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Ultrasonics Sonochemistry Sep 2006The degradation of methyl parathion (O,O-dimethyl-O-(4-nitrophenyl)-phosphorothioate) using anatase titanium dioxide (TiO(2)) powder as heterogeneous sonocatalysts is...
Sonocatalytic degradation of methyl parathion in the presence of nanometer and ordinary anatase titanium dioxide catalysts and comparison of their sonocatalytic abilities.
The degradation of methyl parathion (O,O-dimethyl-O-(4-nitrophenyl)-phosphorothioate) using anatase titanium dioxide (TiO(2)) powder as heterogeneous sonocatalysts is reported. The influences of reaction parameters such as the species of TiO(2) sonocatalysts, methyl parathion concentrations, TiO(2) adding amount, pH, ultrasonic intensity, ultrasonic frequency and temperature have been investigated and the optimal conditions for eliminating methyl parathion have been identified. The efficiencies of sonocatalytic degradation in both nanometer and ordinary anatase systems are compared and the results indicate that the sonocatalytic activity of nanometer anatase TiO(2) powder is better than that of ordinary anatase TiO(2) powder. The primary degradation and the total mineralization of methyl parathion have been monitored by high performance liquid chromatography (HPLC) and UV-vis spectra, respectively. Methyl parathion got destroyed to some extent in both nanometer and ordinary anatase systems under ultrasonic irradiation. The kinetics for the degradation process of methyl parathion follows the first-order reaction. The degradation ratio of methyl parathion surpassed 90% within 50min in the optimal experiment conditions.
Topics: Catalysis; Chromatography, High Pressure Liquid; Dose-Response Relationship, Drug; Hydrogen-Ion Concentration; Kinetics; Methyl Parathion; Microscopy, Electron, Transmission; Models, Chemical; Nanotechnology; Temperature; Titanium; Ultrasonics; Ultraviolet Rays; Water Pollutants, Chemical
PubMed: 16413995
DOI: 10.1016/j.ultsonch.2005.11.002 -
RSC Advances Oct 2022Zr(CUR)/NiCoS/CuCoS and Zr(CUR)/CuCoS/AgS ternary composites were synthesized as efficient photocatalysts, and well characterized through XRD, FTIR, DRS, FE-SEM, EDS,...
Performance evaluation of Zr(CUR)/NiCoS/CuCoS and Zr(CUR)/CuCoS/AgS composites for photocatalytic degradation of the methyl parathion pesticide using a spiral-shaped photocatalytic reactor.
Zr(CUR)/NiCoS/CuCoS and Zr(CUR)/CuCoS/AgS ternary composites were synthesized as efficient photocatalysts, and well characterized through XRD, FTIR, DRS, FE-SEM, EDS, and EDS mapping techniques. The potential of a spiral-shaped photocatalytic reactor was evaluated for degradation of the methyl parathion (MP) pesticide using synthesized photocatalysts under visible light irradiation. Computational fluid dynamics (CFD) was applied for analysis of the hydrodynamics behaviour and mass transport occurring inside the reactor. The experiments were performed based on a developed CCD-RSM model, while the desirability function (DF) was used for optimization of the process. Findings showed that the highest MP degradation percentage was 98.70% at optimal operating values including 20 mg L, 0.60 g L, 8 and 40 min for MP concentration, catalyst dosage, pH, and reaction time, respectively. This study clearly demonstrated that high degradation efficiency can be achieved using a spiral-shaped photocatalytic reactor rather than a traditional annular reactor at same conditions. The increase in reaction rate is related to the higher average turbulence kinetic energy in the spiral-shaped reactor over the traditional reactor, which results in the increased diffusivity and improves the mass and momentum transfer.
PubMed: 36320776
DOI: 10.1039/d2ra06277a -
TheScientificWorldJournal 2012A reliable and sensitive headspace solid-phase microextraction gas chromatography-mass spectrometry method for simultaneous determination of different organophosphorus...
Simultaneous determination of parathion, malathion, diazinon, and pirimiphos methyl in dried medicinal plants using solid-phase microextraction fibre coated with single-walled carbon nanotubes.
A reliable and sensitive headspace solid-phase microextraction gas chromatography-mass spectrometry method for simultaneous determination of different organophosphorus pesticides in dried medicinal plant samples is described. The analytes were extracted by single-walled carbon nanotubes as a new solid-phase microextraction adsorbent. The developed method showed good performance. For diazinon and pirimiphos methyl calibration, curves were linear (r(2) ≥ 0.993) over the concentration ranges from 1.5 to 300 ng g(-1), and the limit of detection at signal-to-noise ratio of 3 was 0.3 ng g(-1). For parathion and malathion, the linear range and limit of detection were 2.5-300 (r(2) ≥ 0.991) and 0.5 ng g(-1), respectively. In addition, a comparative study between the single-walled carbon nanotubes and a commercial polydimethylsiloxane fibre for the determination of target analytes was carried out. Single-walled carbon nanotubes fibre showed higher extraction capacity, better thermal stability (over 350 °C), and longer lifespan (over 250 times) than the commercial polydimethylsiloxane fibre. The developed method was successfully applied to determine target organophosphorus pesticides in real samples.
Topics: Calibration; Diazinon; Dimethylpolysiloxanes; Limit of Detection; Malathion; Nanotechnology; Nanotubes, Carbon; Organophosphorus Compounds; Organothiophosphorus Compounds; Parathion; Pesticides; Plants, Medicinal; Reproducibility of Results; Solid Phase Microextraction; Temperature
PubMed: 22645439
DOI: 10.1100/2012/627607 -
Marine Environmental Research Jul 2008Induction of many genes encoding detoxifying enzymes and antioxidant proteins is mediated through a common mechanism, which is controlled by electrophile-responsive...
Initial results in the development of a reporter cell line for toxicology studies at gene expression level: activation of the electrophile-responsive element by copper and methyl parathion.
Induction of many genes encoding detoxifying enzymes and antioxidant proteins is mediated through a common mechanism, which is controlled by electrophile-responsive elements (EpRE) within the regulatory region of those genes. Copper and methyl parathion are environmental pollutants known to induce the expression of EpRE-mediated genes. In order to evaluate the molecular response triggered by these pollutants, a stable cell line was produced, which carries a transgene comprised of the green fluorescent protein (GFP) reporter gene under transcriptional control of the mouse glutathione-S-transferase (gst1) electrophile-responsive element fused to the mouse metallothionein (mt1) minimal promoter. The rat HTC hepatoma cells were transfected with the EpREmt-GFP construct and successfully selected with G418 antibiotic. EpREmt-GFP HTC cells were treated with 0.002 mg L(-1), 0.02 mg L(-1), 0.2 mg L(-1) and 2 mg L(-1) copper sulfate and 0.001 mg L(-1), 0.01 mg L(-1), 0.1 mg L(-1) and 1 mg L(-1) methyl parathion for 48 h. GFP expression was directly quantified in living cells using a microplate fluorimeter. GFP expression was significantly increased in higher concentrations of both pollutants, showing a 1.80- and 2.58-fold induction of GFP at 2mg copper L(-1) and 1mg methyl parathion L(-1), respectively (p<0.01). The results obtained in the present study demonstrate that the EpREmt-GFP HTC cell line can be an interesting model for further development for the study of the cellular response to aquatic pollutants as well as a new tool for environmental monitoring at the molecular level.
Topics: Animals; Cell Line, Tumor; Copper; Ecotoxicology; Gene Expression Profiling; Gene Expression Regulation; Genes, Reporter; Green Fluorescent Proteins; Methyl Parathion; Mice; Rats; Reproducibility of Results; Toxicity Tests; Transgenes; Water Pollutants, Chemical
PubMed: 18533248
DOI: 10.1016/j.marenvres.2008.02.075 -
Zhejiang Da Xue Xue Bao. Yi Xue Ban =... Jun 2021To investigate the effects of maternal exposure to 13 chemicals mixture (CM) during pregnancy on pregnancy outcome and health status of maternal/offspring mice. C57BL/6...
To investigate the effects of maternal exposure to 13 chemicals mixture (CM) during pregnancy on pregnancy outcome and health status of maternal/offspring mice. C57BL/6 pregnant mice were given drinking water containing carbaryl dimethoate glyphosate methomyl methyl parathion triadimefon aspartame sodium benzoate calcium disodium ethylene diamine tetra-acetate ethylparaben butylparaben bisphenol A and acacia gum The effects of CM exposure on pregnancy outcome, health status of dams/offspring, levels of circulating inflammatory cytokines in dams/offspring and emotional related behaviors of offspring were evaluated. CM exposure during pregnancy had no significant effect on pregnancy outcome, liver function, body weight of the dams in late pregnancy and uterine/ovarian weight after delivery, however, it led to an increase in maternal serum IFN-γ level (<0.05). CM exposure during pregnancy had no significant effect on the liver function of offspring, but increased the serum IFN-γ, prefrontal cortex IFN-γ, and TNF-α and hippocampus IFN-γ levels in the offspring(all <0.01). In addition, the offspring of CM group showed significant abnormal emotion-related (autism-like) behaviors in adulthood, especially in male offspring. Low dose CM exposure during pregnancy may induce inflammation status in dams/offspring, and lead to autism-like behaviors in offspring, indicating the potential effects of low dose CM exposure on human maternal and infant health.
Topics: Adult; Animals; Autistic Disorder; Female; Humans; Male; Maternal Exposure; Mice; Mice, Inbred C57BL; Phenotype; Pregnancy; Prenatal Exposure Delayed Effects
PubMed: 34402257
DOI: 10.3724/zdxbyxb-2021-0182 -
Frontiers in Microbiology 2018Microbial degradation plays an essential role in the removal of hydrophobic organic compounds (HOCs) dispersed in soil and sediment, and its performance is greatly...
Microbial degradation plays an essential role in the removal of hydrophobic organic compounds (HOCs) dispersed in soil and sediment, and its performance is greatly affected by mineral particles which regulate HOCs bioavailability by interfacial adsorption. Likewise, bacteria cells attach to the surfaces of mineral particles as well but how bacterial attachment affects biodegradation is largely unknown. Here we report inhibitory effects of goethite and humic acid (HA)-goethite complex addition on microbial degradation of methyl parathion (MP). Using attenuated total reflectance-Fourier transform infrared spectroscopy, we observed that the adhesion of bacterial cells responsible for MP degradation on goethite occurred and the adhesive strength increased over time. We then replaced goethite with phosphate-adsorbed goethite to weaken the goethite-bacteria association and the inhibition of MP biodegradation was alleviated. These results suggested the formation of goethite-bacteria association hinder MP biodegradation. Meanwhile, our results showed that HA coating prevented bacterial attachment on goethite particles along with a drastically increased MP adsorption by goethite. The combined effect would lead to decreased mass fluxes of MP to bacterial cells and could represent another mechanism responsible for the decreased degradation rate observed in the current study.
PubMed: 30123196
DOI: 10.3389/fmicb.2018.01748 -
Biochemical Pharmacology Oct 2008Organophosphorus (OP) insecticides elicit toxicity via acetylcholinesterase inhibition, allowing acetylcholine accumulation and excessive stimulation of cholinergic...
Organophosphorus (OP) insecticides elicit toxicity via acetylcholinesterase inhibition, allowing acetylcholine accumulation and excessive stimulation of cholinergic receptors. Some OP insecticides bind to additional macromolecules including butyrylcholinesterase and cholinergic receptors. While neurotoxicity from OP anticholinesterases has been extensively studied, effects on cardiac function have received less attention. We compared the in vitro sensitivity of acetylcholinesterase, butyrylcholinesterase and [(3)H]oxotremorine-M binding to muscarinic receptors in the cortex and heart of adult (3 months) and aging (18 months) rats to chlorpyrifos, methyl parathion and their active metabolites chlorpyrifos oxon and methyl paraoxon. Using selective inhibitors, the great majority of cholinesterase in brain was defined as acetylcholinesterase, while butyrylcholinesterase was the major cholinesterase in heart, regardless of age. In the heart, butyrylcholinesterase was markedly more sensitive than acetylcholinesterase to inhibition by chlorpyrifos oxon, and butyrylcholinesterase in tissues from aging rats was more sensitive than enzyme from adults, possibly due to differences in A-esterase mediated detoxification. Relatively similar differences were noted in brain. In contrast, acetylcholinesterase was more sensitive than butyrylcholinesterase to methyl paraoxon in both heart and brain, but no age-related differences were noted. Both oxons displaced [(3)H]oxotremorine-M binding in heart and brain of both age groups in a concentration-dependent manner. Chlorpyrifos had no effect but methyl parathion was a potent displacer of binding in heart and brain of both age groups. Such OP and age-related differences in interactions with cholinergic macromolecules may be important because of potential for environmental exposures to insecticides as well as the use of anticholinesterases in age-related neurological disorders.
Topics: Acetylcholinesterase; Aging; Animals; Butyrylcholinesterase; Cerebral Cortex; Cholinesterase Inhibitors; Heart; Male; Myocardium; Organophosphorus Compounds; Oxotremorine; Rats; Rats, Sprague-Dawley; Tritium
PubMed: 18761328
DOI: 10.1016/j.bcp.2008.08.001 -
Nanoscale Advances Dec 2019This study reports the synthesis of zirconia nanoparticles loaded on various carbon substrates, namely, reduced graphene oxide (Zr-r-GO), carbon nanotubes (Zr-CNT), and...
This study reports the synthesis of zirconia nanoparticles loaded on various carbon substrates, namely, reduced graphene oxide (Zr-r-GO), carbon nanotubes (Zr-CNT), and activated carbon (Zr-AC). In addition, a composite of zirconia-iron mixed oxide loaded on activated carbon (FeZr-AC) was also synthesized. The materials were characterized using SEM-EDX, HRTEM, FTIR, Raman spectroscopy, TGA and XRD. The FeZr-AC sample was found to have a nanorod like morphology. The samples were evaluated for their sensing potential towards methyl parathion (MP) using differential pulse voltammetry in a range of 0.0 V to -0.9 V ( Ag/AgCl) by drop casting on a glassy carbon electrode (GCE). All the modified GCEs best operated at a working potential of 0.4-0.9 V Ag/AgCl/Cl. FeZr-AC was found have the best limit of detection followed by Zr-AC, Zr-CNT and Zr-r-GO with their detection limits being 1.7 × 10 M, 17.2 ×10 M, 243.3 × 10 M and 534.0 × 10 M respectively. These materials were then used to detect MP in spiked sewage samples and showed good recoveries.
PubMed: 36133142
DOI: 10.1039/c9na00589g -
Ecotoxicology and Environmental Safety Oct 2022Urinary para-nitrophenol (PNP), an exposure biomarker of ethyl parathion (EP) and methyl parathion (MP) pesticides, was still pervasively detected in the general...
BACKGROUND
Urinary para-nitrophenol (PNP), an exposure biomarker of ethyl parathion (EP) and methyl parathion (MP) pesticides, was still pervasively detected in the general population even after global restriction for years. And the concern whether there is an association of PNP level with child development of the nervous system is increasing. The current study aimed to evaluate the maternal urinary PNP concentrations during late pregnancy and the associations of PNP levels with cognitive and motor function of their children at the age of 2 years.
METHODS
323 mother-child pairs from the Sheyang Mini Birth Cohort Study were included in the current study. Gas chromatography-tandem mass spectrometry was used to measure concentrations of PNP, the specific metabolite of EP and MP, in maternal urine samples during pregnancy. Developmental quotients (DQs) scores measured with Gesell Developmental Scales were employed to evaluate cognitive and motor function of children aged 2 years. Generalized linear models were performed to analyze the associations of PNP concentrations in pregnant women's urine samples with cognitive and motor function of their children.
RESULTS
Maternal PNP was detected in all urine samples with a median of 4.11 μg/L and a range from 0.57 μg/L to 109.13 μg/L, respectively. Maternal urinary PNP concentrations showed a negative trend with DQ of motor area [regression coefficient (β) = - 1.35; 95 % confidence interval (95 %CI): - 2.37, - 0.33; P < 0.01], and the children whose mothers were in the fourth quartile exposure group performed significantly worse compared to the reference group (β = - 1.11; 95 %CI: - 1.80, - 0.42; P < 0.01). As for average DQ score, children with their mothers' urinary PNP concentrations in the third quartile group had higher scores than those in the first quartile group (β = 0.39; 95 %CI: 0.03, 0.75; P = 0.04). In sex-stratified analyses, a negative trend between maternal urinary PNP concentrations and DQ scores in motor area of children was only observed in boys (β = - 1.62; 95 %CI: - 2.80, - 0.43; P < 0.01). Boys in the third quartile group had higher DQ average scores than those in the lowest quartile as reference (β = 0.53; 95 %CI: 0.02, 1.04; P = 0.04).
CONCLUSIONS
The mothers from SMBCS may be widely exposed to EP and/or MP, which were associated with the cognitive and motor function of their children aged 2 years in a sex-specific manner. Our results might provide epidemiology evidence on the potential effects of prenatal exposure to EP and/or MP on children's cognitive and motor function.
Topics: Biomarkers; China; Cognition; Cohort Studies; Female; Gas Chromatography-Mass Spectrometry; Humans; Male; Methyl Parathion; Nitrophenols; Pesticides; Pregnancy; Pregnant Women
PubMed: 36075123
DOI: 10.1016/j.ecoenv.2022.114051 -
Environmental Health Perspectives Aug 2007In this investigation we documented the pesticide urinary metabolite levels of farmworker children in North Carolina, determined the number of different metabolites...
BACKGROUND
In this investigation we documented the pesticide urinary metabolite levels of farmworker children in North Carolina, determined the number of different metabolites detected for each child, and delineated risk factors associated with the number of metabolites.
METHODS
Urine samples were collected from 60 Latino farmworker children 1-6 years of age (34 female, 26 male). Interviews were completed by their mothers in Spanish. We analyzed urine samples for 14 pesticide metabolites, including the organophosphate pesticides chlorpyrifos, coumaphos, diazinon, isazaphos, malathion, pirimiphos, and parathion and its methyl counterpart; a common metabolite of at least 18 pyrethroid insecticides; the repellent DEET; and the herbicides 2,4,5-trichlorphenoxyacetic acid, 2,4-dichlorophenoxyacetic acid, acetochlor, atrazine, and metolachlor. Predictors included measures of paraoccupational, residential, and environmental exposure, child characteristics, and mother characteristics.
RESULTS
Thirteen metabolites were present in the urine samples. Organophosphate pesticide metabolites were detected in a substantial proportion of children, particularly metabolites of parathion/methyl parathion (90.0%; geometric mean 1.00 microg/L), chlorpyrifos/chlorpyrifos methyl (83.3%; geometric mean 1.92 microg/L), and diazinon (55.0%; geometric mean 10.56 microg/L). The number of metabolites detected ranged from 0 to 7, with a mode of 4 detected (28.3%). Boys, children living in rented housing, and children with mothers working part-time had more metabolites detected.
CONCLUSIONS
Children in farmworker homes experience multiple sources of pesticide exposure. Pesticides may remain in their environments for long periods. Environmental and occupational health changes are needed to address these exposures. Research is needed with more precise measures of exposure and on the health effects of concurrent exposure to multiple pesticides.
Topics: Agriculture; Child; Child, Preschool; Environmental Monitoring; Environmental Pollutants; Female; Herbicides; Housing; Humans; Infant; Insect Repellents; Insecticides; Male; North Carolina; Organophosphorus Compounds
PubMed: 17687456
DOI: 10.1289/ehp.9975