The city of Warsaw mas made public transportation free for a day due to heightened air pollution, a step meant to encourage residents to leave their cars at home.
Poland, which burns large amounts of coal to keep its industries running and homes warm, has the second highest air pollution levels in Europe after Bulgaria, according to the 2016 report on air quality in Europe by the European Environment Agency.
City hall said the unusually bad air quality forecast for Thursday in the capital city of 1.7 million is due to a combination of cold temperatures, which increases residential heating, and low winds. It urged that the elderly, children, people with asthma and heart and respiratory diseases avoid prolonged stays outdoors.
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