may exaggerate certain non-cancer chronic conditions linked with 24,000 hospitalizations and 3,000 deaths annually in Maine. With passage of the federal Clean A- Act in 1970, and amendments in 1977 and 1990, Maine's understanding and control of air pollutants have steadily improved.

Most criteria air pollutants are below state and federal standards in Maine and have been relatively stable since 1984. The exception is ground-level ozone. Ozone is not emitted directly from a source but forms by the reaction of hydrocarbons and nitrogen oxides in sunlight. Currently, parts of Maine are not in compliance with state or federal standards for ozone.

The single largest contributor of ozone's key ingredients is motor vehicle emissions. Maine has a three-part strategy to minimize in-state sources of ozone: an auto emissions testing program in the southern portion of the state; reformulated gasoline for the summer months so that cars burn cleaner; and a low emission vehicle program scheduled for 1996. Transportation also is the largest contributor of carbon monoxide emissions and the second largest contributor for CO₂ and methane in Maine.

In addition to ozone, air toxics are a concern of the 199Os. In 1992, Maine industries emitted over 13.2 million pounds of toxic contaminants to the air, but programs to analyze their effects are in their infancy. DEP monitored levels of chloroform, tetrachloroethylene, benzene, toluene, xylene, 1,3 butadiene and carbon tetrachloride in 1991 and 1992. In 1994, continuous monitoring of air toxics in southern and western Maine is being done to gain a better understanding of the nature and extent of the problem.

Criteria Air Pollutants

Ozone

Sulfur Dioxide

Nitrogen Oxide

Lead

Particulates

Carbon Monoxide

Challenges for the Future

While we have some idea which air toxics are emitted and at what levels hazardous air pollutants are of concern, we know how the emissions are dispersed or transformed and what ambient concentrations are found in Maine. This is a major challenge.

Radon is a radioactive gas that comes from the natural decay of uranium found in nearly all rocks. Radon is believed to rank second to cigarette smoke as a cause of lung cancer, and contributes to 35 to 67 deaths per year in Maine. Surveys indicate that one out of three homes in Maine may have elevated levels of radon. Educating the public as to the need for radon screening and mitigation will be one of the challenges of the next decade.