bromfenacoum and diphenadione

Anticoagulant rodenticides are used worldwide to control pest rodent species. However, the risks posed to non-target reptiles have not been well characterized. In this study, 46 giant ameivas (Ameiva ameiva), 39 boa constrictors (Boa constrictor), 33 wood turtles (Rhinoclemmys pulcherrima), and 47 green iguanas (Iguana iguana) were orally dosed with one of two levels of either diphacinone or brodifacoum anticoagulant in propylene glycol solutions. Dosages were derived using daily food intake (DFI) equations, converting DFI to an equivalent anticoagulant bait amount and gavaging the solution volume needed to deliver the quantity of anticoagulant in that amount of bait. Animals were dosed on days 0 and 7 and monitored for a further 7 days for signs of anticoagulant intoxication and differences in behaviors and postures. At necropsy on day 14, animals were examined for thoracic and abdominal bleeding, and both tissue and organ samples were taken for histology. Liver and whole-body anticoagulant residues were assessed.. No turtles or boas died due to anticoagulant exposure. However, anticoagulant intoxication was suspected in one iguana dosed with brodifacoum. A few treated ameivas died but exhibited no hemorrhaging. Liver residue levels were higher than whole-body remainder residue levels for all species. Unlike the other species, turtles had higher diphacinone residue levels than brodifacoum.. Turtles and boas exhibited a relative insensitivity to diphacinone and brodifacoum, while the lizards appeared to be somewhat more sensitive to these compounds. This study provides data for future assessments of the risks to these species associated with anticoagulant use. Published 2019. This article is a U.S. Government work and is in the public domain in the USA.

Topics: 4-Hydroxycoumarins; Animals; Anticoagulants; Phenindione; Reptiles; Rodenticides

The anticoagulant rodenticides brodifacoum, chlorophacinone, and diphacinone have been proposed for broadcast application in some forested areas in Hawai'i to protect rare and endangered native bird species from introduced mice and rats. Groundwater resources in Hawai'i are prone to contamination due to the intrinsic aquifer vulnerability to leaching from the land surface. Because of the hydrogeologic complexity, Hawai'i uses a Tier-I leaching assessment tool, CLERS, to make registration decisions for new or existing chemicals. The CLERS tool uses soil and pesticide properties as well as water recharge through the soil profile in a GIS framework to estimate mass attenuation of the chemicals at a given depth and compares against this attenuation factor against those of a known leacher and a non-leacher. Disturbed soil samples were collected across the state of Hawai'i, including the islands of Hawai'i, Kaho'olawe, Kaua'i, Lana'i, Maui, Moloka'i, and O'ahu, with two sampling locations per island, except for Kaua'i which had three. As only limited information on chemical properties of these anticoagulants in soils is available, laboratory experiments were performed to determine the sorption capacity (K

Topics: 4-Hydroxycoumarins; Anticoagulants; Environmental Monitoring; Forests; Groundwater; Hawaii; Phenindione; Risk Assessment; Rodenticides; Soil Pollutants

An analytical method based on ultra-high performance liquid chromatography (UHPLC) coupled to Orbitrap high resolution mass spectrometry was developed for the determination of rodenticides (bromadiolone, brodifacoum, difenacoum, chlorophacinone, diphacinone, coumachlor and warfarin) in liver matrix. Different extraction conditions were tested, obtaining the best results when the "dilute and shoot" method (acidified acetonitrile as extraction solvent) and a clean-up step with primary secondary amine (PSA) were used. The optimized method was validated, obtaining recoveries ranging from 60 to 120%. Repeatability and reproducibility were evaluated obtaining values lower than 20%, except for brodifacoum at 10μg/kg. Limits of quantification (LOQs) ranged from 0.1 to 0.5μg/kg, except for brodifacoum, which was 100μg/kg. Six liver samples were analyzed and diphacinone and chlorophacinone were detected in three samples at concentrations ranging from 4μg/kg to 13μg/kg. Moreover a retrospective screening of rodenticide metabolites in those samples and in animal forensic samples was developed based on Orbitrap capabilities. Brodifacoum was detected in three samples, and warfarin alcohol, which is a metabolite of warfarin, was also detected in one sample.

Topics: 4-Hydroxycoumarins; Acetonitriles; Animals; Chromatography, Liquid; Coumarins; Indans; Liver; Mass Spectrometry; Phenindione; Rabbits; Reproducibility of Results; Retrospective Studies; Rodenticides; Warfarin

Five horses originating from 4 different California race tracks were submitted to the California Animal Health and Food Safety Laboratory for necropsy and diagnostic workup. The 5 horses had a history of sudden collapse and death during exercise. In all of them, massive hemoperitoneum and hemorrhages in other cavities or organs were observed. The liver from these 5 animals and from 27 horses that had been euthanized due to catastrophic leg injuries (controls) were subjected to a rodenticide anticoagulant screen. Traces of brodifacoum, diphacinone, or bromadiolone were detected in the 5 horses with massive bleeding (5/5), and no traces of rodenticides were detected in control horses (0/27). Other frequent causes of massive hemorrhages in horses were ruled out in 4 of the cases; one of the horses had a pelvic fracture. Although only traces of anticoagulants were found in the livers of these horses and the role of these substances in the massive bleeding remains uncertain, it is speculated that exercise-related increases in blood pressure may have reduced the threshold for toxicity of these anticoagulants.

Topics: 4-Hydroxycoumarins; Animals; Anticoagulants; California; Hemoperitoneum; Hemorrhage; Horse Diseases; Horses; Liver; Male; Phenindione; Physical Conditioning, Animal; Rodenticides

From 1971 through 1997, we documented 51 cases (55 individual animals) of poisoning of non-target wildlife in New York (plus two cases in adjoining states) (USA) with anticoagulant rodenticides--all but two of these cases occurred in the last 8 yrs. Brodifacoum was implicated in 80% of the incidents. Diphacinone was identified in four cases, bromadiolone in three cases (once in combination with brodifacoum), and chlorophacinone and coumatetralyl were detected once each in the company of brodifacoum. Warfarin accounted for the three cases documented prior to 1989, and one case involving a bald eagle (Haliaeetus leucocephalus) in 1995. Secondary intoxication of raptors, principally great horned owls (Bubo virginianus) and red-tailed hawks (Buteo jamaicensis), comprised one-half of the cases. Gray squirrels (Sciurus carolinensis), raccoons (Procyon lotor) and white-tailed deer (Odocoileus virginianus) were the most frequently poisoned mammals. All of the deer originated from a rather unique situation on a barrier island off southern Long Island (New York). Restrictions on the use of brodifacoum appear warranted.

Topics: 4-Hydroxycoumarins; Animals; Animals, Wild; Anticoagulants; Bird Diseases; Deer; Hemorrhage; Indans; New York; Phenindione; Poisoning; Raccoons; Raptors; Rodenticides; Sciuridae; Warfarin