That's according to the "18th Annual State of the Air Report" released Wednesday from the American Lung Association. They said Bangor and Portland saw improved numbers.
Bangor again had a very low rating compared to Maine and the country. Only one high ozone day in the period measured and that's the same as last year so Penobscot County got a "B" grade for ozone.
ALA Maine Director Lance Boucher said "Only York County earned a failing grade for ozone, although officials say there's reason for concern in Hancock County."
That county actually saw an increase in the amount of high ozone days, causing them to earn a grade of "C" for ozone.
The American Lung Association said pollution coming from other states is the cause for the bad ozone in Hancock County.
They also say dismantling laws focusing on health, could back track the ozone-reduction most places in Maine have seen.