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Elser BA, Hing B, Stevens HE. A narrative review of converging evidence addressing developmental toxicity of pyrethroid insecticides. Crit Rev Toxicol 2022; 52:371-388. [PMID: 36345971 PMCID: PMC9930199 DOI: 10.1080/10408444.2022.2122769] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Revised: 09/01/2022] [Accepted: 09/05/2022] [Indexed: 11/11/2022]
Abstract
Pyrethroid insecticides are broadly used in agriculture and household products throughout the world. Exposure to this class of insecticides is widespread, and while generally believed to be safe for use, there is increasing concern regarding their effects on neurodevelopment. Due to the critical roles that molecular targets of pyrethroids play in the regulation of neurodevelopment, particular focus has been placed on evaluating the effects of in utero and childhood pyrethroid exposure on child cognition and behavior. As such, this narrative review synthesizes an assessment of converging study types; we review reports of neonatal pyrethroid levels together with current epidemiological literature that convergently address the risk for developmental toxicity linked to exposure to pyrethroid insecticides. We first address studies that assess the degree of direct fetal exposure to pyrethroids in utero through measurements in cord blood, meconium, and amniotic fluid. We then focus on the links between prenatal exposure to these insecticides and child neurodevelopment, fetal growth, and other adverse birth outcomes. Furthermore, we assess the effects of postnatal exposure on child neurodevelopment through a review of the data on pediatric exposures and child cognitive and behavioral outcomes. Study quality was evaluated individually, and the weight of evidence was assessed broadly to characterize these effects. Overall, while definitive conclusions cannot be reached from the currently available literature, the available data suggest that the potential links between pyrethroid exposure and child neurodevelopmental effects deserve further investigation.
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Affiliation(s)
- Benjamin A Elser
- Interdisciplinary Graduate Program in Human Toxicology, Graduate College, The University of Iowa, Iowa City, IA, USA
- Department of Psychiatry, Carver College of Medicine, The University of Iowa, Iowa City, IA, USA
| | - Benjamin Hing
- Department of Psychiatry, Carver College of Medicine, The University of Iowa, Iowa City, IA, USA
- Department of Molecular Physiology and Biophysics, Carver College of Medicine, The University of Iowa, Iowa City, IA, USA
| | - Hanna E Stevens
- Interdisciplinary Graduate Program in Human Toxicology, Graduate College, The University of Iowa, Iowa City, IA, USA
- Department of Psychiatry, Carver College of Medicine, The University of Iowa, Iowa City, IA, USA
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2
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Quindroit P, Beaudouin R, Brochot C. Estimating the cumulative human exposures to pyrethroids by combined multi-route PBPK models: Application to the French population. Toxicol Lett 2019; 312:125-138. [PMID: 31077771 DOI: 10.1016/j.toxlet.2019.05.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Revised: 04/26/2019] [Accepted: 05/07/2019] [Indexed: 01/16/2023]
Abstract
Human biomarkers of exposure to pyrethroid insecticides are usually urinary concentrations of metabolites that can be specific to a pyrethroid or common to several compounds. We developed a global toxicokinetic model that links the external exposure to four widely-used pyrethroids and their isomers (deltamethrin and cis and trans isomers of permethrin, cypermethrin, and cyfluthrin) to the urinary concentrations of metabolites (cis- and trans-DCCA, 3-PBA, F-PBA and DBCA). This global model includes physiologically based pharmacokinetic models for each parent compound and one-compartment models for the metabolites. Existing in vivo, in vitro and in silico data were used for model calibration, and human toxicokinetic data for model evaluation. Overall, the global model reproduced the data accurately as about 90% of predictions were inside the 3-fold error interval. A sensitivity analysis showed that the most influent parameter for each urinary metabolite concentration was the fraction of parent compound that is transformed into that metabolite. The global model was then tested with realistic exposures for the French population: the predictions were consistent with biomonitoring data. The global model is a tool that will improve the interpretation of biomonitoring data for pyrethroids.
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Affiliation(s)
- Paul Quindroit
- Institut National de l'Environnement Industriel et des Risques (INERIS), Unité Modèles pour l'Ecotoxicologie et la Toxicologie (METO), Parc ALATA BP2, 60550, Verneuil en Halatte, France
| | - Rémy Beaudouin
- Institut National de l'Environnement Industriel et des Risques (INERIS), Unité Modèles pour l'Ecotoxicologie et la Toxicologie (METO), Parc ALATA BP2, 60550, Verneuil en Halatte, France
| | - Céline Brochot
- Institut National de l'Environnement Industriel et des Risques (INERIS), Unité Modèles pour l'Ecotoxicologie et la Toxicologie (METO), Parc ALATA BP2, 60550, Verneuil en Halatte, France.
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3
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Yang JS, Qi W, Farias-Pereira R, Choi S, Clark JM, Kim D, Park Y. Permethrin and ivermectin modulate lipid metabolism in steatosis-induced HepG2 hepatocyte. Food Chem Toxicol 2019; 125:595-604. [PMID: 30738135 DOI: 10.1016/j.fct.2019.02.005] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Revised: 01/09/2019] [Accepted: 02/04/2019] [Indexed: 02/06/2023]
Abstract
Recent studies have reported the positive association between exposure to insecticides and increased risk of obesity and type 2 diabetes, which are closely associated with non-alcoholic fatty liver disease (NAFLD). However, it is not known if insecticide exposure can contribute to NAFLD. Thus, the goal of the current study was to determine if insecticide exposures can exacerbate the physiological conditions of NAFLD by modulating hepatic lipid metabolism. The effects of 12 insecticides on triglycerides (TG) accumulation were tested using palmitic acid (PA)-induced HepG2 hepatoma steatosis model. Results showed that among tested insecticides, permethrin and ivermectin significant interacted with palmitic acid to potentiate (permethrin) or decrease (ivermectin) TG accumulation. Further study showed that permethrin significantly promoted fatty acid synthesis, while suppressed lipid oxidation-related genes only under steatosis conditions. In comparison, ivermectin inhibited lipogenesis-related genes and promoted farnesoid X receptor, which upregulates fatty acid oxidation. Results in this study suggested that hepatic lipid metabolism may be more susceptible to insecticide exposure in the presence of excessive fatty acids, which can be associated with the development of NAFLD.
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Affiliation(s)
- Jason S Yang
- Department of Food Science, University of Massachusetts, Amherst, USA
| | - Weipeng Qi
- Department of Food Science, University of Massachusetts, Amherst, USA
| | | | - Stephanie Choi
- Department of Biochemistry and Molecular Biology, University of Massachusetts, Amherst, USA
| | - John M Clark
- Department of Veterinary and Animal Sciences, University of Massachusetts, Amherst, USA
| | - Daeyoung Kim
- Department of Mathematics and Statistics, University of Massachusetts, Amherst, USA
| | - Yeonhwa Park
- Department of Food Science, University of Massachusetts, Amherst, USA.
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Yang JS, Symington S, Clark JM, Park Y. Permethrin, a pyrethroid insecticide, regulates ERK1/2 activation through membrane depolarization-mediated pathway in HepG2 hepatocytes. Food Chem Toxicol 2018; 121:387-395. [PMID: 30205134 PMCID: PMC6235143 DOI: 10.1016/j.fct.2018.09.009] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2018] [Revised: 08/16/2018] [Accepted: 09/06/2018] [Indexed: 12/29/2022]
Abstract
Permethrin is a pyrethroid insecticide that acts thru membrane depolarization and is known to disrupt calcium levels in neurons. Disrupted calcium homeostasis is linked to oxidative stress as well as many other cellular mis-functions and permethrin has been reported to disrupt lipid and glucose metabolism in animals and mammalian cell models. It is not known, however, if permethrin influences calcium levels and its associated cellular mechanisms in liver cells. Thus, the goal of the current study was to investigate the mechanisms of permethrin on calcium-mediated cellular signaling pathway, particularly on activation of extracellular signal-related kinase (ERK1/2 or p42/p44) using human hepatocytes, HepG2. The current results showed that permethrin treatment induced oxidative stress and phosphorylation of ERK1/2, which were dependent upon voltage-sensitive sodium channels (VSSC). It was further determined that permethrin-induced ERK1/2 activation was mediated by the metabotropic glutamate receptors (mGluRs)-phosphoinositide phospholipase C (PLC)-protein kinase C (PKC) pathway, but not by changes of intracellular calcium or ER stress-mediated mechanisms.
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Affiliation(s)
- Jason S Yang
- Department of Food Science, University of Massachusetts, Amherst, MA, USA
| | - Steven Symington
- Department of Biology and Biomedical Sciences, Salve Regina University, Newport, RI, USA
| | - John M Clark
- Department of Veterinary and Animal Sciences, University of Massachusetts, Amherst, MA, USA
| | - Yeonhwa Park
- Department of Food Science, University of Massachusetts, Amherst, MA, USA.
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The pyrethroid insecticides permethrin and esfenvalerate do not disrupt testicular steroidogenesis in the rat fetus. Toxicology 2018; 410:116-124. [PMID: 30243954 DOI: 10.1016/j.tox.2018.09.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2018] [Revised: 08/07/2018] [Accepted: 09/17/2018] [Indexed: 12/17/2022]
Abstract
The present study investigated the effects of maternal exposure to the widely used pyrethroid insecticides, permethrin and esfenvalerate, on fetal testicular steroidogenesis. Pregnant Sprague-Dawley rats were administered permethrin at doses of 1, 10, 50, or 100 mg/kg/day, or esfenvalerate at 0.1, 1, 7.5 or 15 mg/kg/day, by gavage, from gestation day (GD) 13 to 19. Testicular testosterone production and the expression of several key genes necessary for cholesterol and androgen synthesis and transport were assessed in GD 19 male fetuses. Dams treated with 100 mg/kg/day of permethrin or 15 mg/kg/day of esfenvalerate showed clinical signs of neurotoxicity. The highest dose of esfenvalerate also resulted in reduced maternal body weight gain throughout the treatment period. In the fetal testes, mRNA expressions of HMG-CoA synthase and reductase, SR-B1, StAR, P450scc, 3βHSD, P450 17A1, and 17βHSD were not affected by exposure to either pyrethroid. No significant change was observed in ex vivo testosterone production. In conclusion, in utero exposure to permethrin or esfenvalerate has no effect on the testosterone biosynthesis pathway in the fetal rat testis up to maternal toxic doses.
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Choi CY, Cho N, Park SY, Park S, Gil HW, Hong SY. Urine Methyl Hippuric Acid Levels in Acute Pesticide Poisoning: Estimation of Ingested Xylene Volume and Association with Clinical Outcome Parameters. J Korean Med Sci 2017; 32:2051-2057. [PMID: 29115090 PMCID: PMC5680507 DOI: 10.3346/jkms.2017.32.12.2051] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/01/2017] [Accepted: 08/20/2017] [Indexed: 12/24/2022] Open
Abstract
To determine the relationship between the oral ingestion volume of xylene and methyl hippuric acid (MHA) in urine, we measured MHA in 11 patients whose ingested xylene volume was identified. The best-fit equation between urine MHA and ingested amount of xylene was as follows: y (ingested amount of xylene, mL/kg) = -0.052x² + 0.756x (x = MHA in urine in g/g creatinine). From this equation, we estimated the ingested xylene volume in 194 patients who had ingested pesticide of which the formulation was not available. Our results demonstrated that oxadiazole, dinitroaniline, chloroacetamide, organophosphate, and pyrethroid were xylene-containing pesticide classes, while the paraquat, glyphosate, glufosinate, synthetic auxin, fungicide, neonicotinoid, and carbamate classes were xylene-free pesticides. Sub-group univariate analysis showed a significant association between MHA levels in urine and ventilator necessity in the pyrethroid group. However, this association was not observed in the organophosphate group. Our results suggest that MHA in urine is a surrogate marker for xylene ingestion, and high urine MHA levels may be a risk factor for poor clinical outcome with some pesticide poisoning.
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Affiliation(s)
- Chi Young Choi
- Department of Internal Medicine, Soonchunhyang University Cheonan Hospital, Cheonan, Korea
| | - NamJun Cho
- Department of Internal Medicine, Soonchunhyang University Cheonan Hospital, Cheonan, Korea
| | - Su Yeon Park
- Department of Biostatistics, Soonchunhyang University, College of Medicine, Seoul, Korea
| | - Samel Park
- Department of Internal Medicine, Soonchunhyang University Cheonan Hospital, Cheonan, Korea
| | - Hyo Wook Gil
- Department of Internal Medicine, Soonchunhyang University Cheonan Hospital, Cheonan, Korea
| | - Sae Yong Hong
- Department of Internal Medicine, Soonchunhyang University Cheonan Hospital, Cheonan, Korea.
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Chedik L, Bruyere A, Le Vee M, Stieger B, Denizot C, Parmentier Y, Potin S, Fardel O. Inhibition of Human Drug Transporter Activities by the Pyrethroid Pesticides Allethrin and Tetramethrin. PLoS One 2017; 12:e0169480. [PMID: 28099443 PMCID: PMC5242521 DOI: 10.1371/journal.pone.0169480] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2016] [Accepted: 12/16/2016] [Indexed: 12/11/2022] Open
Abstract
Pyrethroids are widely-used chemical insecticides, to which humans are commonly exposed, and known to alter functional expression of drug metabolizing enzymes. Limited data have additionally suggested that drug transporters, that constitute key-actors of the drug detoxification system, may also be targeted by pyrethroids. The present study was therefore designed to analyze the potential regulatory effects of these pesticides towards activities of main ATP-binding cassette (ABC) and solute carrier (SLC) drug transporters, using transporter-overexpressing cells. The pyrethroids allethrin and tetramethrin were found to inhibit various ABC and SLC drug transporters, including multidrug resistance-associated protein (MRP) 2, breast cancer resistance protein (BCRP), organic anion transporter polypeptide (OATP) 1B1, organic anion transporter (OAT) 3, multidrug and toxin extrusion transporter (MATE) 1, organic cation transporter (OCT) 1 and OCT2, with IC50 values however ranging from 2.6 μM (OCT1 inhibition by allethrin) to 77.6 μM (OAT3 inhibition by tetramethrin) and thus much higher than pyrethroid concentrations (in the nM range) reached in environmentally pyrethroid-exposed humans. By contrast, allethrin and tetramethrin cis-stimulated OATP2B1 activity and failed to alter activities of OATP1B3, OAT1 and MATE2-K, whereas P-glycoprotein activity was additionally moderately inhibited. Twelve other pyrethoids used at 100 μM did not block activities of the various investigated transporters, or only moderately inhibited some of them (inhibition by less than 50%). In silico analysis of structure-activity relationships next revealed that molecular parameters, including molecular weight and lipophilicity, are associated with transporter inhibition by allethrin/tetramethrin and successfully predicted transporter inhibition by the pyrethroids imiprothrin and prallethrin. Taken together, these data fully demonstrated that two pyrethoids, i.e., allethrin and tetramethrin, can act as regulators of the activity of various ABC and SLC drug transporters, but only when used at high and non-relevant concentrations, making unlikely any contribution of these transporter activity alterations to pyrethroid toxicity in environmentally exposed humans.
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Affiliation(s)
- Lisa Chedik
- Institut de Recherches en Santé, Environnement et Travail (IRSET), UMR INSERM U1085, Faculté de Pharmacie, 2 Avenue du Pr Léon Bernard, Rennes, France
- Pôle Pharmacie, Centre Hospitalier Universitaire, 2 rue Henri Le Guilloux, Rennes, France
| | - Arnaud Bruyere
- Institut de Recherches en Santé, Environnement et Travail (IRSET), UMR INSERM U1085, Faculté de Pharmacie, 2 Avenue du Pr Léon Bernard, Rennes, France
| | - Marc Le Vee
- Institut de Recherches en Santé, Environnement et Travail (IRSET), UMR INSERM U1085, Faculté de Pharmacie, 2 Avenue du Pr Léon Bernard, Rennes, France
| | - Bruno Stieger
- Department of Clinical Pharmacology and Toxicology, University Hospital Zurich, University of Zurich, Rämistrasse 100, Zurich, Switzerland
| | - Claire Denizot
- Centre de Pharmacocinétique, Technologie Servier, 25–27 rue Eugène Vignat, Orléans, France
| | - Yannick Parmentier
- Centre de Pharmacocinétique, Technologie Servier, 25–27 rue Eugène Vignat, Orléans, France
| | - Sophie Potin
- Institut de Recherches en Santé, Environnement et Travail (IRSET), UMR INSERM U1085, Faculté de Pharmacie, 2 Avenue du Pr Léon Bernard, Rennes, France
- Pôle Pharmacie, Centre Hospitalier Universitaire, 2 rue Henri Le Guilloux, Rennes, France
| | - Olivier Fardel
- Institut de Recherches en Santé, Environnement et Travail (IRSET), UMR INSERM U1085, Faculté de Pharmacie, 2 Avenue du Pr Léon Bernard, Rennes, France
- Pôle Biologie, Centre Hospitalier Universitaire, 2 rue Henri Le Guilloux, Rennes, France
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Willemin ME, Desmots S, Le Grand R, Lestremau F, Zeman FA, Leclerc E, Moesch C, Brochot C. PBPK modeling of the cis- and trans-permethrin isomers and their major urinary metabolites in rats. Toxicol Appl Pharmacol 2016; 294:65-77. [DOI: 10.1016/j.taap.2016.01.011] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2015] [Revised: 01/12/2016] [Accepted: 01/16/2016] [Indexed: 12/16/2022]
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9
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Ratelle M, Côté J, Bouchard M. Toxicokinetics of permethrin biomarkers of exposure in orally exposed volunteers. Toxicol Lett 2015; 232:369-75. [DOI: 10.1016/j.toxlet.2014.12.003] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2014] [Revised: 11/27/2014] [Accepted: 12/04/2014] [Indexed: 11/15/2022]
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10
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Goksugur SB, Karatas Z, Goksugur N, Bekdas M, Demircioglu F. Metabolic acidosis in an infant associated with permethrin toxicity. Pediatr Dermatol 2015; 32:e15-7. [PMID: 25487692 DOI: 10.1111/pde.12473] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Pyrethroids are broad-spectrum insecticides. Permethrin intoxication due to topical application has not been documented in humans. We report a 20-month-old infant who had used 5% permethrin lotion topically for scabies treatment. Approximately 60 mL (20 mL/day) was used and after the third application he developed agitation, nausea, vomiting, respiratory distress, tachycardia, and metabolic acidosis. His clinical symptoms and metabolic acidosis normalized within 20 hours. His follow-up was unremarkable. Toxicity of permethrin is rare, and although permethrin is a widely and safely used topical agent in the treatment of scabies and lice, inappropriate use may rarely cause toxicity. Moreover, in cases of unexplained metabolic acidosis, topically applied medications should be carefully investigated.
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Affiliation(s)
- Sevil B Goksugur
- Department of Pediatrics, Medical Faculty, Abant Izzet Baysal University, Bolu, Turkey
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Tu W, Lu B, Niu L, Xu C, Lin C, Liu W. Dynamics of uptake and elimination of pyrethroid insecticides in zebrafish (Danio rerio) eleutheroembryos. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2014; 107:186-91. [PMID: 24952374 DOI: 10.1016/j.ecoenv.2014.05.013] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2014] [Revised: 05/12/2014] [Accepted: 05/13/2014] [Indexed: 05/15/2023]
Abstract
Synthetic pyrethroids (SPs) are among the most heavily used insecticides for residential and agricultural applications. Their residues have frequently been detected in aquatic ecosystems. Despite their high aquatic toxicity, their toxicokinetics are still unclear. In this study, the kinetics of uptake and depuration of three SPs, permethrin (PM), bifenthrin (BF) and λ-cyhalothrin (λ-CH), were determined for the first time using zebrafish eleutheroembryo assays. The diastereoisomer selectivity of PM in eleutheroembryos was further examined. The results indicated that three SPs were quickly taken up by eleutheroembryos. The bioaccumulation factors of the SPs ranged from 125.4 to 708.4. The depuration of SPs in zebrafish eleutheroembryos followed the first-order process. The elimination rate constants (k2) of SPs in eleutheroembryos ranged from 0.018 h(-1) to 0.0533 h(-1). The half-lives (t1/2) were in the range 13.0-38.5h. The diastereoisomer fraction (DF) values for PM in the eleutheroembryos estimated at different uptake and depuration times were all significantly greater than the original value (DF=0.43), indicating selective enrichment and elimination of cis-PM relative to trans-PM. These results reveal a high capacity for SP bioconcentration by zebrafish eleutheroembryos, suggesting that SPs possess a highly cumulative risk to fish.
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Affiliation(s)
- Wenqing Tu
- International Joint Research Center for Persistent Toxic Substances (IJRC-PTS), College of Biological and Environmental Engineering, Zhejiang University of Technology, Hangzhou 310032, China
| | - Bin Lu
- International Joint Research Center for Persistent Toxic Substances (IJRC-PTS), College of Biological and Environmental Engineering, Zhejiang University of Technology, Hangzhou 310032, China
| | - Lili Niu
- IJRC-PTS, MOE Key Laboratory of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Chao Xu
- International Joint Research Center for Persistent Toxic Substances (IJRC-PTS), College of Biological and Environmental Engineering, Zhejiang University of Technology, Hangzhou 310032, China.
| | - Chunmian Lin
- International Joint Research Center for Persistent Toxic Substances (IJRC-PTS), College of Biological and Environmental Engineering, Zhejiang University of Technology, Hangzhou 310032, China
| | - Weiping Liu
- IJRC-PTS, MOE Key Laboratory of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
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Côté J, Bonvalot Y, Carrier G, Lapointe C, Fuhr U, Tomalik-Scharte D, Wachall B, Bouchard M. A novel toxicokinetic modeling of cypermethrin and permethrin and their metabolites in humans for dose reconstruction from biomarker data. PLoS One 2014; 9:e88517. [PMID: 24586336 PMCID: PMC3935837 DOI: 10.1371/journal.pone.0088517] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2013] [Accepted: 01/06/2014] [Indexed: 11/18/2022] Open
Abstract
To assess exposure to pyrethroids in the general population, one of most widely used method nowadays consists of measuring urinary metabolites. Unfortunately, interpretation of data is limited by the unspecified relation between dose and levels in biological tissues and excreta. The objective of this study was to develop a common multi-compartment toxicokinetic model to predict the time courses of two mainly used pyrethroid pesticides, permethrin and cypermethrin, and their metabolites (cis-DCCA, trans-DCCA and 3-PBA) in the human body and in accessible biological matrices following different exposure scenarios. Toxicokinetics was described mathematically by systems of differential equations to yield the time courses of these pyrethroids and their metabolites in the different compartments. Unknown transfer rate values between compartments were determined from best fits to available human data on the urinary excretion time courses of metabolites following an oral and dermal exposure to cypermethrin in volunteers. Since values for these coefficients have not yet been determined, a mathematical routine was programmed in MathCad to establish the possible range of values on the basis of physiological and mathematical considerations. The best combination of parameter values was then selected using a statistic measure (reliability factor) along with a statistically acceptable range of values for each parameter. With this approach, simulations provided a close approximation to published time course data. This model allows to predict urinary time courses of trans-DCCA, cis-DCCA and 3-PBA, whatever the exposure route. It can also serve to reconstruct absorbed doses of permethrin or cypermethrin in the population using measured biomarker data.
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Affiliation(s)
- Jonathan Côté
- Département de santé environnementale et santé au travail, Chaire d'analyse et de gestion des risques toxicologiques and Institut de recherche en santé publique de l'Université de Montréal (IRSPUM), Université de Montréal, Montreal, Quebec, Canada
| | - Yvette Bonvalot
- Environmental Health Program, Health Canada, Longueuil, Quebec, Canada
| | - Gaétan Carrier
- Département de santé environnementale et santé au travail, Chaire d'analyse et de gestion des risques toxicologiques and Institut de recherche en santé publique de l'Université de Montréal (IRSPUM), Université de Montréal, Montreal, Quebec, Canada
| | - Caroline Lapointe
- Environmental Health Program, Health Canada, Longueuil, Quebec, Canada
| | - Uwe Fuhr
- Department of Pharmacology, University of Cologne, Clinical Pharmacology Unit, Köln, Germany
| | - Dorota Tomalik-Scharte
- Department of Pharmacology, University of Cologne, Clinical Pharmacology Unit, Köln, Germany
| | - Bertil Wachall
- Infectopharm Arzneimittel und Consilium GmbH, Heppenheim, Germany
| | - Michèle Bouchard
- Département de santé environnementale et santé au travail, Chaire d'analyse et de gestion des risques toxicologiques and Institut de recherche en santé publique de l'Université de Montréal (IRSPUM), Université de Montréal, Montreal, Quebec, Canada
- * E-mail:
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13
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Kegel P, Letzel S, Rossbach B. Biomonitoring in wearers of permethrin impregnated battle dress uniforms in Afghanistan and Germany. Occup Environ Med 2013; 71:112-7. [DOI: 10.1136/oemed-2012-101279] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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14
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Nutter T, Jiang N, Cooper BY. Persistent Na+ and K+ channel dysfunctions after chronic exposure to insecticides and pyridostigmine bromide. Neurotoxicology 2013; 39:72-83. [DOI: 10.1016/j.neuro.2013.08.006] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2013] [Revised: 08/07/2013] [Accepted: 08/11/2013] [Indexed: 12/15/2022]
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15
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Molecular and cellular influences of permethrin on mammalian nociceptors at physiological temperatures. Neurotoxicology 2013; 37:207-19. [DOI: 10.1016/j.neuro.2013.05.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2012] [Revised: 05/06/2013] [Accepted: 05/07/2013] [Indexed: 12/15/2022]
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16
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Giampreti A, Lampati L, Chidini G, Rocchi L, Rolandi L, Lonati D, Petrolini VM, Vecchio S, Locatelli CA, Manzo L. Recurrent tonic–clonic seizures and coma due to ingestion of Type I pyrethroids in a 19-month-old patient. Clin Toxicol (Phila) 2013; 51:497-500. [DOI: 10.3109/15563650.2013.808747] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Tornero-Velez R, Davis J, Scollon EJ, Starr JM, Setzer RW, Goldsmith MR, Chang DT, Xue J, Zartarian V, DeVito MJ, Hughes MF. A pharmacokinetic model of cis- and trans-permethrin disposition in rats and humans with aggregate exposure application. Toxicol Sci 2012; 130:33-47. [PMID: 22859315 DOI: 10.1093/toxsci/kfs236] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Permethrin is a broad-spectrum pyrethroid insecticide and among the most widely used insecticides in homes and crops. Managing the risks for pesticides such as permethrin depends on the ability to consider diverse exposure scenarios and their relative risks. Physiologically based pharmacokinetic models of delta methrin disposition were modified to describe permethrin kinetics in the rat and human. Unlike formulated deltamethrin which consists of a single stereoisomer, permethrin is formulated as a blend of cis- and trans-diastereomers. We assessed time courses for cis-permethrin and trans-permethrin in several tissues (brain, blood, liver, and fat) in the rat following oral administration of 1 and 10mg/kg permethrin (cis/trans: 40/60). Accurate simulation of permethrin in the rat suggests that a generic model structure is promising for modeling pyrethroids. Human in vitro data and appropriate anatomical information were used to develop a provisional model of permethrin disposition with structures for managing oral, dermal, and inhalation routes of exposure. The human permethrin model was used to evaluate dietary and residential exposures in the U.S. population as estimated by EPA's Stochastic Human Exposure and Dose Simulation model. Simulated cis- and trans-DCCA, metabolites of permethrin, were consistent with measured values in the National Health and Nutrition Examination Survey, indicating that the model holds promise for assessing population exposures and quantifying dose metrics.
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Affiliation(s)
- Rogelio Tornero-Velez
- NERL/ORD, U.S. Environmental Protection Agency, Research Triangle Park, North Carolina, USA.
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Vale A, Bradberry S, Proudfoot A. Clinical Toxicology of Insecticides. MAMMALIAN TOXICOLOGY OF INSECTICIDES 2012. [DOI: 10.1039/9781849733007-00312] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Some insects compete for our food, some damage construction materials and some are important disease vectors in humans and animals. Hence, it is not surprising that chemicals (insecticides) have been developed that kill insects and other arthropods. More recently introduced insecticides, such as the neonicotinoids, have been produced with the intent that humans and animals will not be harmed by their appropriate use. This chapter reviews the clinical features and management of exposure to organophosphorus (OP) and carbamate insecticides, neonicotinoids, phosphides and pyrethroids. In the developing world where the ambient temperature is often high and personal protection equipment often not worn, poisoning particularly from OP and carbamate insecticides is common in an occupational setting, though more severe cases are due to deliberate ingestion of these pesticides. Both of these insecticides produce the cholinergic syndrome. The neonicotinoids, a major new class of insecticide, were introduced on the basis that they were highly specific for subtypes of nicotinic receptors that occur only in insect tissues. However, deliberate ingestion of substantial amounts of a neonicotinoid has resulted in features similar to those found in nicotine (and OP and carbamate) poisoning, though the solvent in some formulations may have contributed to their toxicity. Phosphides interact with moisture in air (or with water or acid) to liberate phosphine, which is the active pesticide. Inhalation of phosphine, however, is a much less frequent cause of human poisoning than ingestion of a metal phosphide, though the toxicity by the oral route is also due to phosphine liberated by contact of the phosphide with gut fluids. It is then absorbed through the alimentary mucosa and distributed to tissues where it depresses mitochondrial respiration by inhibiting cytochrome c oxidase and other enzymes. Dermal exposure to pyrethroids may result in paraesthesiae, but systemic toxicity usually only occurs after ingestion, when irritation of the gastrointestinal tract and CNS toxicity, predominantly coma and convulsions, result.
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Affiliation(s)
- Allister Vale
- National Poisons Information Service (Birmingham Unit) City Hospital, Birmingham UK. *
- West Midlands Poisons Unit City Hospital, Birmingham UK
- School of Biosciences and College of Medical and Dental Sciences University of Birmingham, Birmingham UK
| | - Sally Bradberry
- National Poisons Information Service (Birmingham Unit) City Hospital, Birmingham UK. *
- West Midlands Poisons Unit City Hospital, Birmingham UK
- School of Biosciences and College of Medical and Dental Sciences University of Birmingham, Birmingham UK
| | - Alex Proudfoot
- National Poisons Information Service (Birmingham Unit) City Hospital, Birmingham UK. *
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Couture C, Fortin MC, Carrier G, Dumas P, Tremblay C, Bouchard M. Assessment of exposure to pyrethroids and pyrethrins in a rural population of the Montérégie area, Quebec, Canada. JOURNAL OF OCCUPATIONAL AND ENVIRONMENTAL HYGIENE 2009; 6:341-352. [PMID: 19306213 DOI: 10.1080/15459620902850907] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Pesticide use remains a preoccupation of the population and public health authorities given its possible impact on health. Pyrethroids can be listed among the widely used pesticides. The general population is potentially chronically exposed to pyrethroids mainly through food intake, but acute or sporadic exposures can also occur by other routes. Although pyrethroids are considered among the least toxic pesticides, their neurotoxic properties can affect humans, but current exposure levels in the population of Quebec are not known. The study thus aimed at assessing pyrethroid exposure in a rural, agricultural population during summer through measurements of urinary biomarkers. A total of 163 volunteers, 49 children and 114 adults, living in the Montérégie area of Quebec, participated in the study, which took place from June to August 2006, the period of intensive application of pesticides. Participants were asked to collect all their micturitions from 6 p.m. until the next morning, including first morning void, and to fill out a questionnaire to document factors that could potentially contribute to exposure. A gas-chromatography mass-spectrometry method was used to quantify six urinary metabolites resulting from pyrethroid biotransformation: cis- and trans-2,2-(dichlorovinyl)-2,2-dimethylcyclopropane carboxylic acid (cDCCA and tDCCA), 3-phenoxybenzoic acid (PBA), chrysanthemum dicarboxylic acid (CDCA), cis-2,2-(dibromovinyl)-2,2-dimethylcyclopropane carboxylic acid (DBCA) and 4-fluoro-3-phenoxybenzoic acid (FPBA). Distributions of amounts of the six metabolites excreted per unit of body weight, during a standardized 12-hr period, followed the same decreasing pattern in adults and in children: tDCCA > PBA > cDCCA > CDCA > DBCA > FPBA. No statistically significant difference was observed between the two groups, but amounts of metabolites varied greatly among individuals, suggesting important interindividual variations in the absorbed doses of these compounds. No consistent associations were observed between the excretion of correlated metabolites and the various factors documented by questionnaire (personal factors, life habits, sources of exposure). Comparison of the current data with those observed in an urban population of the same province during the summer of 2005 suggests a greater summertime exposure to some pyrethroids in the rural population.
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Affiliation(s)
- Caroline Couture
- Département de santé environnementale et santé au travail, Faculté de Médecine, Université de Montréal, Montréal, Québec, Canada
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Abstract
Pyrethroid insecticides have a wide variety of applications throughout the world. They are structurally diverse chemicals that are synthetically derived from naturally occurring pyrethrin insecticides. Significant advances in analytical chemistry have led to the development of biomarkers of exposure to pyrethroids, and these methods are currently being applied to study exposure in the general population. This article reviews the chemistry and toxicology of pyrethroid insecticides, with an emphasis on the development of biomarkers to assess environmental exposure. Future challenges in the application of these biomarkers in epidemiological studies are explored, as is a need for improved understanding of the toxicokinetics of pyrethroids in humans.
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Affiliation(s)
- Daniel L Sudakin
- Department of Environmental and Molecular Toxicology, Oregon State University, Corvallis, Oregon 97331-6502, USA.
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21
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Permethrin may induce adult male mouse reproductive toxicity due to cis isomer not trans isomer. Toxicology 2008; 248:136-41. [DOI: 10.1016/j.tox.2008.03.018] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2008] [Revised: 03/24/2008] [Accepted: 03/25/2008] [Indexed: 10/22/2022]
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Appel KE, Gundert-Remy U, Fischer H, Faulde M, Mross KG, Letzel S, Rossbach B. Risk assessment of Bundeswehr (German Federal Armed Forces) permethrin-impregnated battle dress uniforms (BDU). Int J Hyg Environ Health 2008; 211:88-104. [DOI: 10.1016/j.ijheh.2007.10.005] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2007] [Revised: 10/18/2007] [Accepted: 10/18/2007] [Indexed: 11/30/2022]
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Nishi K, Huang H, Kamita SG, Kim IH, Morisseau C, Hammock BD. Characterization of pyrethroid hydrolysis by the human liver carboxylesterases hCE-1 and hCE-2. Arch Biochem Biophys 2006; 445:115-23. [PMID: 16359636 PMCID: PMC1444892 DOI: 10.1016/j.abb.2005.11.005] [Citation(s) in RCA: 89] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2005] [Revised: 11/11/2005] [Accepted: 11/13/2005] [Indexed: 11/23/2022]
Abstract
Carboxylesterases hydrolyze a large array of endogenous and exogenous ester-containing compounds, including pyrethroid insecticides. Herein, we report the specific activities and kinetic parameters of human carboxylesterase (hCE)-1 and hCE-2 using authentic pyrethroids and pyrethroid-like, fluorescent surrogates. Both hCE-1 and hCE-2 hydrolyzed type I and II pyrethroids with strong stereoselectivity. For example, the trans-isomers of permethrin and cypermethrin were hydrolyzed much faster than corresponding cis-counterparts by both enzymes. Kinetic values of hCE-1 and hCE-2 were determined using cypermethrin and 11 stereoisomers of the pyrethroid-like, fluorescent surrogates. K(m) values for the authentic pyrethroids and fluorescent surrogates were in general lower than those for other ester-containing substrates of hCEs. The pyrethroid-like, fluorescent surrogates were hydrolyzed at rates similar to the authentic pyrethroids by both enzymes, suggesting the potential of these compounds as tools for high throughput screening of esterases that hydrolyze pyrethroids.
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Affiliation(s)
- Kosuke Nishi
- Department of Entomology and UC Davis Cancer Center, University of California, Davis, CA 95616, USA
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Huang H, Fleming CD, Nishi K, Redinbo MR, Hammock BD. Stereoselective hydrolysis of pyrethroid-like fluorescent substrates by human and other mammalian liver carboxylesterases. Chem Res Toxicol 2005; 18:1371-7. [PMID: 16167828 PMCID: PMC1444893 DOI: 10.1021/tx050072+] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Mammalian hepatic carboxylesterases (CEs) play important roles in the detoxification of ester-containing pyrethroids, which are widely used for the control of agricultural pests and disease vectors such as mosquitoes. Pyrethroids and pyrethroid-like fluorescent substrates exhibit a consistent pattern of stereoselective hydrolysis by a recombinant murine hepatic CE. We sought to understand whether this pattern is maintained in other hepatic CEs and to unravel the origin of the stereoselectivity. We found that all hepatic CEs tested displayed a consistent pattern of stereoselective hydrolysis: the chiral center(s) in the acid moiety more strongly influenced stereoselective hydrolysis than the chiral center in the alcohol moiety. For cypermethrin analogues with a cyclopropane ring in the acid moiety, trans-isomers were generally hydrolyzed faster than the corresponding cis-isomers. For fenvalerate analogues without a cyclopropane ring in the acid moiety, 2R-isomers were better substrates than 2S-isomers. These general hydrolytic patterns were examined by modeling the pyrethroid-like analogues within the active site of the crystal structure of human carboxylesterase 1 (hCE1). Stereoselective steric clashes were found to occur between the acid moieties and either the catalytic Ser loop (residues 219-225) or the oxyanion hole (residues140-144). These clashes appeared to explain the stereopreference between trans- and cis-isomers of cypermethrin analogues, and the 2R- and 2S-isomers of fenvalerate analogues by hCE1. The implications these findings have on the design and use of effective pesticides are discussed.
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Affiliation(s)
- Huazhang Huang
- Department of Entomology and Cancer Research Center, University of California, Davis, California 95616, USA
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25
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Abstract
The first pyrethroid pesticide, allethrin, was identified in 1949. Allethrin and other pyrethroids with a basic cyclopropane carboxylic ester structure are type I pyrethroids. The insecticidal activity of these synthetic pyrethroids was enhanced further by the addition of a cyano group to give alpha-cyano (type II) pyrethroids, such as cypermethrin. The finding of insecticidal activity in a group of phenylacetic 3-phenoxybenzyl esters, which lacked the cyclopropane ring but contained the alpha-cyano group (and hence were type II pyrethroids) led to the development of fenvalerate and related compounds. All pyrethroids can exist as at least four stereoisomers, each with different biological activities. They are marketed as racemic mixtures or as single isomers. In commercial formulations, the activity of pyrethroids is usually enhanced by the addition of a synergist such as piperonyl butoxide, which inhibits metabolic degradation of the active ingredient. Pyrethroids are used widely as insecticides both in the home and commercially, and in medicine for the topical treatment of scabies and headlice. In tropical countries mosquito nets are commonly soaked in solutions of deltamethrin as part of antimalarial strategies. Pyrethroids are some 2250 times more toxic to insects than mammals because insects have increased sodium channel sensitivity, smaller body size and lower body temperature. In addition, mammals are protected by poor dermal absorption and rapid metabolism to non-toxic metabolites. The mechanisms by which pyrethroids alone are toxic are complex and become more complicated when they are co-formulated with either piperonyl butoxide or an organophosphorus insecticide, or both, as these compounds inhibit pyrethroid metabolism. The main effects of pyrethroids are on sodium and chloride channels. Pyrethroids modify the gating characteristics of voltage-sensitive sodium channels to delay their closure. A protracted sodium influx (referred to as a sodium 'tail current') ensues which, if it is sufficiently large and/or long, lowers the action potential threshold and causes repetitive firing; this may be the mechanism causing paraesthesiae. At high pyrethroid concentrations, the sodium tail current may be sufficiently great to prevent further action potential generation and 'conduction block' ensues. Only low pyrethroid concentrations are necessary to modify sensory neurone function. Type II pyrethroids also decrease chloride currents through voltage-dependent chloride channels and this action probably contributes the most to the features of poisoning with type II pyrethroids. At relatively high concentrations, pyrethroids can also act on GABA-gated chloride channels, which may be responsible for the seizures seen with severe type II poisoning. Despite their extensive world-wide use, there are relatively few reports of human pyrethroid poisoning. Less than ten deaths have been reported from ingestion or following occupational exposure. Occupationally, the main route of pyrethroid absorption is through the skin. Inhalation is much less important but increases when pyrethroids are used in confined spaces. The main adverse effect of dermal exposure is paraesthesiae, presumably due to hyperactivity of cutaneous sensory nerve fibres. The face is affected most commonly and the paraesthesiae are exacerbated by sensory stimulation such as heat, sunlight, scratching, sweating or the application of water. Pyrethroid ingestion gives rise within minutes to a sore throat, nausea, vomiting and abdominal pain. There may be mouth ulceration, increased secretions and/or dysphagia. Systemic effects occur 4-48 hours after exposure. Dizziness, headache and fatigue are common, and palpitations, chest tightness and blurred vision less frequent. Coma and convulsions are the principal life-threatening features. Most patients recover within 6 days, although there were seven fatalities among 573 cases in one series and one among 48 cases in another. Management is supportive. As paraesthesiae usually resolve in 12-24 hours, specific treatment is not generally required, although topical application of dl-alpha tocopherol acetate (vitamin E) may reduce their severity.
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Affiliation(s)
- Sally M Bradberry
- National Poisons Information Service (Birmingham Centre), City Hospital, UK
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26
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Soderlund DM, Clark JM, Sheets LP, Mullin LS, Piccirillo VJ, Sargent D, Stevens JT, Weiner ML. Mechanisms of pyrethroid neurotoxicity: implications for cumulative risk assessment. Toxicology 2002; 171:3-59. [PMID: 11812616 DOI: 10.1016/s0300-483x(01)00569-8] [Citation(s) in RCA: 581] [Impact Index Per Article: 26.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The Food Quality Protection Act (FQPA) of 1996 requires the United States Environmental Protection Agency to consider the cumulative effects of exposure to pesticides having a 'common mechanism of toxicity.' This paper reviews the information available on the acute neurotoxicity and mechanisms of toxic action of pyrethroid insecticides in mammals from the perspective of the 'common mechanism' statute of the FQPA. The principal effects of pyrethroids as a class are various signs of excitatory neurotoxicity. Historically, pyrethroids were grouped into two subclasses (Types I and II) based on chemical structure and the production of either the T (tremor) or CS (choreoathetosis with salivation) intoxication syndrome following intravenous or intracerebral administration to rodents. Although this classification system is widely employed, it has several shortcomings for the identification of common toxic effects. In particular, it does not reflect the diversity of intoxication signs found following oral administration of various pyrethroids. Pyrethroids act in vitro on a variety of putative biochemical and physiological target sites, four of which merit consideration as sites of toxic action. Voltage-sensitive sodium channels, the sites of insecticidal action, are also important target sites in mammals. Unlike insects, mammals have multiple sodium channel isoforms that vary in their biophysical and pharmacological properties, including their differential sensitivity to pyrethroids. Pyrethroids also act on some isoforms of voltage-sensitive calcium and chloride channels, and these effects may contribute to the toxicity of some compounds. Effects on peripheral-type benzodiazepine receptors are unlikely to be a principal cause of pyrethroid intoxication but may contribute to or enhance convulsions caused by actions at other target sites. In contrast, other putative target sites that have been identified in vitro do not appear to play a major role in pyrethroid intoxication. The diverse toxic actions and pharmacological effects of pyrethroids suggest that simple additivity models based on combined actions at a single target are not appropriate to assess the risks of cumulative exposure to multiple pyrethroids.
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Affiliation(s)
- David M Soderlund
- Department of Entomology, New York State Agricultural Experiment Station, Cornell University, Geneva, NY 14456, USA.
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