It’s Not Just Hot in Boston Right Now: Air Quality Has Been Deemed “Unhealthy”

A warning from the state is in effect for the day.

air quality map massachusetts

Map screenshot via Massachusetts Department of Environmental Protection

Looks like it’s not just an extremely sweaty subway ride you’ve got to worry about right now in Boston. According to a warning from the state, the air quality for much of the city has been found to be temporarily “unhealthy.”

A large swath of air in Boston has been deemed “moderate” by the state Department of Environmental Protection’s standards. “Air quality is acceptable; however, for some pollutants there may be a moderate health concern for a very small number of people,” the agency says in a description of that designation on its website. “Unusually sensitive people,” it adds, which can include those with severe asthma or lung or heart disease, “should consider reducing prolonged or heavy exertion outdoors.”

An alert about diminished air quality is expected to remain in effect between 11 a.m. and 11 p.m. Tuesday, according to an official DEP tweet.

At Harrison Ave. in Roxbury, the department found a concerning cocktail of fine particles, carbon monoxide, nitrogen dioxide, ozone, and sulfur dioxide, according to a tracking tool on its website. At Von Hillern Street in Dorchester, notable levels of carbon monoxide and nitrogen dioxide were detected.

It varies, though. In Kenmore Square, the air quality is still deemed “good.” Other areas nearby where the department found “moderate” air quality can be found in Lynn, Chelmsford, Haverhill, and Fall River.

The DEP identifies a handful of causes for unusual levels of pollutants in the air, among them the direction of the wind and certain weather conditions. Warm weather and increases in direct sunlight can drive up the production of ozone, the DEP says.

To call this weather warm is, clearly, an understatement. With possible heat indices reaching near 100 degrees today, the National Weather Service in Boston has issued a heat advisory for eastern Massachusetts, as well as Rhode Island and the Connecticut River Valley, and is urging all of us to take precautions, including avoiding direct sunlight or strenuous activities outdoors.