Search

Introduction: Self-poisoning with herbicides is an important reason for hospital admission and death in Asia. Although some herbicides have a well-described toxicity profile in humans, many of the newer compounds rely on extrapolation from animal results as no published literature on clinical outcomes of human self-poisoning has been described. One example of these compounds is bispyribac, a selective herbicide used in rice and wheat cultivation that is marketed in two containers, one containing bispyribac 400 g/L with a solvent and the other the surfactant, polyethylene glycol. We present the first case series of acute human self-poisoning with an herbicide product containing bispyribac., Methods: Clinical data for all patients who presented with acute poisoning from a bispyribac-containing herbicide (Nominee) to two general hospitals in Sri Lanka from June 2002 to January 2009 were collected prospectively. Admission and serial blood samples were collected from consenting patients to confirm exposure and to study the toxicokinetics of bispyribac, respectively., Results: One hundred ten patients with a history of bispyribac ingestion presented after a median time of 4 h post-ingestion. There were three deaths at 15, 6, and 5 h post-ingestion because of asystolic cardiac arrest. All three patients had reduced Glasgow Coma Score (GCS) (3, 12, and 13, respectively) of whom the former two had co-ingested ethanol and developed tonic-clonic seizures. Admission blood sample was obtained from the former two of these patients but bispyribac was detected in only one of these patients. The other patient presented 2.5 h post-ingestion with a GCS of 12 but bispyribac was not detected. Excluding the patient with undetectable bispyribac, a conservative estimate of the case fatality ratio at 1.81% (95% confidence interval 0.32-5.8) can be made. The majority of the remaining patients had self-limiting upper gastrointestinal symptoms and eight patients had an abnormal GCS on presentation to hospital. The overall median hospital stay was 3 days. Bispyribac was not detectable on admission in 21 patients; in the remaining patients, the median plasma concentration was 50.55 microg/mL (interquartile range 1.28-116.5; n=32). The peak concentration was noted around 3 h post-ingestion and plasma bispyribac concentration did not predict the severity of poisoning., Conclusion: The majority of patients developed self-resolving symptoms and were successfully managed in rural general hospitals without transfer to larger tertiary hospitals. Patients who died developed significant poisoning within 6 h and plasma bispyribac concentrations did not appear to predict mortality. The lack of correlation between bispyribac outcomes and the available plasma concentrations may be because of exposure to nonbispyribac components or other undefined factors. Clinical outcomes from acute self-poisoning with bispyribac-containing herbicides appear to be relatively more favorable than other commonly used herbicides.

The present study deals with the genotoxicity assessment of vineyard pesticides in fish exposed in the field or in mesocosm conditions. Primary DNA damage was quantified as strand breaks using the single cell gel electrophoresis assay (Comet assay) applied to fish erythrocytes. In a first experiment, a significant genotoxic effect was observed following an upstream-downstream gradient in early life stages of brown trout (Salmo trutta fario) exposed in the Morcille River contaminated by a mixture of vineyard pesticides during three consecutive years. The pronounced response in terms of DNA damage reported in the present study could argue for a high sensitivity of fish early life stage and/or a high level of exposure to genotoxic compounds in the Morcille River. This stresses the interest in using trout larvae incubated in sediment bed to assess genotoxic compounds in the field. In a second experiment, adult European topminnow (Phoxinus phoxinus) were exposed in water running through artificial channels to a mixture of diuron and azoxystrobin, two of the main pesticides detected in the Morcille watershed. As compared with the unexposed channel, a 3-5-fold increase in the DNA damage was observed in fish exposed to chronic environmental pesticide concentrations (1-2 microg L(-1) for diuron and 0.5-1 microg L(-1) for axoxystrobin). A single 6h pulse of pesticide (14 microg L(-1) of diuron and 7 microg L(-1) of azoxystrobin) was applied to simulate transiently elevated chemical concentrations in the river following storm conditions. It did not increase genotoxicity. After a 1-month recovery period, DNA damage in exposed fish erythrocytes recovered to unexposed level, suggesting possible involvement of both repair mechanisms and cellular turnover in this transient response. This work highlights that vineyard treatment by pesticides and in particular diuron and azoxystrobin can represent a genotoxic threat to fish from contaminated watershed rivers.

The development of discolored urine may have many possible causes. Here we present the case of a 76-year-old woman who was admitted after ingesting the inorganic herbicides, mefenacet and imazosulfuron. Her urine color changed to green almost immediately. Since the patient had no specific medication or medical history we considered that the most likely cause of the change in urine color was the ingestion of the herbicides. Spectrophotometric analysis of the urine was conducted and a peak was observed in the green area of the wavelength spectrum. These findings show that mefenacet and imazosulfuron should be considered in the differential diagnosis of green discolored urine.

REBIN GT SC (glyphosate isopropylamine and butafenacil, hereinafter referred to as "REBIN") is a nonselective herbicide which was developed by Syngenta Japan K. K. and was registered in July 2001 as a herbicide. We report the first case of acute poisoning by REBIN. In this case (Age 67, male), high fever and general fatigue developed immediately after REBIN inhalation. Furthermore, urine sugar, urine protein, high LDH and high GPT were observed. But the patient showed a tendency of recovery after the lapse of 48 hours by the intravenous fluid replacement, hydrocortisone sodium succinate (Solu-Cortef), glycyrrhizin (Stronger Neo-Minophagen C) and glutathione (Tathion). He recovered satisfactorily. It is necessary to respect the instructions for the use of REBIN. In addition, in order to prevent inhalation of REBIN, the proper use of instruments and spray at about 30 cm under knee are essential.