Polychlorodibenzo-£-dioxins determination

This technique has been used for the determination of polychlorobiphenyls, polychlorodibenzo-p-dioxins, polychlorodibenzofurans, alkyl phosphates, chlorinated insecticides, organophosphorus insecticides, triazine herbicides. Dacthal insecticide, insecticide/herbicide mixtures, mixtures of organic compounds and organotin compounds in soils, and polyaromatic compounds, polychlorobiphenyls, chlorinated insecticides and organotin compounds in non-saline sediments and anionic surfactants in sludges. 

Von Bavel et al. [55] used a solid phase carbon trap in conjunction with supercritical fluid chromatography for the simultaneous determination of polychlorobiphenyls, pesticides, polychlorodibenzo-p-dioxins and polychlorodibenzofurans in soils. 

A good example of the application of gas chromatography-mass spectrometry to the determination of polychlorodibenzo-p-dioxin and dibenzofurans up to the octochlorocogeners in soils and sediments is that of Smith et al. [110] which, it is claimed, is sufficiently sensitive to determine down to 1-5 parts per trillion of these substances. 

Representative multiple ion mass chromatograms of soil samples are presented in Fig. 5.4. These gas chromatography-mass spectrometric determinations of polychlorodibenzo-p-dioxin and polychlorodibenzofurans, and non-ortho polychlorobiphenyls in differing types of samples serve to exemplify the versatility of the procedure for such analyses. The gas chromatography-mass spectrometric data were usually uncluttered by extraneous components, and interpretation of the data was routinely straightforward. 

Von Bavel et al. [55] have developed a solid phase carbon trap (PX-21 active carbon) for the simultaneous determination of polychlorodibenzo-p-dioxins and polychlorodibenzofurans also polychlorobiphenyls and chlorinated insecticides in soils using superfluid extraction liquid chromatography for the final determination. Supercritical fluid extraction with carbon dioxide has been applied to the determination of dioxins in soil [114],... 

Various workers have discussed methodology for the determination of polychlorodibenzo-p-dioxins and dibenzofurans in sediments [110, 111, 115] and silts [109]. The method described by Smith et al. [110] for the determination of polychlorodibenzo-p-dioxins and dibenzofurans in soils and discussed in section 5.7.1.1 is also applicable to sediments. Taguchi [112] presented preliminary results obtained in a round robin inter-... 

Namiesnik et al. [33] have reviewed the analysis of soils and sediments for organic contaminants. They discuss methods of sample preparation and isolation-preconcentration prior to instrumental determination. Compound classes discussed include volatile organic compounds, polychlorobiphenyls, polyaromatic compounds, pesticides and polychlorodibenzo-p-dioxins and polychlorodibenzofurans. 

Miellet [80] and Lopez-Avila et al. [81] have reviewed the applications of Soxhlet extraction to the determination of pesticides in soil. This technique has been applied extensively to the extraction of polycyclic aromatic hydrocarbons, volatile organic compounds, pesticides, herbicides and polychlorodibenzo-p-dioxins in soils. Details of the extraction procedures and the analytical finish employed are reviewed in Table 1.1. 

Hass JR, Friesen MD, Parker CE, et al. 1977. Use of negative-ion chemical ionization mass spectrometry in the determination of polychlorodibenzo-p-dioxins at the part-per-trillion level in tissue samples. Environ Health Perspect 20 246. 

Lawn RE. 1988. Some aspects of the determination of polychlorodibenzo-p-dioxins and polychloro-dibenzofurans in environmental and biological samples. Anal Proc 25 49-50. 

Liberti A, Ciccioli P, Brancaleoni E, et al. 1982. Determination of polychlorodibenzo-p-dioxins and polychlorodibenzofiirans in environmental samples by gas chromatography-mass spectrometry. J Chromatogr 242 111-118. 

Buser HR, Bosshardt HP (1976), J. Assoc. Off. Anal. Chem. 59 562-569.. .Determination of polychlorodibenzo-p-dioxins and -dibenzofurans in commercial pentachlorophenols by combined gas chromatography-mass spectrometry"... 

Polychlorodibenzo-p-dioxins (PCDDs) and polychlorodibenzofurans (PCDFs) are two classes of compounds that are of environmental concern because of the high toxicity of those isomers with 2,3,7,8-tetrachloro-substitution [12]. The PCDDs/PCDFs are monitored in air, rain, effluents, soil, and biota matrices. Usually, the total concentration of all PCDD/PCDF congener groups (i.e., total tetra-chlorinated dioxins, total pentachlorinated dioxins, etc.) and the concentrations of each of the seventeen 2,3,7,8-substituted toxic isomers are monitored. Such determinations require extensive sample preparation, sixteen expensive C 12-2,3,7,8-substituted internal standards [13], and mass spectrometers of high capital cost. High-resolution MS [14,15] or triple-stage quadrupole MS (TSQMS) [16-18] is necessary in order to differentiate between (1) PCDDs/PCDFs and interferences, such as polychlorinated biphenyls [19], and (2) Ci2-PCDFs and native PCDDs. 

Organic compounds sought include naturally derived materials, such as mycotoxins and off-flavours (produced by rancidification or spoilage), and man-made/industrial chemicals, e.g. pesticides, veterinary drugs, environmental contaminants (such as polychlorodibenzo-p-dioxins, polychlorinated biphenyls, polynuclear aromatic hydrocarbons, etc.) and food tainting compounds (e.g. 2,4,6-trichloro-anisole, the compound responsible for musty cork taint in wine, arising from the inappropriate use of wood preservatives). GC-MS and HPLC-API-MS are widely used for these types of analyses. Desirable food components present at trace levels, such as nutrients, are also determined using these techniques. 

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