Literature Review on Residues of Anticoagulant Rodenticides in Non-Target Animals

Anticoagulant rodenticides are the principal means of controlling pest rodents in the Nordic countries. Due to the intrinsic properties of second generation anticoagulants, i.e. extremely slow elimination from the body and high toxicity, they are prone to accumulate in the non-target species which consume poisoned rodents. Despite wide use there are no published studies on occurrence of residues of anticoagulant rodenticides in the non-target animals in the Nordic countries. This review of publicly available studies was aimed to find out which anticoagulant substances are found and in which species. The concentrations are reported as well as the proportion of exposed animals. We have further compiled a list of species that could potentially be exposed to anticoagulant rodenticides in the Nordic countries. The review shows that anticoagulant residues have been found everywhere they have been measured and secondary exposure to second generation anticoagulants is common among certain avian and mammalian predators. The results call for initiation of measurements of anticoagulant rodenticides also in the Nordic countries.