A Review on the Toxicity and Non-Target Effects of Macrocyclic Lactones in Terrestrial and Aquatic Environments

Abstract

The avermectins, milbemycins and spinosyns are collectively referred to as macrocyclic lactones (MLs) which comprise several classes of chemicals derived from cultures of soil micro-organisms. These compounds are extensively and increasingly used in veterinary medicine and agriculture. Due to their potential effects on non-target organisms, large amounts of information on their impact in the environment has been compiled in recent years, mainly caused by legal requirements related to their marketing authorization or registration. The main objective of this paper is to critically review the present knowledge about the acute and chronic ecotoxicological effects of MLs on organisms, mainly invertebrates, in the terrestrial and aquatic environment. Detailed information is presented on the mode-of-action as well as the ecotoxicity of the most important compounds representing the three groups of MLs. This information, based on more than 360 references, is mainly provided in nine tables, presenting the effects of abamectin, ivermectin, eprinomectin, doramectin, emamectin, moxidectin, and spinosad on individual species of terrestrial and aquatic invertebrates as well as plants and algae. Since dung dwelling organisms are particularly important non-targets, as they are exposed via dung from treated animals over their whole life-cycle, the information on the effects of MLs on dung communities is compiled in an additional table. The results of this review clearly demonstrate that regarding environmental impacts many macrocyclic lactones are substances of high concern particularly with larval instars of invertebrates. Recent studies have also shown that susceptibility varies with life cycle stage and impacts can be mitigated by using MLs when these stages are not present. However information on the environmental impact of the MLs is scattered across a wide range of specialised scientific journals with research focusing mainly on ivermectin and to a lesser extent on abamectin doramectin and moxidectin. By comparison, information on compounds such as eprinomectin, emamectin and selamectin is still relatively scarce.

Dung removal by dung beetles (Coleoptera: Scarabaeidae) and macrocyclic lactone use on cattle ranches of Yucatan, Mexico

“…The fact that we observed no change in dung removal amount in the present study does not mean that ML has no negative effect on dung beetle populations. The negative effects of ML on dung beetle species have been confirmed in laboratory studies, for several Old World species (Lumaret, Errouissi, Floate, Römbke, & Wardhaugh, 2012;Wall & Beynon, 2012;Verdú et al, 2015) and one new world species (Pérez-Cogollo, Rodríguez-Vivas, Delfín-González, Reyes-Novelo, & Ojeda-Chi, 2015). And it is likely that field confirmation of the negative effects on dung beetle population requires a longer study period than that used here.…”

Indução de ivermectina na hormese sobre Eisenia foetida durante a vermicompostagem de esterco bovino

“…Por outro lado e como demonstrado na Tabela 1, nas duas primeiras semanas do experimento foi verificada diminuição na taxa de desenvolvimento caracterizada pela redução no peso das minhocas expostas às duas concentrações mais elevadas de IVM. Este evento pode estar relacionado ao mecanismo de ação do fármaco em invertebrados que atuam mediante a ligação irreversível e ativação de canais iônicos dependentes de ligantes, particularmente canais cloretos dependentes de glutamato e receptores do ácido γ-aminobutírico (GABA), resultando em paralisia corporal e disfunção dos músculos da faringe (Lumaret et al, 2012).…”

“…A ivermectina, uma lactona macrocíclica pertencente à classe das avermectinas, é comumente e globalmente aplicada para eliminar ectoparasitas e nematoides gratintestinais de uma variedade de espécies animais; sofre pouca metabolização e é parcialmente excretada de forma inalterada pelas fezes de animais tratados (Lumaret et al, 2012).…”

“…Tem-se demonstrado que a presença de resíduos ambientais de fármacos veterinários, principalmente da classe das avermectinas, afeta organismos não-alvo que habitam os estercos e o solo, levando as agências internacionais de regulação ambiental a emitir alertas sobre o risco de substâncias potencialmente tóxicas excretadas por animais de produção (Lumaret et al, 2012;Blanckenhorn et al, 2013).…”

Merging Wildlife and Environmental Monitoring Approaches with Forensic Principles: Application of Unconventional and Non-Invasive Sampling in Eco- Pharmacovigilance

“…We are unaware of any studies that have investigated the potential exposure of scavenging insects to nonsteroidal anti-inflammatory drugs, or possible secondary exposure/effects to the species that feed on them. In contrast to scavenging insects, a substantial number of studies have examined the repercussions of veterinary agents excreted in livestock animal dung to coprophagous insect species [186,228] which play a key role in maintaining pasture hygiene [229] and productivity, and in cycling nutrients [183]. However, to our knowledge, the potential exposure of these species to NSAIDs has not yet been evaluated.…”