• 한국항해항만학회지
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• 제26권5호
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• pp.505-510
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• 2002

본 논문은 국제해사기구 - 해양환경보호위원회 제46차(외교회의 결정 2001년 10월 5일)회의에서 유기주석계 방오도료 사용금지 (2003년 1월 1일 선체 사용금지, 2008년 1월 1일 선체 잔존금지)에 따른 국내 업계의 동향을 조사·분석하고 이를 바탕으로 유해방오시스템 협약과 연계된 국내법 마련(해양환경관리법 입법 방향, 선박안전법의 개정안)과 아울러 국제방오시스템증서 발급 방안, 효과적인 유해방오시스템 규제 방안(항만국 통제의 방안)을 마련하였다.

• Animal cells and systems
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• 제11권1호
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• pp.1-8
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• 2007

Recently, we have shown that some endocrine disruptors, heavy metals, organotins and azoles suppressed steroidogenic enzymes such as P450 side-chain cleavage enzyme (P450scc) and aromatase in bullfrog ovarian follicles. In the present study, by using an amphibian ovarian follicle culture system, we examined the effects of these endocrine disruptors on maturation and ovulation of oocytes from Rana dybowskii in vitro. Ovarian fragments or isolated follicles were cultured for 24 h in a medium containing frog pituitary homogenate (FPH) or progesterone ($P_{4}$) with or without endocrine disruptors, and oocyte maturation (germinal vesicle breakdown, GVBD) and ovulation were examined. Among the organotins, tributyltin (TBT) strongly inhibited both FPH-and $P_{4}-induced$ oocyte maturation ($ED_{50}$:0.6 and 0.7 ${\mu}M$, respectively); however, tetrabutyltin (TTBT) and dibutyltin (DBT) showed only partial suppression, while monobutyltin (MBT) showed no inhibitory effect. All of the organotins suppressed $P_{4}-induced$ oocyte ovulation very effectively at a low concentration, and TBT and DBT exerted an inhibitory effect on FPH-induced ovulation. Among the heavy metals, mercury (Hg), cadmium (Cd) and cobalt (Co) were very effective in inhibiting FPH-induced oocyte maturation and ovulation, while lead (Pb), arsenite (As) and zinc (Zn) were less effective. However, all of the heavy metals suppressed FPH-induced oocyte ovulation at a high dose ($100{\mu}M$). Among the azoles, itraconazole (ICZ), ketoconazole (KCZ) and clotrimazole (CTZ) effectively inhibited FPH-induced oocyte maturation and ovulation, while econazole (ECZ), miconazole (MCZ) and fluconazole (FCZ) were considerably less effective. These results demonstrated that the abovementioned endocrine disruptors exhibited differential effects on oocyte maturation and ovulation in amphibian follicles and that the frog ovarian culture system could be used as an effective experimental tool to screen and evaluate the toxicity of various endocrine disruptors in vitro.

• 한국발생생물학회지:발생과생식
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• 제13권3호
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• pp.163-172
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• 2009

Some organotin compounds such as butyltins and phenyltins are known to induce impo-sex in various marine animals and are considered to be endocrine disruptors. In this study, the effect of organotins on follicular steroidogenesis in amphibians was examined using ovarian follicles of Rana dybowskii and Rana catesbeiana. Isolated follicles were cultured for 6 or 18 h in the presence and absence of frog pituitary homogenate (FPH) or various steroid precursors, and the levels of product steroids in the culture media oassay. Among the butyltin compounds, tributyltin (TBT) strongly and dose-dependently inhibited the FPH-induced synthesis of pregnenolone ($P_5$) and progesterone ($P_4$) by the follicles. TBT also strongly suppressed the conversion of cholesterol to $P_5$ and partially suppressed the conversion of $P_5$ to $P_4$. A high concentration of dibutyltin (DBT) also inhibited steroidogenesis by the follicles while monobutyltin and tetrabutyltin had negligible effects. The toxic effect of TBT or DBT was irreversible and a short time of exposure (30 min) was enough to suppress steroidogenesis. All the phenyltin compounds significantly inhibited FPH-induced $P_5$ synthesis by the follicles. The effective dose of 50% inhibition by diphenyltin was $0.04\;{\mu}M$ and those of monophenyltin and triphenyltin were $0.24\;{\mu}M$ and $0.3\;{\mu}M$, respectively. However, none of the phenyltin compounds significantly suppressed the conversion of $P_4$ to $17{\alpha}$-hydroxyprogesterone ($17{\alpha}$-OHP) (by $17{\alpha}$-hydroxylase), $17{\alpha}$-OHP to androstenedione (AD) (by $C_{17-20}$ lyase), or AD to testosterone by the follicles. Taken together, the data show that among the steroidogenic enzymes, P450scc in the follicles is the most sensitive to organotin compounds and that an amphibian follicle culture system can be a useful screening model for endocrine disruptors.

• Bulletin of the Korean Chemical Society
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• 제26권3호
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• pp.440-446
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• 2005

A method is described for the determination of dibutyltin (DBT) in sediment by isotope dilution using liquid chromatography inductively-coupled plasma/mass spectrometry (LC-ICP/MS). To achieve the highest accuracy and precision, special attentions are paid in optimization and evaluation of overall processes of the analysis including extraction of analytes, characterization of the standards used for calibration and LC-ICP/MS conditions. An approach for characterization of natural abundance DBT standard has been developed by combining inductively-coupled plasma/optical emission spectrometry (ICP/OES) and LC-ICP/MS for the total Sn assay and the analysis of Sn species present as impurities, respectively. An excellent LC condition for separation of organotin species was found, which is suitable for simultaneous DBT and tributyltin (TBT) analysis as well as impurity analysis of DBT standards. Microwave extraction condition was also optimized for high efficiency while preventing species transformation. The present method determines the amount contents of DBT in sediments with expanded uncertainty of less than 5% and its result shows high degree of equivalence with reference values of an international inter-comparison and a certified reference material (CRM) within stated uncertainties.