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In aquatic invertebrates, particularly marine gastropods, organotin compounds induce irreversible sexual abnormality in females, which is termed imposex, at very low concentrations. Organotin compounds are agonists for nuclear receptors such as RXRs and PPARγ. However, the imposex phenomenon has not been reported to act as an antagonist on estrogen receptors in other species, including vertebrates and invertebrates. In order to gain insights into the antagonistic activity of organotin compounds on estrogen receptors (ERs), we examined the inhibitive effect of these compounds on estradiol-dependent β-galactosidase activity using the yeast two-hybrid detection system consisting of a combination of the human estrogen receptor (hERβ) ligand-binding domain and the co-activator steroid receptor co-activator-1 (SRC1). Tributyltin-hydroxide (TBT-OH) and triphenyltin-chlorine (TPT-Cl) exhibited an inhibitive effect on E 2-dependent transcriptional activity, similar to antagonistic chemicals such as 4-hydroxytamoxifen (OHT) or ICI 182,780, at a very low concentration of 10-14 M TBT or 10-10 M TPT, respectively. The yeast growth and transcriptional activity with transcriptional factor GAL4 did not exhibit any effect at the tested concentration of TBT or TPT. Moreover, the yeast two-hybrid system using the interaction between p53 and the T antigen of SV40 large did not describe any effect at the tested concentration of OHT or ICI 182,780. However, the interaction between p53 and T antigen was inhibited at a TBT or TPT concentration of 10-9 M, respectively. These results indicate that TBT and TPT act as inhibitors of ER-dependent reporter gene transcriptional activation and of the interaction between hERβ LBD and the co-activator SRC1 in the yeast two-hybrid system. Consequently, our data could partly explain the occurrence of organotin compoundinduced imposex on the endocrine system of mammals, including humans.

Since volatile organic compounds (VOCs) and formaldehyde (HCHO) associates with building and finishing materials such as paints, varnishes, and adhesives, the emission rates of VOCs and HCHO in indoor environments of newly constructed apartment according to floor levels were estimated using mass balance model. Mean indoor concentrations of benzene, toluene, styrene, and HCHO in middle floors were higher than those in low and high floors, whereas mean emission rates of VOCs in high floors were higher than those in middle and low floors. Mean indoor HCHO concentration in middle floor was significantly higher (p=0.001) than those in low and high floors, whereas the emission rates was not significant difference from those in low and high floors. The results could be explained that higher ventilation rates in high floors affect the indoor air quality as well as the emission rates of VOCs and HCHO. Considering the emission rates and indoor concentrations of VOCs and HCHO, it is suggested that apartment should be designed and constructed using materials emitting low hazardous air pollutants, with provision of decent ventilation.

The purpose of this study was to assess current exposure of the population living in the Gwangyang industrial complex and other areas to heavy metals and, VOCs and to identify individual factors associated with urinary and blood levels of these chemicals. The study population was made up of 810 participants ranging in age from 7 to 87 years old at Gwangyang bay in the South Korea. The selected biomarkers represent the main agents to which a population like that of Korean is exposed every day, including 4 heavy metals in blood or urine (Pb in blood and As, Cd, Hg in urine), and VOCs in blood descriptive data analysis leads to mean concentrations of heavy metals, As, Cd, Hg and Pb of 7.34 μg/g cr, 1.04 g/g cr, 1.33 μg/g cr and 2.53 μg/dL, respectively. The mean concentration of benzene, ethylbenzene, tetrachloroehylene, toluene, m-/p-xylene and o-xylene in blood were 0.00 μg/ L, 0.00 μg/L, 0.00 μg/L, 0.03 μg/L,0.00 μg/L and 0.00 μg/L, respectively. The DNA microarray analysis using blood of 16 participants, control group (n=6) and sample group (n=10), showed that the two groups might belong to a different group through hierarchical clustering the present study provides reference values for selected pollutants for the general population in industrial complexes, which can be used for comparison purposes in further studies, since they are mostly within the reference ranges reported by other biomonitoring studies therefore, it would be possible to devise standards for identifying the environmental pollution and beforehand forecast. In addition, it will be the one of the scientific method to help reduce anxiety of residents lived in the polluted areas.

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