Aquatic Microplastic Research—A Critique and Suggestions for the Future

While there are numerous papers on microplastics (mps) being published every week, there is a need for improvement for the field to mature. The papers reporting numbers found in water bodies cannot be compared because there are no standard methods for collection and analysis. It is clear that using nets for sampling misses most of the microfibers, which are the most abundant form when whole water samples are analyzed, and that microscopic identification has a very high error rate compared to chemical analytical equipment which can also identify the polymers. It is clear that most animals studied eat mps; we should learn what attracts the animals to the mps and what proportion pass right through and are defecated vs those that move into the tissues. It is considered that mps are a vector for transfer of toxic chemicals into the food chain. Let us investigate to what degree what proportion of contaminants are removed in the digestive system vs. staying bound tightly to the mps. Experimental studies should also use environmentally relevant doses and the shapes and sizes of mps that are most abundant in the environment.