Search results for "Diazinon"
showing 10 items of 29 documents
American cockroach control assays in the municipal sewerage system of Valencia (Spain)
2013
ABSTRACT Several insecticides (including different active substances and formulations) were applied to sewer shafts to control Periplaneta americana (LINNAEUS, 1758) populations in Valencia (eastern Spain). Results show that the best products for cockroach control were the paints (with and without insecticide), which provided an optimal reduction of P. americana populations for up to three months (P < 0.001). Therefore, it is important to note that the reduction of cockroach populations as well as the persistence of the insecticide effect in sewers was similar in both types of paints. A product combining two pyrethroids (Tetramethrin and Alfacipermetrin) and piperonyl butoxide also gave …
Evaluation of working air quality by using semipermeable membrane devices
2008
Abstract It has been evaluated the use of semipermeable membrane devices (SPMDs) as passive samplers of organophosphorus pesticides from air, in order to determine the contamination of working environments. Additionally, the use of SPMDs as portable samplers has been also considered. The analytical methodology for the determination of diazinon, chlorpyrifos-methyl, pirimiphos-methyl, chlorpyrifos and fenthion in SPMDs exposed to contaminated air was based on microwave-assisted extraction and gas chromatography with mass spectrometry determination. Limit of detection (LOD) values from 2 to 4 ng SPMD−1 and repeatability from 2 to 7% were obtained by using the aforementioned methodology. Theor…
Matrix effects on solid-phase microextraction of organophosphorus pesticides from water
1997
Abstract This study develops a method for solid-phase microextraction (SPME) of eight organophosphorus pesticides, diazinon, fenthion, fenitrothion (sumithion), methyl-parathion, parathion, methyl-trithion, ethion and triazophos, from water. Determination is carried out by gas chromatography with nitrogen-phosphorus detection. To perform the SPME, poly(dimethylsiloxane) and polyacrylate fibers were initially compared on the basis of their absorption capacities for the selected pesticides, and polyacrylate was selected to accomplish the rest of assays. The main factors affecting the SPME process such as memory effect, stirring rate, extraction temperature and absorption-time profile were stu…
Selective solid-phase extraction of organophosphorus pesticides and their oxon-derivatives from water samples using molecularly imprinted polymer fol…
2020
Abstract A molecularly imprinted polymer was synthesized and characterized to be used as solid-phase extraction sorbent for simultaneous chlorpyrifos and diazinon and their oxon derivatives. Several imprinted polymers were prepared and evaluated in a retention study of these analytes compared with a non-printed polymer. Several parameters affecting the extraction of imprinted polymer such as washing solvent, composition and volume of the eluting solvent and sample volume, were also investigated. Under the optimum conditions, the developed method provided satisfactory limits of detection ranging between 0.07 µg L−1 to 0.12 µg L−1 and the material showed an excellent reusability (> 50 reuses)…
Pesticides in the Ebro River basin: Occurrence and risk assessment
2016
In this study, 50 pesticides were analyzed in the Ebro River basin in 2010 and 2011 to assess their impact in water, sediment and biota. A special emphasis was placed on the potential effects of both, individual pesticides and their mixtures, in three trophic levels (algae, daphnia and fish) using Risk Quotients (RQs) and Toxic Units (TUs) for water and sediments. Chlorpyrifos, diazinon and carbendazim were the most frequent in water (95, 95 and 70% of the samples, respectively). Imazalil (409.73 ng/L) and diuron (150 ng/L) were at the highest concentrations. Sediment and biota were less contaminated. Chlorpyrifos, diazinon and diclofenthion were the most frequent in sediments (82, 45 and 2…
Effect of Sublethal Concentrations of Pesticides on the Feeding Behavior of Daphnia magna
1994
Daphnia magna was exposed to sublethal levels (1/4, 1/2, and 2/3 LC50 and LC50) of endosulfan and diazinon to determine the effect of these pesticides on filtration and ingestion rates. The experiments were performed with the unicellular algae Nannochloris oculata in a density of 5 x 10(5) cells/ml. Prior to these experiments, the acute toxicity of both pesticides was evaluated to calculate the LC50s. The 24-hr LC50 values were 0.62 mg/liter and 0.9 microgram/liter for endosulfan and diazinon, respectively. Rates of filtration and ingestion declined with increasing toxicant concentrations after a short exposure of 5 hr. The effective concentration at which feeding rates were reduced to 50% …
Efficient Nucleophilic Degradation of an Organophosphorus Pesticide “Diazinon” Mediated by Green Solvents and Microwave Heating
2019
An efficient strategy for the degradation of organophosphate pesticide Diazinon was investigated. In this work, ionic liquids, bio-based solvents, and two conventional organic solvents were used as reaction media. Kinetics studies by means of half-life (t1/2,h) were followed by 31P NMR and the products analyzed by GC-MS, HPLC-MS and NMR techniques. These results have shown that t1/2 values in ionic liquids were the lowest and also they were able to activate two electrophilic centers in Diazinon, whilst degradation in bio-based solvents occurred slowly by only an aromatic pathway. In addition, a study to estimate the influence of green activation techniques was carried out by using Ultrasoun…
Occurrence and removal efficiency of pesticides in sewage treatment plants of four Mediterranean River Basins.
2013
Removal of contaminants in the sewage treatment plants (STPs) can be incomplete causing their release to the environment. In this paper, the results of an extensive survey on more than 40 pesticides carried out in 2010 and 2011 in 16 STPs of Ebro, Guadalquivir, Jucar and Llobregat Rivers (Spain) are presented. In 2010, of 43 analytes screened, 29 were detected in influent and 28 in effluent samples, meanwhile in 2011, of 50 analytes, 33 and 34 were detected, respectively. Pesticides were in the range of 0.33 ng L(-1) (terbumeton, 2011)-2526.05 ng L(-1) (diuron, 2010) for influent and 0.25 ng L(-1) (terbumeton, 2011)-2821.12 ng L(-1) (carbendazim, 2011) for effluent. Regarding the sludge sam…
An approach to the diazinon toxicity in the European eel: bioaccumulation studies
1993
Abstract The acute toxicity effects of diazinon on European eel ( Anguilla anguilla ) were examined using short-term exposures in static conditions. In these conditions the 96-h median lethal concentration (LC 50 ) was 0.086 mg/1. In addition, the eels were exposed to two sublethal diazinon concentrations, 0.042 and 0.056 mg/1 (1/2 and 2/3 LC 50 96-h, respectively) for different exposure times, till a maximum of 96 h, and bioaccumulation and clearance of this insecticide in liver, muscle, gill and blood tissues were studied. BCF values of diazinon after 96 h exposure to 0.042 mg/l were 1850 in liver, 875 in gill and 775 in eel muscle. BCF values of diazinon over a 48-h exposure period to 0.…