• Toxicological Research
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• v.17
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• pp.37-39
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• 2001

As the preliminary data collection for further chemical risk assessment. toxicants rating works is now rather extensively implemented in China. It consists of two parts, ie., rating of the hazard level of the exposed toxicant and that of the toxicant's profession. In the first part, the rating are based on six criteria, ie., acute toxicity, incidence of acute poisoning, prevalence of chronic poisoning, consequence of chronic poisoning, carcinogenecity and MAC level. Four hazardous levels are to be classified as extreme, high, medium, mild. In the second part. three determinants as weighted coefficients are taken into account, ie., toxicant's hazard level. exposure time and folds of MAC surpassing. Eventually, the index of classification C by which the work with toxic hazard can be classified is able to be calculated and assessed. Several comments were discussed and new recommendations were demonstrated.

• Journal of Microbiology and Biotechnology
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• v.7 no.4
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• pp.242-249
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• 1997

Stability of bioluminescence was investigated with Photobacterium phosphoreum immobilized on the strontium alginate in order to develope continuous real time monitoring of pollutants. The stability of bioluminescence emission was improved by prolonged aging time. The aging time of ${\geq}40$ min and the cell concentration of ${\leq}0.6\;of\;OD_660$ were selected for the immobilization of P. phosphoreum to give linearity between cell concentrations and bioluminescence intensity. In sensitivity tests using phenol, it was found that this compound quenched bioluminescence proportional to the concentration without lowering of cell growth. The lower value for maximum quenching ($q_s$) and higher dissociation constant ($K_s$) were observed with strontium-alginate immobilized cells compared to free cells. The response of bioluminescence to toxicants was evaluated with the immobilized luminescent bacteria. The sensitivity of the immobilized cells was found to be good in response to toxicants, 4-nitrophenol, salicylate and cadmium, when evaluated with a specific rate of bioluminescence quenching.

• Environmental Analysis Health and Toxicology
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• v.22 no.1 s.56
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• pp.1-8
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• 2007

Biological monitoring, analyses of internal dose for exposure to toxicants, has been thought as one of the belt approaches for risk assessment. As the amount detected in human samples is generally very low, typically in the parts-per-bilion (ppb) or parts-per-trillion (ppt) range, analytic technologies such at HPLC, GC/MS, LC/MS, and LC/MS/MS have been continuously developed. In addition, route specific and sensitive exposure biomarkers have been developed for proper biological monitoring. PBPK modeling, particularly reverse dosimetry, has been emphasized as an useful method via interpretation of biological monitoring results for regulation of toxicants. Thus, this review is focused on the use of PBPK dosimetry models for toxicology research and risk assessment in Korea.

• 한국생물공학회:학술대회논문집
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• 2002.04a
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• pp.53-56
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• 2002

Mammalian cell based biosensor kits are expected to be in assessment of samples toxicity more sensitive and accurate. A recombinant fluorescent Chinese Hamster Ovary (CHO) cell line was known to be responsive to the various toxicants Specially. KFC- AlO cell line. which contain the c-fos SRE::GFP plasmid (pKFG). was found to be able to detect toxicants sensitively. A biosensor kit was developed by using an immobilized KFC-A10 cell line. Immobilized recombinant fluorescent cells within agarose, known as a representative hydrogel matrix, have been maintained in the matrix viably and have shown constant fluorescent levels for long time. Immobilized cells have shown the ability to detect the chemical toxicity in the keep of fluorescent level as the metabolism is inhibited under toxic conditions.

• Proceedings of the Korean Society of Toxicology Conference
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• 2006.11a
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• pp.34-45
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• 2006

Chemical toxicants are metabolically converted to numerous metabolites in the body. Toxicokinetic characteristics of metabolites could be therefore used as biomarker of exposure for human risk assessment. Biologically based dose response (BBDR) model was proposed for future direction of risk assessment. However, this area has not been developed well enough for human application. Benzo(a)pyrene (BP), for example, is a well-known environmental carcinogen and may produce more than 100 metabolites and BPDE-DNA adduct, a covalently bound form of DNA with benzo(a)pyrene diolepoxides (BPDES), has been applied to qualitatively or quantitaively estimate human exposure to BP. In addition, di(2-ethylhexyl) phthalate (DEHP), a widely used plasticize. in the polymer industry, is one of endocrine-disrupting chemicals (EDCs) and has been monitored in humans using urinary or serum concentrations of DEHP or its monomer MEHP for exposure and risk assessment. However, it is difficult to estimate the actual level of toxicants using these biomarkers in humans using. This presentation will discuss a methodology of exposure and risk assessment by application of metabolic profiling kinetics.

• Journal of the Korean Society of Food Science and Nutrition
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• v.21 no.4
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• pp.341-347
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• 1992

In search for new drugs and methods of pharmacotherapy of liver damage , the pollen extracts was administrated to the experimental animals and ivnestigated its biochemical effects in the serum and liver when aromatic hepatotoxicants-phenybutazone, aniline and benzo(a) pyrene-was administered. As the results are the pretretment of azalea pollen was prevented the leakage of asartate aminotransaminase (AST), alanine aminotransfease(ALT), alkaline phosphatase (ALP) activity and bilirubin level to serum and liver, except serum lactate dehydrogenase (LDH) activity.

• Biotechnology and Bioprocess Engineering:BBE
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• v.11 no.6
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• pp.516-521
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• 2006

The use of gltA gene, as a new biomarker for environmental stress biomonitoring, was investigated because of its key position as the first enzyme of the tricarboxylic acid (TCA) cycle. A recombinant bioluminescent Escherichia coli strain, EBJM2, was constructed using a plasmid carrying the citrate synthase (gltA) promoter transcribing the Photorhabdus luminescens IuxCDABE genes (gltA::luxCDABE). The responses from this strain were studied with five different classes of toxicants: DNA damage chemicals, phenolics, oxidative-stress chemicals, PAHs, and organic solvents. EBJM2 responded strongly to DNA damage chemicals, such as mitomycin C (MMC) and methyl-nitro-nitrosoguanidine (MNNG) and nalidixic acid with the strongest responses. In contrast, tests with several compounds from the other four classes of toxicants gave no significant response. Therefore, EBJM2 was found to be sensitive to DNA damage chemicals.

• Proceedings of the Korea Society of Environmental Toocicology Conference
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• 2006.05a
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• pp.49-52
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• 2006

• Journal of Life Science
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• v.10 no.3
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• pp.247-253
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• 2000

The effects of acute of marine toxicants on early life of coastal olive flounder were investigated. An increasing order of acute toxicity on embryo- and larva-stages of Paralichtys olivaceus was CdCl2$\mu\textrm{g}$/L and 29 $\mu\textrm{g}$/L, respectively, and those values at larva-stage were estimated 3.5 ng/L, 16.0 nL/L, 10.5 $\mu\textrm{g}$/L and 15.0 $\mu\textrm{g}$/L, respectively.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.15
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• pp.6121-6125
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• 2014

Background: Prostate-specific antigen (PSA) is a potential biomarker for early detection of prostate cancer (PCa) but its level is known to be affected by many background factors and roles of ubiquitous toxicants have not been determined. Endocrine disrupting chemicals (EDCs) are ubiquitous reproductive toxicants used in consumer products, which promote tumor formation in some reproductive model systems by binding to AhR, but human data on its expression in prostate cancer as well as its association with PSA levels are not clear. This study aimed to evaluate the expression levels of AhR and its association with serological levels of PSA and to detect possible effects of background factors and EDC exposure history on PSA levels in PCa cases. Materials and Methods: A cross-sectional study was conducted on the tissue levels of AhR and serum levels of PSA in 53 PCa cases from 2008-2011 and associations between each and background and lifestyle related factors were determined. Results: Although the AhR was overexpressed in PCa and correlated with the age of patients, it did not correlate with PSA levels.Of nutritional factors, increased intake of polysaturated fats and fish in the routine regimen of PCa cases increased the PSA levels significantly. Conclusions: AhR overexpression in PCa pontws to roles of EDCs in PCa but without any direct association with PSA levels. However, PSA levels are affected by exposure to possible toxicants in foods whichneed to be assessed as possible risk factors of PCa in future studies.