I have really got interested in microplastic when I attended the Zero Waste Fairs in my hometown. Before that yes, I was aware of its existence, but I never gave too much of a thought regarding its origin or, perhaps more importantly, its consequences on the water habitat. And do not let the name mislead you...microplastic might be tinny tiny plastic particles that are less than 5mm but its presence has huge impact on the aquatic ecosystem.
Before we discuss the threats to the environment posed by the microplastic, let's first define what exactly microplastic is and what its pathways to the marine environment are. The term microplastic includes all plastics smaller than 5 mm. These may be of primary origin, in the form of industrial elements such as scrubbing microbeads or synthetic fibres washed out from clothing during laundering. The study conducted by Julien Boucher and Damien Friot, that quantified microplastic leakage, showed that primary microplastic can in fact be the major source of plastic pollution in the ocean. Secondary microplastics originate from the fragmentation of larger plastic items into smaller plastic elements once exposed to marine environment. Secondary microplastics are also a result of poor waste management such as discarded plastic bags or lost fishnets. The vast majority (98%) of microplastic, however, is lost in land based activities such as laundering or... driving! When you drive, your tyres push down on the road (so as road pushes up on the car -> kinetic frictional force) with great force that causes abrasion. This in turn leads to loosing of the plastic elements.
So how does microplastic enter the water? The main pathways are through road runoff (66%), wastewater treatment systems (25%) and wind transfer (7%) (IUCN Study). Once in the water microplastic particles can either float or sink. It depends on their density and total weight. Polypropylene, for example, is lighter than the seawater and will widely disperse across its surface. Acrylic, on the other hand, is denser than seawater and will eventually accumulate on the ocean floor, from there entering the food chains. Because of the fact that the release of microplastic is not very obvious, the consequences of a persistent ignorance are much more dangerous. Plastic waste encountered in the form of large, visible pieces is easier not only to spot and tackle, but also bring society's attention to the global problem of water pollution thanks to the powerful visuals such as photos and videos. The negative impact of microplastic has been long neglected but may also have far reaching consequences.
Let's begin with a simple: IT DOES NOT BELONG THERE. As microplastic enters the food chain, its existence threatens the ecosystem. Studies have shown that microplastics in the marine environment have an impact on organisms of all trophic levels— worms, fishes, sea turtles, birds, and mammals (Wright et al. 2013; Lusher 2015). What is interesting is that many organisms not only confuse microplastics with food but also selectively feed on them in place of food (Moore 2008). Since plastic cannot be digested but takes a large part of stomach volume, the feeling experienced can be confused with that of satiation. It may stop the organisms from searching for food and consequently decrease the growth and reproductive rates. What is more, if a plastic particle blocks the gastrointestinal tract it may lead to an immediate death. The consequences for humans stem not only from the fact that consuming the fish, we also consume the plastic it can carry. More dangerous is the ability of plastic to attract highly toxic substances from the environment which can bind to the particles and THEN get consumed.
The invention of plastic changed our lives forever. Above all it simply offers hassle-free solutions (plastic food storage), increases our comfort (transport) and satisfies more superficial needs (use of plastic in clothing and microplastic beads in cosmetics). However, our lives made easier come at a great cost. It affects our planet in so many negative ways, yet we are still resistant of letting it go. Of losing the comfort. In that sense going out of your comfort zone has a whole different meaning. By taking smart, conscious decisions, we not only respect Mother Earth but OURSELVES. It is a high time to realize it affects the whole planet which, in fact, we are only a part of. It accomodates much larger group of living organisms and animals for which it is also a HOME. Home upon which we all depend. We talk about sustainable development a lot but we tend to forget that it is actually our planet that sustains our lives. The best we can do it to take a good care of it.
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