Biomarkers in Earthworms

27 pagesSoil-dwelling naturally occurring earthworms (e.g. Lumbricus terrestris) are valuable sentinels in soil pollution monitoring for their ecological role but also because they have shown to be sensitive to environmental contaminants. However, most laboratory studies have adopted epigeic earthworms as models (Eisenia spp.) in acute toxicity testing. In soil chronic toxicity assessment, it is essential to include sublethal responses that can have direct implications on species performance, reproduction and behaviour and thus be of ecological significance. In this sense, some biochemical biomarkers are regarded as early warning signals of further ecological consequences. Amongst those most frequently considered are specific responses to certain chemicals (e.g. metallothionein induction to metal exposure) but also those related to oxidative homeostasis of the organisms because prolonged stress may lead to adverse effects at the individual level (disruption of immune system, altered growth and reproduction). Biomarker measures can be applied in specific tissues, but, for methodological constraints, the consideration of the whole animal simplifies protocols and, once validated, they are informative and integrative. The use of non-destructive tissues (e.g. coelomocytes) that do not require sacrifice, the incorporation of “omic” disciplines and recent technical advances in metabolite identification are all encouraged to be incorporated into toxicity evaluationTo the EU Water JPI-2015 AWARE project (PCIN-2017-067), D. Nos and D. Romano are thanked for their contribution to the projectPeer reviewe