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140 Abstracts / Toxicology L

tructural similarities after ring opening with metabolites of BADGEerivatives, read-across from BADGE is adequate for these metabo-

ites. BADGE is not genotoxic and not carcinogenic in vivo. Notructural indications for genotoxic or carcinogenic properties wereredicted for cyclo-di-BADGE itself by Derek (Lhasa Ltd.). Simu-

ations in the VirtualToxLabTM followed by molecular dynamicsuggest that cyclo-di-BADGE binds to the estrogen receptors ER�/�nd, consequently, might act as a hormonally active substance (pre-icted binding affinity for ER� = 1.3 �M). Therefore, the threshold ofoxicological concern (TTC) concept is not applicable as this concepthould not be used for hormonally active substances. A toxicolog-cal evaluation of cyclo-di-BADGE is presently not possible basedn the available data. Further research is necessary on the systemicioavailability of cyclo-di-BADGE after oral administration and on

ts potential estrogenic and anti-estrogenic activities.

oi:10.1016/j.toxlet.2011.05.495

1262oxigenic fungi and ochratoxin A associated to nuts in Saudirabia

.M. Deabes 1,∗, R.E.S. El-Habib 2

Food Toxicology and Contaminants, National Research Center,airo, Egypt, 2 Department of Biology, College of Arts and Science,assim, Saudi Arabia

Purpose: The purpose of the survey was to determine levels ofchratoxin A and to monitor the effectiveness of the controls inlace to limit consumer exposure to ochratoxin A in nuts. Material:survey was carried out in July–September 2009 to obtain data

n the occurrence of ochratoxin A and the ochratoxin-producingotential of fungi isolated from nuts (almonds, peanuts, hazel-uts, pistachio nuts, walnut and cashew) in region of Qassim

n Saudi Arabia. The extraction is described using a simultane-us methanolic-aqueous extraction followed by immunoaffinityolumns clean-up step and determination by high pressure liquidhromatography (HPLC) with fluorescence detector (FD). The resultsf the study: The concentration of ochratoxin A in nuts samplealmonds, peanuts, hazelnuts, pistachio nuts, walnut) were rangedetween (2.0–3.2, 1.7–4.5, 1.4–3.5, 3.1–4.7, and 2.3–3.7) ng/g. How-ver cashew is free of ochratoxin A. 100% of samples showedariable incidence of fungal contamination. The predominant fungiresent in nuts samples were Penicillium spp., Aspergillus spp., andhizopus spp. Ochratoxin A (OTA) production has been detected by

solates Aspergillus section Nigri; and A. ochraceus isolated fromuts in high concentrations.

oi:10.1016/j.toxlet.2011.05.496

1263xamination of extracts from iced-teas on regulatoryathways of drug-metabolizing enzymes in humanepatocytes and cell lines

. Dvorak 1,∗, A. Kamenickova 2, R. Vrzal 2

Department of Cell Biology and Genetics, Palacky Universitylomouc, Olomouc, Czech Republic, 2 Palacky University Olomouc,lomouc, Czech Republic

Major drug-metabolizing cytochromes P450 are inducible byariety of xenobiotics. The induction occurs via xenoreceptors PXRnd AhR. Induction of CYPs by drugs causes so called drug–drug

205S (2011) S60–S179

interactions. The drugs that induce P450s must be prescribed withprudence and the dose of co-administered drugs must be adjusted.We are daily exposed to many compounds contained in a diet,including natural compounds, dyes, food additives, odorants, etc.These compounds may induce P450s, with consequences in drugmetabolism and expression of PXR- and AhR-driven genes. Wehave examined extracts from flavored iced-teas for their capabil-ity to activate PXR and AhR and to induce CYP1A1/2 and CYP3A4genes. Primary cultures of human hepatocytes and cancer celllines HepG2 and LS174T were used. Techniques of RT-PCR, west-ern blot and gene reporter assays were employed. We have tested23 different iced-teas from 4 brands that are marketed in CzechRepublic. We found that extracts from several iced-teas, e.g. redtea (pear) and black tea (forest fruit), displayed capacity to trans-activate CYP1A1 and CYP3A4 promoters in transiently transfectedHepG2 and LS174T cell lines, respectively. The data from genereporter assays were not always correlated with CYP1A1/2 andCYP3A4 expression in human hepatocytes, implying the role ofmetabolism in activation/inactivation of the constituents containedin the extracts. Frequent (regular) drinking of iced-teas could be asource of drug interactions and could cause alterations in carbohy-drate, lipids and bile acids homeostasis.

Acknowledgements: Our laboratory is supported by thegrants from the Czech Scientific Agency GACR503/10/0579 andGACR304/10/0149.

doi:10.1016/j.toxlet.2011.05.497

P1264Stable isotope ratios of nitrogen and carbon and mercuryconcentration in hair of Taiji residents, a Japanese whalingtown

T. Endo 1,∗, O. Kimura 1, Y. Hisamichi 1, K. Haraguchi 2

1 Health Sciences University of Hokkaido, Kanazawa, Japan, 2 DaiichiCollege of Pharmacy, Fukuoka, Japan

Mercury (Hg) level in head hair of Taiji residents who ate whalemeat was significantly higher than that of non-eater in Japan (Endoand Haraguchi, 2010). In this study, we analyzed stable isotoperatios of carbon (�13C) and nitrogen (�15N) in the hair of whale-eater in Taiji residents (n = 42) and compared with those of thenon-eater (n = 38). Furthermore, we analyzed the �13C and �15N andthe Hg concentration in the meats of pilot whale (n = 9), yellowfintuna (n = 16) and albacore tuna (n = 23) sold in Taiji market.

The �15N in whale-eater was significantly higher than that inthe non-eater (10.15 ± 0.55‰ vs 9.15 ± 0.43‰, p < 0.05) while the�13C was similar level (−18.8 ± 0.58‰ vs −18.9 ± 0.57‰). The Hgconcentration in the hair of whale eater was significantly higherthan that of non-eater (21.4 ± 14.2 �g/g vs 1.8 ± 1.7 �g/g, p < 0.05).The Hg concentration in the meat of whale (10.8 ± 4.5 �g/g)was extremely hither than that of yellowfin and albacore tuna(0.31 ± 0.26 �g/g and 0.42 ± 0.14 �g/g, respectively) (p < 0.05), andthe �15N in the former (12.2 ± 0.7‰) was significantly higherthan that in the latter (10.4 ± 1.4‰ and 10.4 ± 1.2‰, respectively)(p < 0.05). Significant positive correlations were found between the�13C and �15N values and between the �15N value and the Hg con-centration in the hair of whale-eater (p < 0.05), while significantcorrelations were not found in the non-eater.

These results suggest that the consumption of whale meat15

increases not only the Hg concentration but also the � N value

in the hair.

doi:10.1016/j.toxlet.2011.05.498