In the past year, stricter standards for perfluorinated compounds have been proposed in North America and Europe. They were prompted by studies showing that these molecules commonly used by industry have health effects at much lower concentrations than expected. A new study confirms this impact on the effectiveness of vaccines.
“The increased risk of cancer with perfluorides took place in particularly contaminated environments”, explains Sébastien Sauvé, a chemist at the University of Montreal who has just published another study on the presence of perfluorides in drinking water in Quebec. “With studies on vaccines, we are talking regarding perfluorinated levels that we find very often. »
Discovered in the 1940s, perfluorides are very resistant, which is positive for industrial aspects, but allows them to accumulate in the environment and living organisms without being degraded. They are notably used in stain repellents, anti-adhesives and high performance fire-fighting foams.
The meta-analysis of 14 studies on the impact of perfluorides on the efficacy of vaccines shows that if the concentration of perfluorides in human blood is doubled, the efficacy of certain vaccines decreases by 5%. Published in February in the journal Environment Internationalit was carried out by researchers from the public and private sectors on behalf of the company 3M, which has just announced that it will stop using perfluorides by 2026.
This 5% drop concerns the presence of T lymphocytes, the soldiers of the immune system. Can it have a clinical effect?
If we see an impact on a molecule, with only a doubling of the blood concentration of perfluorides, that means that there is probably an impact in other parts of the immune system.
Sébastien Sauvé, chemist at the University of Montreal
David Andrews, a biologist from the American NGO Environmental Working Group who has just published a report on perfluorides in wildlife, adds that several studies have confirmed that these molecules affect the immune system of animals, without however showing a clinical effect.
Parkersburg
The perfluorinated blood concentration depends a lot on the surrounding contamination. The C8 study, which follows the health of populations affected by perfluorinated spills near a factory in Parkersburg, West Virginia, reports blood levels 10 to 100 times higher than in the average population. This contamination inspired the film Dark Waters with Mark Ruffalo.
The new study from Environment International is important because the first studies on the effect of perfluoridants were done in the Danish Faroe Islands. “There is a lot of consumption of fish, especially pilot dolphins, in which there is bioaccumulation of toxic substances because they are predators,” says Marc-André Verner, a toxicologist from the University of Montreal who studies perfluorides.
So a meta-analysis of several studies on vaccines confirms that this is a real effect.
Marc-André Verner, toxicologist at the University of Montreal
Studies from the Faroe Islands reported a four times greater effect of perfluorides on vaccine efficacy.
Potable water
M. Sauvé’s study, published in mid-February in the journal Water Research, also illustrates the great variability of exposure to perfluorides. Thus, 5 of the 376 municipalities studied had perfluorinated levels exceeding a standard proposed in Canada for drinking water, 30 nanograms per litre. There were peaks exceeding 100 ng/L in Val-d’Or and 60 ng/L in Saint-Donat.
Val-d’Or has also stopped getting supplies from a particularly problematic well, according to Mr. Sauvé.
But if we take a standard from the US government’s Environmental Protection Agency (EPA), which proposes a value of less than 1 ng/L to avoid any health risk, only 5% of the Quebec municipalities studied pass the test, notes Mr. Sauvé.
The Montreal chemist has also decided to equip himself with a household filter to remove perfluorides from tap water, following noting that Montreal water contains perfluorines up to 13 ng/L. Even bottled water is not perfluorinated-free: a study published in 2018 in Science of the Total Environment by M. Sauvé showed that the levels might go up to 5 ng/L.
Learn more
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- 15 000
- Number of perfluorinated products on a list filed by 3M in the State of Maine
SOURCE : Université Northeastern