COVID-19 Therapies in Brazil: Should We Be Concerned with the Impacts on Aquatic Wildlife?

Abstract

The use of unproven COVID-19 drugs has seen a massive increase in recent months in Brazil. Chloroquine (CQ), hydroxychloroquine (HCQ) and ivermectin (IVM) are among the most politically promoted and sold drugs. As a result, an increased demand for these pharmaceuticals has been observed across the country with sales increase by more than 50% in comparison to 2019. In a country where only 46% of domestic wastewater is treated, what can we expect from the effects of these drugs and their metabolites on aquatic wildlife? The environmental fate and ecotoxicity data for IVM indicate varying degrees of toxicity to aquatic invertebrates and the potential to accumulate in several aquatic organisms. The CQ compound was classified as harmful to aquatic organisms and may cause long-term adverse effects in the aquatic environment. As for HCQ, it has been tagged as posing insignificant environmental risks in the pre-pandemic scenario despite its environmental persistence. Fragile Brazilian biomes, such as the Amazon (North region), Caatinga and coastal region of the Northeast and the Atlantic Rainforest (Southeast region) are of particular concern given the high incidence of COVID-19 cases in these areas. The large-scale use of unproven drugs in response to the pandemic may add undue weight to the increased volume of pharmaceuticals entering the environment, leaving the local biota vulnerable to the harmful effects of these contaminants. A nationwide coordinated response is urgently needed to monitor the levels and investigate the impacts of these emerging contaminants. This article is protected by copyright. All rights reserved.