- March 22, 2016 - Biodôme : Scientific research
A lighter dropped carelessly on the ground, an empty bottle left by the side of the road, a grocery bag caught by the wind – events that are seemingly harmless, but too often repeated. All that plastic is there to stay, because it’s everlasting. It breaks up into increasingly smaller pieces until it becomes “microplastic”.
The plastic that ends up in the ocean does a lot of damage. We know the horrors of seabirds, whales and turtles who’ve died from accidentally swallowing plastic objects. Now a new threat is taking shape in our oceans, the threat of microplastics.
Origin of microplastics
Microplastic can have numerous origins. According to oceanographer François Galgani, 90 percent of it will have come from the fragmentation of bigger pieces.
But new sources continue to be identified. For example, in recent years it’s been discovered that plastic microbeads less than 1 mm in size were added to a number of cosmetic products as exfoliating agents. Once the products were used, those microbeads ended up unchanged in our waterways. By chance in 2013, a team from McGill University found them all over the St. Lawrence River sediments. Opinions about their origin differ, because these microbeads are also used as basic material in the plastics industry and could therefore be the result of factory discharges.
Can our morning wash now be considered an act of pollution? In the Netherlands, the Beat the Microbead movement is advocating the replacement of plastic microbeads with natural products (such as apricot-kernel derivatives). The finger is also being pointed at our laundry as a source of plastic microfibers (polyesters, nylon, etc.).
Confetti that kills
Small marine animals that live in or near sediments naturally ingest clay or fine sand that is later excreted with the rest of their waste. But what happens with microplastics?
An abundance of synthetic fibers in the intestines can easily create a kind of stopper that slows down or even blocks the passage of food.
Even more worrisome is the ability of plastics to attract and concentrate great quantities of toxic products (PCB, BPA, etc.) present in the water. It’s been demonstrated that those products can be transferred from microplastic to an animal’s tissues, and damage its health. Worse still, these contaminants can then climb the food chain, getting more and more concentrated….until they reach us.
What will be on our plate in the years ahead? A lot of studies remain to be done on that subject, but as a precautionary principle, let’s stop feeding that plastic soup before it ends up on our menu.
