Since large-scale production of plastics began in the 1950s, around 5 gigatons (Gt) of plastic waste has amassed in landfills or the natural environment. As they age, plastics become brittle through exposure to sunlight and break down to produce microplastics (and even smaller nanoplastics). It is a well-established fact that microplastics are in our oceans, rivers, and soils. Over the past five years, we have also learned that microplastics are floating in the air we breathe.
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