title: Congener profiles of PCBs and PCDD/Fs in Yucheng victims fifteen years after exposure to toxic rice-bran oils and their implications for epidemiologic studies.
abstract: In 1978-1979, a mass poisoning occurred in central Taiwan from rice-bran oil contaminated by heat-degraded PCBs was later called the Yucheng (oil disease in Chinese). Only a few studies have so far investigated the levels of specific polychlorinated biphenyl (PCB) or polychlorinated dibenzodioxin/furan (PCDD/F) congeners in the Yucheng victims. This study aimed to investigate the serum residual levels of thirty-three PCBs and seventeen 2,3,7,8-substituted PCDD/F congeners in the Yucheng victims 15 years after the exposure. Forty-one blood samples were collected from individual Yucheng victims in 1994-1995. The mean levels of total 33 PCBs and 17 PCDD/Fs were 2468 ng/g lipid (13.3 ng/g sample) and 6550 pg/g lipid (30.9 pg/g sample) respectively. The higher levels were found in PCBs #99, #138, #153, #156, #170, #179, and #180 among 33 PCB congeners, while 2,3,4,7,8-PeCDF, 1,2,3,4,7,8-HxCDF, and OCDD had the higher concentrations among 17 PCDD/F congeners. The total TEQ was contributed in decreasing order by 10 PCDFs (44%), three non-ortho-PCBs (24%), six mono-ortho-PCBs (20%), and seven PCDDs (12%). The mean total PCB levels and TEQ value of the 17 PCDD/Fs in the Yucheng victims 15 years after the toxic exposure were still 9 and 46 times higher than those in the general population in Taiwan. Principle component analysis (PCA) indicated that seven PCB congeners, PCBs #99, #138, #153, #156, #170, #179, and #180, accounted for 73% of the total variances in PCBs. On the other hand, six PCDD/F congeners, 2,3,4,7,8-PeCDF, 1,2,3,4,7,8-HxCDF, 1,2,3,6,7,8-HxCDF, 1,2,3,6,7,8-HxCDD, 1,2,3,4,6,7,8-HpCDF, and OCDD, accounted for 97% of the total variances in PCDD/Fs. In addition, PCA revealed that at least three characteristic patterns of congener profiles for PCBs were observed among the Yucheng victims. Similar trend was also observed for PCDD/Fs. These patterns may reflect distinctive exposure scenarios and/or different metabolizing capabilities among the Yucheng victims. We suggest that these patterns, in contrast to total PCB and PCDD/F levels, may be valuable for the future epidemiologic studies when linking exposure with specific health effect.
authors.affiliation: Department of Environmental and Occupational Health, College of Medicine, National Cheng Kung University, 138 Sheng-Li Road, Tainan 704, Taiwan.
authors.forename: Jing-Fang
authors.initials: JF
authors.lastname: Hsu
authors.forename: Yue-Liang
authors.initials: YL
authors.lastname: Guo
authors.forename: Shu-Yao
authors.initials: SY
authors.lastname: Yang
authors.forename: Pao-Chi
authors.initials: PC
authors.lastname: Liao
mesh_terms: D000328:Adult; D001572:Benzofurans / Q000032:analysis / Q000493:pharmacokinetics* / Q000506:poisoning; D000072338:Dibenzofurans, Polychlorinated; D016021:Epidemiologic Studies; D005260:Female; D005506:Food Contamination; D006801:Humans; D008297:Male; D008875:Middle Aged; D010938:Plant Oils / Q000737:chemistry; D011078:Polychlorinated Biphenyls / Q000032:analysis / Q000493:pharmacokinetics* / Q000506:poisoning; D000072317:Polychlorinated Dibenzodioxins / Q000031:analogs & derivatives* / Q000032:analysis / Q000493:pharmacokinetics / Q000506:poisoning; D025341:Principal Component Analysis; D000073879:Rice Bran Oil; D013624:Taiwan; D013997:Time Factors; D014018:Tissue Distribution
chemical_list: D001572:Benzofurans; D000072338:Dibenzofurans, Polychlorinated; D010938:Plant Oils; D000072317:Polychlorinated Dibenzodioxins; D011078:Polychlorinated Biphenyls; D000073879:Rice Bran Oil