title: Occurrence of PCDD/PCDFs and PCBs in soil and comparison with CYP1A response in PLHC-1 cell line.
abstract: The responsiveness of CYP1A (gene transcription and EROD enzyme activity) in the cell line Poeciliopsis lucida hepatoma (PLHC-1) upon exposure to extracts of contaminated soil samples was investigated and compared to levels of PCDD/PCDFs and PCBs including non-ortho obtained by GC/MS analysis. Soil samples A and B were collected in sites A and B. Two fractions, not purified (np) and purified (p), were obtained from each sample and analyzed for PCDD/PCDF and PCB content by GC/MS; in parallel they were tested for 24 h with PLHC-1. CYP1A response was investigated at gene (RT-qPCR) level and as 7-ethoxyresorufin-O-deethylase (EROD) enzyme activity. Chem-TEQs and Bio-TEQs were then calculated. ∑TEQ calculated for PCDD/Fs and PCBs was 0.081 pg/g and 20.32 pg/g for samples A and B, respectively. PLHC-1 showed less up-regulation of cyp1a gene on exposure to the two purified fractions (Ap 2.1-fold and Bp 1.8-fold) than to non-purified fractions (up to 15-fold for Anp and 13-fold for Bnp). EROD was also induced 2.38- and 9.44-fold in the two purified fractions (Ap and Bp) compared to model inducer 2,3,7,8-TCDD, and up to 16.03-fold for non-purified Anp and 33.79-fold for Bnp. The combination of CYP1A response, obtained in a PLHC-1 cell-based bioassay, with contaminant residue analysis provided a better description of the presence and toxicity of dioxin-like compounds in an environmental matrix.
authors.affiliation: Department of Physical, Earth and Environmental Sciences, University of Siena, Siena, Italy. dellatorre2@unisi.it
authors.forename: Camilla
authors.initials: C
authors.lastname: Della Torre
authors.forename: Michela
authors.initials: M
authors.lastname: Mariottini
authors.forename: Anzhela
authors.initials: A
authors.lastname: Malysheva
authors.forename: Silvano Ettore
authors.initials: SE
authors.lastname: Focardi
authors.forename: Ilaria
authors.initials: I
authors.lastname: Corsi
mesh_terms: D000818:Animals; D001189:Aryl Hydrocarbon Hydroxylases / Q000378:metabolism*; D001572:Benzofurans / Q000032:analysis* / Q000633:toxicity; D045744:Cell Line, Tumor; D019363:Cytochrome P-450 CYP1A1 / Q000378:metabolism; D000072317:Polychlorinated Dibenzodioxins / Q000031:analogs & derivatives* / Q000032:analysis / Q000633:toxicity; D011108:Polymers / Q000032:analysis* / Q000633:toxicity; D012987:Soil / Q000737:chemistry
chemical_list: D001572:Benzofurans; D000072317:Polychlorinated Dibenzodioxins; D011108:Polymers; D012987:Soil; C016068:polychlorodibenzofuran; D001189:Aryl Hydrocarbon Hydroxylases; D019363:Cytochrome P-450 CYP1A1