Air pollution is one of the greatest environmental and health problems of the century. Burning fossil fuels, vehicular emissions and construction are some of the biggest sources of air pollution. These pollutants can be present in the form of tiny airborne particles (not visible to the naked eye) which can penetrate the lungs and the bloodstream, resulting in bronchitis, heart attacks, and other problems.
These pollutants can act as a trigger for people with asthma or other respiratory allergies. Long term exposure to particulate matter in the air can result in heart diseases, lung cancers, and irreversible damage to the nerves, brain, kidneys, liver, and other vital organs. Recent research has also shown that exposure to particulate matter can also result in type 2 diabetes mellitus.
What is particulate matter?
Particulate matter (PM) is a mixture of both dirt, dust, grit and smoke, that form the main components of air pollution. While some particulate matter can be seen through naked eyes, others are microscopic in size. The most commonly found particulate matter include PM10 (particles with a diameter of 10 micrometres or less) and PM2.5 (particles with a diameter of 2.5 micrometres or less). The smaller the size of the pollutant particle, the larger the risk it holds for the human body, as particles with diameter less than 10 micrometres can settle deep into the lungs and can even get dissolved in the bloodstream.
How is air pollution linked to diabetes?
Various research conducted in the past has concluded that exposure to air pollution can increase the risk of developing diabetes.
- A recent study published in The Lancet Planetary Health evaluated the relationship between levels of pollution and the risk of developing diabetes among more than 1.7 million US veterans. These veterans were followed for 8.5 years and none of them had a history of diabetes. The results of the study showed that when the levels of particulate matter 2.5 were between 5 and 10 μg/m3 (micrograms per cubic metre) of air, about 21% of people ended up developing diabetes. As the PM 2.5 exposure increased to 11.9 -13.6 micrograms per cubic meter, about 24% of people developed diabetes.
- A cross-sectional study conducted in Iran from 2006 to 2011 examined 2916 adult participants to determine the relationship between long-term exposure to particulate matter and the prevalence of type 2 diabetes mellitus. The result of the study showed that people who were exposed to PM10 for 5 years were at increased risk of developing diabetes.
- Another cohort study conducted in Hong Kong extended for more than 9 years and concluded that long-term exposure to a high level of PM2.5 can increase the risk of type 2 diabetes.
- A study conducted in Germany concluded that exposure to air pollution for 28 to 91 days can increase the risk of diabetes in people with no previous history of diabetes. They further stated that exposure to pollutants such as sulfur dioxide (SO2) and carbon monoxide (CO) was positively associated with the presence of type 2 diabetes.
Despite all these studies, the reasons for poor air quality causing diabetes is still unclear and research is still being conducted to ascertain the correlation and understand the root cause.
What can be done to protect oneself from air pollution?
There are some simple things that can be done to make sure that we stay protected from the harmful effects of air pollution.
- Try to do your bit to reduce contribution toward vehicular pollution and opt for different modes of transportation. If possible, try using public transport to work. One can walk or ride a bike for nearby places.
- Do not burn the garbage in your garden or surroundings, as it adds on to the pollution.
- People living in cities with extremely poor air quality must avoid stepping out of their house early in the morning as the pollution levels are at a peak during those hours.
- One can use a good quality mask preferably N95, N99 or N100 mask as they can filter out the finest pollution particles.
- Use air purifiers at home to filter out the allergens, toxins and other pollutants from the indoor air.
- Keep your windows closed during morning and evening hours when the air pollution tends to be at its maximum.
- Wear sunscreen while stepping out of the house to avoid any kind of skin damage.
- Take up some form of exercise, such as running up and down the stairs or using a skipping rope, to keep yourself active and healthy.
- People with a family history of diabetes must get their blood sugar levels checked every 3 months.
- Avoid high-fat, calorie-rich food as it can lead to obesity, which is a risk factor for type 2 diabetes mellitus.
Some research has compared the effect of getting exposed to air pollution to eating a high-fat diet, as both resulted in insulin resistance and abnormal body metabolism. It is advised that people living in densely polluted cities, must wear masks, use an indoor air cleaner and keep their windows closed to reduce the impact of air pollution. If they are at a higher risk of developing type 2 diabetes, they must get screened for the condition periodically.