PCB analysis

N. Kannan, D. E. Schulz-Bull, G. Petiick and J. C. Duinker, High-resolution PCB analysis of Kanecliloi, Phenocloi and Sovol mixtures using multidimensional gas cliro-matography , Int. J. Environ. Anal. Chem. 47 201 -215 (1992). 

Not all of these isomers are completely separated by the conditions given here, but all arc readily detected by plotting the masses of the molecular ions. Pesticides can interfere with polychlorinated biphenyl (PCB) analysis. 

PCB analysis using immunosensors based on magnetic beads and carbon screen-printed electrodes in marine sediment and soil samples... 

Unhomogenized, homogenized, and collocated soil samples collected for waste oil, other heavy petroleum fuels, or PCB analysis... 

Example 3.1 Samples of bulk remediation waste for PCB analysis... 

Highly selective to halogenated and oxygenated compounds Electron capture detector EDB, DBCP (EPA 8011) Acrylamide (EPA 8032) Phenols (EPA 8041) Phthalates (EPA 8061) Organochlorine pesticides (EPA 8081) PCBs (EPA 8082) Nitroaromatics and cyclic ketones (EPA 8091) Haloethers (EPA 8111) Chlorinated herbicides (EPA 8151) CLP SOW for organic analysis Interferences from Elemental sulfur (S8) Waxes, lipids, other high molecular weight compounds Phthalate esters, which are common laboratory contaminants Oil in PCB analysis... 

PCBs Analysis of hexane extract of water sample [37,99, 100]... 

The causal relationship between the occurrence of non-ortho CBs and other dioxin-like compounds and reproductive impairment in Forster s tern was firmly established in 1989 by US Great Lakes researchers, [154, 155]. An improvement in reproductive performance of the same population between 1983 and 1988 was recorded [156]. This was due to low river flow and consequent reduction in contamination input to the Lake ecosystem. TEQs derived from congener-specific PCB analysis showed 42% reduction in chemical toxicity. Subsequent studies in Green Bay, Wisconsin, USA by USEPA established uptake rates for specific CB congeners in Forster s tern chicks. For example, 70 ng/day, 200 ng/day, 6.5 ng/day, and 0.14 ng/day for CB-77, CB-105, CB-126, and CB-169 respectively and 270 pg/day for TEQs [157]. Determination of PCDD/Fs and PCBs in California peregrine falcons and their eggs indicated that CB-126 was largely responsible for the TEQs derived. The other CBs of importance were CB-126[Pg.146]

Mullin MD (1985) Congener-specific PCB analysis. EPA Large Lakes Research Station, Gross IL, p 38... 

Mullin MD, Pochini CM, McCrindle S, Romkes M, Safe SH, Safe LM (1984) High-resolution PCB analysis synthesis and chromatographic properties of all 209 PCB congeners. Environ SciTecnnol 18 468-476... 

PCB retention times increase with chlorination level, and within chlorination levels, with less chlorine substitution in the ortho position (i.e., coplanar PCBs are more strongly retained). These relationships are of theoretical interest but are of less use now that accurate retention time assignments are possible with actual standards. The use of commercial mixtures such as Aroclors as quantitative secondary standards for CQCS PCB analysis is now to be discouraged [4], as detailed studies of congener distributions show significantly different proportions among different lots [7]. In the case of Aroclor 1254, there are actually two different mixtures of radically different composition produced by totally different synthetic processes [9]. 

A final refinement of congener-specific PCB analysis arises from the fact that 19 of the congeners actually exist as stable enantiomeric pairs, either component of which can withstand racemization even at the elevated temperatures required to elute them from a capillary GC separation [6]. Some congeners containing either a 236- or 2346-chlorine-substituted ring and three or more chlorines in the ortho position exist in two mirror-image forms by virtue of their inability to rotate around the bond between the two rings. These so-called atropisomers do not contain asymmetric carbon... 

G. M. Frame, Congener-specific PCB analysis. Anal. Chem. (59 468A (1997). 

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