A study of the Institute of Global Health of Barcelona, carried out in almost thirty villages in southern India, has found an association between exposure to air pollution and worse bone health.
Some effects of air pollution on health are well known –lung cancer, stroke, respiratory diseases and much more– but others have less scientific evidence. This is the case of bone health: there are few studies and their findings have not been conclusive. Now, research carried out in India led by the Institute of Global Health of Barcelona (ISGlobal) found an association between exposure to air pollution and worse bone health.
Osteoporosis is a disease in which bone mass density decreases. It is responsible for a substantial burden of disease worldwide and is expected to increase its prevalence due to population aging.
The new study, carried out by the CHAI Project , which coordinates ISGlobal, is published in Jama Network Open. It analyzed the relationship between air pollution and bone health, in more than 3,700 people in 28 villages near Hyderabad, in the south of India.
The authors applied a model developed locally to estimate exposure to air pollution around homes: fine particles (particles suspended in the air with a diameter of less than 2.5 μm, PM 2.5 ) and black carbon (BC).
Participants also reported the type of fuel they use for cooking. This information was related to bone health, evaluated from a type of x-ray that measures bone density –double energy x-ray absorptiometry (DXA). The bone mass in the spine and in the left hip was analyzed.
The results showed that exposure to air pollution, especially to fine particles, was associated with low bone mass. No link was found with the activity of cooking with biomass fuel.
“This study contributes to the scarce and inconclusive scientific literature that associates air pollution with worse bone health,” explains Otavio T. Ranzani, a researcher at ISGlobal and first author of the study.
As for the mechanisms that could explain this link, the researcher points out that “the inhalation of contaminating particles can lead to an increase in bone mineral loss, through oxidative stress and inflammation caused by contamination.”
The annual exposure to PM 2.5 was 32.8 µg/m 3, well above the maximum values recommended by the World Health Organization (10 µg / m 3 ). 58% of the participants used biomass fuel for cooking.
“Our findings add to a growing body of scientific literature that indicates that air pollution is relevant to bone health, in a wide range of exposure levels, including both those found in low- and middle-income countries, such as those in high income,” said Cathryn Tonne , coordinator of the study and the CHAI Project.