• 분석과학
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• 제23권4호
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• pp.357-362
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• 2010

프탈레이트 가소제는 환경보건법의 환경유해인자로서 인체발암물질로 분류되어 있지는 않으나 경구, 경피, 흡입 등의 경로로 체내에 흡수되어 종양발생, 변이원성, 생식독성을 나타내는 물질로 알려져 있어, 일부 국가에서는 어린이 용품 중 사용을 금지하는 물질이다. 따라서 본 연구에서는 어린이 제품에 함유된 프탈레이트류 8종에 대한 함유량 및 전이량 분석방법을 정립하고자 국내 및 미국, 일본, 유럽연합 등 국외 어린이용품에 관련된 인체 전이율 분석방법을 파악하고, 기존 연구에서 제시된 시험방법을 비교, 검토하였으며, 이를 토대로 표준화된 시험방법을 제안하였다. 또한 어린이용품에 함유된 프탈레이트의 최종 노출량을 산정하기 위해 제안된 시험방법에 따라 함유량과 전이량을 분석하고 그 상관관계를 파악하였으나 상관성이 없는 것으로 조사되었다.

• Journal of Microbiology and Biotechnology
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• 제18권11호
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• pp.1826-1835
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• 2008

An autotrophic denitrification reactor (ADR-l) and a heterotrophic denitrification reactor (HDR-2) were operated to remove nitrate and nitrite in an anoxic environment in raw sewage. The $NO_3$-N removal rate of ADR-l was shown to range from 52.8% to 78.7%, which was higher than the $NO_3$-N removal rate of HDR-2. Specific denitrification rates (SDNR) of ADR-l and HDR-2 were 3.0 to 4.0 and 1.1 to $1.2\;mgNO_3$-N/gVSS/h, respectively. From results of restriction fragment length polymorphism (RFLP) of the 16S rRNA gene, Aquaspirillum metamorphum, Alcaligenes defragrans, and Azoarcus sp. were $\beta$-Proteobacteria that are affiliated with denitritying bacteria in the ADR-l. Specifically, Thiobacillus denitrificans was detected as an autotrophic denitrification bacteria. In HDR-2, the $\beta$-Proteobacteria such as Denitritying-Fe-oxidizing bacteria, Alcaligenes defragrans, Acidovorax sp., Azoarcus denitrificans, and Aquaspirillum metamorphum were the main bacteria related to denitrifying bacteria. The $\beta$-and $\alpha$-Proteobacteria were the important bacterial groups in ADR-l, whereas the $\beta$-Proteobacteria were the main bacterial group in HDR-2 based on results of fluorescent in situ hybridization (FISH). The number of Thiobacillus denitrificans increased in ADR-l during the operation period but not in HRD-2. Overall, the data presented here demonstrate that many heterotrophic denitritying bacteria coexisted with autotrophic denitrifying bacteria such as Thiobacillus denitrificans for nitrate removal in ADR-l. On the other hand, only heterotrophic denitritying bacteria were identified as dominant bacterial groups in HDR-2. Our research may provide a foundation for the complete nitrate removal in raw sewage of low-COD concentration under anoxic condition without any external organic carbon or the requirement of post-treatment.

• Journal of Preventive Medicine and Public Health
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• 제45권6호
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• pp.353-363
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• 2012

Methylmercury is a hazardous substance that is of interest with regard to environmental health, as inorganic mercury circulating in the general environment is dissolved into freshwater and seawater, condensed through the food chain, ingested by humans, and consequently affects human health. Recently, there has been much interest and discussion regarding the toxicity of methylmercury, the correlation with fish and shellfish intake, and methods of long-term management of the human health effects of methylmercury. What effects chronic exposure to a low concentration of methylmercury has on human health remains controversial. Although the possibility of methylmercury poisoning the heart and blood vessel system, the reproductive system, and the immune system is continuously raised and discussed, and the carcinogenicity of methylmercury is also under discussion, a clear conclusion regarding the human health effects according to exposure level has not yet been drawn. The Joint FAO/WHO Expert Committee on Food Additives proposed to prepare additional fish and shellfish intake recommendations for consumers based on the quantified evaluation of the hazardousness of methylmercury contained in fish and shellfish, methylmercury management in the Korea has not yet caught up with this international trend. Currently, the methylmercury exposure level of Koreans is known to be very high. The starting point of methylmercury exposure management is inorganic mercury in the general environment, but food intake through methylation is the main exposure source. Along with efforts to reduce mercury in the general environment, food intake management should be undertaken to reduce the human exposure to methylmercury in Korea.

• 환경정책연구
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• 제13권2호
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• pp.65-98
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• 2014

해양환경의 플라스틱은 풍화작용에 의해 매우 작은 크기로 부서지는데, 이를 미세플라스틱이라고 한다. 해수에 오염된 잔류성이 크거나 생물축적성이 있는 유기물질은 미세플라스틱에 잘 흡착되며, 이들 물질이 흡착된 미세플라스틱을 해양생물이 섭취하면 먹이사슬을 통해 점차 생물축적된다. 이는 결국 해양생태계의 건강성을 파괴하고 사람을 포함한 상위포식자에게 피해를 끼친다. 해양 오염물질의 흡착제로서의 역할뿐 아니라, 미세플라스틱 그 자체에서 내분비계 교란물질이 용출되어 해양생물에 피해를 입히기도 한다. 우리나라는 잔류성이나 생물축적성이 큰 물질에 대해서는 화학물질 측면에서 규제하고 있으나, 이는 육상에서의 관리에 국한되어 있다. 만약 이들 물질이 해양생태계로 유입되면, 결국 미세플라스틱 흡착 여부에 의해 그 피해가 증가하게 된다. 이에 해양생태계 내에서의 잔류성 생물축적성 물질의 피해를 저감하기 위해서는 우선 미세플라스틱의 관리가 엄격해야 할 것이다. 이에 미세플라스틱 자체를 유해물질로 지정하여 엄격히 관리하거나, 생분해성 플라스틱 이용 확대, 재활용 및 재사용 촉구, clean-up 프로그램의 확대 등을 통해 해양생태계 내로의 플라스틱 유입을 저감하는 노력이 요구된다.

• 한국산업보건학회지
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• 제23권1호
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• pp.27-34
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• 2013

Objectives: The purpose of this study is to calculate the worker-DNEL (Derived No Effect Level) values using the REACH guidance and compare the calculated DNELs with existing Korea occupational exposure limits (KOELs) for evaluation of the applicability of the worker-DNELs as provisional occupational exposure limits for chemicals that are not established KOELs in the workplace. Methods: The worker-DNELs for 46 chemicals among 113 hazardous substance requiring management were calculated using the REACH guidance, and a paired t-test was performed to see if there is any statistical difference between two lists (worker-DNELs vs KOELs). The ratios of KOELs over worker-DNELs were also calculated to compare the overall levels of two lists using the geometric means method. Results: The calculated worker-DNELs for 46 chemicals ranged from 0.001 to $329mg/m^3$ (GM= 6.9, GSD = 10.8), and appeared to be a significant difference between the worker-DNELs and the KOELs (p < 0.01). In addition, the ratios of KOELs over worker-DNELs ranged from 0.3 to 394 times (GM = 10.2, GSD = 3.9), indicating that the worker-DNELs were, on average, 27 times lower than the KOELs. Conclusions: Therefore, the study results show that the calculated worker-DNELs can be applied and used as provisional occupational exposure limits in the workplace in order to reduce worker exposures to chemicals and health risks, and manage potential worker exposures based on the precautionary principle through comprehensive chemical risk assessment.

• 한국환경보건학회지
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• 제47권2호
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• pp.144-154
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• 2021

Objectives: This study was intended to identify hazard contribution by region, media, and chemical by calculating a hazard-based index using pollutant release and transfer register (PRTR) data. Methods: PRTR data for the period 2011 to 2016 was analyzed to examine the regional trends in toxic releases in terms of quantity and to create a corresponding hazard-based index. For the hazard-based index, the Risk-Screening Environmental Indicators (RSEI) Model was used. Results: The results of the trend analysis show that total releases decreased slightly, but health hazard levels increased consistently. According to the outcome of regional contribution analysis of the hazard-based index, Chungcheongnam-do, Jeollabuk-do and Gyeonggi-do Provinces showed a high ratio in the index for air and water release pollutants, while Gyeongsangbuk-do and Gyeongsangnam-do Provinces showed a high ratio in the index of soil release and waste transfer pollutants. Also, as a result of the analysis of the top ranked substances in the hazard-based index, it was found that chromium, cobalt and its compounds, and ethylene oxide contributed greatly to air release substances, while chromium, benzene, and lead and its compounds contributed greatly to water release substances. Conclusion: These results showed considerable disparities between total release and health hazard levels, especially in the analysis of contribution by regions and by chemical substance. Therefore, the hazard-based index should be used both to support a more comprehensive and robust approach to screening of chemicals for environmental health policy and for management.

• 한국환경보건학회지
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• 제47권2호
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• pp.166-174
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• 2021

Objectives: This study aimed to provide temporal Acute Exposure Guideline Levels (AEGL) for a hazardous substance as a pilot study. Methods: As one of the substances designated by the Korea Ministry of Environment as requiring preparations for potential accidents, formaldehyde was selected to estimate the AEGLs. The calculation was based on Haber's formula (Cn×t=k) using valid toxicity data (for humans/animals). A total of 96 points of AEGL levels were provided using an interval of five minutes over eight hours. Results: The AEGL-1 and 2 values were constant for the entire exposure duration at 0.9 ppm and 14 ppm, respectively. The values were obtained from clinical/animal tests, and the adaptation effect after a given exposure duration was also considered. AEGL-3 was based on animal toxicity data, and it was estimated from 127 ppm for the initial five minutes to 35 ppm for eight hours. Conclusions: More specific AEGL levels for formaldehyde could be obtained in this study using toxicity data with Haber's formula. Based on this methodology, it would be also possible to estimate AEGL levels that can be used at the scene of a chemical accident for other substances requiring preparation for potential accidents.

• 센서학회지
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• 제31권2호
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• pp.90-95
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• 2022

The effect of the structure of an ITO nanoparticle film sensor on its performance was studied. A printed ITO film (P-ITO film) was fabricated on a flexible polyethylene terephthalate (PET) substrate, and the contact resistance of the electrode and sensor response change were clarified according to the detection position. The contact resistance between Ag and P-ITO was observed to be -204.4 Ω using the transmission line method (TLM), confirming that a very good ohmic contact is possible. In addition, we confirmed that the contact position of the analyte had a significant influence on the response of the sensor. Based on these results, the performance of the four types of sensors was compared. Consequently, we observed that 1) optimizing the resistance of the printed film, 2) optimizing the electrode structure and analyte input position, and 3) optimizing the electrode area are very important for fabricating a metal oxide nanoparticle (MONP) sensor with optimal performance.

• 한국환경보건학회지
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• 제48권3호
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• pp.183-194
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• 2022

Background: No study has examined the regulatory factors associated with fatal health problems due to the use of humidified disinfectants (HD) in South Korea. Objectives: This study aimed to identify and discuss the deficiencies and limitations found in the Toxic Chemical Control Acts (TCCA) that failed to prevent the health risk of chemicals in HD products. Methods: The South Korean TCCA was reviewed focusing on acts in operation from 1994 through the end of 2011, the period when HD was allowed in manufacturing and marketing. Results: The TCCA was the act intended to regulate the toxicity of chemicals in HD products. We found the TCCA to lack three key legal clauses which would have been essential to controlling the health risk of HD. First, there was the exemption of toxic and hazard testing for existing chemicals, including chloromethylisothiazolinone (CMIT), methylisothiazolinone (MIT), and benzalkonium chloride (BKC). Secondly, there were no articles requiring industry to provide animal inhalation test result for polymers such as polyhexamethylene guanidine (PHMG) and Oligo(2-)ethoxyethoxyethyl guanidine chloride (PGH). Finally, there was a lack of articles on examining the risk of products as well as on addressing changes in the usage of products. These articles were found to be generally provided in the US Toxic Substance Chemical Act (TSCA) and the EU Registration, Evaluation and Authorization of Chemicals (REACH). Conclusions: In conclusion, the Ministry of Environment of South Korea had not updated key articles for regulating hazardous chemicals, causing large-scale health problems due to HD which had been fundamentally addressed in chemical-related acts in other countries.

• 분석과학
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• 제21권6호
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• pp.526-534
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• 2008

가축의 생산성 향상을 위해 투여될 수 있는 천연호르몬과 합성 호르몬제 등의 내분비계장애물질에 대하여 기존의 분석 방법을 개선 및 확립하고, 이를 토대로 국내에 유통 중인 육류 및 내장부위 중소간에 대해 호르몬 성분의 분포정도를 확인하였다. Estrogens ($17{\beta}$-estradiol, $17{\alpha}$-estradiol, estrone), androgens ($17{\beta}$-testosterone, $17{\alpha}$-testosterone), gestagens (progesterone)의 천연호르몬 6종과 합성호르몬 3종 DES, RALs (zeranol, taleranol)을 모니터링 대상 호르몬으로 GC-MS로 분석하였으며, 이로부터 호르몬의 background level을 측정하고, 상대적으로 호르몬제 등이 잔류될 수 있는 간 등의 장기에 대한 분포조사를 실시하였다. 전체 150건의 시료 중 합성 호르몬제는 검출되지 않았으며, 천연호르몬제는 내인성으로 존재하는 progesterone이 일반적인 농도 범위를 보였다.