Impacts of Microplastics as Contaminants in Freshwater Ecosystems and Human Food Chain

Since the beginning of the industrial revolution, people have become more reliant on plastic products due to their versatility, handiness, and low production cost. Different types of plastic are frequently used and discarded on land or simply discharged into aquatic bodies. Major microplastic polymers are polypropylene (PP), polystyrene (PS), and polyethylene (PE), among many others. These polymers are a mixture of chemicals that are used for their manufacturing. Microplastics, in addition to their presence in the environment, have the capacity to adsorb various contaminants, including heavy metals and persistent organic waste, which further enhances their toxicity. These toxic particles have the ability to adversely affect aquatic life. High accumulations of microplastics have not only affected the fauna and flora of the aquatic system, but they could also pose a risk to human health. Freshwater algal species have also been affected by microplastics. Microplastics in aquatic systems also serve as substrates for microorganisms. Invasive and toxic species become part of an ecosystem loaded with microplastics. The potential effects of microplastics in freshwater ecosystems can alter the quality of water. This chapter aims to offer a comprehensive analysis of the impact of microplastic contaminants on various aspects of aquatic ecosystems, including aquatic organisms, flora, water quality, and human well-being. Additionally, it will provide insight into the intricate dynamics of pollutant transportation within different trophic levels of the aquatic food chain.