Abstract

Anticoagulant rodenticides (ARs) are generalist toxicants that have lethal and sublethal effects on non-target species, leading to an impact on wildlife conservation due to exposure and bioaccumulation of these substances. However, in Colombia, little research has been conducted on this environmental issue. This study evaluated the use of ARs in Colombia from an ecological and regulatory perspective. First, the study analyzed the usage patterns of ARs in public health in the urban area of Medellín over a six-year period. It also evaluated the potential impact of ARs applied on the city's Main Ecological Structure (MES) and the predator species that may be indirectly affected. Additionally, the study analyzed compliance with regulations on the sale and use of ARs in Colombia, specifically for products marketed online. A Hotspot Analysis was conducted to determine the potential risk of the MES and the predators selected to be exposed to ARs. Afterwards, and overlapping of ARs application sites with Medellin’s biodiversity hotspots were quantified to determine the extent of interaction. The ecotoxicological information of the ARs commercialized online in Colombia was characterized, and it was verified whether they complied with the necessary sanitary and environmental national regulations. Between 2016 and 2022, over 3 million grams of brodifacoum, were applied in the urban area of Medellín and critical ARs hotspots were identified. The use of ARs has significantly increased the doses and number of application sites each year. More than half of the points (51.13%) where ARs were applied were within the MES. The Strigiformes order present the greatest risk of indirect exposure to ARs. Currently, many AR products lack ecotoxicity studies for non-target species and fail to adequately inform consumers of the potential environmental impacts resulting from the use of these poisons. To gain a better understanding of the prevalence, transfer routes, and possible acute and chronic effects of ARs, toxicological studies should be conducted on the urban fauna of Medellín, with special emphasis on predators. It is necessary to increase stringency in the regulation of the marketing of ARs and in the information provided to the end consumer.