New study links toxic pollutants with high cholesterol among Inuit

Because of what they eat, beluga meat is high in PCBs, which, in turn, are passed on to Inuit who eat the maktaaq. The same is true for the meat and fat of ringed seals, narwhal and polar bears. (FILE PHOTO)

Once again the health of Inuit appears to be under threat from something that people in the North can’t see and didn’t cause, but which is a menace that’s likely to intensify as the Arctic warms.

New research published this month in the online Environmental Research journal points to yet another disturbing link between toxic pollutants in the Arctic and potentially damaging health conditions among Inuit.

These pollutants, banned in 2001, are still present in the Arctic environment, where they’re seen as responsible for a variety of harmful impacts on the health of people and animals.

Researchers from the University of Ottawa studied data from the Inuit Health Survey to see if polychlorinated biphenyls or PCBs, which were used for decades in hundreds of industrial applications, were associated with an increased risk of harmful cholesterol among Canadian Inuit.

Some PCBs have been banned since 2001, when the Stockholm Convention required countries to reduce or eliminate their use, but traces of these PCBs and of newer chemicals are still widely found in the Arctic.

The recently published study was based on health data gathered from more than 2,500 Inuit who participated in the Inuit health surveys of the last decade in Canada’s eastern Arctic.

After looking at the complete survey results, the researchers found that PCBs were associated with the prevalence of high levels of LDL cholesterol in more than 700 participants.

Not all cholesterol is bad. The waxy, fat-like substance is found in all your body’s cells, and is used to make hormones, vitamin D and substances that help you digest foods.

However, a buildup of LDL cholesterol is considered bad, as it can clog your arteries, putting you at a higher risk for cardiovascular disease, including heart attacks.

The researchers noted that it has generally been thought that Inuit have low risk of cardiovascular disease because omega-3 fatty acids found in traditional marine-based diets are thought to add some protection.

But the Inuit diet today “does not seem to provide full protection against cardiovascular morbidity,” they stated.

That may be because such a diet of sea mammals can now be loaded with PCBs, which the animals absorb through the Arctic waters and sea life, and are then passed on to Inuit who eat them.

The researchers now want to see to see whether Inuit Health Survey participants with higher PCB concentrations also consumed more poor-quality store bought foods.

Thanks to the Stockholm Convention, levels of PCBs are declining in the Arctic. However, the rate of decline has slowed and increases have been observed for some PCBs, possibly due to the release of PCBS from melting snow and ice as a result of climate warming, the study noted.

And, despite the downward trends, there’s still concern about the impact of PCBs and other organic pollutants on wildlife and humans, scientists say.

Among the participants of the Inuit Health Survey, the mean concentration for PCBs was four times higher than in the general Canadian population, and up to nine times higher for elderly men.

Other studies have revealed these pollutants have impaired the intelligence, reflexes and immune systems of Inuit children.

A study from the Faroe Islands also found exposure to PCBs is associated with deficient immune function in children, reducing the success of immunizations.