[ad_1]
People traveling on subway systems in major US cities are exposed to dangerous amounts of air pollution, with commuters in New York and New Jersey experiencing the highest levels of pollution, research shows.
Tiny airborne particles, likely thrown by train brakes or the friction between the train’s wheels and tracks, plague the 71 subway stations the researchers sampled during the morning and evening rush hours in Boston, New Brunswick. York, Philadelphia and Washington DC, the cities that contain the bulk of the subway systems in the United States.
The levels of these tiny pollution particles, known as PM2.5, were well above nationally determined daily safe levels of 35 micrograms per cubic meter in each of the cities. New York’s Metropolitan Transit Authority (MTA) system had 251 micrograms per cubic meter, followed by Washington DC with 145 micrograms per cubic meter. Philadelphia was, comparatively, the cleanest system, but still exceeded the limit beyond which serious health risks are exposed.
“New Yorkers in particular should be concerned about the toxins they inhale,” said study co-author Terry Gordon, professor at the Grossman School of Medicine at New York University, the research having revealed that the concentrations of hazardous metals and organic particles were anywhere. two to seven times higher than city outdoor air samples.
Christopher Street, a Manhattan station that connects New York and New Jersey, had an incredible particle pollution level of 1,499 micrograms per cubic meter, about 77 times higher than air pollution. This is a level of pollution more commonly found near a large forest fire or during the demolition of a building, the researchers said.
“It was the worst pollution ever measured in a metro station, higher than some of the worst days in Beijing or Delhi,” said Gordon, who said he was so amazed by the readings on his instruments that he had to ask his colleagues to do repeat tests. to make sure the numbers were correct. “It just wasn’t believable. My colleague went there and his airways felt tight after about an hour.
The researchers calculated that a person taking a typical trip to and from Christopher Street increased their risk of an adverse cardiovascular event by 10%. But the station wasn’t the only one with high airborne toxins, with Broadway in Boston, Second Avenue in New York, and 30th Street in Philadelphia among the most polluted stops in the northeastern United States. “People should be very alarmed at these high levels,” Gordon said.
Subway systems typically carry millions of people in US cities, with the New York MTA, the largest in the country, carrying 5.5 million people around New York City each day in 2019. Subway use has increased plummeted during the coronavirus pandemic, however, with many of the commuters remaining in those essential frontline jobs.
Analysis of air samples shows that the pollutants were primarily composed of iron and organic carbon, a chemical produced by the decomposition of fossil fuels or by decaying plants and animals. The latter, when inhaled, has been linked to an increased risk of respiratory disease, lung cancer and heart disease. It is not entirely clear why pollution in subways is worse than that above ground, although the open air can dilute and remove some of the fumes from cars and trucks while subway stations are often poorly ventilated.
Gordon stressed that more research is needed to determine the exact impact on the health of commuters and transit workers, who spend long periods at polluted stations. The researchers also plan to further explore the exact sources of the pollutants, which can range from the exhaust emitted by diesel locomotives to dust extracted from the remains of dead rodents.
“This is an important contribution, especially to our understanding of the disproportionate burden of air pollution faced by low-income communities and communities of color,” said Gretchen Goldman, research director at the Union of Concerned Scientists, who did not participate in the study. , which was published in Environmental Health Perspectives.
“As the scientific community strives to better understand the exposure and potential health effects of urban air pollution, I hope local decision makers will use this valuable work to inform how best to address inequalities. racial and socioeconomic issues of exposure to air pollution in the United States. cities. “
[ad_2]
Source link