BOSTON (AP) - Environmental officials say New Englanders experienced an overall decrease in the number of unhealthy air quality days this year during the summer ozone season.
Between April and September 2013, air quality monitors recorded 20 days when ozone levels in New England exceeded levels considered healthy, compared to 29 days during the same period in 2012.
The U.S. Environmental Protection Agency said the downward trend started about 30 years ago and is due to reductions in the emissions that form ozone.
In 1983, New England had 113 unhealthy days, compared to 20 this year.
Maine was the only state to see a rise in unhealthy days, recording five in 2013, up from four the year before. Vermont had no unhealthy days either year.
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