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31.
Giuseppa Di Bella Asma Ben Tekaya Asma Beltifa Hedi Ben Mansour Emanuele Sajia 《Journal of environmental science and health. Part. B》2019,54(5):345-356
Contaminants belonging to various classes, as polychlorobiphenyls, polycyclic aromatic hydrocarbons, organochlorine pesticides, organophosphorous pesticides, pyrethroid insecticides, fungicides, herbicides, synergists, carbamates, acaricides and insect growth regulators were simultaneously analysed by GC-MS/MS in 118 Italian and Tunisian culinary herbs and spices. The results obtained in Italian samples shown that laurel samples were the most contaminated with the presence of 15 residues on 140, whereas in rosemary (max value of 35?ng/g for cis-chlorfenyvinphos) and oregano (max value of 118.16?ng/g for ethion) some occasional residues can be observed, but always lower than the maximum residue levels; all the others samples shown no contamination. Among Tunisian samples, only rosemary contains a notably high content of pollutants exceeded the EU maximum residue limits (i.e., alachlor and phosalone with level of 359.2 and 43.3?ng/g, respectively), while oregano was determined to be free of contaminant residues. Considering the comparison among the different organic pollutants in Italian and Tunisian spices and herbs evaluated and the differences observed in this study a harmonization of regulation on contaminant residues in herbs and spices for human consumption should be needed, considering their increased use in diet and cooking. 相似文献
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Daniele Di Trapani Gaetano Di Bella Gaspare Viviani 《Waste management (New York, N.Y.)》2013,33(10):2108-2115
Sanitary landfills for Municipal Solid Waste (MSW) disposal have been identified as one of the most important anthropogenic sources of methane (CH4) emissions; in order to minimize its negative effects on the environment, landfill gas (LFG) recovery is a suitable tool to control CH4 emissions from a landfill site; further, the measurement of CH4 emissions can represent a good way to evaluate the effectiveness of LFG recovering systems. In general, LFG will escape through any faults in the landfill capping or in the LFG collection system. Indeed, some areas of the capping can be more permeable than others (e.g. portions of a side slope), especially when considering a temporarily capped zone (covered area that is not expected to receive any further waste for a period of at least 3 months, but for engineering reasons does not have a permanent cap yet). These areas, which are characterized by abnormal emissions, are usually defined as “features”: in particular, a feature is a small, discrete area or an installation where CH4 emissions significantly differ from the surrounding zones. In the present study, the influence that specific features have on CH4 emissions has been investigated, based on direct measurements carried out in different seasons by means of a flux chamber to the case study of Palermo (IT) landfill (Bellolampo). The results showed that the flux chamber method is reliable and easy to perform, and the contoured flux maps, obtained by processing the measured data were found to be a suitable tool for identifying areas with abnormal (high) emissions. Further, it was found that a relationship between methane emission rates and landfill side slope can be established. Concerning the influence of the temporary HDPE cover system on CH4 recovery efficiency, it contributed to a significant decrease of the free surface area available for uncontrolled emissions; this aspect, coupled to the increase of the CH4 volumes collected by the LFG recovery system, led to a significant increase of the recovery efficiency. 相似文献
33.
Speciation of inorganic arsenic in alimentary and environmental aqueous samples by using derivative anodic stripping chronopotentiometry (dASCP) 总被引:2,自引:0,他引:2
The purpose of this research was to develop a sensitive and accurate chronopotentiometric method at a gold film electrode, to determine trace and ultra trace levels of As(III) and As(V) in alimentary and environmental water systems. As(III) was directly determined in the aqueous matrix at a deposition potential of -300 mV for 180 s and at a constant anodic current of 2.5 microA, without any sample pre-treatment; moreover the chronopotentiometric method did not require a time-consuming de-oxygenation step prior to the analysis. A 3M HCl solution was chosen as the best stripping medium. The direct analysis of As(V) required the application of a high negative over-potential and, thus, measurements were characterized by poor reproducibility; therefore As(V) was determined after reduction to As(III) with KI in a strong hydrochloric acid solution. Under the optimised electrochemical conditions, detection limits of 0.08 microg As(III) l(-1) were achieved and no significant interferences from Cd, Cu, Pb, Zn and organic substances were observed. As(V) was the most abundant species in all the studied environmental and alimentary aqueous matrices. Amongst the beverages, tea and coffee presented the As(V) highest concentration ranges (934-1740 microg l(-1) and 850-1290 microg l(-1), respectively) while bottled mineral water the lowest (<1.61 microg l(-1)); whereas As(III) levels lower than 5.0 microg l(-1) were detected only in wine samples. 相似文献
34.
Organophosphorus and organochlorine pesticides, phosphorated plasticizers, chloroparaffins and phthalate esters contamination in bergamot essential oils produced in Calabria in the crop years 1999-2000 was studied by HRGC in connection with detectors FPD, ECD, MS. Residues of dicofol and tetradifon were found in oils from both crop years. The mean dicofol concentration was 0.26 mg/l in samples from 1999 and 0.20 mg/l in those from 2000; the mean tetradifon content was 0.06 mg/l for both the crop years. Among plasticizers, residues of diisobutyl phthalate, di-n-butyl phthalate, and bis(2-ethylhexyl) phthalate were found in samples from crop years 1999 and 2000, the mean content were 1.22 and 1.23 mg/l, 1.51 and 1.65 mg/l, 1.38 and 1.42 mg/l respectively. 相似文献
35.
Micrographs of retinas from the deep-sea fish Cataetyx laticeps revealed visual cells containing membranous whorls in the ellipsoids of the inner segments resulting from stretching and
modifications of the mitochondria membranes and their cristae. These pathological structures seem to be homologous to the
whorls observed in retinas of human carriers of Tay-Sachs disease. This disease, a genetic disorder, is found in humans and
some mammals. Our findings in fish suggest that the gene responsible can be found throughout the vertebrate evolutionary tree,
possibly dormant in most taxa.
Received: 20 April 2000 / Accepted in revised form: 16 June 2000 相似文献
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