Consumption of fish and shellfish from contaminated areas may be an important source of human exposure to persistent organohalogen compounds such as polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs), and polychlorinated dibenzofurans (PCDFs). We determined concentrations of 2,3,7,8-substituted PCDDs and PCDFs and 19 PCB congeners in whole blood samples from three groups of men, 40-54 years of age, with different consumption levels of crabs from a fjord area in southern Norway polluted with organochlorine compounds from a magnesium production plant. A significant increase of many PCDD/PCDF congeners was found in the blood when comparing the referents, moderate-, and high-intake groups. The greatest difference was observed for several of the PCDFs that are characteristic for the contamination of the marine biota of the fjord. PCBs, in general, play a minor role in the contamination of the fjord by the magnesium production process, except for the highly chlorinated congeners such as PCB-209. Nevertheless, almost all PCBs increased from the referents to the high-intake group. However, the relative concentrations of several highly chlorinated PCBs (particularly PCB-209) in blood are unexpectedly low compared to their abundance in crabs, indicating low uptake of these congeners. The exposure to PCDDs/PCDFs from crab consumption calculated from individual body burdens of these compounds were in good agreement with the intake estimated from previously measured concentrations in crabs, reported fishing sites, and consumption. Almost all subjects in the high-intake group exceeded the tolerable weekly intake of 35 pg TEQ/kg body weight/week proposed by a Nordic Expert Group.ImagesFigure 2.Figure 3.Figure 4.Figure 5.Figure 6.

Human milk samples from 28 mothers at Oslo City Hospital, Norway, were collected in 1991 and analyzed for individual polychlorinated biphenyl (PCB) congeners, IUPAC numbers 28, 74, 99, 101, 105, 114, 118, 128, 138, 141, 153, 156, 157, 170, 180, 194, and 206, plus selected non-ortho-substituted compounds, IUPAC numbers 77, 126, and 169. Sum DDTs (sum of concentrations of DDT and related compounds), hexachlorobenzene (HCB), oxychlordane, transnonachlor, and sum hexachlorocyclohexanes (HCHs) (sum of concentrations of alpha-HCH, beta-HCH, and gamma-HCH) were also determined. The mean levels of sum DDTs, HCB, oxychlordane, transnonachlor, and sum HCHs were 338, 41, 9, 19, and 36 ng/g, respectively, in human milk fat. p,p'-DDE and beta-HCH accounted for 81 and 93% of sum DDTs and sum HCHs, respectively. The mean level of sum PCBs (sum of mean concentrations of 20 individual congeners) was 372 ng/g milk fat. A very good correlation was found between sum PCBs and PCB-153 (r = .97). Sum PCBs determined on a capillary column was found to account for 62-79% of total PCBs calculated by using the packed column method used in previous human milk surveys in Norway. Comparison with previous results revealed that the mean sum PCB, HCB and sum DDT levels were decreased by 70, 65, and 75%, respectively during the past 9 yr. The contribution of individual PCDD/PCDF (earlier Norwegian study) and non- and mono-ortho-substituted PCB congeners to the total calculated toxic equivalent values was assessed, and the PCBs were found to constitute a major part of the TCDD equivalents in human milk, with PCB-126 as the main contributor.

A method for determining non-ortho- and mono-ortho-substituted polychlorinated biphenyls (PCBs) in biological samples has been developed. High selectivity was obtained by on-line coupling of supercritical fluid extraction (SFE) and high-performance liquid chromatography (HPLC). Gas chromatography (GC) with electron capture detection or high-resolution mass spectrometry was utilized for quantitative determinations. Group separation of different PCB congeners was achieved on a (2-(1-pyrenyl)ethyl)dimethylsilylated silica column. Compared with off-line HPLC, the on-line coupling to SFE resulted only in a minor reduction in column efficiency. The average recoveries of the planar non-ortho-substituted PCB congeners 77, 126, and 169 from crab hepatopancreas were 71-101%, with the highest recovery for PCB-169. For human blood serum and milk, the recoveries of the three congeners ranged from 35 to 57% (serum) and from 76 to 87% (milk), with the lowest recovery for PCB-169. The relative standard deviations of the complete analyses were determined to be 5-16%. The recoveries of the on-line SFE-HPLC technique were compared to those of conventional solvent extraction and off-line HPLC. For crab hepatopancreas, the two methods gave approximately the same result, but for blood serum, slightly higher recovery of the native non-ortho-substituted PCBs was obtained using SFE-HPLC. The present method demonstrates the high speed and selectivity which were obtained by on-line SFE-HPLC as a sample preparation technique prior to GC analyses for the determination of a group of highly toxic PCBs, usually found in very low concentrations compared to the bulk of the PCB congeners.

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On-line coupled supercritical fluid extraction and gas chromatography (SFE-GC) has been utilized for the determination of PCBs and other organochlorine compounds in human milk and blood serum. The procedure involved preconcentration of the sample on Ct8-silica sorbent in an extraction cell: after precipitation of the proteins up to 20 ml of human milk was concentrated on 0.5 g of sorbent. Serum (up to 5 ml) was applied to the c 1 8 material without pretreatment. Basic alumina was utilized as a selective adsorbent for lipids in the on-line SFE-GC system. The method was used to analyze milk and serum spiked with 0.5 and 10 ng of Aroclor 1260 and the results compared with those obtained by liquid -liquid extraction of serum.