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Organohalogen contaminants and trace metals in North-East Atlantic porbeagle shark (Lamna nasus)
2014
Bendall, Victoria A. | Barber, Jonathan L. | Papachlimitzou, Alexandra | Bolam, Thi | Warford, Lee | Hetherington, Stuart J. | Silva, Joana F. | McCully, Sophy R. | Losada, Sara | Maes, Thomas | Ellis, Jim | Law, Robin J.
The North-East Atlantic porbeagle (Lamna nasus) population has declined dramatically over the last few decades and is currently classified as ‘Critically Endangered’. As long-lived, apex predators, they may be vulnerable to bioaccumulation of contaminants. In this study organohalogen compounds and trace elements were analysed in 12 specimens caught as incidental bycatch in commercial gillnet fisheries in the Celtic Sea in 2011. Levels of organohalogen contaminants were low or undetectable (summed CB and BDE concentrations 0.04–0.85mgkg−1wet weight). A notably high Cd concentration (7.2mgkg−1wet weight) was observed in one mature male, whereas the range observed in the other samples was much lower (0.04–0.26mgkg−1wet weight). Hg and Pb concentrations were detected only in single animals, at 0.34 and 0.08mgkg−1wet weight, respectively. These contaminant levels were low in comparison to other published studies for shark species.
اظهر المزيد [+] اقل [-]Dioxin formation and control in a gasification–melting plant
2015
Kawamoto, Katsuya | Miyata, Haruo
We investigated dioxin formation and removal in a commercial thermal waste treatment plant employing a gasification and melting process that has become widespread in the last decade in Japan. The aim was to clarify the possibility of dioxin formation in a process operation at high temperatures and the applicability of catalytic decomposition of dioxins. Also, the possible use of dioxin surrogate compounds for plant monitoring was further evaluated. The main test parameter was the influence of changes in the amount and type of municipal solid waste (MSW) supplied to the thermal waste treatment plant which from day to day operation is a relevant parameter also from commercial perspective. Here especially, the plastic content on dioxin release was assessed. The following conclusions were reached: (1) disturbance of combustion by adding plastic waste above the capability of the system resulted in a considerable increase in dioxin content of the flue gas at the inlet of the bag house and (2) bag filter equipment incorporating a catalytic filter effectively reduced the gaseous dioxin content below the standard of 0.1 ng toxic equivalency (TEQ)/m³ N, by decomposition and partly adsorption, as was revealed by total dioxin mass balance and an increased levels in the fly ash. Also, the possible use of organohalogen compounds as dioxin surrogate compounds for plant monitoring was further evaluated. The levels of these surrogates did not exceed values corresponding to 0.1 ng TEQ/m³ N dioxins established from former tests. This further substantiated that surrogate measurement therefore can well reflect dioxin levels.
اظهر المزيد [+] اقل [-]Organochlorine residues in brook trout from remote lakes in the northeastern United States
1983
Haines, T.A. (University of Maine at Orono, Orono, Me. (USA). Zoology Dept.)
The relevance of physicochemical and biological parameters for setting emission limit values for plants treating complex industrial wastewaters
2014
Huybrechts, Diane | Weltens, Reinhilde | Jacobs, Griet | Borburgh, Ab | Smets, Toon | Hoebeke, Lut | Polders, Caroline
The influents of plants treating complex industrial wastewaters from third parties may contain a large variety of often unknown or unidentified potentially harmful substances. The conventional approach of assessing and regulating the effluents of these plants is to set emission limit values for a limited set of physicochemical parameters, such as heavy metals, biological oxygen demand, chemical oxygen demand and adsorbable organic halogen compounds. The objective of this study was to evaluate the relevance of physicochemical parameters for setting emission limit values for such plants based on a comparison of effluent analyses by physicochemical and biological assessment tools. The results show that physicochemical parameters alone are not sufficient to evaluate the effectiveness of the water treatment plants for removing hazardous compounds and to protect the environment. The introduction of toxicity limits and limits for the total bioaccumulation potential should be considered to supplement generic parameters such as chemical oxygen demand and adsorbable organic halogens. A recommendation is made to include toxicity screening as a technique to consider in the determination of best available techniques (BAT) during the upcoming revision of the BAT reference document for the waste treatment industries to provide a more rational basis in decisions on additional treatment steps.
اظهر المزيد [+] اقل [-]Direct aqueous derivation and gas chromatographic analysis of halogenated lower carboxylates in environmental samples
1997
Ozawa, H. (Nagano-ken. Research Inst. for Health and Pollution (Japan))
Analytical method for hydrophilic polar environmental pollutants was studied. Among these pollutants, the halogenated lower carboxylates were the target compounds of this investigation. A novel but simple derivatization method necessary for sample preparation for instrumental analysis was developed. The new derivatization method for the carboxylates is not a conventional chemical reaction in non-aqueous solvent following isolation from the environmental samples but rather, a direct aqueous reaction ; direct conversion of the carboxylates to amides using a carbodiimide in dilute aqueous solution. Halogenoanilines were selectively used with dicyclohexylcarbodiimide (DCC) under acidic conditions at room temperature to form the anilide derivatives. Moreover, this reaction proceeds while mixing the sample water, DCC, a halogenoaniline, and small volume of extracting solvent. Thus, for the first time, simultaneous derivatization of the carboxylates and extraction of the products into solvent was achieved. Based on the results, simple and practical determination methods by gas chromatography were developed for traces of these carboxylates in environmental samples and the proposed methods were applied to some real samples. Such analytical derivatization methods for carboxylates are useful and noteworthy because they can form C-N bonds in aqueous media under mild conditions with carbodiimides and N atoms of amino and other compounds.
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