
The Massachusetts Department of Environmental Protection has issued an air quality alert for several counties in the state on Wednesday.
The alert warns of an anticipated increase in ozone levels in eastern and southeastern parts of the commonwealth, officials said Tuesday. The alert is in eastern parts of Essex County, southern Bristol County and Barnstable, Dukes and Nantucket counties from 11 a.m. through 11 p.m. Wednesday.
Air in the impacted areas is expected to be unhealthy for sensitive groups, which includes people with heart or lung disease, such as asthma, as well as older adults, children, teenagers and people who are active outdoors, according to the environmental agency.
People in those groups were urged to reduce prolonged or heavy outdoor exercise, take additional breaks and do less intense activities while the alert is in effect, watching out for symptoms like coughing and shortness of breath.
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The air quality advisory comes as high temperatures sweep much of New England.
Mayor Michelle Wu declared a heat emergency in Boston, which is in effect through Thursday. That emergency declaration, which was issued Monday, opened cooling centers at a dozen Boston Centers for Youth & Families community centers.