The effects of nanoplastics, plastic particles that are under 100 nanometers in size, on aquatic life has not been a heavily studied topic, mostly because of the difficulty of studying objects of such a small size. However, a new study from Lund University reveals some hazardous effects that such particles could have on a marine ecosystem.

“We tested how polystyrene plastic particles of different sizes, charge and surface affect the zooplankton Daphnia. It turned out that the size of the nanoparticles that were most toxic to the Daphnia in our study was 50 nanometers,” Karin Mattsson, the leader of the research project, said.

Plastic debris in the ocean mostly comes from urban runoff, and a vast majority of these are food containers and packaging. Not much data has been collected on nanoplastics, mostly due to the difficulty in studying them, however they are potentially the most hazardous. The sources of nanoplastics may include the degradation of larger particles to the nano level and release from products such as cosmetics and sunscreens.

Mattsson and her team studied the impact of nanoplastics on Daphnia, which is food for many other aquatic animals. They observed that the fish that consumed the Daphnia experienced changes in their predatory behavior and poor appetite. Other studies have found that nanoparticles are able to pass through biological barriers such as the intestinal wall and the brain, which may account for these changes in behavior.

“Although in our study we used much larger amounts of nanoplastic than those present in oceans today, we suspect that plastic particles may be accumulated inside the fish. This means that even low doses could ultimately have a negative effect,” Mattsson said.

Although there has been a constant increase in the use of nanoplastics in consumer goods, there is insufficient knowledge about the effects of such plastics on the health of both life and the ecosystem. Such an increase can lead to a huge rise in pollution, no matter how miniscule the particles may be. Even if sunscreen can be a very efficient method of protecting oneself from the harmful effects of UV rays, such products include nanoplastics that end up being consumed and concentrated all the way up the food chain into our own meals.

<Sean Chiang Troy High School 11th Grade>