In an article published on February 2, 2016 in the scientific journal Nature, journalist Daniel Cressey reports on a new study investigating the impacts of microplastics on the physiology of oysters. The study was published in the peer-reviewed journal Proceedings of the National Academy of Sciences of the United States of America (PNAS) and conducted by researchers Rossana Sussarellu and colleagues from the French Research Institute for Exploitation of the Sea (Ifremer), the Centre of Documentation, Research and Experimentation on Accidental Water Pollution (Cedre), France, and the Institute for Agricultural and Fisheries Research (ILVO), Belgium. The researchers exposed Pacific oysters to water containing polystyrene (PS, CAS 9003-53-6) microspheres (2 and 6 µm in diameter) for two months during a reproductive cycle. The micro-PS was added at a concentration of 0.023 mg·L−1, similar to estimates of microplastics found at the interface between water and sediment, where wild oysters live in the ocean. The researchers found that consumption of microalgae and absorption efficiency were significantly higher in exposed oysters as compared to the controls. Further, exposed oysters produced fewer and smaller egg cells (oocytes) as well as less-mobile sperm. Exposed oysters also had fewer offspring and their offspring grew more slowly. The researchers conclude that ingestion of micro-PS can cause feeding modifications and reproductive disruption in oysters. According to Arnaud Huvet, senior author of the study, this work suggests that “plastic could have long-term effects because oysters are a vital food source for many other animals.” However, it is not yet clear “whether the microplastics that accumulate in oysters could be harmful to the humans that ultimately eat them,” Huvet further notes.
Daniel Cressey (February 2, 2016). “Microplastics damage oyster fertility.” Nature
Gayle S. Putrich (February 5, 2016). “Study: Microplastics damage growth, reproduction of oysters.” Plastics News
Sussarellu, R. et al. (2016). “Oyster reproduction is affected by exposure to polystyrene microplastics.” Proceedings of the National Academy of Sciences of the United Stated of America (published online February 1, 2016).