Excretion of insecticides

Chlordecone: development of a physiologically based pharmacokinetic tool to support human health risks assessments

Chlordecone (CD; Kepone™) is a carcinogenic organochlorine insecticide with neurological, reproductive, and developmental toxicity that was widely used in the French West Indies (FWI) from 1973 to 1993 to fight banana weevils. Although CD has not been used there for more than 25 years, it still persists in the environment and has polluted the waterways and soil of current and older banana fields. Today, human exposure to CD in the FWI mainly arises from consuming contaminated foodstuffs. The aims of this study were to develop a physiologically based pharmacokinetic (PBPK) model in the rat and extrapolate it to humans based on available pharmacokinetic data in the literature. A comparison of simulations using the rat model with published experimental datasets showed reasonable predictability for single and repetitive doses, and, thus, it was extrapolated to humans. The human PBPK model, which has seven compartments, is able to simulate the blood concentrations of CD in human populations and estimate the corresponding external dose using the reverse dosimetry approach. The human PBPK model will make it possible to improve quantitative health risk assessments for CD contamination and reassess the current chronic toxicological reference values to protect the FWI population.

Successful organ transplantation from donors poisoned with a carbamate insecticide

Currently, liver transplantation is the only option for patients with end-stage liver disease. In Brazil, the mortality rate on the waiting list is about 25%. Multiple strategies to expand the donor pool are being pursed, however, grafts from poisoned donors are rarely used. This report documents successful liver, kidney and heart transplantations from four female donors who suffered brain death by hypoxia despite cardiopulmonary resuscitation following Aldicarb exposure ([2-methyl-2-(methylthio)propionaldehyde O-(methylcarbamoyl)-oxime]). The success rate of 12 grafts from four donors poisoned by Aldicarb was 91% 6 months after transplantation. Poisoned patients are another pool of organ donors who at present are probably underused by transplantation services. More studies are necessary to confirm the safety for the recipients.

Organ procurement and successful transplantation after malathion poisoning

BACKGROUND

One of the major limitations to organ procurement and donation is the lack of suitable donors. As the demand for suitable organs exceeds the supply, identification of potential donors continues to evolve. Due to perceived risks of transmittable toxins and insufficient understanding of toxicological fate, poisoned patients are often overlooked as organ donors.

CASE REPORT

A 17-year-old white male was found by his mother having a seizure in bed. A strong odor of pesticides was noted and an empty container of malathion was found. He was transported to an outlying hospital and underwent prolonged cardiopulmonary resuscitation. The patient exhibited symptoms consistent with cholinergic poisoning and received a total of 12 mg of atropine and a pralidoxime bolus of 1 g followed by an infusion at 500 mg/h. Initial plasma cholinesterase was 1433 IU/L (normal 7500-14,600). The patient developed aspiration pneumonia and remained comatose. No further treatment for cholinergic toxicity was needed 5 days after admission and a cerebral blood flow scan confirmed brain death. After review of the available literature on the disposition andfate of malathion in human tissues, the patient's liver and kidneys were harvested for transplantation. The recipients were all doing well 1 year posttransplantation.

CONCLUSIONS

This case of successful transplantation after organophosphate exposure underscores the fact that poisoned patients should not be overlooked as transplant candidates. Decisions should be based on the clinical presentation and knowledge of the properties of the toxin.

Rise and fall of endrin usage in Washington State fruit orchards: effects on wildlife

A study of the effects of endrin on wildlife was conducted from 1981 to 1983 in fruit orchards in central Washington State. The single post-harvest application of endrin as a rodenticide resulted in both acute and chronic toxicity to a variety of avian species. Of 194 birds found dead, brains of 125 were analysed; endrin toxicosis accounted for > 24% of the total and 37% of those analysed. Most mortality occurred soon after application, but several raptors died during the spring and summer. Most wildlife sampled in the orchard system contained residues of endrin. There was no evidence that endrin depressed reproductive success. Use of endrin abruptly declined during this study and its use is currently limited to emergency situations. Wildlife mortality from endrin also decreased; only six endrin-related mortalities were detected the last year of the study and there have been no reports of die-offs since the study ended.