Andrew Lewin interviews Joseph Barnes, a recent Master's graduate from American University, about his research on microplastic behavior in the Potomac River.  They discuss the abundance of microplastics based on seasons and the presence of organisms, as well as how microplastics are used within the ecosystem. Tune in to learn more about this important topic and how we can protect the ocean from the impacts of microplastics. Link to Joseph's paper: https://doi.org/10.1016/j.heliyon.2023.e23239 Follow a career in conservation: https://www.conservation-careers.com/online-training/ Use the code SUFB to get 33% off courses and the careers program.   Facebook Group: https://bit.ly/3NmYvsI Connect with Speak Up For Blue: Website: https://bit.ly/3fOF3Wf Instagram: https://bit.ly/3rIaJSG Twitter: https://bit.ly/3rHZxpc  Joe is a passionate advocate for addressing the issue of microplastics and is known for his enthusiastic and fiery approach. The podcast host acknowledges Joe's dedication and describes him as someone who always brings the fire when discussing microplastics and plastics in general. Joe's desire to make a difference and contribute to solving the microplastics problem is emphasized. The host expresses excitement about Joe's career and looks forward to having him back on the podcast multiple times to discuss his work. It is evident that Joe's commitment to addressing microplastics is unwavering and his passion is palpable. The podcast host expresses genuine excitement about Joe's career and expresses a desire to follow his journey and invite him back on the show multiple times to delve into his work. This indicates that Joe has been a valuable guest on the podcast, sharing valuable insights and expertise, likely related to microplastics. The host appreciates Joe's passion for addressing the microplastics issue and his determination to make a positive impact. They anticipate that Joe will continue to make significant contributions in his field, and they are eager to continue featuring his work on the podcast. This highlights Joe's high regard and expertise in the field of microplastics. In this episode, the host Andrew Lewin introduces the topic of microplastics and focuses on their behavior in rivers. He acknowledges that there is still much research needed to fully understand how microplastics behave in the ecosystem and how organisms interact with them. To shed light on this topic, he invites Joseph Barnes, a recent graduate from American University, who conducted a research project on microplastic behavior in the Potomac River in Washington. According to Barnes, microplastics have the ability to bioaccumulate throughout the food web. This means that they can be ingested by algae, which are then consumed by invertebrates, and so on. As microplastics move up the food chain, they can become a significant problem. Barnes suggests that if mammals or fish in the river show a high accumulation of microplastics or remnants of microplastics in their systems, it could indicate a concerning level of contamination. Lewin also highlights the unique nature of microplastics in rivers compared to other sources of pollution. While discharges from industries are often regulated and controlled point sources, microplastics are less predictable. They can originate from various sources, making it challenging to determine when and where they will enter the river. Barnes's research focused on studying the interaction between microplastics and microorganisms in the river, rather than identifying their specific sources. Overall, this episode delves into the behavior of microplastics in rivers and emphasizes the potential risks they pose to organisms within the ecosystem.