-
Archives of Toxicology Oct 1975In three cases of intoxication by Gramoxone¿, the concentration of paraquat dichloride in blood, dialysate, feces, and urine was determined spectrophotometrically after...
In three cases of intoxication by Gramoxone¿, the concentration of paraquat dichloride in blood, dialysate, feces, and urine was determined spectrophotometrically after a clean-up of the biological material by means of ion exchange chromatography (with Dowex 50W-X12 or Zeo-Karb 225). Although good results were obtained after clean-up with Dowex 50W-X12, Zeo-Karb was preferred as ion exchange resin, especially when large sample volumes were needed for the determination. The reported findings indicate that: only 5 to 10% of an ingested dose of paraquat dichloride is absorbed in man, Fullers' earth is very useful, and that primary, e.g. immediate, hemodialysis is necessary.
Topics: Adult; Aluminum Silicates; Feces; Female; Humans; Ion Exchange Resins; Male; Middle Aged; Paraquat; Poisoning; Renal Dialysis
PubMed: 1242886
DOI: 10.1007/BF00353313 -
British Medical Journal Jan 1976
Topics: Humans; Paraquat
PubMed: 1247727
DOI: 10.1136/bmj.1.6000.42 -
Journal of Agricultural and Food... Jun 2002During the many years of paraquat usage, wide ranges of investigations of its environmental impact have been conducted. Much of this information has been published, but... (Review)
Review
During the many years of paraquat usage, wide ranges of investigations of its environmental impact have been conducted. Much of this information has been published, but key, long-term field studies have not previously been presented and assessed. The purpose of this review is to bring together and appraise this information. Due to the nature of paraquat residues in soils, the major part (some 99.99%) of a paraquat application that reaches the soil within the typical Good Agricultural Practice (GAP) is strongly adsorbed to soils of a wide variety of textures. This is in equilibrium with an extremely low concentration in soil solution. However, the paraquat in soil solution is intrinsically biodegradable, being rapidly and completely mineralized by soil microorganisms. The deactivation of the biological activity of paraquat in soils, due to sorption, has been investigated thoroughly and systematically. It is recognized that the determination of total soil residues by severe extraction procedures provides no insight into the amount of paraquat biologically available in soil. Consequently, the key assay developed for this purpose, namely, the strong adsorption capacity-wheat bioassay (SAC-WB) method, has proved to be valuable for determination of the adsorption capacity relevant to paraquat for any particular soil. This method has been validated in the field with a series of long-term (>10 years) trials in different regions of the world. These trials have also shown that, following repeated applications of very high levels of paraquat in the field, residues not only reach a plateau but also subsequently decline. This demonstrates that the known biodegradation of paraquat in soil pore water plays an important role in field dissipation. The biological effects of paraquat in the field have been assessed under unrealistically high treatment regimes. These trials have demonstrated that the continued use of paraquat under GAP conditions will have no detrimental effects on either crops or soil-dwelling flora and fauna. Any such effects can occur only under extreme use conditions (above the SAC-WB), which do not arise in normal agricultural practice.
Topics: Adsorption; Australia; Biodegradation, Environmental; Herbicides; Netherlands; Paraquat; Pesticide Residues; Soil; United Kingdom; United States
PubMed: 12059135
DOI: 10.1021/jf011323x -
Human & Experimental Toxicology Jan 19901. The toxicokinetics of paraquat were studied in 18 cases of acute human poisoning using a specific radioimmunoassay. Plasma paraquat concentration exhibited a mean...
1. The toxicokinetics of paraquat were studied in 18 cases of acute human poisoning using a specific radioimmunoassay. Plasma paraquat concentration exhibited a mean distribution half-life (t1/2 alpha) of 5 h and a mean elimination half-life (t1/2 beta) of 84 h. Cardiovascular collapse supervened early during the course of the intoxication and was associated with the distribution phase. Death related to pulmonary fibrosis occurred late and was associated with the elimination phase. 2. Pharmacokinetic analysis of urine paraquat excretion confirmed the biphasic decline of paraquat. Moreover, renal paraquat and creatinine clearances were not correlated but renal paraquat clearance was never higher than the renal creatinine clearance. 3. Tissue paraquat distribution was ubiquitous with an apparent volume of distribution ranging from 1.2 to 1.6 l/kg. Muscle could represent an important reservoir explaining the long persistence of paraquat in plasma and urine for several weeks or months after poisoning.
Topics: Adult; Aged; Female; Humans; Infant; Male; Paraquat; Renal Dialysis; Time Factors; Tissue Distribution
PubMed: 2328151
DOI: 10.1177/096032719000900103 -
Veterinary and Human Toxicology Aug 1994Two cases of paraquat poisoning resulting from skin absorption are reported. One patient died from respiratory failure 26 d after deliberate application of the herbicide... (Review)
Review
Two cases of paraquat poisoning resulting from skin absorption are reported. One patient died from respiratory failure 26 d after deliberate application of the herbicide onto his whole body as a treatment for scabies. The other patient developed extensive dermatitis (probably a complication of pre-existing psoriasis). Only a moderate and transitory impairment of this latter patient's renal and respiratory functions were observed after repeated exposure of his damaged skin to a dilute paraquat spray.
Topics: Adult; Humans; Male; Middle Aged; Occupational Exposure; Paraquat; Skin Absorption
PubMed: 7975137
DOI: No ID Found -
Mikrochimica Acta Jun 2022A sensitive nanopipette sensor is established through a unique design of host-guest recognition, which could be further enhanced by the introduction of gold...
A sensitive nanopipette sensor is established through a unique design of host-guest recognition, which could be further enhanced by the introduction of gold nanoparticles (Au NPs). Generally, the nanopipette is conjugated with caboxylatopillar[5]arenes (CP[5]) or carboxylated leaning pillar[6]arene (CLP[6]) to generate recognition sites. After the addition of pesticide molecules, they would be captured by CP[5] (or CLP[6]), resulting in a significant electronegativity change on the nanopipette's inner surface, which could be determined by the ionic current change. The CP[5]-modified nanopipette exhibited reliable selectivity for paraquat, while the CLP[6]-modified nanopipette showed an ability of detection for both paraquat and diquat. The addition of Au NPs improved the selectivity and sensitivity of the CP[5]-Au NP-modified nanopipette for paraquat sensing. After optimization by lowering the size of the Au NPs, CP[5]-Au NPs (3 nm)-modified nanopipettes achieved lower detection limits of 0.034 nM for paraquat. Furthermore, in real sample analysis, this sensor demonstrates exceptional sensitivity and selectivity. This study provides a new strategy to develop nanopipette sensors for practical small molecule detection. The gold nanoparticles enhanced quartz nanopipette sensor based on host-guest interaction was firstly established, which could achieve an excellent limit of detection of 3.4 × 10 mol/L for paraquat.
Topics: Electrochemical Techniques; Gold; Metal Nanoparticles; Paraquat
PubMed: 35680710
DOI: 10.1007/s00604-022-05348-9 -
American Journal of Public Health Jul 1983In March 1978, 13 (21 per cent) of 61 marijuana samples from the southwestern United States were found to be contaminated with the herbicide paraquat, a pulmonary toxin,...
In March 1978, 13 (21 per cent) of 61 marijuana samples from the southwestern United States were found to be contaminated with the herbicide paraquat, a pulmonary toxin, in concentrations from 3 to 2,264 parts per million. The source of the contamination was an aerial spraying program in Mexico, supported indirectly by United States funds. To evaluate US exposure, a nationwide survey of the paraquat content of confiscated marijuana was conducted. The survey found 33 (3.6 per cent) of 910 marijuana specimens to contain detectable paraquat. In states adjacent to Mexico (Census Region VI), 23 (12.8 per cent) of 180 specimens were contaminated. Combustion testing indicated that approximately 0.2 per cent of paraquat on marijuana passes into smoke. From these data, we projected that 100-200 marijuana smokers in Census Region VI would be exposed by inhalation to 500 micrograms or more of paraquat per year, a dose judged to represent a health hazard; nationally, between 150 and 300 smokers were projected to have such exposure. Another 6,000 persons in Region VI and 9,000 nationally were projected to be at risk of exposure to between 100 and 499 micrograms of paraquat annually. The risk of paraquat exposure was greatest among those smokers who make one large purchase of marijuana per year. No clinical cases of paraquat poisoning were recognized among marijuana smokers during these studies, but no systematic national search for such cases was undertaken.
Topics: Cannabis; Epidemiologic Methods; Humans; Mexico; Paraquat; Risk; Smoke; United States
PubMed: 6859364
DOI: 10.2105/ajph.73.7.784 -
PLoS Medicine Feb 2008The author discusses whether the new paraquat formulation introduced in Sri Lanka is a step forward in reducing deaths from paraquat self-poisoning. (Review)
Review
The author discusses whether the new paraquat formulation introduced in Sri Lanka is a step forward in reducing deaths from paraquat self-poisoning.
Topics: Chemistry, Pharmaceutical; Humans; Paraquat; Suicide, Attempted
PubMed: 18303945
DOI: 10.1371/journal.pmed.0050058 -
Medical Toxicology and Adverse Drug... 1988In this review the efficacy of haemoperfusion in the treatment of paraquat poisoning is addressed. 42 reports containing sufficient information of paraquat-poisoned... (Review)
Review
In this review the efficacy of haemoperfusion in the treatment of paraquat poisoning is addressed. 42 reports containing sufficient information of paraquat-poisoned patients were evaluated. These reports, from 35 patients reported in the literature and 7 new cases, were chosen for the following reasons: the timed plasma paraquat concentrations were known, patient outcome was known, and details of haemoperfusion were available. In some cases, haemodialysis was also performed. The plasma paraquat concentrations and the specific times post-ingestion were plotted on a contour graph that predicts the probability of survival. Comparison of the predicted probability of survival versus the actual outcome showed that haemoperfusion, single or repeated, did not affect patient survival. None of the patients whose initial plasma concentrations were greater than 3 mg/L paraquat survived, regardless of the time after ingestion that the concentrations were measured, and despite haemoperfusion. Therefore, such patients might not be considered for haemoperfusion because of their uniformly bad prognosis, despite the procedure being used, and because of the morbidity, discomfort and cost associated with it. Clearly, the need for better techniques to remove paraquat and to prevent the consequences of the metabolic effects of the compound are required urgently before the treatment of the paraquat-poisoned patient will be successful.
Topics: Adolescent; Adult; Child; Child, Preschool; Female; Hemoperfusion; Humans; Male; Middle Aged; Paraquat; Renal Dialysis
PubMed: 3285127
DOI: 10.1007/BF03259932 -
Molecular Plant Jan 2024
Topics: Herbicides; Paraquat
PubMed: 38053336
DOI: 10.1016/j.molp.2023.12.001