• Proceedings of the Korean Environmental Health Society Conference
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• 2005.06a
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• pp.11-44
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• 2005

The occurrence of toxic cyanobacterial blooms has been reported worldwide and pose a threat to human health through drinking water exposure. The toxins they produced are highly water soluble and can leach into the water body. To eliminate any risk of drinking water exposure, removal of these toxins is essential before the water is consumed. Conventional water treatment techniques such as chlorination, if managed well, can be effectively used to remove some of these toxins, however, saxitoxin and derivatives pose a problem. Little toxicological data are available to evaluate the real threat of these toxins.

• 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.

• Toxicological Research
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• v.17
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• pp.219-225
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• 2001

The basic structure for assessment of potential health risks from environmental chemicals is widely agreed upon, but many of the details of risk assessment procedures differ among practitioners. Government regulatory agencies typically have guidelines or standard procedures for their risk assessments, established to ensure consistency and comparability, to set standards for adequacy, and to embody underlying tenets. In setting and updating such guidelines, each agency takes into account not only the prevailing thinking about appropriate procedures, but also its own goals and responsibilities and the precedents it has set for itself in past analyses. This results in variations in methods, and consequently in characterization of risks, among regulatory assessments, even when they are based on the same data. As a result, adopting existing assessments from a variety of regulatory bodies needs to be done with caution. This paper examines some of the variants in risk assessment approaches among American federal regulatory agencies and relates them to the variations in regulatory responsibilities of those groups. Comparisons to international practices are also drawn. The impact on development of world-wide risk standards is discussed.

• Toxicological Research
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• v.16 no.4
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• pp.311-315
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• 2000

Previous studies showed that benzoquinone derivatives inhibited platelet aggregation. but there is no information available on their cytotoxicity to platelets. 1n the present study. washed platelets isolated from rats were treated with 1.4-benzoquinone. a representative benzoquinone derivative. to examine its antiaggregating effect and cytotoxicity. 1.4-Benzoquinone significantly inhibited thrombin-induced platelet aggregation. Consistent with this finding. 1.4-benzoquinone suppressed cytosolic calcium increase induced by thrombin. To examine the cytotoxicity by 1 A-benzoquinone in platelets. turbidometry and lactate dehydrogenase release were measured. Treatment with 1.4-benzoquinone resulted in slight cytotoxicity (30% release at 60 min) to platelets. However. the cytotoxicity was not correlated with increase of cytosolic calcium levels in platelets. All these data suggested that 1.4-benzoquinone inhibited thrombin-induced platelet aggregation mediated by inhibition elf calcium level increase and that 1.4-benzoquinone reveals cytotoxicity to some extent without alteration of calcium level in platelets.

• Environmental Analysis Health and Toxicology
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• v.4 no.1_2
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• pp.55-65
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• 1989

Nevertheless the serious environmental pollution in Korea has been discussed in concern with health effect, the significant effect are not determined easily. Toxicological method has been used to establish safe levels of exposure for environmental pollutants to have threshold health effect below which significant effects are unlikely to occur. However the conventional method cannot to establish safe levels of exposure for non-threshold pollutants have been used to express comprehensive pollution degree, not in detailed toxic effects. Acceptable exposure or risk levels are decides by policymakers who consider descriptions and estimates of risks together with social and economic benefits. This paper focuses on the concept development of risk assessment and describes some risks of environmental pollution based on the surveyed date in Korea. The current concepts of risk assessment in policy descisions can be explored and areas for possible improvement, given current scientific knowledge are identified. The experience of foreign countries can provide a realistic basis for evaluating the existing data of environmental pollutants. To improve the environmental quality, risk regulation should be managed as soon as possible in Korea.

• Toxicological Research
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• v.11 no.2
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• pp.289-294
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• 1995

This study was designed to observe the effect of tohiene pretreatment on leukocyte variation in whole blood and the oxygen free radical generating, scavenging enzyme activities in neutrophil of bacteria infected rats. Toluene was administered 7 times intraperitoneally at levels of 9.45 mM/kg body weight to the rats and then infected with S. aureus $2\times10^7$ cfu/ml. The toluene treated-rats showed the significantly decreased numbers of lymphocyte and monocytes, but the similiar numbers of neutrophils with the control. Furthermore the increased neutrophils in blood of bacteria infected rats were reduced by the toluene pretreatment. Concomitantly the increased activities of xanthine oxidase and superoxide dismutase in neutrophil of bacteria infected rats were also decreased by the toluene pretreatment. On the other hand, injection of benzaldehyde to rats also led to similiar results in the count of leukocytes, xanthine oxidase and superoxide dismutase activities of neutrophil with those of toluene treated rats. These data suggest that toluene and its intermediate metabolite, benzaldehyde influence on the phagocytosis and defence mechanism of neutrophil.

• Toxicological Research
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• v.21 no.4
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• pp.319-323
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• 2005

The aim of the present study was to evaluate systemic bioavailability of surfactin and to determine its pharmacokinetic profiles. The stability of surfactin to pH, temperature and protease was evaluated. Surfactin was resistant to high temperature, a wide range of pH and the action of hydrolytic enzymes. The pharmacokinetic natures of surfactin which were shown the short half-life, rapid clearance and poor bioavailability. The results of study should provide preliminary data of surfactin for further dose-finding studies and for the design of application forms. It is also be important to a context of the safety of surfactin.

• Toxicological Research
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• v.18 no.2
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• pp.191-194
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• 2002

3-Monochloro-1,2-propanediol(3-MCPD) was analyzed in soy sauce products commercially available in Korea. A total of 24 samples were collected and 3-MCPD was determined by GC/MS. Sources of 24 samples were classified by manufacturing methods as naturally brewed(NB), acid hydrolyzed (AH) and mixed (M = NB + AH) soy sauces. 3-MCPD was not detected in NB soy sauce products (< 0.01 ppm, mg/kg) whereas AH and M soy sauce products showed a wide range of 3-MCPD contamination (0.0l ∼ 2.038 ppm). The contaminated levels of 3-MCPD in soy sauce products were higher than the permissible or tentative permissible level of 3-MCPD in both European Community (0.02 ppm) and Korea (0.3 ppm). These data suggest that 3-MCPD levels contaminated in soy sauce products in Korea were shown to be too high and should be reduced to as low a level technologically feasible to protect Korean from the exposure to toxic chemical, 3-MCPD.

• Toxicological Research
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• v.18 no.3
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• pp.267-273
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• 2002

Fructose 1,6-diphosphate(FDP), a glycolytic metabolite, is reported to ameliorate inflammation and inhibit the nitric oxide production in murine macrophages stimulated with endotoxin. It is also reported that FDP has cytoprotective effects against hypoxia or ischemia/reperfusion injury in brain and heart, and may play a protective role in ultraviolet B (UVB, 280~320 nm)-injured keratinocyte by attenuating prostaglandin (PG)-E$_2$production and cyclooxygenase (COX)-2 expression, which are possibly through blocking the intracellular reactive oxygen species (ROS) accumulation. Therefore FDP is considered to act as a potent antioxidant especially in the skin. We conducted the several safety tests (single-dose toxicity, primary skin irritation test, eye irritation test, skin sensitization test, phototoxicity test, photosenitization test and human patch test) to see if FDP is safe in case used for the skin application. Our data obtained hitherto suggest that FDP is very safe if applied to the skin.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.13 no.2
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• pp.75-78
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• 2007

Regulation of food packaging in Korea, Eurpoe and USA are surveyed. Food packaging manufacturer or converter has a responsibility to evaluate the safety of migration of harmful materials from typical finished packaging items. The 'overall migration limit' of all components from the packaging and 'specific migration limits(SML)' of monomers or additives are evaluated with food simulants, water, acetic acid, ethanol and n-heptane, based on the regulations of the countries. A substance not regulated has to be authorized with the technical data required, information on chemical identity, physical chemical and other properties, the intended use, migration studies and toxicological studies.