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Journal of Toxicology and Environmental... 2003Methyl parathion is an organophosphorus (OP) insecticide with insecticidal properties derived from acetylcholinesterase (AChE) inhibition; this same property is also the... (Review)
Review
Methyl parathion is an organophosphorus (OP) insecticide with insecticidal properties derived from acetylcholinesterase (AChE) inhibition; this same property is also the root of its toxicity in humans. Poisoning with methyl parathion leads to cholinergic overstimulation with signs of toxicity including sweating, dizziness, vomiting, diarrhea, convulsions, cardiac arrest, respiratory arrest, and, in extreme cases, death. Reports of methyl parathion intoxication, usually seen only in field pesticide applicators, have increased throughout the United States as a result of unauthorized application of methyl parathion inside homes. The health concerns of the use of methyl parathion have resulted in cancellation of its use in most food crops in the United States. This review examines the well-documented neurotoxicity of methyl parathion as well as effects on other organ systems.
Topics: Animals; Diarrhea; Disease Models, Animal; Dizziness; Environmental Exposure; Genetic Predisposition to Disease; Heart Arrest; Humans; Inactivation, Metabolic; Insecticides; Metabolic Clearance Rate; Methyl Parathion; Neurotoxicity Syndromes; Poisoning; Respiratory Insufficiency; Seizures; Skin Absorption; Sweating; Tissue Distribution; United States; Vomiting
PubMed: 12554434
DOI: 10.1080/10937400306471 -
Reviews on Environmental Health 2006Methyl parathion (MP), a toxic organophosphate insecticide approved for outdoor use only, is classified by the World Health Organization (WHO) as a Category Ia... (Review)
Review
Methyl parathion (MP), a toxic organophosphate insecticide approved for outdoor use only, is classified by the World Health Organization (WHO) as a Category Ia (extremely toxic) and by the United States Environmental Protection Agency (U.S. EPA) as a Toxicity Category I (most toxic) insecticide. In several U.S. states in the late 1980s and early 1990s, toxic exposures were created by the illegal use of MP indoors by uncertified pest control operators. As the health effects of MP exposure became evident with increasing public awareness, intervention by the U.S. government, in collaboration with several agencies and public initiatives, led to investigations of MP exposure. After evidence of MP metabolites from urine samples confirmed the exposure, in 1998 the indoor use of MP was banned in the U.S. to protect human health, especially that of children, and the environment. Toxic exposures to MP also occurred in developing countries. In El Salvador, occupational exposure to MP in farmers introduced environmental exposures among agricultural families, who presented with the cholinergic features of MP toxicity. Suicidal MP poisoning was reported in Nepal. A fatal accidental poisoning in children in Peru reflected the serious health risk of pesticides in developing countries. The negligence of pesticide exporters raised human rights issues over the tragedy. Nevertheless, MP exposure remains a potential health risk in both the U.S. and the developing world. Preventive measures in reducing the use of toxic chemicals should be taken seriously to protect human health and the environment.
Topics: Air Pollution; Environmental Exposure; Humans; Insecticides; Methyl Parathion; Organophosphorus Compounds; Water Pollution, Chemical
PubMed: 16700430
DOI: 10.1515/reveh.2006.21.1.57 -
Zhonghua Yi Xue Za Zhi = Chinese... May 2002Methyl parathion and other organophosphorus insecticides are widely used in agriculture. Poisonings to this class of compounds are common and exerted primarily through... (Review)
Review
Methyl parathion and other organophosphorus insecticides are widely used in agriculture. Poisonings to this class of compounds are common and exerted primarily through inhibition of acetylcholinesterase. Methyl parathion became a major health concern when it was illegally sprayed in private homes. Since there are limited data with which to predict the long-term effects resulting from a pattern of exposure to methyl parathion that may have occurred in domestic settings, studies were performed to compare its pharmacokinetics and pharmacodynamics after intravenous, oral or dermal exposure. Methyl parathion was given to adult female rats as a single dose intravenously (2.5 mg/kg) through a femoral catheter, orally (2.5 mg/kg) by gavage, or dermally (< or = 50 mg/kg) by application to shaved skin at the nape of the neck. Blood (200 microl) was collected at increasing times from a separate catheter or from the retro-orbital sinus. Cholinesterase activity was measured in blood and normalized to hemoglobin content, whereas activities in brain and peripheral tissues were normalized to protein. Blood methyl parathion was quantitated by gas chromatography-electron capture. The pharmacokinetics of methyl parathion after intravenous exposure best fit a model in which it was distributed between two compartments and rapidly eliminated. Maximal concentrations of methyl parathion ranged from 200 to 350 ng/ml. The half-life of methyl parathion was 51 minutes, its volume of distribution was 10.1 L/kg, and clearance was 108 ml/min/kg. The kinetics of methyl parathion after single oral exposure contrasted with those after intravenous exposure. Despite a high absorption coefficient, oral bioavailability of methyl parathion was less than 5%, and concentrations in blood were 2% or less of those after intravenous exposure. After single dermal exposure (25 or 50 mg/kg), blood methyl parathion levels increased during the first 6 h and then remained constant for the next 42 h at about 150 ng/ml. Despite differences in its pharmacokinetics, methyl parathion caused similar time-dependent changes in blood and brain cholinesterase activities after intravenous or oral administration. Maximal inhibition of blood cholinesterase occurred within 15-60 min, and activities recovered within 30 - 48 h. In contrast, inhibition of blood cholinesterase caused by single dermal exposure (> or = 25 mg/kg) to methyl parathion developed gradually over 24 h, but was sustained. Cholinesterase inhibited by a lower dose (< or = 12 mg/kg) of methyl parathion required up to 21 days to recover fully. The pharmacokinetics and pharmacodynamics of methyl parathion are complex, and the complexity varies with the route of exposure. A significant 'first pass' effect for methyl parathion is seen with oral administration. Dermal exposure to methyl parathion, as likely occurred with the illegal spraying of private homes and businesses, may exacerbate toxicity and increase the potential for long-term adverse health effects.
Topics: Animals; Cholinesterases; Humans; Insecticides; Methyl Parathion
PubMed: 12166762
DOI: No ID Found -
Spectrochimica Acta. Part A, Molecular... Mar 2022A colorimetric gold nanoparticles (AuNPs)-based acetylcholinesterase (AChE) assay was designed for the first time to measure the concentration of parathion-methyl (PM)...
A colorimetric gold nanoparticles (AuNPs)-based acetylcholinesterase (AChE) assay was designed for the first time to measure the concentration of parathion-methyl (PM) in lake water samples. In this assay, the analyte PM inhibited the hydrolysis of acetylthiocholine (ATCh) by AChE, preventing the formation of thiocholine (TCh) that would otherwise react with the AuNPs catalyst and deactivate the catalyst. Therefore, in the presence of PM, the AuNPs catalyzed the oxidation of the 3,3',5,5'-tetramethylbenzidine (TMB) colorimetric indicator to oxTMB, inducing a visual color change from colorless to blue. However, in the absence of PM, AChE hydrolyzed ATCh to TCh, which then reacted with the AuNPs, preventing the oxidation of TMB to oxTMB and rendering the solution colorless. Therefore, the change in the color of the analyte solution indicated the presence of PM, and the absorbance of the resulting solution was measured by UV-Vis spectroscopy to calculate the concentration of PM after generation of a calibration curve. This method was then employed using the smartphone app Color Picker, which converted the color information from the photos of the solution into digital red (R), green (G), and blue (B) values. The ratio of green (G) to blue (B) (G/B) was then plotted against the corresponding concentration to calculate the standard curve, whose regression equation was expressed by y = -0.012x + 1.02 (ng/mL), and the coefficient of determination (R) was 0.97. In addition, this method was also used to determine the amount of PM in real lake water samples with recovery of 90.2-133.3%.
Topics: Acetylcholinesterase; Colorimetry; Gold; Metal Nanoparticles; Methyl Parathion
PubMed: 34865979
DOI: 10.1016/j.saa.2021.120665 -
IARC Monographs on the Evaluation of... Jan 1983
Topics: Animals; Carcinogens; Carcinogens, Environmental; Chemical Phenomena; Chemistry; Humans; Methyl Parathion; Mutagens; Parathion; Reproduction
PubMed: 6578177
DOI: No ID Found -
Chemosphere May 2016Methyl parathion, a widely used insecticide around the world, has aroused gradually extensive concern of researchers due to its degradation product such as methyl...
Methyl parathion, a widely used insecticide around the world, has aroused gradually extensive concern of researchers due to its degradation product such as methyl paraoxon, with higher toxicity for mammals and more recalcitrant. Given the ubiquity of manganese dioxide (MnO2) in soils and aquatic sediments, the abiotic degradation of methyl parathion by α-MnO2 was investigated in batch experiments. It was found that methyl parathion was decomposed up to 90% by α-MnO2 in 30 h and the removal efficiency of methyl parathion depended strongly on the loading of α-MnO2 and pH value in the solution where the reactions followed pseudo-first-order model well. The coexisting metal ions (such as Ca(2+), Mg(2+) and Mn(2+)) weakened markedly the degradation of methyl parathion by α-MnO2. However, the effect of dissolved organic matter (HA-Na) on reaction rates presented two sides: to improve hydrolysis rate but deteriorate oxidation rate of methyl parathion. Based on the degradation products identified by gas chromatography-mass spectrometer (GC/MS) and liquid chromatography high-resolution mass spectrometer (LC/HRMS), both hydrolysis and oxidation processes were proposed to be two predominant reaction mechanisms contributing to methyl parathion degradation by α-MnO2. This study provided meaningful information to elucidate the abiotic dissipation of methyl parathion by manganese oxide minerals in the environment.
Topics: Animals; Environmental Pollutants; Environmental Restoration and Remediation; Gas Chromatography-Mass Spectrometry; Hydrogen-Ion Concentration; Hydrolysis; Insecticides; Kinetics; Manganese Compounds; Methyl Parathion; Models, Chemical; Oxidation-Reduction; Oxides
PubMed: 26891361
DOI: 10.1016/j.chemosphere.2016.02.028 -
Pesticide Biochemistry and Physiology Oct 2022Methyl parathion is an organophosphorus pesticide widely employed worldwide to control pests in agricultural and domestic environments. However, due to its intensive...
Methyl parathion is an organophosphorus pesticide widely employed worldwide to control pests in agricultural and domestic environments. However, due to its intensive use, high toxicity, and environmental persistence, methyl parathion is recognized as an important ecosystem and human health threat, causing severe environmental pollution events and numerous human poisoning and deaths each year. Therefore, identifying and characterizing microorganisms capable of fully degrading methyl parathion and its degradation metabolites is a crucial environmental task for the bioremediation of pesticide-polluted sites. Burkholderia zhejiangensis CEIB S4-3 is a bacterial strain isolated from agricultural soils capable of immediately hydrolyzing methyl parathion at a concentration of 50 mg/L and degrading the 100% of the released p-nitrophenol in a 12-hour lapse when cultured in minimal salt medium. In this study, a comparative proteomic analysis was conducted in the presence and absence of methyl parathion to evaluate the biological mechanisms implicated in the methyl parathion biodegradation and resistance by the strain B. zhejiangensis CEIB S4-3. In each treatment, the changes in the protein expression patterns were evaluated at three sampling times, zero, three, and nine hours through the use of two-dimensional polyacrylamide gel electrophoresis (2D-PAGE), and the differentially expressed proteins were identified by mass spectrometry (MALDI-TOF). The proteomic analysis allowed the identification of 72 proteins with differential expression, 35 proteins in the absence of the pesticide, and 37 proteins in the experimental condition in the presence of methyl parathion. The identified proteins are involved in different metabolic processes such as the carbohydrate and amino acids metabolism, carbon metabolism and energy production, fatty acids β-oxidation, and the aromatic compounds catabolism, including enzymes of the both p-nitrophenol degradation pathways (Hydroquinone dioxygenase and Hydroxyquinol 1,2 dioxygenase), as well as the overexpression of proteins implicated in cellular damage defense mechanisms such as the response and protection of the oxidative stress, reactive oxygen species defense, detoxification of xenobiotics, and DNA repair processes. According to these data, B. zhejiangensis CEIB S4-3 overexpress different proteins related to aromatic compounds catabolism and with the p-nitrophenol degradation pathways, the higher expression levels observed in the two subunits of the enzyme Hydroquinone dioxygenase, suggest a preferential use of the Hydroquinone metabolic pathway in the p-nitrophenol degradation process. Moreover the overexpression of several proteins implicated in the oxidative stress response, xenobiotics detoxification, and DNA damage repair reveals the mechanisms employed by B. zhejiangensis CEIB S4-3 to counteract the adverse effects caused by the methyl parathion and p-nitrophenol exposure.
Topics: Amino Acids; Burkholderiaceae; Carbohydrates; Carbon; Dioxygenases; Ecosystem; Fatty Acids; Hydroquinones; Methyl Parathion; Nitrophenols; Organophosphorus Compounds; Pesticides; Proteomics; Reactive Oxygen Species; Soil
PubMed: 36127069
DOI: 10.1016/j.pestbp.2022.105197 -
Food Chemistry Aug 2022Porous carbon spheres (PCS) derived from expired sugarcane juice (SJ) and modified with β-cyclodextrin (β-CD) were used for the fabrication of SJPCS@β-CD/GCE sensor...
Rapid determination of methyl parathion in vegetables using electrochemical sensor fabricated from biomass-derived and β-cyclodextrin functionalized porous carbon spheres.
Porous carbon spheres (PCS) derived from expired sugarcane juice (SJ) and modified with β-cyclodextrin (β-CD) were used for the fabrication of SJPCS@β-CD/GCE sensor with glassy carbon electrode (GCE) to detect methyl parathion (MP). SJPCS with interconnected porous structure exhibits excellent electrical conductivity, strong adsorption property, and high specific surface area, while β-CD with molecular recognition property achieves the uniform dispersion of SJPCS and promotes the recognition and adsorption of MP molecules. Thanks to the synergistic combination of SJPCS and β-CD, the SJPCS@β-CD/GCE sensor exhibited respectable MP determination performance with low limit of detection of 5.87 nM in the MP concentration range of 0.01-10 µM. For the MP detection in vegetables (onion, cabbage, spinach), the fabricated sensor showed good practicability with adequate relative standard deviation of 1.06% to 4.25% and satisfactory recoveries of 96.5 to 100.5%. A promising strategy for the rapid determination of methyl parathion in food products was developed.
Topics: Biomass; Carbon; Electrochemical Techniques; Electrodes; Methyl Parathion; Porosity; Vegetables; beta-Cyclodextrins
PubMed: 35413778
DOI: 10.1016/j.foodchem.2022.132643 -
Environmental Health Perspectives Jul 1997
Topics: Air Pollution, Indoor; Community Participation; Environmental Exposure; Humans; Insecticides; Methyl Parathion; Public Health; Residence Characteristics; United States; United States Environmental Protection Agency
PubMed: 9294711
DOI: 10.1289/ehp.105-1470095 -
Food Chemistry Jul 2023A highly sensitive fluorescent sensing system of novel carbon quantum dots nano-fluorescent probe based on corn stalks was established for the determination of methyl...
A highly sensitive fluorescent sensing system of novel carbon quantum dots nano-fluorescent probe based on corn stalks was established for the determination of methyl parathion by alkaline catalytic hydrolysis and inner filter effect mechanism. The carbon quantum dots nano-fluorescent probe was prepared from corn stalks using an optimized one-step hydrothermal method. The detection mechanism of methyl parathion was revealed. The reaction conditions were optimized. The linear range, sensitivity and selectivity of the method were evaluated. Under the optimal conditions, the carbon quantum dots nano-fluorescent probe exhibited high selectivity and sensitivity to methyl parathion, achieving a linear range of 0.005-14 µg/mL. The fluorescence sensing platform was applied to the detection of methyl parathion in rice samples, and the results showed that the recoveries range from 91.64 to 104.28 %, and the relative standard deviations were less than 4.17 %. The detection limit for methyl parathion in rice samples was 1.22 µg/kg, and the limit of quantitation (LOQ) was 4.07 µg/kg, which was very satisfactory.
Topics: Methyl Parathion; Quantum Dots; Oryza; Carbon; Limit of Detection; Spectrometry, Fluorescence; Fluorescent Dyes
PubMed: 36796262
DOI: 10.1016/j.foodchem.2023.135679