What Are Your Patients Breathing?

Consider the clinical case of a 25-year-old male seen at Boston Medical Center (BMC) while experiencing an acute asthma episode. The flareups were becoming more frequent, he said. After he had been treated and stabilized, he reported that he lived in a low-income neighborhood close to a major highway in old housing stock. Indoors, he was potentially exposed to asbestos, lead paint, and mold. Outdoors, he was certainly exposed to traffic pollution that is closely associated with asthma exacerbations and is a risk factor for developing asthma.
“You can’t necessarily say this patient’s symptoms are clearly due to air pollution,” said Dr. Manijeh Berenji, who specializes in occupational and environmental medicine at BMC, “but you do have enough information for a risk assessment — to say, ‘this person has all these contributing sources to his current respiratory state.’ You can come to a pretty legitimate conclusion.”
The adverse health effects of air pollution will almost certainly become worse as climate change intensifies, researchers say. In New England exam rooms, the health impact of air pollution may show up as more cases of respiratory or cardiovascular distress and more acute episodes.
At a symposium on “Natural Gas Infrastructure and Public Health” at Boston University in January, Dr. Mary Rice, a pulmonologist at Beth Israel Deaconess Medcial Center, presented her team’s research on the local effects of relatively low levels of air pollution. A study in Eastern Mass. showed that healthy adults had clinically meaningful reductions in lung function after a moderate (as opposed to a good) air-quality day, as delineated by EPA standards. Meanwhile, a 2018 Boston study found evidence of air pollution as a risk factor for pediatric asthma.
Fine particulate matter in the air and ozone are known public health hazards. A 2017 study involving more than 60 million Medicare beneficiaries in the continental U.S. found that, the higher the concentration of air pollutants, the higher the chance of an early death.
Particulate matter is associated with serious cardiovascular and respiratory illness and increased mortality — a relationship that is evident even at very low concentrations of ambient particles. Traffic is a major contributor of particulate matter, and traffic pollution is heavily implicated in cardiovascular disease, obesity, and diabetes, as well as respiratory illness.
Climate change is expected to increase concentrations of ground-level ozone, along with more frequent stagnant air conditions, which further raise the ozone risk. Ozone is associated with respiratory illness and chronic obstructive pulmonary disease. The U.S. Global Change Research Program predicts rising hospital admissions and premature deaths linked to ozone.
The health effects of air pollution are most heavily felt by people with pre-existing, chronic medical conditions, as well as the young, the old, and those who work or exercise outdoors.
In addition, research shows that air pollution continues to amplify disparities along racial, ethnic, and socioeconomic lines. Communities of lower socioeconomic status are more likely to live in areas with higher air pollution. In Massachusetts, 555,000 adults and 168,000 children have asthma — a disease more common among racial and ethnic minorities and people living in poverty, compared to the general population.
The U.S. withdrawal from the Paris Agreement, a voluntary international commitment to limiting greenhouse gases, pointed to the U.S. government as a barrier to clean air. Like the air itself, U.S. federal policy on air has stagnated while other countries have continued to finesse their equivalent legislation. The Clean Air Act has been key to reducing air pollution and its associated health risks, but the law has not been updated since 1990.
Meaningful policy change can also take place at the state level. Researchers at the Harvard T. H. Chan School of Public Health calculated last year that two Massachusetts bills aimed at implementing a carbon tax could save 340 lives and generate $2.9 billion in health benefits by 2040, largely from reduced transport and building emissions.