title: Evaluation of sensitizers found in wastewater from paper recycling areas, and their activation of the aryl hydrocarbon receptor in vitro.
abstract: The in vitro potential of sensitizers and related compounds (SRCs) originating from impurities in waste paper in activating the human aryl hydrocarbon receptor (AhR) α was assessed using yeast reporter gene as well as cytochrome P450 (CYP)1A1 and ethoxyresorufin O-deethylase (EROD) assays. In the yeast assay, eight compounds exhibited agonist activity, and their activity relative to β-naphthoflavone (BNF) ranged from 1.4 × 10(-4) to 8.3 × 10(-2), with the highest activity observed for benzyl 2-naphthyl ether (BNE). In the EROD assay, six compounds caused a more significant induction of CYP1A-dependent activity than did the vehicle control at 50 μM (p<0.01), and their induction levels were 5.1- to 11-fold more potent; 1,2-bis(3-methylphenoxy)ethane (BME) was the most effective inducer. The water from the waste paper recycling area was fractioned using solid-phase extraction (SPE) combined with a C18 disk and florisil cartridge. In gas chromatography-mass spectrometry (GC-MS) analysis, SRCs were detected in the first fraction, at a total concentration of 5.5 μg/L. This fraction also activated AhR, and its activity, expressed as a BNF equivalent value, was 0.42 nM in the yeast assay. The contribution ratio of active compounds accounted for up to 34% and 4.4% observed activity of the fraction and total samples, respectively. To our knowledge, this is the first study to show that paper industry-related compounds, namely aromatic sensitizers, activate AhR by using a yeast assay and HepG2 cells.
authors.affiliation: Institute for Environmental Sciences, University of Shizuoka, 52-1 Yada, Suruga-ku, Shizuoka 422-8526, Japan. Electronic address: terasaki@u-shizuoka-ken.ac.jp.
authors.forename: Masanori
authors.initials: M
authors.lastname: Terasaki
authors.affiliation: Institute for Environmental Sciences, University of Shizuoka, 52-1 Yada, Suruga-ku, Shizuoka 422-8526, Japan.
authors.forename: Michiko
authors.initials: M
authors.lastname: Yasuda
authors.affiliation: Institute for Environmental Sciences, University of Shizuoka, 52-1 Yada, Suruga-ku, Shizuoka 422-8526, Japan.
authors.forename: Kayoko
authors.initials: K
authors.lastname: Shimoi
authors.affiliation: Institute for Environmental Sciences, University of Shizuoka, 52-1 Yada, Suruga-ku, Shizuoka 422-8526, Japan.
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Jozuka
authors.affiliation: Institute for Environmental Sciences, University of Shizuoka, 52-1 Yada, Suruga-ku, Shizuoka 422-8526, Japan.
authors.forename: Masakazu
authors.initials: M
authors.lastname: Makino
authors.affiliation: Research Center for Environmental Risk, National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki 305-8506, Japan.
authors.forename: Fujio
authors.initials: F
authors.lastname: Shiraishi
authors.affiliation: Research Center for Environmental Risk, National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki 305-8506, Japan.
authors.forename: Daisuke
authors.initials: D
authors.lastname: Nakajima
mesh_terms: D051792:Basic Helix-Loop-Helix Proteins / Q000378:metabolism; D001681:Biological Assay; D019363:Cytochrome P-450 CYP1A1 / Q000378:metabolism; D004784:Environmental Monitoring; D004987:Ethers / Q000032:analysis* / Q000633:toxicity; D066298:In Vitro Techniques; D010209:Paper; D018336:Receptors, Aryl Hydrocarbon / Q000378:metabolism; D059027:Recycling; D062065:Wastewater / Q000737:chemistry* / Q000633:toxicity; D014874:Water Pollutants, Chemical / Q000032:analysis* / Q000633:toxicity
chemical_list: D051792:Basic Helix-Loop-Helix Proteins; D019363:Cytochrome P-450 CYP1A1; D004987:Ethers; D018336:Receptors, Aryl Hydrocarbon; D062065:Wastewater; D014874:Water Pollutants, Chemical; C111235:AHR protein, human; C102689:benzyl 2-naphthyl ether
keywords: Aromatic sensitizers; Effect-directed analysis; Human HepG2 ethoxyresorufin O-deethylase assay; Human aryl hydrocarbon receptor α; Paper mill effluent; Yeast YCM3 assay