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International Journal of Environmental... Dec 2022Organophosphates (OPPs) are an important element of modern agriculture; however, because they are being used excessively, their residues are leaching and accumulating in...
Organophosphates (OPPs) are an important element of modern agriculture; however, because they are being used excessively, their residues are leaching and accumulating in the soil and groundwater, contaminating aquatic and terrestrial food chains. An important OPP called disulfoton is frequently used to eradicate pests from a wide range of crops, including Brazil's coffee crops. Additionally, it does not easily degrade in the environment, and as such, this compound can slowly build up in living organisms such as humans. Moreover, this compound has been classified as "extremely hazardous" by the World Health Organization. This study evaluated the degradation efficiency of disulfoton using a Fenton-like reaction catalyzed by magnetite nanoparticles and determined the toxicity of the by-products of the degradation process using the bioindicator . Further, the removal efficiency of disulfoton was determined to be 94% under optimal conditions. On the other hand, the bioassay showed different toxic, cytotoxic, genotoxic, and mutagenic outcomes even after the remediation process. In conclusion, the Fenton process catalyzed by magnetite nanoparticles presents great efficiency for the oxidation of disulfoton. However, it is important to highlight that the high degradation efficiency of the Fenton-based process was not sufficient to achieve detoxification of the samples.
Topics: Humans; Disulfoton; Oxidation-Reduction; Agriculture; Soil; Crops, Agricultural
PubMed: 36613108
DOI: 10.3390/ijerph20010786 -
Se Pu = Chinese Journal of... Feb 2022Disulfoton, an organophosphorus pesticide, is used to control cotton, beet, potato, and other seedling period aphids, leaf moths, underground pests, etc., with internal...
[Determination of disulfoton and its metabolites in agricultural products by dispersive soild phase extraction-ultra high performance liquid chromatography-tandem mass spectrometry].
Disulfoton, an organophosphorus pesticide, is used to control cotton, beet, potato, and other seedling period aphids, leaf moths, underground pests, etc., with internal absorption, killing, gastric poisoning, and fumigation. Disulfoton is a highly toxic organophosphate pesticide, which can inhibit cholinesterase activity, resulting in neurophysiological disorders by inhalation, feeding, and transdermal absorption. Disulfoton is difficult to degrade in the environment, which leads to enrichment in organisms and interference with endocrine. This compound is harmful to the ecological environment and human health. To ensure the quality and safety of food, it is important to develop a detection method for disulfoton and its metabolites in agricultural products. A reliable method based on dispersive solid phase extraction (d-SPE) with ultra high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) was developed for the determination of disulfoton and its metabolites (disulfoton sulfone, disulfoton sulfoxide, demeton-, demeton- sulfone, and demeton- sulfoxide) in agricultural products (pea, asparagus, wheat, coffee bean, and peanut). The optimal extraction method was as follows: 5.0 g the samples were extracted with acetonitrile (wheat, coffee bean, and peanut presoaked in 5 mL water) in a 50 mL centrifuge tube, followed by 10 min vortex. Before 30 s vortex, 4 g NaCl was added. After 5 min centrifugation, 1.5 mL of the supernatant was cleaned up with 50 mg octadecylsilane bonded silica (C), 50 mg primary secondary amine (PSA), and 50 mg aminopropyl (NH) adsorbents. The analytes were separated on a Thermo Syncronis C column (150 mm×2.1 mm, 5 μm) with gradient elution using water and acetonitrile at a column temperature of 40 ℃. The injection volume was 2 μL. Disulfoton and its metabolites were analyzed in multiple reaction monitoring (MRM) mode with positive electrospray ionization (ESI) for the selective quantification. Qualitative and quantitative analyses were accorded to the retention times and characteristic ion pairs with one parent ion and two fragment ions. Quantitative analysis was performed by an external standard method using matrix-matched calibration curves. All the parameters that affected the extraction efficiencies were optimized. C, PSA, and NH gave good recoveries of 87.9%-109.0%. Other adsorbents, multiwalled carbon nanotubes (MWCNTs), hydroxylated multiwalled carbon nanotubes (OH-MWCNTs), carboxylated multiwalled carbon nanotubes (COOH-MWCNTs), octylsilane bonded silica (C), strong cation exchange (SCX) and neutral alumina (-AlO), led to recoveries below 56.2%. The combination of adsorbents was also considered. Seven different combinations of 50 mg C, 50 mg PSA, and 50 mg NH were chosen for the optimization experiments. There were no obvious differences in these combinations, and the target analytes recoveries ranged from 81.0% to 109.3% with relative standard deviations (RSDs) between 0.6% and 12.5%. The matrix effect could affect the extraction efficiency. The adsorbents of 50 mg C, 50 mg PSA, and 50 mg NH showed weaker matrix effects as compared with other combinations of adsorbents in the instrument. The results for the matrix effect showed that peanuts and asparagus exceeded 20%, requiring matrix-matched calibration curves. Under the optimized conditions, disulfoton and its metabolites showed good linearities (≥0.9981) in the range of 2.0-200.0 μg/L. The average spiked recoveries of disulfoton and its metabolites in peas, asparagus, wheat, peanuts, and coffee beans ranged from 75.0% to 110.0%, with RSDs of 0.7% to 14.9%. The limits of detection (LODs) were between 0.02 and 2.0 μg/kg, and the limits of quantification (LOQs) were 5.0 μg/kg. The method was applied for the detection of 80 commercial productions, and neither disulfoton nor its metabolites were found. The proposed method is rapid, accurate, highly selective, and sensitive, and it is suitable for the simultaneous determination of disulfoton and its metabolites in grain, oil crops, vegetables, and other matrices.
Topics: Chromatography, High Pressure Liquid; Disulfoton; Humans; Nanotubes, Carbon; Organophosphorus Compounds; Pesticides; Solid Phase Extraction; Tandem Mass Spectrometry
PubMed: 35080159
DOI: 10.3724/SP.J.1123.2021.04028 -
Environmental Health Perspectives Apr 2017Growing evidence suggests that pesticide use may contribute to respiratory symptoms.
BACKGROUND
Growing evidence suggests that pesticide use may contribute to respiratory symptoms.
OBJECTIVE
We evaluated the association of currently used pesticides with allergic and non-allergic wheeze among male farmers.
METHODS
Using the 2005-2010 interview data of the Agricultural Health Study, a prospective study of farmers in North Carolina and Iowa, we evaluated the association between allergic and non-allergic wheeze and self-reported use of 78 specific pesticides, reported by ≥ 1% of the 22,134 men interviewed. We used polytomous regression models adjusted for age, BMI, state, smoking, and current asthma, as well as for days applying pesticides and days driving diesel tractors. We defined allergic wheeze as reporting both wheeze and doctor-diagnosed hay fever ( = 1,310, 6%) and non-allergic wheeze as reporting wheeze but not hay fever ( = 3,939, 18%); men without wheeze were the referent.
RESULTS
In models evaluating current use of specific pesticides, 19 pesticides were significantly associated ( < 0.05) with allergic wheeze (18 positive, 1 negative) and 21 pesticides with non-allergic wheeze (19 positive, 2 negative); 11 pesticides were associated with both. Seven pesticides (herbicides: 2,4-D and simazine; insecticides: carbaryl, dimethoate, disulfoton, and zeta-cypermethrin; and fungicide pyraclostrobin) had significantly different associations for allergic and non-allergic wheeze. In exposure-response models with up to five exposure categories, we saw evidence of an exposure-response relationship for several pesticides including the commonly used herbicides 2,4-D and glyphosate, the insecticides permethrin and carbaryl, and the rodenticide warfarin.
CONCLUSIONS
These results for farmers implicate several pesticides that are commonly used in agricultural and residential settings with adverse respiratory effects.
Topics: Adult; Agricultural Workers' Diseases; Agriculture; Farmers; Humans; Iowa; Male; North Carolina; Occupational Exposure; Pesticides; Prospective Studies; Respiratory Sounds
PubMed: 27384423
DOI: 10.1289/EHP315 -
PloS One 2019Senescence Marker Protein (SMP30) is a metalloenzyme that shows lactonase activity in the ascorbic acid (AA) biosynthesis pathway in non-primate mammals such as a mouse....
Senescence Marker Protein (SMP30) is a metalloenzyme that shows lactonase activity in the ascorbic acid (AA) biosynthesis pathway in non-primate mammals such as a mouse. However, AA biosynthesis does not occur in the primates including humans. Several studies have shown the role of SMP30 in maintaining calcium homeostasis in mammals. In addition, it is also reported to have promiscuous enzyme activity with an organophosphate (OP) substrate. Hence, this study aims to recombinantly express and purify the SMP30 proteins from both mouse and human, and to study their structural alterations and functional deviations in the presence of different divalent metals. For this, mouse SMP30 (MoSMP30) as well as human SMP30 (HuSMP30) were cloned in the bacterial expression vector. Proteins were overexpressed and purified from soluble fractions as well as from inclusion bodies as these proteins were expressed largely in insoluble fractions. The purified proteins were used to study the folding conformations in the presence of different divalent cations (Ca2+, Co2+, Mg2+, and Zn2+) with the help of circular dichroism (CD) spectroscopy. It was observed that both MoSMP30 and HuSMP30 acquired native folding conformations. To study the metal-binding affinity, dissociation constant (Kd values) were calculated from UV-VIS titration curve, which showed the highest affinity of MoSMP30 with Zn2+. However, HuSMP30 showed the highest affinity with Ca2+, suggesting the importance of HuSMP30 in maintaining calcium homeostasis. Enzyme kinetics were performed with γ-Thiobutyrolactone and Demeton-S in the presence of different divalent cations. Interestingly, both the proteins showed lactonase activity in the presence of Ca2+. In addition, MoSMP30 and HuSMP30 also showed lactonase activity in the presence of Co2+ and Zn2+ respectively. Moreover, both the proteins showed OP hydrolase activities in the presence of Ca2+ as well as Zn2+, suggesting the metal-dependent promiscuous nature of SMP30.
Topics: 4-Butyrolactone; Animals; Binding Sites; Calcium-Binding Proteins; Cations, Divalent; Disulfoton; Humans; Intracellular Signaling Peptides and Proteins; Kinetics; Mice; Mice, Inbred BALB C; Molecular Dynamics Simulation; Protein Binding; Sequence Homology, Amino Acid
PubMed: 31220150
DOI: 10.1371/journal.pone.0218629 -
Royal Society Open Science Jul 2018This study was performed to determine the storage stability of organophosphorus pesticide residues in high oil content commodity matrices, peanut and soya bean. The...
This study was performed to determine the storage stability of organophosphorus pesticide residues in high oil content commodity matrices, peanut and soya bean. The storage conditions included different types of solvents (ethyl acetate, acetone and hexane) and corresponding extracted matrix solutions, light and temperature. It was found that three pesticides degraded quickly especially in ethyl acetate solvent. They decreased greater than 30% when stored for 3 days at -20°C in ethyl acetate; the results showed that the stability could be improved in the extracted matrix solutions. Light had a slight effect for stability of phorate and fenthion, while it played an important effect for disulfoton with the exception of ethyl acetate as solvent. Even at -20°C, exposure to solvents or extracted matrix solution resulted in 40.67, 96.33 and 35.07% loss of phorate, disulfoton and fenthion. Hence, it could be assumed that these three residues could be more stable at lower temperature, in the dark and in acetone or hexane extracted peanut and soya bean solutions.
PubMed: 30109115
DOI: 10.1098/rsos.180757 -
Journal of Nematology Dec 2000The efficacy of foliar applications of oxamyl were evaluated for the management of Rotylenchulus reniformis on cotton in Mississippi. Two tests were established in...
The efficacy of foliar applications of oxamyl were evaluated for the management of Rotylenchulus reniformis on cotton in Mississippi. Two tests were established in Tallahatchie County on a fine sandy loam soil (56.8% sand, 37.8% silt, 5.3% clay, pH 5.4, and 0.3% OM) naturally infested with R. reniformis. Oxamyl was applied as a foliar spray at 0.14, 0.27, or 0.53 kg a.i./ha to cotton plants that had reached the sixth true leaf growth stage. A second oxamyl application was applied 14 days after the first treatment at the same rates. All oxamyl treatments also received aldicarb at 0.59 kg a.i./ha at planting. Controls consisted of aldicarb alone, disulfoton (which is not a nematicide), and an untreated control. Oxamyl reduced R. reniformis numbers at 79 and 107 days after planting in Test 1 and at 62 and 82 days after planting in Test 2 compared to aldicarb at 0.59 kg a.i./ha alone and the controls that received neither material. Average reniform population densities in oxamyl-treated plots were 24.5% and 30% lower than with aldicarb alone and the controls. Cotton plant height was greater in plots that received oxamyl at all rates than in the controls. Cotton in oxamyl plus aldicarb and aldicarb alone treatments produced more bolls per plant and had a greater total boll weight than disulfoton and the untreated control. Seed cotton yields were greater in oxamyl-treated plots than for disulfoton-treated and the untreated control.
PubMed: 19271008
DOI: No ID Found -
Scandinavian Journal of Work,... 1985After passing toxicity and experimental therapeutic tests, four oxime cholinesterase reactivators [PAM (pyridine aldoxime methiodide), PAC (pralidoxime, pyridine... (Clinical Trial)
Clinical Trial Comparative Study
After passing toxicity and experimental therapeutic tests, four oxime cholinesterase reactivators [PAM (pyridine aldoxime methiodide), PAC (pralidoxime, pyridine aldoxime methylchloride), TMB4 (trimedoxime), and DMO4 (obidoxime, Toxogonin, LüH6)] were compared in clinical trials. All of them proved capable of restoring erythrocyte cholinesterase activity and relieving symptoms and signs of organophosphate insecticide poisoning. Mildly and moderately poisoned patients can be treated by several injections of any one of these drugs alone, but severe cases need the synergistic action of atropine, as well as treatments for two to three consecutive days. Although response to treatment is stronger with TMB4 and DMO4, they are not recommended for routine treatment because of their dangerous adverse side effects.
Topics: Alanine Transaminase; Cholinesterase Reactivators; Cholinesterases; Clinical Trials as Topic; Disulfoton; Erythrocytes; Humans; Insecticides; Obidoxime Chloride; Occupational Diseases; Parathion; Pralidoxime Compounds; Trimedoxime
PubMed: 3914075
DOI: No ID Found -
Plant Disease Jan 1997Eight cotton cultivars, with and without aldicarb treatment, were evaluated for their effect on the severity of the root-knot nematode-Fusarium wilt disease complex in...
Eight cotton cultivars, with and without aldicarb treatment, were evaluated for their effect on the severity of the root-knot nematode-Fusarium wilt disease complex in cotton. A randomized complete block design with a split-plot arrangement of treatments was used with cotton cultivars as the main plots and nematicide treatments as the subplots. Results in 1994 and 1995 were similar. Yield of lint, boll weight, and wilt and root-gall ratings were different among cultivars and between nematicide treatments both years. Increased lint yield and boll weight, and reduced root-gall and wilt ratings were associated with application of aldicarb. Increased lint percentage was associated with application of aldicarb in 1994, but not in 1995. Fiber micronaire, elongation, uniformity, and strength were different among cultivars, but not between nematicide treatments. Fiber length (UHM; Upper-Half Mean) was different among cultivars and was higher in the aldicarb-treated plots in both years. Numbers of Meloidogyne incognita second stage juveniles and eggs extracted from soil samples were lower in the aldicarb-treated plots in July, but not at harvest, both years. Population densities of M. incognita were not different among cultivars, except the mid-season sample in 1995.
PubMed: 30870950
DOI: 10.1094/PDIS.1997.81.1.66 -
Journal of Nematology Dec 2003Alternatives to reduce or modify nematicide use for minimizing groundwater contamination in Easter lily were explored in two field trials. Alternatives to standard...
Alternatives to reduce or modify nematicide use for minimizing groundwater contamination in Easter lily were explored in two field trials. Alternatives to standard 1,3-dichloropropene (1,3-D) plus phorate injection in the first trial were: (i) delaying applications until after winter rains, (ii) removing roots from planting stock, (iii) 1,3-D via drip irrigation, (iv) a chitin-urea soil amendment, (v) the registered insecticide disulfoton, and (vi) several nonregistered nematicides. None of the treatments equaled the standard treatment. In the second trial, potential benefits of adding a systemic nematicide, oxamyl (OX), or a fungicide, metalaxyl (MX), to the standard treatment were explored. Preplant drip irrigation applications of metam sodium (MS), sodium tetrathiocarbonate (ST), and emulsifiable 1,3-D were evaluated alone and in combination with postplant applications of OX and MX. Several drip-applied treatments performed comparably to the standard treatment with respect to the most important criteria of crop quality, bulb circumference. Metam-sodium in combination with either or both OX and MX, 1,3-D plus OX and MX, and ST plus OX and MX provided the best results.
PubMed: 19262778
DOI: No ID Found