What negative effect can plastics have when they accumulate in surface water?

When plastics accumulate in surface water, one of the most concerning negative effects is their ability to accumulate harmful chemicals. Plastics can adsorb toxic substances from the surrounding water, such as heavy metals and persistent organic pollutants. This process occurs because the surface of plastics provides a large area for these chemicals to adhere to. As a result, when organisms come into contact with or ingest these plastic pieces, they can inadvertently consume the toxic substances that have accumulated on them.

This presents significant risks to aquatic life. Small fish or invertebrates may mistake microplastics for food, leading to ingestion. The transfer of these harmful chemicals through the food chain can result in higher trophic levels being affected, including larger fish and even birds and mammals that rely on aquatic species for sustenance. This bioaccumulation can result in detrimental health effects on wildlife and may ultimately impact human health as well through consumption of contaminated fish or water sources. Thus, the accumulation of harmful chemicals due to plastics in surface water is a critical environmental concern that needs to be addressed.