Rodenticides exposures

Uses. High explosive rodenticide Exposure. Inhalation... 

One study conducted in Britain between 1983 and 1989 was of barn owls found dead in the field 10% of the sample of 145 birds contained anticoagulant rodenticide residues in their livers, and difenacoum and brodifacoum were prominent among them (Newton et al. 1990). In another study, barn owls were fed rats that had been dosed with flocoumafen. It was found that a substantial proportion of the rodenticide ingested by owls was eliminated in pellets (Eadsforth et al. 1991). The authors suggest that exposure of owls to rodenticides in the field may be monitored by analysis of pellets dropped at roosts or regular perching places. 

Because of the delay in the appearance of hemorrhaging following exposure to warfarin and related ARs, a suitable interval must elapse between exposure of experimental animals to the chemical and the assessment of mortality in toxicity testing. Typically, this period is at least 5 days. Some values of acute oral LD50 of rodenticides to vertebrates are given in Table 11.2. 

As discussed earlier, a problem with these field incidents is that the low levels of rodenticides found in many of the poisoned birds are of similar magnitude to those in birds surviving exposure. A low residue level may signify everything or nothing. Additional evidence is needed to establish that the concentrations of rodenticide present in the livers of birds or mammals found in the field are sufficient to have caused death, for example, the presence of hemorrhaging in the carcasses. 

Shore, R.E., Birks, J.D.S., and Ereestone, R (1999). Exposure of non-target vertebrates to second generation rodenticides with particular reference to the polecat. New Zealand Journal of Ecology 23, 199-206. 

Analytical chemistry is a critical component of worker safety, re-entry, and other related studies intended to assess the risk to humans during and subsequent to pesticide applications. The analytical aspect takes on added significance when such studies are intended for submission to the U.S. Environmental Protection Agency and/or other regulatory authorities and are thus required to be conducted according to the Federal Insecticide, Fungicide and Rodenticide Act (FIFRA) Good Laboratory Practice (GLP) Standards, or their equivalent. This presentation will address test, control, and reference substance characterization, use-dilution (tank mix) verification, and specimen (exposure matrix sample) analyses from the perspective of GLP Standards requirements. 

Pesticides are used to kill household insets, rats, cockroaches, and other pests. Pesticides can be classified based on their chemical nature or use as organophosphates, carbonates, chlorinated hydrocarbons, bipyridyls, coumarins and indandiones, rodenticides, fungicides, herbicides, fumigants, and miscellaneous insecticides. The common adverse effects are irritation of the skin, eyes, and upper respiratory tract. Prolonged exposure to some chemicals may cause damage to the central nervous system and kidneys [32,33]. 

However, a hner level of detail may be reqnired in some sitnations. For example, predatory birds feeding on rodents in an area partly treated with rodenticides may enconnter a bimodal distribntion of residnes in their prey, snch that most prey contain no residnes bnt others contain a lethal dose for the predator. If the unit of analysis were dehned as a whole day s foraging, with residues being averaged over all available prey items, the model might indicate that all the predators experience a snblethal exposnre. In reality, most predators would experience zero exposure, but those that ate a contaminated prey item would die a significantly different result. Therefore, the unit of analysis in this case should be individual foraging events for individual predators. 

Warfarin. Warfarin is a popular rodenticide particularly common in rat poison preparations. Because of its toxic nature, assessment of workplace and environmental exposures is of concern. Warfarin can be quickly and easily determined by reverse phase HPLC. Details of the procedure applied in our laboratory are as follows ... 

R. L. Jones and G. Mangels, "Review Of The Validatim Of Models Used In Federal Insecticide, Fungicide, and Rodenticide Act Environmental Exposure Assessments , Env. Tox. Chem. 2002,21 (8), 1535-1544. 

TABLE 15.3. Number of exposures to long-acting anticoagulant rodenticides and deaths reported by the American Association of Poison Control Centers - Toxic Exposure... 

Fluoride toxicosis reported primarily in animals can be acute or chronic. Acute toxicosis is by exposure to insecti-cides/rodenticides and volcanic dust. Fluoride is metabolized via renal excretion and is preferentially deposited in... 

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