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Journal of Microencapsulation 1987Comparative studies of the vaporization rate of the volatile components present in aqueous suspensions of microcapsules containing the organophosphorous insecticides...
Comparative studies of the vaporization rate of the volatile components present in aqueous suspensions of microcapsules containing the organophosphorous insecticides S-1,2-bis (ethoxycarbonyl) ethyl-O,O-dimethyl phosphorodithioate (malathion) and O,O-diethyl S-2-ethylthioethyl phosphorodithioate (disulfoton) from inert, porous surfaces, under controlled laboratory conditions simulating natural environmental factors, were carried out. Volatilization into the atmosphere, under the given experimental conditions, was evaluated by the rate of weight loss of the microcapsule deposit and by gas chromatographic analysis of the residual insecticide on the support.
Topics: Capsules; Disulfoton; Insecticides; Malathion; Suspensions; Volatilization
PubMed: 3504503
DOI: 10.3109/02652048709021803 -
Journal of Economic Entomology Oct 1972
Topics: Animals; Carbamates; Carbofuran; Disulfoton; Insect Vectors; Insecticides; Metamorphosis, Biological; Plant Diseases; Time Factors; Zea mays
PubMed: 5085777
DOI: 10.1093/jee/65.5.1236 -
The Journal of Dairy Research May 2016This Research Communication reports analysis of 37 compounds comprising polycyclic aromatic hydrocarbons (PAHs), organochlorine and organophosphate pesticides (OCPS and...
This Research Communication reports analysis of 37 compounds comprising polycyclic aromatic hydrocarbons (PAHs), organochlorine and organophosphate pesticides (OCPS and OPPS) in milk powder (one brand each of commercial infant formulae, follow-on formulae and baby formulae purchased from a local supermarket in Romania). The selected analytes were investigated using gas chromatography-mass spectrometry (GC-MS), gas chromatography with electron capture detector (GC-ECD) and gas chromatography with thermionic sensitive detection (GC-TSD). The estimated limits of detection for most target analytes were in the μg/kg level (range 0·001-0·320 µg/kg). The purpose of the study was to determine the selected analytes, to assess the exposure of babies and infants and to produce data for comparison with tolerable limits according to the European Union Regulations. In most of the samples the organochlorine pesticides values were under the limit of detection. Exceptions were heptachlor epoxide and endosulfan sulphate, the last of which was found in all analysed samples at low concentrations. We also found detectable levels of ethoprophos, parathion-methyl, chlorpyrifos, prothiofos, guthion, disulfoton and fenchlorphos in most of the analysed samples. Benzo[a]pyrene, which is used as an indicator for the presence of PAHs, was not detected in selected samples. The low level of exposure to contaminants indicates that there are no health risks for the infants and babies that consume this brand of milk powder formulae.
Topics: Animals; Food Contamination; Food, Preserved; Gas Chromatography-Mass Spectrometry; Humans; Hydrocarbons, Chlorinated; Infant; Infant Formula; Infant, Newborn; Maximum Allowable Concentration; Milk; Organophosphates; Pesticides; Polycyclic Aromatic Hydrocarbons; Romania
PubMed: 27210498
DOI: 10.1017/S0022029916000169 -
Journal of Toxicology. Clinical... Aug 1982The cytochrome P-450-dependent monooxygenase system catalyzes a wide variety of oxidations of pesticide chemicals and related compounds. These reactions include...
The cytochrome P-450-dependent monooxygenase system catalyzes a wide variety of oxidations of pesticide chemicals and related compounds. These reactions include epoxidation and aromatic hydroxylation, aliphatic hydroxylation, O-, N- and S-dealkylation, N-oxidation, oxidative deamination, S-oxidation, P-oxidation, desulfuration and ester cleavage and may result in either detoxication or activation of the pesticide. The current status of such reactions, relative to the production, in vivo, of biologically active intermediates in pesticide metabolism is summarized. More recently we have shown that the FAD-containing monooxygenase of mammalian liver (E.C.1.14.13.8), a xenobiotic metabolizing enzyme of broad specificity formerly known as an amine oxidase, is involved in a variety of pesticide oxidations. These include sulfoxidation of organophosphorus insecticides such as phorate and disulfoton, oxidative desulfuration of phosphonate insecticides such as fonofos and oxidation at the phosphorus atom in such compounds as the cotton defoliant, folex. The relative importance of the FAD-containing monooxygenase vis-a-vis the cytochrome P-450-dependent monooxygenase system is discussed, based on in vitro studies on purified enzymes.
Topics: Animals; Carbamates; Cytochrome P-450 Enzyme System; Flavin-Adenine Dinucleotide; Insecticides; Organophosphorus Compounds; Oxidation-Reduction; Oxygenases; Pesticides; Phosphorus; Substrate Specificity; Sulfoxides
PubMed: 7161848
DOI: 10.3109/15563658208990394 -
Macromolecular Rapid Communications Jun 2018The threat of chemical warfare agents (CWA) compels research into novel self-decontaminating materials (SDM) for the continued safety of first-responders, civilians, and...
The threat of chemical warfare agents (CWA) compels research into novel self-decontaminating materials (SDM) for the continued safety of first-responders, civilians, and active service personnel. The capacity to actively detoxify, as opposed to merely sequester, offending agents under typical environmental conditions defines the added value of SDMs in comparison to traditional adsorptive materials. Porous polymers, synthesized via the high internal phase emulsion (HIPE) templating, provide a facile fabrication method for materials with permeable open cellular structures that may serve in air filtration applications. PolyHIPEs comprising polydicyclopentadiene (polyDCPD) networks form stable hydroperoxide species following activation in air under ambient conditions. The hydroperoxide-containing polyDCPD materials react quickly with CWA simulants, Demeton-S and 2-chloroethyl ethyl sulfide, forming oxidation products as confirmed via gas chromatography mass spectrometry. The simplicity of the detoxification chemistry paired with the porous foam form factor presents an exciting opportunity for the development of self-decontaminating filter media.
Topics: Chemical Warfare Agents; Chromatography, Liquid; Decontamination; Disulfoton; Emulsions; Hydrogen Peroxide; Indenes; Mass Spectrometry; Mustard Gas; Oxidation-Reduction; Polymers; Porosity; Styrenes; Time Factors
PubMed: 29786164
DOI: 10.1002/marc.201800194 -
Journal of Economic Entomology Oct 1972
Topics: Animals; Carbofuran; Dimethoate; Disulfoton; Female; Insecta; Insecticides; Ovum; Phorate; Plant Diseases; Trees
PubMed: 5085816
DOI: 10.1093/jee/65.5.1484 -
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 -
Food Chemistry Aug 2017The dissipation/degradation of the pesticides dimethoate, terbufos, disulfoton, and pirimiphos-methyl were evaluated in milled toasted maize and wheat flour (gofio)...
The dissipation/degradation of the pesticides dimethoate, terbufos, disulfoton, and pirimiphos-methyl were evaluated in milled toasted maize and wheat flour (gofio) during three months of storage. Their dissipation kinetics and residual levels were determined, as well as their possible decomposition into some of their main transformation products (disulfoton sulfoxide, terbufos sulfone and disulfoton sulfone). For this purpose, pesticide-free milled toasted maize and wheat samples were spiked with the pesticides, and they were then stored in the darkness at ambient temperature in a closed container to simulate current storage conditions of such packed food. A multiresidue analysis based on the QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) method was performed for the simultaneous determination of these pesticides and their metabolites. After three months of storage, the dissipation of residues ranged between 34% (pirimiphos-methyl) and 86% (disulfoton) for maize gofio and between 69% (terbufos) and 92% (disulfoton and pirimiphos-methyl) for wheat gofio. The results demonstrated that the degradation was slower in gofio than in wheat gofio and that none of the selected metabolites were detected in any of the samples. Dissipation curves of all studied pesticides fitted to a first-order decay curve in both types of cereals.
Topics: Chromatography, Gas; Edible Grain; Flour; Food Storage; Kinetics; Organophosphorus Compounds; Pesticide Residues; Pesticides; Triticum; Zea mays
PubMed: 28372254
DOI: 10.1016/j.foodchem.2017.02.148 -
Analytical and Bioanalytical Chemistry Jul 2012In the present study, a new analytical method has been developed for the simultaneous quantification of 15 organophosphorus pesticides, including some of their...
In the present study, a new analytical method has been developed for the simultaneous quantification of 15 organophosphorus pesticides, including some of their metabolites, (disulfoton-sulfoxide, ethoprophos, cadusafos, dimethoate, terbufos, disulfoton, chlorpyrifos-methyl, malaoxon, fenitrothion, pirimiphos-methyl, malathion, chlorpyrifos, terbufos-sulfone, disulfoton-sulfone and fensulfothion) in three different types of commercial cereal-based baby foods. Dispersive solid-phase extraction (dSPE) with multi-walled carbon nanotubes (MWCNTs) was used together with gas chromatography with nitrogen phosphorus detection. Most favorable conditions involved a previous ultrasound-assisted extraction of the sample with acetonitrile containing formic acid. After evaporation of the extract and redissolution in water, a dSPE procedure was carried out with MWCNTs. The whole method was validated in terms of repeatability, linearity, precision and accuracy and matrix effect was also evaluated. Absolute recoveries were in the range 64-105 % with relative standard deviation values below 7.6 %. Limits of quantification achieved ranged from 0.31 to 5.50 μg/kg, which were lower than the European Union maximum residue limits for pesticide residues in cereal-based baby foods.
Topics: Chromatography, Gas; Edible Grain; European Union; Food Contamination; Infant Food; Nanotubes, Carbon; Pesticide Residues; Solid Phase Extraction
PubMed: 22623047
DOI: 10.1007/s00216-012-6103-7