Airborne Metal Pollution Increases the Risk of Mortality

Exposure to airborne metal pollution heightens the risk of natural-cause mortality, according to a study conducted by the Barcelona Institute for Global Health (ISGlobal) who published their results in Environmental International.

“There have been very few studies on the health effects of airborne metal pollutants, partly because of technical limitations, such as the lack of stations measuring air pollution,” said Bénédicte Jacquemin, ISGlobal and INSERM researcher and last author of the study in a press release. “We thought that moss, because of its capacity to retain these metals, would be a useful tool for estimating the atmospheric metal exposure of people living in rural areas.”

To conduct this study, researchers analyzed data from 11,382 participants of the Gazel cohort, a biomonitoring program established in 1989 that obtained exposure estimates across France. In the present study, the baseline was set as January 1996, to reflect the initial date when biomonitoring-based air pollution data became available. The data on mosses was acquired from the BRAMM database, which comprised surveys from four years (1996, 2000 2006, 2011). These respective surveys measured 13 different metals: Aluminum (Al), Arsenic (As), Calcium (Ca), Cadmium (Cd), Chromium (Cr), Copper (Cu), Iron (Fe), Mercury (Hg), Sodium (Na), Nickel (Ni), lead (Pb), Vanadium (V), and Zinc (Zn). The researcher’s distinguished between airborne metals of a natural origin and those an anthropogenic origin. They used Cox models with confounder adjustment at individual level to estimate exposure between metals and natural-cause, cardiovascular, and respiratory mortality.

Airborne Matter a ‘Key Component’ in Mortality

According to the results of the study, between 1996-2017 1,313 deaths occurred in the Gazel cohort, of which 181 were cardiovascular related and 33 respiratory related. Overall, the study found that exposure to the anthropogenic metals was linked to an augmented risk of natural-cause mortality (HR=1.16) while natural metals were not associated with increased mortality.

“Our results indicate that the metals present in the airborne particulate matter could be a key component in the effects of air pollution on mortality”, continued Jacquemin. “It is important to bear in mind that the people we included in this study live in rural areas far from major urban and industrial centers and road networks. This means that they are very likely to be exposed to lower levels of air pollution than people living in urban environments, which gives us an idea of the seriousness of the health effects of air pollution, even at relatively low levels of exposure.”

Jacquemin added that these “findings support our hypothesis that moss bio-monitoring can be a good complementary technique for identifying the toxic components in suspended particulate matter.”


Source: Environment International, EurekAlert