“More than 22 million pounds of plastic ends up in the Great Lakes every year!” -

https://www.rit.edu/news/researchers-study-plastic-pollution-great-lakes

Where Does Plastic Pollution Come From?

Plastic enters the environment in many shapes and sizes, through many different routes. Some examples include intentional littering and dumping, or accidental littering such such as trash blowing out of you trash can, car, garbage trucks, and dumpsters. Plastic items, such as plastic bags, food

wrappers, bottles, and cigarette filters, are often littered on the ground or thrown into the street. When it rains, the plastic waste is washed into the storm drain system and eventually ends up in the waterways. 

Plastic in the Great Lakes doesn’t accumulate in ‘great garbage patches’ as it does in the oceans. The highest concentration of plastic pollution is found near cities like Rochester and in locations where strong winds and currents push floating plastic to the shore.

What Happens Once it Enters the Environment?

Different types of plastics are made from different chemicals with different additives. These differences influence what happens to plastic in the environment and how it impacts plants and animals. Some plastic will float at the surface of the water while more dense plastic will sink to the bottom. Over time, the plastic waste builds up and harms aquatic life, our drinking water quality, and our community.

Once in the environment, plastic debris changes. Macroplastics (>5 mm) can weather and break into smaller and smaller pieces, becoming microplastic (<5mm) through wave action, sunlight, and animal and plant activity. Microplastics can be found as spheres, fragments, fibers, foams, and films that come from a wide array of sources, including clothing, turf fields, tires, cosmetic products, and materials used in the fishing and packaging industries. Plastic debris may also absorb toxins from the water, and is colonized by small aquatic organisms, such as bacteria and algae.