Pollution Increases Plastic Concentrations in Marine Organisms

May, 2021 - By SMI

Study on fish specimen from hundred years reveals increase of plastic in their guts since 1950s.

Biologists from Chicago's Loyola University presented a study focusing on the microplastics, which are little fragments of soda bottles, shopping bags, and other items made from plastic broken down to size smaller than 0.2 in (5mm). Recent studies on the effects of these microplastics on aquatic organisms discovered some concerning findings.

Scientists found that microplastics can cause reproductive changes and aneurysms in fish and adversely impact cognitive performance of hermit crab. Studies on possible effects on humans found evidences of microplastics moving through food chain and chances of altering the shape of lung cells.

Understandings on the effects of plastic pollution on marine organisms are improving rapidly due to various modern techniques. Now, they can be used to better understand past plight of creatures. Scientists took museum collection to go back in time and analyze guts of freshwater fishes over the last century. It revealed that not only they are swallowing plastic for decades but also the concentration has skyrocketed in their stomachs in recent years.

The team went to the Field Museum of Chicago where specimens of over two million fish are preserved in alcohol and stored in a collection underground. The research focused on four types of fish specimen that included channel catfish, largemouth bass, round gobies, and sand shiners. These records dated back in 1900 to 2017 and were compared to fresh samples of the same species. There were no traces of plastic until the first half of previous century. However, the concentrations began to surge after the industrialization of plastic manufacturing in 1950s. These plastics were derived from polymers and other synthetic and natural textiles and were found in a fiber form. This significant surge in concentrations is described by scientists as "alarming".