Search results for "residue"
showing 10 items of 390 documents
Glyphosate-based herbicides are toxic and endocrine disruptors in human cell lines.
2009
International audience; Glyphosate-based herbicides are the most widely used across the world; they are commercialized in different formulations. Their residues are frequent pollutants in the environment. In addition, these herbicides are spread on most eaten transgenic plants, modified to tolerate high levels of these compounds in their cells. Up to 400 ppm of their residues are accepted in some feed. We exposed human liver HepG2 cells, a well-known model to study xenobiotic toxicity, to four different formulations and to glyphosate, which is usually tested alone in chronic in vivo regulatory studies. We measured cytotoxicity with three assays (Alamar Blue (R), MTT ToxiLight (R)), plus gen…
Orientation theory in arithmetic geometry
2016
This work is devoted to study orientation theory in arithmetic geometric within the motivic homotopy theory of Morel and Voevodsky. The main tool is a formulation of the absolute purity property for an \emph{arithmetic cohomology theory}, either represented by a cartesian section of the stable homotopy category or satisfying suitable axioms. We give many examples, formulate conjectures and prove a useful property of analytical invariance. Within this axiomatic, we thoroughly develop the theory of characteristic and fundamental classes, Gysin and residue morphisms. This is used to prove Riemann-Roch formulas, in Grothendieck style for arbitrary natural transformations of cohomologies, and a …
Solid phase techniques in the extraction of pesticides and related compounds from foods and soils
1994
The application of SPE technology to the isolation of pesticides and related compounds from food and soils has grown enormously in the last decade. Much of this growth has been due to the relative ease of sample handling and the wide range of solid supports currently available for a variety of applications. The aim of this review is to present the methods for solid phase extraction (SPE) of pesticide residues from soils and foods. There are three main areas according to the type of approach used to handle the sample: solid phase extraction, solid phase clean-up (SPC), and matrix solid phase dispersion (MSPD). This review covers milk products, fatty foods, fruits, vegetables, and soils. Soli…
Analytical method for simultaneous determination of pesticide and veterinary drug residues in milk by CE-MS
2009
10 páginas, 2 figuras, 4 tablas.
SOLID-PHASE EXTRACTION OF PESTICIDES FROM WATER SAMPLES
1990
LC-MS/MS characterisation and determination of dansyl chloride derivatised glyphosate, aminomethylphosphonic acid (AMPA), and glufosinate in foods of…
2021
Abstract Glyphosate and other polar and acidic pesticides have been particularly studied due to the concerns over widespread and intensive use. The chemical properties of these compounds necessitate use of customised methods, such as derivatisation or ion exchange chromatography. These approaches present a compatibility problem with ESI-MS due to presence of salts and non-volatile compounds. For that reason, a simple procedure has been developed for the extraction, pre-column derivatisation with dansyl chloride (5-(dimethylamino)naphthalene-1-sulfonyl chloride), and mass spectrometric detection of glyphosate, AMPA, and glufosinate after the separation on a C18 stationary phase. The dansyl d…
The development and validation of a rapid method for the determination of antimicrobial agent residues in milk and meat using ultra performance liqui…
2014
Abstract A new multi-class method has been developed for the identification and quantification of the residues of 26 antibiotics from different classes (sulfonamides, macrolides, tetracyclines, penicillins, and quinolones) in milk and meat by ultra performance liquid chromatography coupled to hybrid quadrupole – high resolution Orbitrap mass spectrometry (UPLC–qOrbitrap). The sample preparation included extraction of two analytical portions with acetonitrile and 5% trichloroacetic acid, respectively, followed by centrifugation and filtration. The method was validated over three days at 50% of MRL (maximum residue limit) set in the European Union. Experiments on spiked meat and milk samples …
Pots, plants and animals: Broad-spectrum subsistence strategies in the Early Neolithic of the Moroccan Rif region
2019
Abstract The transition from hunter-gathering to food-producing societies in the Mediterranean zone of north Africa was complex and variable, likely influenced by local ecological conditions as well as the socio-economic origins of the population. The adoption of domestic plants and animals was piecemeal, with hunting and gathering continuing as an important part of local subsistence strategies. Here, we investigate the timing and extent of the adoption of agricultural practices, namely herding and cultivation, in three diverse coastal and inland Early Neolithic sites in the Mediterranean Maghreb region, namely Ifri Oudadane, Ifri n’Etsedda and Hassi Ouenzga. Results from absorbed lipid res…
Particle size distributions of currently used pesticides in ambient air of an agricultural Mediterranean area
2014
This work presents first data on the particle size distribution of 16 pesticides currently used in Mediterranean agriculture in the atmosphere. Particulate matter air samples were collected using a cascade impactor distributed into four size fractions in a rural site of Valencia Region, during July to September in 2012 and from May to. July in 2013. A total of 16 pesticides were detected, including six fungicides, seven insecticides and three herbicides. The total concentrations in the particulate phase (TSP: Total Suspended Particulate) ranged from 3.5 to 383.1 pg m(-3). Most of the pesticides (such as carbendazim, tebuconazole, chlorpyrifos-ethyl and chlorpyrifos-methyl) were accumulated …
Long‐Term Durum Wheat‐Based Cropping Systems Result in the Rapid Saturation of Soil Carbon in the Mediterranean Semi‐arid Environment
2016
Climate, soil physical–chemical characteristics, land management, and carbon (C) input from crop residues greatly affect soil organic carbon (SOC) sequestration. According to the concept of SOC saturation, the ability of SOC to increase with C input decreases as SOC increases and approaches a SOC saturation level. In a 12-year experiment, six semi-arid cropping systems characterized by different rates of C input to soil were compared for ability to sequester SOC, SOC saturation level, and the time necessary to reach the SOC saturation level. SOC stocks, soil aggregate sizes, and C inputs were measured in durum wheat monocropping with (Ws) and without (W) return of aboveground residue to the…