Nontarget and secondary poisoning risks associated with cholecalciferol

Abstract

In New Zealand cholecalciferolcontaining baits are used for possum and rodent control We have assessed the primary and secondary nontarget hazards associated with these baits At 2000 mg/kg cholecalciferol had no adverse effects in ducks but some chickens and canaries died Weta and weka were not affected by eating bait containing cholecalciferol In secondary poisoning studies most dogs and cats fed carcasses of possums poisoned with cholecalciferol were unaffected but repeat exposures for 5 days induced some reversible signs of toxicosis in dogs The most distinguishing feature of cholecalciferol is a lower risk of secondary poisoning when compared with 1080 and brodifacoum

The potential of coumatetralyl enhanced by cholecalciferol in the control of anticoagulant-resistant Norway rats (Rattus norvegicus)

“…Both compounds have been shown to pose a substantially smaller risk of secondary poisoning to owls and other predators than second-generation anticoagulants. 18,19,34 The use of coumatetralyl under the described schedule is associated with comparatively small hazards for mammals, such as ferrets and birds like the barn owl. 17 -20 Generally, the hazards of first-generation anticoagulants and their exposure to non-target and predatory species have received only little attention in recent research when compared with those caused by compounds of the second generation.…”

“…15,16,35 Cholecalciferol, too, poses only a small risk of secondary poisoning, even when used at much higher concentrations in bait than in the proposed combination. 34,36 Therefore, the combination of coumatetralyl and cholecalciferol was suggested for large-scale outdoor use in the management of possums in New Zealand forests. 36 This combination constitutes an alternative, because it may also reduce the risk of secondary poisoning resulting from the use of second-generation anticoagulants in the management of anticoagulant-resistant rats, in particular in rural areas where exposure of owls, raptors and predators cannot be excluded.…”

Technology Advances for Vertebrate Pest Eradication

“…Likewise, a similar re-registration review has been undertaken in Australia by the Australian Pesticide and Veterinary Medicine Authority (APVMA 2008), and in the United States the National Wildlife Research Center (NWRC) completed about 250 studies costing USD$3 million by resubmission of existing suitable data on 1080, zinc phosphide, and cyanide. Cholecalciferol registrations have recently been discontinued in the European Union due to lack of investment, despite the advantages of cholecalciferol's low secondary poisoning risk versus other toxicants (Eason et al 2000). The data requirements of the EU Biocide Directive were deemed excessive, and extremely costly to generate relative to their scientific merit and sales volume by the registrants (Eason et al 2010, Adams 2005, Buckle et al 2005.…”

Trends in Vertebrate Pesticide Use and New Developments: New Zealand Initiatives and International Implications

“…Cholecalciferol (vitamin D 3 ) was developed in NZ for controlling possums (Eason 1991) and is now registered in Feracol ® paste bait, Pestoff DECAL Possum Bait ® , and No Possum ® gel, with Feracol ® paste bait also now used for rodent control. There is low risk of secondary poisoning to dogs, and birds are much less susceptible to cholecalciferol than to 1080 (Eason et al 2000), but current baits are deemed too expensive.…”

“…Cholecalciferol has the advantage of low secondary poisoning risk and low toxicity to birds (Eason et al 2000). Currently available commercial baits contain cholecalciferol at a concentration of 0.8%.…”