Kidney failure, skin infections and sepsis now linked to pollution from motor vehicles, wildfires and power plants
Air pollution could be linked to a new set of diseases, including sepsis, kidney failure, urinary tract and skin infection, say scientists from Harvard T.H. Chan School of Public Health. For this, we may have tiny particles spewing out of motor vehicles, coal-fired power plants, and wildfires to blame, says the research team.
Even short-exposure to these small particles, called particulate matter 2.5 or PM2.5, could have a bearing on healthcare and economic costs, according to experts.
The study also provides concrete evidence to strengthen links between this pollutant and other diseases reported in previous studies: heart and lung diseases, diabetes, Parkinson's disease, and diabetes.
Earlier studies have shown that, when inhaled, the particles measuring 2.5 nanometers, can enter deep into the lungs and cause serious health problems.
"The study shows that the health dangers and economic impacts of air pollution are significantly larger than previously understood," says Yaguang Wei, a doctoral candidate at Harvard Chan School and lead author of the study.
Through the study, scientists saw that exposure to PM2.5 had links with diseases, even at levels below the WHO guidelines and the National Ambient Air Quality Standards in the US.
According to the WHO guidelines, PM2.5 levels must not exceed the limit of 10 μg/m3 annual mean. These results raise awareness of the continued importance of assessing the impact of air pollution exposure.
The findings suggest that the WHO guidelines and the National Ambient Air Quality Standards guidelines must be reviewed and updated, explains Francesca Dominici, professor of biostatistics at Harvard Chan School and principal investigator of the study.
In the current study, the team dug deeper by comparing information from records of hospitalization and exposure to the pollutant.
"For this study, we wanted to shed further light on the risks of exposure to short-term air pollution by searching for links between such pollution and all the diseases that are plausible causes of hospitalizations," says Joel Schwartz, professor of environmental epidemiology at Harvard Chan School and senior author of the study.
To test this, researchers scoured data for 13 years. Their first source was Medicare hospital insurance, which helped them get a sense of hospitalizations.
From these insurance claims, the researchers obtained information from more than 95 million adults, aged 65 or older in the United States, from 2000 to 2012. Their second data source was from the US Environmental Protection Agency, which helped them predict daily exposure to PM2.5 levels.
They found 2,050 extra hospital admissions, 12,216 days in hospital, and $31m in care costs for diseases — not associated with the pollutant earlier, including sepsis, kidney failure, urinary tract, and skin infections — with each 1 ug/m3 increase in PM2.5.
However, they explain that these newly-associated diseases represent around a third of the total PM2.5 associated effect, suggesting that current figures for PM2.5 associated illness "might be considerable underestimates".
One major limitation of the study, according to the authors, is that they could not factor in other causes that may have triggered hospital admissions such as smoking, alcohol consumption and drug use. The study was published in BMJ.