Climate change and microplastic pollution in aquatic ecosystems: ecological and societal consequences

Unsustainable development has led to a global crisis that is exacerbated by climate change.Plastic pollution in aquatic environments poses a significant environmental challenge, negatively impacting water quality, biodiversity, and human health. The progression of climate change, characterized by rising temperatures, altered precipitation patterns, extreme weather events, and sea-level rise, accelerates the fragmentation, dispersal, and persistence of plastics. These processes amplify the impacts of plastic pollution on rivers, estuaries, and coastal ecosystems.In tropical estuarine mangrove forests, for example, climate-driven flooding and salinity changes interact with high levels of plastic waste, creating hotspots of contamination that threaten fisheries and coastal livelihoods (Roebroek et al., 2021) Rivers, estuaries, and coastal waters, as complex and dynamic systems, are influenced by both climatic and non-climatic drivers, highlighting their importance for environmental research and policy. The El Niño Southern Oscillation (ENSO) events, as observed in 2006 and 2017, have been associated with increased nutrient levels, such as ammonia and phosphorus, particularly in the easternmost South American estuarine and coastal region (Dos Santos et al., 2025). Consequently, climate change could exacerbate harmful algal blooms and hypoxia (Glibert, 2017). These processes appear to be characterised by arid periods (La Niña) followed by drastically increased rainfall patterns (EL Niño), which could also promote the dispersal of plastics, particularly micro-and nanoplastics, into aquatic ecosystems.Plastics exert both direct and indirect effects on aquatic fauna and flora, including ingestion, organism toxicity (Carty et al., 2025), habitat alteration, and reduced resilience of ecosystems already under stress. The combined effects of climate drivers and plastic pollution compromise biodiversity, fisheries, and essential ecosystem services (Rillig et al., 2021). Recent studies in Bangladesh indicate that flood events remobilize plastic debris from inadequately managed landfills into estuarine waters, substantially increasing downstream contamination (Roebroek et al., 2021). Similar processes have been observed in the United Kingdom, where coastal landfill erosion threatens to release significant quantities of plastics into estuaries (Brand, 2017). These case studies exemplify global trends, demonstrating that aquatic organisms at higher trophic levels are particularly vulnerable to the combined impacts of plastics and climate-related stressors (Kelly et al., 2025). Furthermore, evidence indicates that top predators in aquatic ecosystems are increasingly contaminated by microplastics through biotransfer within the food web (Melo et al., 2024).The combined effects of climate change and microplastics constitute a significant and escalating threat to aquatic ecosystems. Variations in temperature, precipitation, and extreme weather events intensify river flow, increasing the transport of microplastics into rivers and seas. This sequence of events leads to more frequent algal blooms and hypoxic conditions, thereby amplifying the detrimental impacts of plastics on aquatic organisms. As microplastics transport toxins and pathogens, their risks become closely linked with those of climate change, highlighting the urgent need for integrated monitoring and comprehensive mitigation strategies.Addressing these interconnected challenges requires context-specific solutions tailored to each aquatic environment. Restoration of wetlands, establishment of riparian buffers, and effective nutrient management can improve water quality and support biodiversity.Community engagement and educational initiatives further enhance the effectiveness of these interventions. Such targeted actions are crucial to enhancing ecosystem resilience and fostering sustainable environmental stewardship.Despite growing awareness, large volumes of plastic waste continue to reach aquatic systems daily, especially from densely populated urban regions where inadequate waste management still prevails (Napper & Thompson, 2020). Climate change magnifies these impacts, while political and economic obstacles delay effective mitigation. Petrochemical industries play a powerful role in influencing governments and slowing reductions in plastic production. For instance, lobbying efforts have weakened or delayed single-use plastic bans in several countries, and at the global scale, industry resistance contributed to the breakdown of consensus during the 2025 Geneva negotiations on the Global Plastics Treaty (UNEP, 2025).Without decisive policy, the reliance on fossil fuels and increasing plastic output will accelerate biodiversity loss, intensify socio-environmental inequalities, and compromise global climate and sustainability goals.Given the importance of this subject to Earth's health, the main questions are: What should be prioritized? What specific roles should the aquatic science community play? Building on these questions, it is important to consider not only immediate research needs but also long-term strategies. This comprehensive approach is essential for impactful collaboration and innovation. By fostering interdisciplinary partnerships and embracing technological advancements, the aquatic science community can lead efforts in ecosystem restoration, sustainable resource management, and public education. Prioritizing these approaches will help ensure that scientific knowledge translates into effective policy and meaningful change for aquatic environments.Looking ahead, the aquatic science community should also invest in capacity-building initiatives that support emerging researchers and amplify diverse voices within the field.Establishing collaborative networks with stakeholders, including policymakers, indigenous communities, and industry leaders, will further enhance the relevance and application of scientific findings. By promoting open data sharing and transparent communication, the community can accelerate innovation and respond more effectively to emerging challenges.Ultimately, these efforts will build resilience in aquatic ecosystems and empower society to make informed decisions for the health and sustainability of our water resources.Addressing this dual crisis requires integrated and coordinated action. An Integrated, worldwide, long-term project establishes coordinated global research initiatives that use standardised protocols to assess how microplastic contamination and climate change jointly affect aquatic ecosystems. Such projects should harmonise sampling and analytical methods,Plastic pollution in aquatic environments, exacerbated by climate change, is not just a crisisit's an urgent call to action. Its impacts, from biodiversity loss and fisheries decline to water insecurity and economic costs for coastal communities, are already being felt. The most significant barriers are not only scientific but also political and social.Plastics in sediment have a negative impact on aquatic ecosystems by being ingested by organisms, leading to starvation and physical injury, and by releasing harmful chemicals that disrupt biological processes. These plastics, especially microplastics, can accumulate within the food web and may ultimately enter the human food chain. The persistence of plastics in sediments means that today's emissions will shape aquatic ecosystems for decades to centuries, raising profound questions of intergenerational justice and responsibility. The weight of this responsibility cannot be overstated, as the decisions we make today will have a lasting impact on future generations (Rillig et al., 2021).Overcoming entrenched industrial interests, strengthening governance, and fostering intergenerational responsibility are essential. But these efforts will be in vain without the collective action of all stakeholders. Transforming concern into collective action will be decisive in restoring resilience to rivers, estuaries, and coastal ecosystems and in securing a sustainable future for generations to come.