Based on research, long-term exposure to air pollution can increase the risk of autoimmune diseases.
Particulate exposure is linked to stroke, brain cancer, miscarriage and mental health problems. A global review published in 2019, concluded that almost every cell in the body can be affected by dirty air.
Now, researchers at the University of Verona have found that long-term exposure to high levels of air pollution is associated with an approximately 40% higher risk of rheumatoid arthritis, a 20% higher risk of inflammatory bowel diseases such as Crohn's and ulcerative colitis, and a 15% higher risk. connective tissue diseases, such as lupus.
The study, published in the journal RMD Open, retrieved comprehensive medical information on 81,363 men and women in an Italian database that monitored fracture risk between June 2016 and November 2020. About 12% of them, were diagnosed with an autoimmune disease during this period.
Quoted from The Guardian, Thursday (17/3/2022) each patient is connected to the nearest air quality monitoring station via the postal code of their residence.
This study analyzes the average long-term exposure to fine particulate matter (known as PM10 and PM2.5), generated by sources such as vehicles and power plants. Concentration levels of 30µg/m3 for PM10 and 20µg/m3 for PM2.5 are the thresholds generally considered hazardous to human health.
The study concluded that overall, long-term exposure to particulates above this level was associated with, respectively, a 12% and 13% higher risk of developing an autoimmune disease.
"This study further supports evidence demonstrating a link between exposure to air pollution and immune-mediated disease," said Felicity Gavins, director of the Center for Inflammation Research and Translational Medicine at Brunel University London, UK.
But he cautions against concluding that dirty air causes this condition. "Whether exposure to air pollution specifically causes autoimmune disease is controversial, although there is no doubt that there is a connection," he said.
He also said more research was needed to determine why some regions of Italy experienced such high growth in autoimmune conditions, and to see the impact of secondhand smoking on those findings.
The researchers admit their findings do not prove a causal relationship and that other factors may play a role, including a lack of information about when symptoms of autoimmune diseases begin. Another note, the study participants consisted mostly of older women who were at risk of fracture.
However, air pollution has been linked to immune system disorders, and smoking, along with fossil fuel emissions, as a predisposing factor for rheumatoid arthritis, said Dr Giovanni Adami, co-author of the report and a rheumatologist at the University of Verona.
"WHO has recently identified air pollution as one of the greatest environmental risks to health. Our study provides new evidence of an association between autoimmune diseases and exposure to air pollution. In addition, there are strong biological reasons to support our findings. However, a causal relationship effects are difficult to prove. Indeed, it is unlikely that a randomized controlled study could be conducted on such a topic."