The Unseen Threat: Microplastic Emissions from Face Masks and Limited Public Awareness

Park Yeonjung,Bae Heekyung,Park Ha-neul,Park Jeonggue,홍재환,Kim Younghun 한국화학공학회 2024 Korean Journal of Chemical Engineering Vol.41 No.1

Masks are typically made of plastic materials, which can contribute to plastic pollution if not properly disposed. A survey should be conducted to assess the public awareness of microplastics (MP) emissions and mask disposal, which could inform targeted educational campaigns to promote sustainable practices. This study used an online survey to gather data from a sample of the general public aged 20 years or older who had used masks. The survey included questions on mask usage, disposal, and awareness of the presence of MP in masks. The survey found that, although awareness of the risks of MP was high, the respondents’ understanding of them was low, particularly among younger individuals. The survey also revealed that more than half of the respondents did not know whether their masks contained plastic materials and that there was a lack of awareness regarding the potential environmental and health impacts of improper mask disposal. These results revealed that it is crucial to raise public awareness of the environmental and health impacts of improper mask disposal and the presence of MP in masks.

Evaluation of the energy efficiency of combined drying and heat treatment by superheated steam

Park, Yonggun,Han, Yeonjung,Park, Jun-Ho,Chang, Yoon-Seong,Yang, Sang-Yun,Chung, Hyunwoo,Yeo, Hwanmyeong Taylor Francis 2017 Drying Technology Vol.35 No.12

The effectiveness of Paxlovid treatment in long-term care facilities in South Korea during the outbreak of the Omicron variant of SARS-CoV-2

Park Hanul,Park Young Joon,Lee Hye Young,Yu Mi,Song Yeong-Jun,Lee Sang Eun,Lee Ji-Joo,Lee Eun-Sol,Kim Yeonjung 질병관리본부 2022 Osong Public Health and Research Persptectives Vol.13 No.6

Objectives: On November 5, 2021, Pfizer Inc. announced Paxlovid (nirmatrelvir+ritonavir) as a treatment method that could reduce the risk of hospitalization or death for patients with confirmed coronavirus disease 2019 (COVID-19).Methods: From February 6, 2022 to April 2, 2022, the incidence of COVID-19 and the effects of treatment with Paxlovid were analyzed in 2,241 patients and workers at 5 long-term care facilities during the outbreak of the Omicron variant of severe acute respiratory syndrome coronavirus 2 in South Korea.Results: The rate of severe illness or death in the group given Paxlovid was 51% lower than that of the non-Paxlovid group (adjusted risk ratio [aRR], 0.49; 95% confidence interval [CI], 0.24−0.98). Compared to unvaccinated patients, patients who had completed 3 doses of the vaccine had a 71% reduced rate of severe illness or death (aRR, 0.29; 95% CI, 0.13−0.64) and a 65% reduced death rate (aRR, 0.35; 95% CI, 0.15−0.79).Conclusion: Patients given Paxlovid showed a lower rate of severe illness or death and a lower fatality rate than those who did not receive Paxlovid. Patients who received 3 doses of the vaccine had a lower rate of severe illness or death and a lower fatality rate than the unvaccinated group.

Public behavior and awareness of mask litter as microplastic source

Yeonjung Park,Heekyung Bae,Hyunwook Kim,Jeonggue Park 환경독성보건학회 2023 한국독성학회 심포지움 및 학술발표회 Vol.2023 No.11

Evaluation of Deterioration of Larix kaempferi Wood Heat-treated by Superheated Steam through Field Decay Test for 12 Months(12개월 야외 내후성 시험에 의한 과열증기 열처리된 낙엽송재의 열화 평가)

( Yonggun Park ),( Yeonjung Han ),( Jun-ho Park ),( Hyunwoo Chung ),( Hyunbin Kim ) 한국목재공학회 2018 목재공학 Vol.46 No.5

본 연구에서는 과열증기를 이용하여 열처리한 낙엽송재의 야외 내후성 시험을 통해 부후균과 해충에 대한 저항성을 평가하였다. 12개월간 진행된 야외 내후성 시험 결과, 무처리재는 흰개미에 의한 피해가 두드러지게 나타났지만 방부목재와 과열증기 열처리재에서는 육안으로 관찰되는 피해는 발견되지 않았다. 무처리재와 방부목재는 약 5%의 질량 감소를 보였으며, 과열증기 열처리재는 약 1%의 질량 감소를 보였다. 야외 내후성 시험이 진행된 후 방부목재에 남아있는 방부약제의 함량이 야외 내후성 시험 전보다 감소한 것으로 보아 야외 내후성 시험이 진행되는 동안 방부약제가 일부 용출된 것으로 보이며, 이에 따라 방부목재의 질량 감소가 무처리재와 유사한 수준으로 나타난 것으로 생각되었다. 과열증기를 이용한 열처리는 방부약제 주입과 같은 화학적인 처리 없이 친환경적으로 목재의 부후균과 해충에 대한 저항성을 개선시킬 수 있는 가능성이 확인되었으며, 이를 위하여 장기적인 관찰이 추가적으로 필요할 것이라 생각된다. In this study, the decay resistance of larch wood, which was heat treated by superheated steam, was evaluated by the field decay test. During the field decay test of 12 months, non-treated wood has been severely damaged by termite, however, no visible damage has occurred in the preservative-treated wood and superheated steam heat-treated wood. Results of field decay test showed approximately 5% mass loss of the non-treated wood and the preservative-treated wood, and approximately 1% mass loss of the superheated steam heat-treated wood. After the field decay test for 12 months, the residual amount of preservatives remaining in the preservative-treated wood was lower than that before the field decay test. It was considered that the preservative was partially eluted during the field decay test, and the mass loss of the preservative-treated wood was thought to be similar to that of the non-treated wood. Through this study and additional long-term monitoring test, superheated steam heat treatment can be considered to be an environmental-friendly method to enhance the decay resistance of wood against rot fungi and/or insect without chemical treatment such as preservative injection.

중국 태권도장의 서비스 품질과 행동의도 간 분석

박연정 ( Park Yeonjung ),이병찬 ( Lee Byungchan ) 대한체육학회(구 한국유산소운동과학회) 2021 대한스포츠융합학회지 (jcses) Vol.19 No.1

The purpose of this analysis was to verify the relationship between Taekwondo centre service quality and behavioral intention. To achieve the goal, a total of 272 questionnaires were distributed to Taekwondo centre in Sichuan, China. Conducted frequency analysis, exploratory factor analysis, reliability verification, correlation analysis and multiple regression analysis by utilizing SPSS 24.0 ver. The results are as follows. First, programme and human resources factor of Taekwondo centre had effected on re-visit intention of behavioral intention. However physical environment of Taekwondo centre service quality had no effect on re-visit intention. Second, physical environment and programme factor of Taekwondo service quality had effected on oral intention of behavioral intention.

고온 열기 처리에 의한 낙엽송재의 물리,역학적 성능 및 내부후성능 변화 고찰

박용건 ( Yonggun Park ),한연중 ( Yeonjung Han ),박준호 ( Jun Ho Park ),장윤성 ( Yoon Seong Chang ),양상윤 ( Sang Yun Yang ),정현우 ( Hyunwoo Chung ),김경중 ( Kyungjung Kim ),여환명 ( Hwanmyeong Yeo ) 한국목재공학회 2015 목재공학 Vol.43 No.3

본 연구에서는 국내에서 상업적으로 이용되고 있는 국산 낙엽송 열처리재의 여러 가지 물성(밀도, 평형함수율, 수축률, 흡습/흡수성, 종/횡압축강도, 휨강도, 경도, 내부후성능)을 정량적으로 평가하기 위하여 수행되었다. 고온처리에 의해 목재의 소수성이 증가함에 따라 평형함수율이 감소하였다. 이에 따라 수축률 및 흡습/흡수성이 감소하여 치수안정성이 개선되었고, 낮은 함수율의 영향으로 압축강도가 증가하였으며, 목재 주성분의 변화와 낮은 함수율의 영향으로 내부후성능이 개선되었다. 하지만 열처리에 의해 밀도와 휨강도 및 경도는 감소하였다. This study was carried out to evaluate quantitatively some properties (density, equilibrium moisture content, shrinkage, water vapor adsorption, water absorptivity, compressive strength, bending strength, hardness and decay resistance) of Larix kaempferi lumber which was heat-treated by hot air and has been used commercially in Korea. Equilibrium moisture content of the heat-treated wood was decreased with increase of hydrophobicity. Dimensional stability of the wood was improved with decrease of shrinkage, water vapor adsorption and free water absorptivity. Also, with the thermo-chemical changes of wood component and lower equilibrium moisture content, decay resistance and

과열증기 열처리 낙엽송재의 물리?역학적 성능 및 내후성능 평가

박용건 ( Yonggun Park ),박준호 ( Jun-ho Park ),양상윤 ( Sang-yun Yang ),정현우 ( Hyunwoo Chung ),김현빈 ( Hyunbin Kim ),한연중 ( Yeonjung Han ),장윤성 ( Yoon-seong Chang ),김경중 ( Kyoungjung Kim ),여환명 ( Hwanmyeong Yeo ) 한국목재공학회 2016 목재공학 Vol.44 No.5

본 연구에서는 pilot scale에서 과열증기를 이용하여 실대재 낙엽송 생재 각재를 열처리하고, 열처리된 낙엽송재의 다양한 물리·역학적 성능과 내후성능을 측정하였다. 또한, 이를 고온 열기 열처리한 낙엽송재의 물성과 비교하였다. 생재로부터 할렬 발생이 억제된 상태로 과열증기 열처리된 낙엽송재의 갈색부후균과 백색부후균에 대한 저항성과 종압축강도는 증가한 반면에 밀도와 평형함수율 및 수축률과 휨강도는 관행 열처리재보다 낮게 측정되었다. 과열증기목재 열처리는 다량의 수분에 의해 열전달이 빠르고 열가수분해가 촉진되기 때문에 유사한 시간과 온도에서 열기를 이용하여 관행 열처리한 경우보다 열처리 효과가 높게 나타났다. 따라서 과열증기 열처리 방법은 생재를 할렬 없이 열처리할 수 있으며, 관행 열처리 방법보다 낮은 온도 또는 짧은 열처리 시간으로도 동일한 열처리 효과를 발현시킬수 있다. 즉, 열처리에 소요되는 시간과 에너지를 줄일 수 있다. In this study, green Larix kaempferi lumber was heat-treated by using superheated steam (SHS) at a pilot scale and then various physico-mechanical properties of the heat-treated wood were evaluated and compared with the properties of conventional hot air (HA) heat-treated wood. Decay resistance of brown rot fungi and compressive strength parallel to the grain of the SHS heat treated wood without occurrence of drying check from green lumber were increased. On the other hand, density, equilibrium moisture content, shrinkage, and bending strength of the SHS heat-treated wood were lower than those of the conventional HA heat-treated wood. Because heat transfer and thermal hydrolysis of SHS heat treatment was accelerated by a large amount of water, the effect of SHS heat treatment on the physico-mechanical properties was higher than that of HA heat treatment at the similar conditions of temperature and time. From the results of this study, because green lumber can be heat-treated without occurrence of cracks or checks by using SHS and similar heat treatment effect on the physico-mechanical properties of wood can be produced despite a low temperature or short time of heat treatment, it is expected that heat time and energy consumption could be reduced by using SHS.

Potency classification of isothiazolinone compounds based on defined approaches of skin sensitization in OECD GL 497

Hyejin Kim,Juyoung Park,Handule Lee,Jinseon Son,Yeonjung Park,Heekyung Bae,Sun-Young Park,Sang Hee Lee,Jungkwan Seo,Sunkyung Shin,Kwangsik Park 환경독성보건학회 2023 환경독성보건학회지 Vol.38 No.4

Regulatory decisions for skin sensitization are now based on adverse outcome pathway (AOP) and integrated approaches to testing and assessment (IATA). Based on these, Organisation for Economic Co-operation and Development (OECD) guidelines on defined approaches for skin sensitization were adopted with a fixed data interpretation procedure (DIP). In the guidelines, “Defined Approaches” (DA) on skin sensitization uses the results from multiple information sources of in chemico, in vitro, and in silico data to achieve an equivalent predictive capacity as those of the animal tests. In this review, we evaluated the skin sensitization of eleven isothiazolinone compounds including 4,5-Dichloro-2-octyl-3(2H)-isothiazolone (DCOIT), 2-n-Octyl-4-isothiazolin-3-one (OIT), 2-Methyl-4-isothiazolin-3-one (MIT), 1,2-Benzisothiazolin-3-one (BIT), 1,2-Benzisothiazolin-3-one, 2-butyl (BBIT), 5-Chloro-2-methyl-4-isothiazolin-3-one (CMIT), 2-methyl-4,5-trimethylene-4-isothiazolin-3-one (MTMIT), 2-methyl-1,2-benzothiazol-3-one (MBIT), 2-methyl-1,2-benzothiazole-3-thione (MBIT-S), 1,2-benzisothiazolin-3-one, 2-methyl-, 1,1-dioxide (BBIT-O), and a mixture of CMIT/MIT. Data from direct peptide reactivity assay (DPRA), human cell line activation (h-CLAT) test, and quantitative structure activity relationship (QSAR) Toolbox were evaluated and were applied to the DIP to derive a prediction of hazard identification and a potency classification. Among the evaluated chemicals, six isothiazolinone compounds were classified to be UN GHS 1A, one compound to be UN GHS 1, and four compounds could not be classified due to lack of data. The results of sensitizer chemicals were found to coincide well with those of in vivo test.

Assessment of Hepatic Steatosis Improvement Using Controlled Attenuation Parameter in Patients with Non-Alcoholic Fatty Liver Disease under Regular Follow Up

( Kyu Sik Jung ),( Jun Yong Park ),( Mi Na Kim ),( Hana Park ),( Yun Bin Lee ),( Joo Ho Lee ),( Yeonjung Ha ),( Beom Kyung Kim ),( Seung Up Kim ),( Sang Hoon Ahn ),( Do Young Kim ),( Hana Park ),( Kyu 대한간학회 2017 춘·추계 학술대회 (KASL) Vol.2017 No.1

Aims: The change of hepatic steatosis in non-alcoholic fatty liver disease (NAFLD) patients under regular follow up has not been widely investigated. We investigated the serial changes of hepatic steatosis assessed by controlled attenuation parameter (CAP) and the predictors for improvement of hepatic steatosis in NAFLD patients. Methods: Among 513 NAFLD patients diagnosed upon ultrasound and CAP > 250 dB/m at baseline, 304 patients underwent repeated CAP measurement at baseline and at follow up. The improvement of hepatic steatosis was defined as a >10% decline of CAP value from the baseline. Results: Mean age of 304 patients was 58.8 ± 11.4 years and 80.1% were male. The mean CAP value significantly decreased from baseline to follow up (292.3 dB/m to 277.1 dB/m, P<0.001). During the median follow up of 15.3 (9.5-20.3) months, 34.5% patients showed improvement of hepatic steatosis. In a univariate analysis, low body mass index (BMI), low weight, low liver stiffness value, low triglyceride level, and low ALT at follow up were predictors for improvement of hepatic steatosis. In multivariate analyses, low weight (P=0.004; hazard ratio [HR],0.965; confidence interval [CI], 0.941-0.988) and low ALT (P=0.004; HR,0.971;CI, 0.951-0.990) at follow up, or low BMI (P=0.006; HR,0.881; CI, 0.805-0.964) and low ALT (P=0.004; HR,0.971; CI, 0.951-0.990) at follow up were the independent predictors. In patients with weight reduction more than 10% (n=22), CAP value significantly decreased (from 288.0 dB/m to 228.9dB/m, P<0.001). Conclusions: Weight reduction, and ALT decrease were independent predictors for improvement of hepatic steatosis. Long term effect of weight reduction on improvement of hepatic steatosis and fibrosis should be investigated further.