The Problem with Microplastics
Scientists think that about 10 percent of all plastic, which includes plastic bags and bottles, ends up in the ocean. The attributes that make plastic a useful material for a large number of products are its light weight and the strong chemical bonds in its internal structure, which make the material durable. Because plastic by itself is less dense than water, it floats along the ocean surface where it is continuously exposed to ultraviolet light from the Sun, which has the effect of loosening its chemical bonds. Ocean waves smash these weakened pieces of plastic against each other, and they are broken down into smaller and smaller pieces, eventually creating vast numbers of microplastics (pieces less than 5 millimeters across) that disperse throughout the water.
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