COVID-19 estimated to have increased plastics, diclofenac, and triclosan pollution in more than half of urban rivers worldwide

Summary: The enhanced use of protective materials and chemicals during the COVID-19 pandemic has probably increased river pollution, but the effects of country-specific measures on multiple pollutants in rivers worldwide are not well documented. Here, we use an updated, spatially explicit water quality model to estimate the effects of the increased use of hand soap (triclosan), personal protective equipment and packaging materials (plastics), painkillers (diclofenac), and reduced transportation (microplastics from car tires) on river pollution in 10,226 sub-basins worldwide. Model results indicate that, globally, COVID-19 measures increased river pollution with macroplastics by 56%, triclosan by 33%, and diclofenac by 50%. Notably, only microplastics from car tires decreased. We identified priority sub-basins and pollutants across the globe for which water pollution control strategies should consider the impacts of COVID-19 measures. For these sub-basins, our results can inform the development of strategies for ameliorating the impacts of measures taken during the COVID-19 pandemic. Science for society: Globally, river pollution is a growing concern, given its potential impacts on ecosystems. COVID-19 has likely compounded this pollution via an increased use of products such as masks, hand sanitizers, and painkillers. However, we do not have a clear understanding of pollutant types, at which locations pollution might have increased, or the extent of any increase. This hinders the development of pollution control strategies in the worst-affected river basins. Countries encouraged or enforced varying strategies to combat the pandemic; therefore, assessing the impact of these differing COVID-19 measures on river pollution requires models that capture country-specific strategies.