An analytical method is descrlbed for measuring 2,3,7,8-tetrachiorodlbenzo-p dioxin (TCDD) and other TCDD IsomersIn human tlssue samples using a highly speclfic cleanup procedure and hlgh-resolution gas chromatography/high-resoiution mass spectrometry. The 2,3,7,8-TCDD Is quantlfied by the Isotope dilutlon technique with ["C1,]2,3,7,8-TCDD as the internal standard. Other TCDD isomers are estimated by use of relative response factors. The 1 part-per-trllllon (pptr) ilmk of detectlon is adequate for determlnlng 2,3,7,8-TCDD concentrations present in human adlpose tlssue specimens. Analytical accuracy is demonstrated by the results obtained In analyzing several spiked samples. The method Is shown to be unaffected by a number of potentially Interfering compounds. A series of quailty control material Is used to verify system performance. For samples containing 1.6 pptr 2,3,7,8-TCDD, a coefficient of variation (CV) of 19% is observed. For samples at the 8.4 pptr level, a CV of 11 % is observed.In recent reviews (1-3), the results of quantification of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) in biological samples by using various approaches to gas chromatography/mass spectrometry (GC/MS) instrumentation have been summarized. Fish are the most studied group of animals, followed by cattle.

Serum for reference pools of in vivo polychlorinated biphenyls (PCBs) was obtained from four goats that had received one dose (100 mg kg-1) of a selected technical Aroclor (AR) (1016, 1242, 1254 or 1260) and were allowed to recover for 30 d. These pools were used to assess the differences in an analytical method that determines and quantifies PCBs using packed-column gas chromatography (PCGC) (quantified on the basis of mean mass percent. data for grouped PCB peaks) and capillary-column gas chromatography (CCGC) (quantified on the basis of percent. composition data for specific congeners). With CCGC, results were statistically significantly different (p less than or equal to 0.0002) from results with PCGC for ARs 1016, 1242 and 1254 but not for AR 1260 (p = 0.23). When comparing these gas chromatographic methods using bovine serum spiked in vitro with the same ARs at 17-25 p.p.b., it was found that the methods were not statistically significantly different for any of the ARs (p = 0.30-0.92). Levels of serum PCB determined by the two methods for 12 persons, divided into two groups according to exposure, were compared using the paired t-test. Group 1 consisted of three persons with dietary and/or environmental exposure; one with dietary and/or environmental exposure in addition to occupational exposure dating back 20 years. Group 2 consisted of eight persons with recent occupational exposure.(ABSTRACT TRUNCATED AT 250 WORDS)

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Firemaster FF-1, a polybrominated biphenyl (PBB) mixture, was dissolved in corn oil and given as a dose of 200 mg/kg body weight to Sherman rats on d 7 and 14 of pregnancy. Control rats received equivalent doses of corn oil alone. Selected pups and all dams were killed 1 mo after pups were weaned. A total of 50 male and 50 female offspring per group were followed until they were 2 yr old. The livers of offspring killed at the ages of 2 mo and 2 yr had PBB levels of 2,4 (SD 1.2) and 0.8 (SD 0.65) mg/kg for females and 3.0 (SD 1.6) and 0.6 (SD 0.37) mg/kg for males, respectively. The incidence of hepatocellular carcinomas was 3/51 (5.9%) and 4/41 (9.6%) after 2 yr in females and males, respectively. Hepatocellular carcinomas were not observed among the controls. Neoplastic (hyperplastic) nodules of the liver were present in 9/51 (17.6%) and 2/41 (4.9%) of exposed females and males, respectively, whereas only 2/48 (4.2%) of control females and no control males had neoplastic (hyperplastic) nodules. Body weights were lower in PBB-exposed rats at ages 1, 6, 12, and 24 mo. Survival rates from birth to weaning were lower in PBB-exposed pups (89%) than in controls (98%). Mortality was two times higher in PBB-exposed males (64%) than in control males (32%) after 2 yr. Transplacental PBB exposure and exposure through milk resulted in PBB body burdens in the offspring still measurable at the end of their lifespan. These offspring had increased mortality rates and lower body weights than controls, and they developed hepatocellular carcinomas.