title: Validation of the CALUX bioassay for the screening of PCDD/Fs and dioxin-like PCBs in retail fish.
abstract: The chemical-activated luciferase expression (CALUX) assay is a reporter gene assay that detects dioxin-like compounds based on their ability to activate the aryl hydrocarbon receptor (AhR) and thus expression of the reporter gene. In this paper, the CALUX assay was examined for its application in the screening of polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs) and dioxin-like polychlorinated biphenyls (dioxin-like PCBs) in retail fish. The sample extracts were cleaned up on a sulfuric acid-silica gel column followed by an activated carbon column, and the AhR activity of the separated PCDD/F and dioxin-like PCB fractions was determined using the assay. The quantitative limit for 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD) was 0.98 pg ml(-1) (0.19 pg assay(-1) in the standard curve, corresponding to 0.16 pg g(-1) of CALUX-based toxic equivalency (2,3,7,8-TCDD equivalents) in the tested sample. Recovery tests in which dioxins were added to fish samples resulted in acceptable recoveries (77-117%). The CALUX assay performed well in the analysis of dioxins in fish samples and a comparative study revealed a strong correlation between the CALUX assay and high-resolution gas chromatography-high-resolution mass spectrometry analysis for the determination of PCDD/Fs (r = 0.89) and dioxin-like PCBs (r = 0.91) in retail fish (n = 22). These data revealed that the CALUX assay would be a useful screening method for PCDD/Fs and dioxin-like PCBs in retail fish.
authors.affiliation: Division of Foods, National Institute of Health Sciences, 1-18-1 Kamiyoga, Setagaya-ku, Tokyo 158-8501, Japan.
authors.forename: Tomoaki
authors.initials: T
authors.lastname: Tsutsumi
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Amakura
authors.forename: Masafumi
authors.initials: M
authors.lastname: Nakamura
authors.forename: David J
authors.initials: DJ
authors.lastname: Brown
authors.forename: George C
authors.initials: GC
authors.lastname: Clark
authors.forename: Kumiko
authors.initials: K
authors.lastname: Sasaki
authors.forename: Masatake
authors.initials: M
authors.lastname: Toyoda
authors.forename: Tamio
authors.initials: T
authors.lastname: Maitani
mesh_terms: D000818:Animals; D001572:Benzofurans / Q000032:analysis*; D001681:Biological Assay / Q000379:methods; D002274:Carcinogens, Environmental / Q000032:analysis*; D005399:Fishes; D005506:Food Contamination / Q000032:analysis*; D015870:Gene Expression; D017930:Genes, Reporter; D008156:Luciferases / Q000235:genetics; D011078:Polychlorinated Biphenyls / Q000032:analysis*; D000072317:Polychlorinated Dibenzodioxins / Q000031:analogs & derivatives* / Q000032:analysis*
chemical_list: D001572:Benzofurans; D002274:Carcinogens, Environmental; D000072317:Polychlorinated Dibenzodioxins; C023614:dibenzofuran; D011078:Polychlorinated Biphenyls; D008156:Luciferases