Microplastic pollution is an increasingly important environmental concern, especially in aquatic ecosystems. However, research on microplastics has historically been skewed towards marine systems and large freshwater systems, leading to an incomplete picture of the potential prevalence and scope of this type of pollution. In order to understand the potentially ubiquitous nature of freshwater microplastics, our study focused on 11 small headwater streams in north–central Massachusetts (USA) and a small freshwater fish species, the Blacknose dace (Rhinichthys atratulus). Microplastics were found in all sampled streams. Considerable variation in the number of stream microplastics existed, with concentrations ranging from 0.3 to 45.1 pieces per cubic meter of water. Microplastics were assessed in 14–20 fish from each of five of these streams. The vast majority of all fish had microplastics, with some individuals having over 200 pieces in their digestive tract. The number of fish microplastics was not found to be statistically related to the amount of water microplastics, the length of the fish, or the land use surrounding the streams. Together, these results illustrate that microplastics are prevalent and that small freshwater ecosystems need to be considered when assessing the full impact this source of pollution may have on ecosystems.
Gordon et al. (Sat,) studied this question.