Search results for "Contamination"
showing 10 items of 916 documents
An innovative method for the detection of contaminant viral genome in cell cultures
2012
The use of cell cultures involves different fields of biology, from diagnosis to research. Moreover, technologies based on animal cells represent a useful tool to the development of biological products for the prophylaxis and therapy in humans and animals. Therefore, it is necessary to perform quality controls, including virological tests. Several tests performed in research laboratories are able to discriminate one or more viral species, but it is not possible to demonstrate the presence of contaminant viral genome with one non-specific method. The aim of this work consisted on the realization of a biomolecular method able to detect and to identify by sequencing extraneous viral genome in …
Development of a performance threshold approach for identifying the management options for stabilisation/solidification of lead polluted soils
2014
Two soils spiked with lead at different rates were stabilised/solidified using Portland cement and fy ash at different soil:binder ratios, and tested for their setting time, unconfined compressive strength, leachability and durability. A performance threshold approach was used in order to identify optimal management options for the products of the S/S treatment. Results show that soil texture, percentage of binders and lead concentration play an important part in the treatment, significantly influencing the performance of the resulting products in terms of curing, compressive strength and durability. Pb soil concentrations higher than 15000 mg kg-1 were found to heavily reduce the applicab…
Mechanism of action of sphingolipids and their metabolites in the toxicity of fumonisin B1.
2005
Fumonisins are a group of mycotoxins produced primarily by Fusarium moniliforme. Several fumonisins have been isolated through out the years but only fumonisin B1, B2 and B3 are the ones present in naturally contaminated foods, with B1 being the most toxic between them. The structural similarity between sphinganine and fumonisin B1 suggests that the mechanism of action of this mycotoxin is mainly via disruption of sphingolipid metabolism, this is an important step in the cascade of events leading to altered cell growth, differentiation and cell injury. Sphingolipids are a second type of lipid found in cell membranes, particularly nerve cells and brain tissues. Toxicity of fumonisin B1 is gi…
Deoxynivalenol contamination in cereal-based foodstuffs from Spain: Systematic review and meta-analysis approach for exposure assessment
2022
Abstract The presence of deoxynivalenol (DON) has been repeatedly detected in cereal-based products collected from Spanish markets over the last years. Hence, the aim of this study was to conduct a systematic review and meta-analysis of the concentration and prevalence of DON in cereals and cereal-based products from Spanish markets intended for human consumption, in order to integrate the available data. Then, an exposure assessment was performed based on national consumption data. Results revealed a strong impact of DON in breakfast cereals (pooled concentration = 105.34 ng/g; pooled prevalence = 58%) and bread and derived products (pooled concentration = 95.17 ng/g; pooled prevalence = 6…
Methods of in vitro toxicology
2002
In vitro methods are common and widely used for screening and ranking chemicals, and have also been taken into account sporadically for risk assessment purposes in the case of food additives. However, the range of food-associated compounds amenable to in vitro toxicology is considered much broader, comprising not only natural ingredients, including those from food preparation, but also compounds formed endogenously after exposure, permissible/authorised chemicals including additives, residues, supplements, chemicals from processing and packaging and contaminants. A major promise of in vitro systems is to obtain mechanism-derived information that is considered pivotal for adequate risk asses…
A critical analysis of the cold plasma induced lipid oxidation in foods
2018
Abstract Background Cold plasma is an emerging, economical and environment-friendly technology with potential applications in food and bioprocessing industry, including microbial decontamination, enzyme inactivation, shelf-life extension, and physicochemical modification. These advantages stem from the cocktail of reactive species and the physical processes that are associated with gaseous electrical discharges. However, when oxygen is present as a component of the gas in which plasma discharges are made, the reactive oxygen species (ROS) could result in decreased food quality. The lipids oxidation induced by an oxygen-containing cold plasma process can eventually affect the acceptability a…
Green Analytical Chemistry
2008
We discuss the origins and the fundamentals of Green Analytical Chemistry (GAC), based on the literature published about clean, environmentally-friendly or GAC methods. We pay special attention to the strategies and the tools available to make sample-pretreatment and analytical methods greener. We consider that the main principles are to replace toxic reagents, to miniaturize and to automate methods, making it possible to reduce dramatically the amounts of reagents consumed and wastes generated, so reducing or avoiding side effects of analytical methods. We also consider on-line decontamination or passivation of wastes to be of special interest in making analytical chemistry sustainable.
A vacuum cell for obtaining clean surfaces on liquid low melting point metals
1997
Abstract Clean oxide film-free surface of liquid gallium was obtained in a sealed vacuum cell with a glass lid for observation. The cell was evacuated to high vacuum (10 -4 Pa) before admission of liquid and sealing. The surface contamination was about 2–5% of the free area and did not exhibit noticeable increase during several months of storing and employing the cell. The cell described allows observation of surface flows, capillary phenomena and crystallization processes under different conditions.
Determination of Platinum-Group Elements (PGE) from catalytic converters in soil by means of docimasy and INAA.
1996
The nickelsulfide fire assay (docimasy) for the enrichment of platinum-group elements (PGEs) has been modified for the use with small samples and combined with instrumental neutron-activation analysis (INAA). This procedure has been applied to the determination of PGEs exhausted from catalytic converters and deposited in soil near the Wiesbadener Kreuz (highway A3, Frankfurt-Koln). Our results show a considerable enhancement of the Pt (up to 330 ng/g), Pd (6.6 ng/g) and Rh (7.5 ng/g) contents close to the highway.
Use of semipermeable membrane devices for assessment of air quality in Tangier (Morocco)
2009
Semipermeable membrane devices (SPMDs) have been used for the evaluation of the contamination of air in both the urban and the industrial area in Tangier (Morocco). Benzene, toluene, ethylbenzene a...