• Analytical Science and Technology
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• v.20 no.1
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• pp.84-90
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• 2007

To determine levels of 11 sulfonamides for animals in food, simultaneously, a selective method of high performance liquid chromatography with UV detector has been applied. The targets were sulfachlorpyridazine (SCP), sulfadiazine (SDZ), sulfadimethoxine (SDM), sulfisoxazole (SSX), sulfamerazine (SMZ), sulfamethazine (SMT), sulfamethoxazole (SMX), sulfamethoxypyridazine (SMP), sulfamonomethoxine (SMM), sulfaquinoxaline (SQX) and sulfathiazole (STZ). Food samples were beef, pork, chicken, milk and whole egg that were collected at the main 6 cities in Korea as Seoul, Busan, Daejon, Incheon, Mokpo and Gangneung. After homogenizing food samples with sodium phosphate solution and acetonitrile, it was extracted with n-hexane. The mobile phase gradient was a mixture of 5 mM potassium phosphate (pH 3.25) and methanol with a gradient ratio from 100:0 to 30:70. The UV wavelength was 270 nm. The overall recoveries were ranged from 75% to 95% and the limit of detection was minimum 0.004 mg/kg for SMT, and 0.007 mg/kg for STZ at signal/noise > 3, respectively. As results, sulfonamide drugs were not detected in most of the selected food samples, however, sulfamonomethoxine was detected in meat. The determined level of sulfamonomethoxine were 0.03 and 0.06 mg/kg for beef that were below the MRLs.

• Environmental Analysis Health and Toxicology
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• v.31
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• pp.15.1-15.6
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• 2016

A number of absurdities surrounding the humidifier disinfectant (HD) incident may have occurred because 1) a judicial system operates on the underlying false assumption that the involved parties are equals in knowledge, information and resource mobilization capabilities, regardless of respective real status as company or individual; 2) there is a lack of a system that mandates a company to prevent and actively manage possible catastrophes; 3) the regulatory scheme makes companies believe that as long as they are complying with the existing regulations, they have satisfied all of their responsibilities. I believe that this issue is an opportunity to bring about changes in the judicial redress system, the system of internal management of manufacturers, and the regulatory system of the government. The following regulation amendments are needed to move towards the changes stated above. First, legislation relating to victim relief that is applicable to the HD incident must be established. Second, a risk management system must be formed within the manufacturing company and to this end an institutional environment for the system must be established within regulatory framework. Furthermore, legislation must be passed that could punish companies themselves that have caused severe damage to individuals because they had failed to take necessary actions to avoid foreseeable harm. Finally, the framework of regulation must be changed so that the company, who has the necessary information regarding the product and the component chemicals used in the product, must self-directed experiment and assessment of the safety of their own products.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.23 no.2
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• pp.156-163
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• 2013

Objectives: Numerous poisonous substances are used in paint manufacture, but there are differences in the results of GHS classification between the Ministry of Labor(MOL) and the Ministry of Environment(MOE). Therefore, paint manufacturers suffer confusion as to how to classify a given chemical's risk and hazard level. This paper was designed to compare the classification results of chemicals by the MOL and the MOE and suggest a harmonization measure. Methods: After selecting 25 poisonous substances from among the organic solvents, pigments, and additives used in paint manufacturer, the GHS classification results by MOL and MOE were compared. Further the logic and classification of the GHS proposed by each Ministry was analyzed. Based on the derived results, a harmonization plan was proposed. Results: Based on the GHS classification of the poisonous substances, the concordance is 10.0-66.6 %, excluded flammable liquid. The GHS classifications differed based on the suggested building blocks, the sub-classification method used, the references(data sources), and subjective judgment of the experts from each Ministry. In order to pursue the harmonization plan, cooperation is demanded from the MOL and MOE.

• Toxicological Research
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• v.17
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• pp.41-45
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• 2001

The methods used for risk assessment from exposure to chemicals are well established. in most cases where toxicity other than carcinogenesis is being considered, the standard method relies on establishing the No Observed Adverse Effect Level (NOAEL) in the most sensitive animal toxicity study and using an appropriate safety factor (SF) to determine the exposure which would be associated with an acceptable risk. For carcinogens a different approach is used because it has been argued there is no threshold of effect. Thus mathematical equations are used to extrapolate from the high doses used in ani-mal experiments. These methods have been strongly criticised in recent years on several grounds. The most cogent criticisms are a) the equations are not based on a thorough understanding of the mechanisms of carcinogenesis and b) the outcome of a risk assessment based on such models varies more as a consequence of changes to the assumptions and equation used than it does from the data derived from carcinogenicity experiments. Other criticisms include the absence of any measure of the variance on the risk assessment and the selection of default values that are very conservative. Recent advances in the application of risk assessment emphasise that measures of both the exposure and the hazard should be considered as a distribution of values. The outcome of such a risk assessment provides an estimate of the distribution of the risks.

• Environmental Analysis Health and Toxicology
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• v.30 no.sup
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• pp.4.1-4.7
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• 2015

Objectives Approximately 2000 phase-in substances are subject to registration according to the Act on the Registration and Evaluation, etc. of Chemical Substances (K-REACH), and the expected testing cost is 2.06 trillion Korean won assuming all the test data required for registration are acquired. The extent to which these enormous test costs can be reduced depends on the availability of existing data that can be used to meet the requirements of the K-REACH we examined the current availability of test data that can be used for chemical substance registration. Methods We analyzed the possibility of utilizing the existing test data obtained from 16 reference databases for 369 of 518 kinds of phase-in substances subject to registration that were reported in last October 2014. Results The physical and chemical properties were available for 57.1% of substances, whereas data regarding human hazards and environmental hazards were available at considerably lower rates, 8.5% and 11.8%, respectively. Conclusions Physical and chemical properties were available for a fairly high proportion, whereas human hazards and environmental hazards were reported for considerably fewer substances.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.9
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• pp.4185-4197
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• 2016

Chronic arsenicosis is a major environmental health hazard throughout the world, including India. Animals and human beings are affected due to drinking of arsenic contaminated ground water, due to natural mineral deposits, arsenical pesticides or improperly disposed arsenical chemicals. Arsenic causes cancer with production of free radicals and reactive oxygen species (ROS) that are neutralized by an elaborate antioxidant defense system consisting of enzymes and numerous non-enzymatic antioxidants. Dietary antioxidant supplements are useful to counteract the carcinogenesis effects of arsenic. Oyster mushroom lectins can be regarded as ingredients of popular foods with biopharmaceutical properties. A variety of compounds have been isolated from mushrooms, which include polysaccharides and polysaccharopeptides with immune-enhancing effects. Lectins are beneficial in reducing arsenic toxicity due to anticarcinogenetic roles and may have therapeutic application in people suffering from chronic exposure to arsenic from natural sources, a global problem that is especially relevant to millions of people on the Indian subcontinent.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.04a
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• pp.128-131
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• 2003

It is well known that the membrane separation process combined with surfactant micelle (micellar-enhanced ultrafiltration) or polyelectrolyte (polyelectrolyte-enhanced ultrafiltration) can remove heavy metals effectively. However, the environmental hazard of surfactant or polyelectrolyte remained in effluent is a serious disadvantage of these methods. In this study, humic substances (HS) were used as complexing agents for metal removal instead of synthetic chemicals. The HS are a sort of natural organic matters which are biodegradable and abundant in natural environment. And the functional groups such as carboxyl groups and phenols in HS can bind with the cationic radionuclides and form complexes. Therefore separation process using them will be more environmental-friendly. The effects of concentration of HS and pH on the removal of cobalt were investigated. The ultrafiltration process was applied to the separation of the cobalt - HS complexes from the aqueous stream. At the concentration of > 3 g/L of HS and pH of 6, over 95 % of cobalt was removed by regenerated cellulose membrane of molecular weight cut-off (MWCO) 3,000. As the concentration of HS increased, the removal of cobalt also was improved because of increase in biding sites (functional groups). The cobalt removal increased from 72.5 % to 97.5 % when pH increased from 4 to 8 at the concentration of 3 g/L HS because of increase in HS solubility and cobalt hydroxide precipitation. In the presence of NaCl, the removal efficiency of cobalt decreased.

• Journal of the Korean Ceramic Society
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• v.37 no.8
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• pp.760-767
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• 2000

Recently, the protection of construction is demanded with environmental pollution. These protect modes are use of concrete admixture, coat of protective polymer and impregnate of surface with chemicals etc. The most widely used impregnation is economical and effective. The define of Impregnation for construction protect is reacted in and consolidated substrate after absorbed. The impregnation agents are Polyesters, Acrylic monomers, Epoxy and Silicone derivatives. Commonly, because the Silane has good water repellency and environmental advantages that it widely used to water proofing agents, dampproofing agents and absorption reducer for concrete of bridges. When application of Silane, it occurs pollution and harmfulness as included organic solvent. The manufactures have tired to emulsification of Silane for the reducing of the defects. The Silane emulsion is vary unstable and does not stored long periods, and it is diminished in good properties with internal reaction. In this study we tried to emulsification of Silane for effectiveness improvement and reduce pollution and hazard and discussed properties variation of emulsion. The Silane emulsions are achieved emulsifying with W/O and O/W type surfactants. It used 0.24% PVA as protective colloid and stable phase is creamy. The creamy Silane emulsion performance as the penetration depth and water absorption rate are above 4 mm and below 0.1. It stable about 6 month at room temperature.

• Journal of the Korean Society of Safety
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• v.16 no.2
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• pp.75-79
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• 2001

For handling and storage of reactive chemicals, the hazard evaluations have been extremely important. In the chemical industry, the most concerns are focused on the thermal harzards such as runaway reactions and thermal decompositions, which are mostly governed by thermodynamics and reaction kinetics or these reactive chemical in the system. This study no investigated the thermal decomposition characteristics of nitrophenylhydrazine isomers by using differential scanning calorimeter(DSC) and accelerating rate calorimeter(ARC). Experimental results showed that exothermic onset-temperatures in nitrophenylhydrazine(NPH) isomers were about 160-$210^{\circ}C$ by DSC and 100-$150^{\circ}C$ by ARC. The decomposition temperature acquired by ARC was about 50-$60^{\circ}C$ lower than that by DSC. Reaction heats were about 40-100cal/g by DSC and 330-750ca1/g by ARC. While ortho isomer of NPH show two distinct exothermic peaks, para isomer shows a single peak in DSC curves. The first exothermic peak for 2-NPH is mainly due to intramolecular dehydration forming 1-hydroxybenzotriazole(HOBT) and the second exothermic peak is mainly due to the decomposition of HOBT formed in the first step of decomposition. The exothermin peak in the DSC curve for 4-NPH is mainly due to dissociation of hydrazino and nitro groups.

• Safety and Health at Work
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• v.6 no.4
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• pp.345-352
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• 2015

Background: Goal-oriented communication of risk of hazards is necessary in order to reduce risk of workers' exposure to chemicals. Adequate training of workers and enterprise priority setting are essential elements. Cleaning enterprises have many challenges and the existing paradigms influence the risk levels of these enterprises. Methods: Information on organization and enterprises' prioritization in training programs was gathered from cleaning enterprises. A measure of enterprises' conceptual level of importance of chemical health hazards and a model for working out the risk index (RI) indicating enterprises' conceptual risk level was established and used to categorize the enterprises. Results: In 72.3% of cases, training takes place concurrently with task performances and in 67.4% experienced workers conduct the trainings. There is disparity between employers' opinion on competence level of the workers and reality. Lower conceptual level of importance was observed for cleaning enterprises of different sizes compared with regional safety delegates and occupational hygienists. Risk index values show no difference in risk level between small and large enterprises. Conclusion: Training of cleaning workers lacks the prerequisite for suitability and effectiveness to counter risks of chemical health hazards. There is dereliction of duty by management in the sector resulting in a lack of competence among the cleaning workers. Instituting acceptable easily attainable safety competence level for cleaners will conduce to risk reduction, and enforcement of attainment of the competence level would be a positive step.