1,721,022 research outputs found
Recent applications of liquid chromatography-mass spectrometry to residue analysis of antimicrobials in food of animal origin
No full textResidual antimicrobials in food constitute a risk to human health. Although epidemiological data on the real magnitude of their adverse effects are very scarce, they indicate that food could be an important vehicle for evolution and dissemination of antimicrobial-resistant bacteria. Public health agencies in many countries rely on detection by mass spectrometry (MS) for unambiguous identification of residues of antimicrobial agents in animal food products for human consumption. The introduction of relatively inexpensive and robust liquid chromatography (LC)–MS systems has given a strong impulse to the development of confirmatory methods for the above medicines in foodstuffs. The initial part of this review, after a brief introduction into the field of antimicrobials, is dedicated to the most important EU regulations and directives for control of residues of these substances in animal products. The main attention in this review is on the sample-treatment and MS detection systems in use today for analysing the most important classes of antimicrobials in various biological matrices (milk, animal tissues, eggs, and honey). As evidenced by this review, reversed-phase LC combined with tandem MS, usually triple-quadrupole MS (QqQMS), is currently the preferred technique in most residue analysis of a single-class of antimicrobials. A recently emerging analytical strategy is that of developing methods for detecting a large variety of veterinary drugs belonging to different classes, including pesticides (multi-class residue analysis). To do this, simple and generic extraction and separation techniques applicable to a broad range of compounds differing in physical and chemical properties have been adopted. Such methods are still based mainly on LC–QqQMS. Emerging alternative MS detection systems are time-of-flight MS, which provides accurate mass of the analyte(s), or Q–linear ion trap (IT) MS that eliminates some limitations of ITMS n
Extraction procedures
No full textFood Toxicants Analysis covers different aspects from the field of analytical food toxicology including emerging analytical techniques and applications to detect food allergens, genetically modified organisms, and novel ingredients (including those of functional foods). Focus will be on natural toxins in food plants and animals, cancer modulating substances, microbial toxins in foods (algal, fungal, and bacterial) and all groups of contaminants (i.e., pesticides), persistent organic pollutants, metals, packaging materials, hormones and animal drug residues. The first section describes the current status of the regulatory framework, including the key principles of the EU food law, food safety, and the main mechanisms of enforcement. The second section addresses validation and quality assurance in food toxicants analysis and comprises a general discussion on the use of risk analysis in establishing priorities, the selection and quality control of available analytical techniques. The third section addresses new issues in food toxicant analysis including food allergens and genetically modified organisms (GMOs). The fourth section covers the analysis of organic food toxicants
Fungicide and herbicide residues in water
No full textHandbook of Water Analysis, Second Edition provides current analytical techniques for detecting compounds in water samples. Maintaining the detailed and accessible style of the original, this edition demonstrates water sampling and preservation methods by enumerating different ways to measure chemical and radiological characteristics and giving step-by-step descriptions of separation, residue determination, and clean-up techniques for a variety of fresh- and salt-water. It reveals new information regarding the analysis of endocrine disrupting compounds and residues of plastics and contains four new chapters on acrylamide, trihalomethanes, phthalates, and volatile organic compounds in water
Occurrence and abundance of dicarboxylated metabolites of nonylphenol polyethoxylate surfactants in treated sewages
No full textMatrix solid-phase dispersion as a valuable tool for extracting contaminants from foodstuffs
No full textThis review updates our knowledge on matrix solid-phase dispersion (MSPD), a sample treatment procedure that is increasingly used for extracting/purifying contaminants from a variety of solid, semi-solid, viscous, and liquid foodstuffs. MSPD is primarily used because of its flexibility, selectivity, and the possibility of performing extraction and cleanup in one step, this resulting in drastically shortening of the analysis time and low consumption of toxic and expensive solvents. Technical developments and parameters influencing the extraction yield and selectivity are examined and discussed. Experimental results for the analysis of pesticides, veterinary drugs, persistent en v iron mental chemicals, naturally occurring toxicants, and surfactants in food are reviewed
Metodi chimici per la rivelazione delle cianotossine.
No full textCyanobacteria are a ubiquitous group of photosynthetic procariota. Especially in eutrophic inland surface waters,
they attain high densities and may form blooms and scums. Several cyanobacterial species produce, as secondary
metabolites, cyanotoxins which can threat human health. On the basis of their toxicological properties they are
grouped into: hepatotoxins, neurotoxins, cytotoxins, toxins with irritating potential, also acting on the gastrointestinal
system. Humans may be exposed to cyanotoxins via the oral route, which is by far the most important, as a
consequence of ingesting contaminated drinking water, food, some dietary supplements or water during recreational
activities. High levels of cyanotoxins in drinking and bathing waters have been associated with acute and short-term
toxic effects in humans. Some concern is raised also with respect to the chronic exposure to low cyanotoxin levels,
whose effects remain a critical issue to be clarified. This report summarizes the ecological, chemical, methodological,
toxicological and epidemiological information available on this issue, identifies the actual risky exposure scenarios,
and, when possible, provides reference values
Environmental contaminants
No full textDairy foods account for a large portion of the Western diet, but due to the potential diversity of their sources, this food group often poses a challenge for food scientists and their research efforts. Bringing together the foremost minds in dairy research, Handbook of Dairy Foods Analysis compiles the top dairy analysis techniques and methodologies from around the world into one, well-organized volume
Method development for trace determination of poly(naphtalenesulfonate)-type pollutants in water by liquid cromatography-electrospray mass spectrometry
No full textA very sensitive analytical procedure based on LC-MS for determining trace amounts of the more relevant poly(naphthalenesulfonate) (PNS) contaminants present in environmental waters is presented. Extraction was performed on a styrene-divinylbenzene copolymer resin solid-phase extraction cartridge after addition of ammonium acetate to the sample. Small amounts of ammonium acetate in the mobile phase allowed the determination and characterisation of the four shorter oligomers by liquid chromatography-electrospray mass spectrometry, Under such conditions the electrospray process generates fully ionised molecules which greatly simplifies interpretation of spectra and quantitation. Additionally, confirmatory ions can be generated by the in-source collision-induced decomposition process. The effectiveness of the method was assessed in recovery experiments from drinking and river water samples spiked with commercial mixtures of PNS concrete plasticizers also referred as naphthalenesulfonate-formaldehyde condensates. Moreover, the performance of this method was compared to methods using ion-pair chromatography coupled with fluorimetric and mass spectrometric detection. Method detection limits were in the low picomolar range (1 ng/l for the monomer) for each isomer. In order to evaluate the environmental relevance of PNS type compounds waste, river and ground water grab samples were analysed. Concentrations of PNS oligomers detected in these samples ranged between 53 ng/l and 32 mug/l
Liquid chromatographic determination of linear alkylbenzenesulfonates in aqueous environmental samples
No full textNo abstract provided
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