Air pollution could increase brain tumor risk by 10%

Pulmonary infections, lung cancer, respiratory and cardiovascular diseases… health risks of exposure to urban pollution are well known. To this list could be added that of brain tumours, according to a Canadian study, the first to make the link between ultra-fine particles and brain cancer.

This study, published in early November in the journal Epidemiologytheremeasured the spatial variations of ultra-fine particles in two major Canadian cities (Montreal and Toronto) and examined the health data of 1.9 million adults from the Canadian census cohorts on health and the environment between 1991 and 2016. Pollution levels in the cities studied ranged from 6,000 to 97,000 per cm³.

A 10% increased risk

A total of 1400 cases of brain tumors were identified during the follow-up period (25 years). Each increase of 10,000 ultra-fine particles per cubic centimeter was positively associated with the incidence of brain tumors for every 100,000 people exposed, a 10% increased risk.

“Environmental risks like air pollution are not very important, their importance comes from the fact that all members of the population are exposed. So when you multiply these small risks by a large number of people, suddenly there can be a lot of cases”, explains to the English newspaper The GuardianScott Weichenthal, researcher at McGill University (Montreal) and lead author of the study.

“Environmental fine particles may represent a previously unrecognized risk factor for incident brain tumors in adults. Future studies should aim to replicate these results given the high prevalence of exposure in urban areas,” the scientists conclude.