What is microplastic
We all know that plastic is a problem. We use articles like plastic bottles or bags once or a handful of times and then throw them out. However, what has only begun to become clear in the past few years, is that there is also a consequence of plastic that is harder to see. Tiny pieces of plastic (5 mm or smaller) are termed microplastics, and just because they are smaller doesn’t mean that we should ignore them. They have disastrous consequences for health of human and nature, not to mention that the plastic could remain in the water forever!
Microplastics can be categorized by their source. There are two main types, primary and secondary. Primary microplastics are purposefully made to be that size, while secondary microplastics are bits of plastic that break down from larger pieces. There is another group that has only recently been discovered, that come from the human use of objects.
Primary microplastics were created by the manufacturer to be a certain tiny size for a particular purpose. The one that you have probably heard about the most are microbeads. They are little plastic spheres used in face washes, cosmetics, and toothpastes to exfoliate or scrub. They are usually made out of polyethylene (or polypropylene, polyethylene terephthalate, or nylon), so look out for these words when you buy products at the drugstore. Traditionally, natural substances like ground almonds, salt, or oatmeal were used, but they started being replaced by plastic about 50 years ago. Perhaps surprisingly, we only started learning about their negative consequences in the past few years. Microbeads have gotten a lot of media attention recently, and several countries have banned them, including the US with the Microbead-Free Water Act of 2015. Unfortunately, they only make up 2% of total microplastics released. Microplastics are also used for air blasting technology. Little bits of plastics (usually acrylic, melamine, or polyester) are blasted at a high pressure at machines, engines, or ship hull to get rid of paint or rust. They are reused until they aren’t effective so they can become contaminated with heavy metals. Microplastics are also used in biomedical research for various techniques.
Larger pieces of plastic can break down over time and release these small pieces into the environment. Weathering, such as from waves, sunlight, or other physical stress, breaks the plastic into smaller pieces. Usually, it originates from waste that wasn’t managed properly. For example, the waste in the “Garbage Patches” degrade into smaller pieces, and there is a lot of trash there! Plastic bags and fishing gear are some examples of common garbage that break down. These microplastics usually have more variable shapes.
Literatures in Microplastics
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- The Guardian, Plastic fibres found in tap water around the world, study reveals. 2017. http://www.theguardian.com/environment/2017/s ep/06/plastic-fibres-found-tap-water-aroundworld-study-reveals. download 2. Plastic fibres found in tap water
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