• Environmental Mutagens and Carcinogens
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• v.26 no.3
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• pp.69-76
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• 2006

2,3,7,8-Tetrachlorodibenzo-$\rho$-dioxin(TCDD) is a ubiquitous, persistent environmental contaminant and the most powerful carcinogen categorized by IARC. Although the mechanism of carcinogenesis by TCDD is poorly understood, several studies have shown that the skin is one of target organs far TCDD. In this study, we investigated the neoplastic transformation of human keratinocyte-derived cell line, HaCaT, by chemical transformation method using N-methyl-N'-nitro-N-nitrorsoguanidine(MNNG) and TCDD. We found that subsequent exposure to TCDD for 3 weeks after initial exposure to MNNG markedly induced transformed cells. It was suggested that TCDD can act as a potent promoter in HaCaT cells. Furthermore, these transformed cells showed morphological alternations in soft agar and increased telomerase activity. Therefore, the TCDD treatment of HaCaT cells by initiated with MNNG could promote neoplastic transformation without stimulation by exogenous growth factors. As a result, TCDD had a strong potency as a promoter in nontumorigenic immortalized human epidermal keratinocytes.

• Food Science and Biotechnology
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• v.27 no.6
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• pp.1843-1856
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• 2018

Tea is one of the most frequently consumed drinks due to its favourite taste and the health benefit. Tea is produced by several processes and drying is very important step to develop the flavour and destroys the enzymes in tea. However, during drying tea, polycyclic aromatic hydrocarbons some of which are carcinogen and genotoxin are naturally produced. The risk of PAHs by drinking tea was characterized by determining contents of 4 PAHs in tea. 4 PAHs including Benz(a)anthracene (BaA), Chrysene (CHR), Benzo(b)fluoranthene (BbF) and Benzo(a)pyrene (BaP) were investigated by GC-MS in total 468 tea products, which were contaminated up to $4.63ng\;g^{-1}$. Mate tea was the most highly contaminated by BaA, CHR, BbF and BaP and followed by Solomon's seal and Chrysanthemum. The Margin of Exposures calculated by the concentration of BaA, CHR, BbF and BaP and consumption amount of tea were higher than 10,000, and the risk of PAHs in tea were low concern to public health.

• Proceedings of the Korea Environmental Mutagen Society Conference
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• 2003.10a
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• pp.112-112
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• 2003

• Proceedings of the Korea Environmental Mutagen Society Conference
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• 2004.05a
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• pp.104-104
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• 2004

• Proceedings of the Korean Society of Developmental Biology Conference
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• 2002.02a
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• pp.51-51
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• 2002

• Proceedings of the Korean Society of Toxicology Conference
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• 2003.10b
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• pp.196-196
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• 2003

Food is a significant source of polycyclic aromatic hydrocarbons (PAHs) to which humans are exposed. In this study, we are analysed 14 PAHs in baked and smoked meats known as major source of PAHs, and defined a correlation between benzo(a)pyrene and pyrene to compare estimating risk from human exposure to PAHs with urinary1-hydroxypyrene.(omitted)

• Journal of Radiation Protection and Research
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• v.35 no.3
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• pp.96-98
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• 2010

Medical use of radiation is increasing in recent times and its influence on the population creates almost the same amount of annual natural background radiation in industrialized countries in particular. Thus, medical radiation has become a social issue. This paper is a brief report on the status of medical exposure in Korea by way of consulting from the radiation-related medical societies in Korea.

• The Korean Journal of Applied Statistics
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• v.33 no.2
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• pp.203-213
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• 2020

The self-controlled case series (SCCS) study measures the relative risk of exposure to exposure period by setting the non-exposure period of the patient as the control period without a separate control group. This method minimizes the bias that occurs when selecting a control group and is often used to measure the risk of adverse events after taking a drug. This study used SCCS to examine the increased risk of side effects when two or more drugs are used in combination. A conditional Poisson model is assumed and analyzed for drug interaction between the narcotic analgesic, tramadol and multi-frequency combination drugs. Bayesian inference is used to solve the overfitting problem of MLE and the normal or Laplace prior distributions are used to measure the sensitivity of the prior distribution.

• Analytical Science and Technology
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• v.22 no.6
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• pp.449-457
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• 2009

Total PCBs (62 congeners) has been determined in the retailed foods by the isotopic dilution method and the exposure assessment has been performed. Put into a food sample $^{13}C$-labeled standard for recovery was added and then it was extracted, cleaned-up by multi-layer column chromatography and then analyzed by HRGC/MS. The average levels (ng/g) detected was 0.1 for rice, 1.8~3.4 for meats, 0.3~3.7 for milk and dairy products, 10.0 for egg and 0.8~34.4 for fishes. Distribution of total PCBs was in order of fishes (94.4%) > meats (2.3%) > eggs (1.7%) > milk and dairy products (1.3%) > rice (0.3%). The estimated daily intake(EDI) was 14 ng/kg bw/day. It was concluded that there was no health risk at all.

• Proceedings of the Korea Environmental Mutagen Society Conference
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• 2001.10b
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• pp.175-175
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• 2001