Anticoagulant residues in rat liver: Persistence and secondary hazard to non-target species

In New Zealand, the second-generation anticoagulant brodifacoum has been successfully used in island rodent eradications and is currently applied in some mainland areas to control introduced pests such as brushtail possums (Trichosurus vulpecula) and rodents (Rattus spp.). However, ongoing field use of brodifacoum is under scrutiny because nontarget wildlife can acquire persistent residues. To investigate alternative rodenticides, the persistence of sublethal oral doses of five anticoagulants (brodifacoum, warfarin, pindone, diphacinone and coumatetralyl) in laboratory rats was compared. Diphacinone and pindone had the shortest hepatic half-lives, indicating a shorter-term secondary hazard. A further study compared concentrations of liver residues of the five anticoagulants in laboratory rats after different regimes of bait consumption. These data, alongside available toxicity values, were used to construct a theoretical, conservative assessment of the risk of acute secondary poisoning to New Zealand nontarget birds and mammals.

Author Fisher, P., O'Connor, C. E. and Eason, C. T.
Date 2004-10-19
Year 2004
Secondary title 2nd National Invasive Rodent Summit
Place published Fort Collins
Publisher National Wildlife Research Centre
Pages 9
Control method Baiting
Region NZ