Field evidence of secondary poisoning of foxes (Vulpes vulpes) and buzzards (Buteo buteo) by bromadiolone, a 4-year survey.

This paper presents the result of a 4 year survey in France (1991-1994) based on the activity of a wildlife disease surveillance network (SAGIR). The purpose of this study was to evaluate the detrimental effects of anticoagulant (Ac) rodenticides in non-target wild animals. Ac poisoning accounted for a very limited number of the identified causes of death (1-3%) in most species. Predators (mainly foxes and buzzards) were potentially exposed to anticoagulant compounds (especially bromadiolone) via contaminated prey in some instances. The liver concentrations of bromadiolone residues were elevated and species-specific diagnostic values were determined. These values were quite similar to those reported in the literature when secondary anticoagulant poisoning was experimentally assessed.

Toxicity and kinetics of amitraz in dogs.

OBJECTIVE: To evaluate the toxic effects of amitraz in dogs and their reversal by various doses of atipamezole. ANIMALS: 6 male 1-year-old Beagles. PROCEDURE: Dogs were given 100 mg of amitraz/kg of body weight, PO. Atipamezole was administered at 3 dose rates. Clinical examination and blood sample collection were performed regularly for 48 hours to examine biological parameters and determine the toxicokinetics of amitraz as well as the efficacy of the antidote. A specific high-performance thin layer chromatographic method was developed to determine plasma amitraz concentrations. RESULTS: Clinical signs of toxicosis included sedation, bradycardia, polyuria, hypothermia, and hyperglycemia, all of which could be related to the alpha 2-agonist activity of amitraz, and were reversed by low doses of atipamezole (50 micrograms/kg, IM), a potent alpha 2-antagonist, within 10 minutes after injection. Peak plasma concentrations were observed after 5 hours, and the elimination half-life was long (about 24 hours). CONCLUSIONS: All clinical and biological effects observed during the course of amitraz poisoning could be attributed to the parent compound itself and were reversed by low doses of atipamezole. The half-life of amitraz was substantially longer than that in other studies because of the high dose administered. CLINICAL RELEVANCE: Atipamezole can be administered i.m. to dogs with severe amitraz poisoning to reverse all the effects observed.

Loperamide poisoning in the dog.

A retrospective study was conducted of 40 loperamide poisoning cases recorded at the Centre National d'Informations Toxicologiques Veterinaires. An apparent breed susceptibility of Collie dogs was observed. Neurologic disturbances (ataxia and prostration) were significant clinical findings. Treatment with naloxone resulted in rapid reversal of signs without sequelae.

Can household pets be used as reliable monitors of lead exposure to humans?

We investigated the validity of dogs and cats as sentinels of environmental lead exposure to humans. This paper reports findings from a study conducted in Granite City, IL, during the summer of 1991. At this site, a former secondary lead smelter had been in activity for more than 80 years. The smelter was shut down in 1982. The surrounding area was found to be contaminated with lead, with soil lead concentrations above 5000 ppm in some places. The Illinois Department of Public Health conducted a survey in the community to determine the effects of lead on the local population. We sampled dogs and cats owned by these people. Our results suggest that living near a closed lead smelter, with heavy soil contamination, was not associated with high blood lead concentrations in pets, or their owners. There was a significant relationship between BLC (blood lead concentrations), in indoor pets and younger children, which was consistent with our hypothesis that pets could be used to monitor childhood lead exposure. We also found that, when there was one pet with a high BLC in a house, the likelihood of finding one person with a BLC above 10 micrograms/dl was significantly increased.

Anticoagulant poisoning in animals: a simple new high-performance thin-layer chromatographic (HPTLC) method for the simultaneous determination of eight anticoagulant rodenticides in liver samples.

The purpose of this study was to develop and evaluate a technique for the analysis of anticoagulant rodenticides in serum and liver samples using a new high-performance thin-layer chromatographic apparatus. Detection limits were estimated at 0.2 micrograms/g in liver extracts for eight different substances. Overall, this technique was repeatable and reproducible. The percent recovery was greater than 87% for each substance. Liver and serum samples of animals known to be exposed to one anticoagulant and showing clinical signs of poisoning were analyzed. Concentrations measured varied between 0.2 and 3 micrograms/g (liver extracts). Only blood samples from one dog could be analyzed. The concentration was 150 ng/mL the first day after admission and 140 ng/mL the following day. Analyses are technically easily and rapidly performed, and they are inexpensive. Therefore, this technique could be a valuable alternative to current high-performance liquid chromatographic methods.

Relationship between soil lead, dust lead, and blood lead concentrations in pets and their owners: evaluation of soil lead threshold values.

This paper reports the results of a study conducted in Granite City, Illinois during the months of August through October 1991. The study involved a subpopulation of 77 households having 106 dogs and cats which was a corollary to a major study conducted in humans by the Illinois Department of Public Health to evaluate lead exposure. A secondary lead smelter had been in operation in this town for almost 80 years and was shut down in 1982. Important soil contamination with lead was reported and this paper presents data regarding levels of soil and dust lead and associated blood lead concentrations in animals and their owners in a total of 77 households. Overall, blood lead concentrations (BLC) were low (0-13 micrograms/dl in the animal owners; 0-28 micrograms/dl in pets). There was no significant relationship between soil or dust lead and BLC in humans; however, the relationship was significant in animals. Odds ratios were computed to determine whether 500 or 1000 ppm lead in environmental samples was associated with increased risk of having a high BLC. We could not find any increased risk in humans, while the risk did increase in animals. It is concluded that animals are more at risk than their owners of having a high BLC when exposed to the same contaminated environment and can be used to monitor the bioavailability of lead.

Low blood lead concentration associated with various biomarkers in household pets.

A former secondary lead smelter was in operation in Granite City, Ill, until the early 1980s. As a result, the surrounding area is heavily contaminated with lead. Soil concentrations as high as 5,000 ppm have been measured in prior studies. Because of growing concerns about health defects associated with low levels of lead exposure in human beings, a major study has been conducted on people living in the area. The study reported here was a corollary to the human exposure study. Lead concentration was determined in 84 dogs and 26 cats in the town and ranged between < 5 and 28 micrograms/dl. None of the dogs had clinical signs of lead poisoning. The CBC and serum biochemical values did not indicate many significant differences between dogs with a high (> or = 10 micrograms/dl) or low blood lead concentration (BLC). Hemoglobin concentrations were lower, and WBC counts were higher in dogs and cats with higher BLC, but they were still within reference ranges. Free erythrocyte protoporphyrin concentration was determined. Normal values appeared to be similar for dogs and cats. Only animals with BLC > or = 20 micrograms/dl were found to have somewhat increased concentration of free erythrocyte protoporphyrin. delta-Aminolevulinic acid dehydratase activity was measured and found to be negatively correlated with BLC. The relation was strong, even at low BLC (5 to 10 micrograms/dl) in both species. Age or sex difference was not observed. Therefore, biological changes associated with low BLC were limited to BLC in the 10- to 30-micrograms/dl range.

Case reports of lead poisoning in dogs from the National Animal Poison Control Center and the Centre National D'Informations Toxicologiques, Veterinaires: anecdotes or reality?

This paper presents case reports of lead toxicoses from 2 major animal poison control centers in Europe and North America, gathered from 1985 through 1989. All results examined here involved cases assessed as "toxicosis" or "suspected toxicosis" by the National Animal Poison Control Center (NAPCC) or the Centre National d'Informations Toxicologiques Veterinaries (CNITV). 537 cases were reported to the NAPCC, most of them concerning dogs (59%). In France, most of the 362 cases involved cattle (57.2%). There was an increased number of cases reported during late summer and early fall, and a decreased number of cases in November and December, in both centers. Dogs intoxicated were predominantly young animals (60% were less than 2 years old). No sex difference was noted. Pure bred dogs appeared more often involved than mixed-breed ones, but the breed distribution closely resembles dog breed distribution in the US. The source of lead was usually unknown and, when information was available, paint seemed to be the most common cause of poisoning. Clinical signs reported to the animal poison control centers involved the CNS and GI tract. Results from the French and the American database showed similar trends. They are compared to data from veterinary clinics and veterinary colleges in the US and Australia. In each case, data are very similar to what was reported to the CNITV and the NAPCC. It is concluded that animal poison control centers databases can provide a useful tool for better knowledge of animal poisoning. They can also help identify unexpected toxicologic problems related to drug administration or pesticide use.