• 펄프종이기술
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• 제34권3호
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• pp.38-45
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• 2002

The effect of sequential oxidative-reductive bleaching on brightening of the MOWs is investigated. The improvement in brightnesses of MOWs is more effective in conventional PFAS bleaching than in P/T bleaching. There is no difference in the mechanical properties or the bleached pulps between PFAS and P/T sequences. Considering the brightness gains and bleaching chemicals cost, for the MOW A(Initial brightness: 68.3% ISO) containing 5％ ONP and 20% colored paper, the P/T bleaching is more economical than the PFAS bleaching. However for MOW B(initial brightness: 59.1％ ISO) containing 15% ONP and 35％ colored paper, there is no difference in the bleaching efficiency between PFAS and P/T bleaching.

• Clinical and Experimental Pediatrics
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• 제63권12호
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• pp.463-468
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• 2020

Pollen-food allergy syndrome (PFAS) is an immunoglobulin E-mediated immediate allergic reaction caused by cross-reactivity between pollen and the antigens of foods-such as fruits, vegetables, or nuts-in patients with pollen allergy. A 42.7% prevalence of PFAS in Korean pediatric patients with pollinosis was recently reported. PFAS is often called oral allergy syndrome because of mild symptoms such as itching, urticaria, and edema mainly in the lips, mouth, and pharynx that appear after food ingestion. However, reports of systemic reactions such as anaphylaxis have been increasing recently. This diversity in the degree of symptoms is related to the types of trigger foods and the characteristics of allergens, such as heat stability. When pediatric patients with pollen allergy are treated, attention should be paid to PFAS and an active effort should be made to diagnose it.

• 한국환경보건학회지
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• 제50권1호
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• pp.54-65
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• 2024

Background: There is growing international recognition of the need for improvements to national chemical management systems for hazardous chemicals. The European Union has recently introduced the concept of 'essential uses' as a new approach to the management hazardous chemicals by limiting their uses. Objectives: This paper examines the concept of essential uses in chemical management and how to apply it through a case study of essential use. This approach is distinct from the current chemical management system, but seeks to improve its potential benefits by effectively restricting or gradually decreasing the use of hazardous substances. Methods: The concept of essential uses was introduced by reviewing the Montreal Protocol on Substances that Deplete the Ozone Layer, Cousins's three essentiality categories applied to PFAS, restriction options assessed in the PFAS restriction proposal under REACH, and the California Safer Consumer Products regulations prioritizing 6PPD in motor vehicle tires. Based on these essential uses concepts for PFAS and 6PPD, uses of benzene were classified in accordance with the essential uses approach for products using benzene in South Korea. Results: The essential use concept is able to manage the restriction and authorization of substances of concern through essential uses and non-essential uses and the feasible substitution of uses and substances. Conclusions: If the concept and methodology of essential uses are clearly established, they can be expected to shift the national chemical management paradigm from regulating substances to limiting uses under the existing substance management system.

• Allergy, Asthma & Immunology Research
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• 제10권6호
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• pp.648-661
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• 2018

Purpose: Pollen-food allergy syndrome (PFAS) is an immunoglobulin E (IgE)-mediated allergy in pollinosis patients caused by raw fruits and vegetables and is the most common food allergy in adults. However, there has been no nationwide study on PFAS in Korea. In this study, we investigated the prevalence and clinical characteristics of PFAS in Korea. Methods: Twenty-two investigators participated in this study, in which patients with allergic rhinoconjunctivitis and/or bronchial asthma with pollen allergy were enrolled. The questionnaires included demographic characteristics, a list of fruits and vegetables, and clinical manifestations of food allergy. Pollen allergy was diagnosed by skin prick test and/or measurement of the serum level of specific IgE. Results: A total of 648 pollinosis patients were enrolled. The prevalence of PFAS was 41.7% (n = 270). PFAS patients exhibited cutaneous (43.0%), respiratory (20.0%), cardiovascular (3.7%) or neurologic symptoms (4.8%) in addition to oropharyngeal symptoms. Anaphylaxis was noted in 8.9% of the PFAS patients. Seventy types of foods were linked to PFAS; e.g., peach (48.5%), apple (46.7%), kiwi (30.4%), peanut (17.4%), plum (16.3%), chestnut (14.8%), pineapple (13.7%), walnut (14.1%), Korean melon (12.6%), tomato (11.9%), melon (11.5%) and apricot (10.7%). Korean foods such as taro/taro stem (8.9%), ginseong (8.2%), perilla leaf (4.4%), bellflower root (4.4%), crown daisy (3.0%), deodeok (3.3%), kudzu root (3.0%) and lotus root (2.6%) were also linked to PFAS. Conclusions: This was the first nationwide study of PFAS in Korea. The prevalence of PFAS was 41.7%, and 8.9% of the PFAS patients had anaphylaxis. These results will provide clinically useful information to physicians.

• Environmental Analysis Health and Toxicology
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• 제23권3호
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• pp.143-164
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• 2008

Concern about perfluorinated compounds (PFCs) is growing nationally as well as globally. PFCs could be considered emerging POPs due to their environmentally persistent, bioaccumulative, and potentially harmful properties. Moreover. perfluoroalkylates (PFAs) such as PFOS and PFOA are reported to experience long-range transport (LRT) to the Arctic in spite of their low volatility and strong solubility. The possible pathways contributing to LRT have been proposed but are still in debate in combination with unclear source definition and uncertain physico-chemical properties. The environmental fate of PFCs is more complicated because of the presence of precursors that are degraded to PFAs and are extremely different from their daughters, PFAs. in physico-chemical properties. To what extent and through what pathways are human and wildlife exposed is determined by the environmental fate and distribution of PFCs. To define uncertainties in fate and distribution thus is critical to prevent erroneous policy and/or determination related with exposure and risk reduction. This article aimed to review controversy and/or uncertain issues for the environmental fate and distribution of PFCs and to prospect research topics necessary to dissolve uncertainties.

• 자원ㆍ환경경제연구
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• 제31권4호
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• pp.777-799
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• 2022

본 연구는 지구온난화잠재력(GWP)이 매우 큰 냉매가스에 대한 EU의 최신 규제 강화 동향을 살펴보고 탄소중립에의 시사점을 도출하였다. EU집행위는 최근 F-가스 규정(Regulation)을 대폭 강화하는 개정안을 공개하였다. 본 연구는 개정안의 냉매 관련 주요 내용의 의미를 현행 규정과 비교해 제시하였다. 개정안의 주요 내용은 시장출시 허용 HFC 최대량 대폭 축소, HFC 할당 관련 규정 강화, 고GWP 냉매 사용 제품 및 장비의 시장출시 금지 대상 추가, 규제대상 F-가스 추가 및 기존 가스의 GWP 업데이트, 그 외에도 보다 촘촘해지고 강화된 규제설계등이다. EU의 이러한 움직임은 미국, 일본 등 선진국의 정책기조에 영향을 미칠 것이며, 우리나라의 정책도 더욱 강화될 것이다. 따라서 관련 산업계에서는 차세대 냉매가스로의 변경이 불가피한 상황이 될 것이다. 한편, 본 연구는 기존의 냉매 및 F-가스 관련 연구에서는 주목하지 않았던 과불화화합물(PFAS) 규제와 관련된 최신 정책 동향에 대해서도 분석하였다. 유럽 5개국의 추진하고 있는 PFAS의 REACH(EU의 화학물질 등록, 평가, 승인 및 제한 제도) 제한물질 등록이 이뤄지게 된다면, 냉매가스와 관련해서는 산업계에 매우 큰 파장을 불러일으킬 것이다. 또한, 냉매를 비롯한 F-가스 물질과 관련된 각국의 온실가스 감축 전략도 전면 재검토가 불가피해질 것이다.

• 한국수산과학회지
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• 제55권5호
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• pp.514-523
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• 2022

Concentrations of perfluoroalkyl substances (PFASs) were measured in seawater, sediment, and biota collected from Gunsan coast, Korea to investigate their occurrence, distribution, and risk of exposure to humans through seafood consumption. The total concentrations of PFASs in seawater, sediment, and biota ranged from 5.97 to 74.9 ng/L, 0.01 to 13.3 ng/g dry weight, and 0.02 to 5.73 ng/g wet weight, respectively. Predominant PFAS compounds differed across matrices, indicating that the distribution of PFASs in multiple environmental samples is governed by their carbon-chain length. The concentrations of PFASs in seawater were significantly negatively correlated with salinity (P<0.01), suggesting terrestrial input (including land-used PFASs) as the major source of PFAS contamination in coastal environments. The estimated daily intakes (EDIs) of perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) through seafood consumption were 0.05 and 0.06 ng/kg body weight/day, respectively. The EDIs of PFOA and PFOS measured in this study were lower those the proposed by the United States Environmental Protection Agency and Canada guidelines, indicating limited health risk for Korean population from PFASs through consumption of seafood from Gunsan coastal environment.

• 상하수도학회지
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• 제37권4호
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• pp.177-186
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• 2023

Perfluorooctanoic acid(PFOA) was one of widely used per- and poly substances(PFAS) in the industrial field and its concentration in the surface and groundwater was found with relatively high concentration compared to other PFAS. Since various processes have been introduced to remove the PFOA, adsorption using GAC is well known as a useful and effective process in water and wastewater treatment. Surface modification for GAC was carried out using Cu and Fe to enhance the adsorption capacity and four different adsorbents, such as GAC-Cu, GAC-Fe, GAC-Cu(OH)₂, GAC-Fe(OH)₃ were prepared and compared with GAC. According to SEM-EDS, the increase of Cu or Fe was confirmed after surface modification and higher weight was observed for Cu and Fe hydroxide(GAC-Cu(OH)₂ and GAC-Fe(OH)₃, respectively). BET analysis showed that the surface modification reduced specific surface area and total pore volumes. The highest removal efficiency(71.4%) was obtained in GAC-Cu which is improved by 17.9% whereas the use of Fe showed lower removal efficiency compared to GAC. PFOA removal was decreased with increase of solution pH indicating electrostatic interaction governs at low pH and its effect was decreased when the point of zero charges(pzc) was negatively increased with an increase of pH. The enhanced removal of PFOA was clearly observed in solution pH 7, confirming the Cu in the surface of GAC plays a role on the PFOA adsorption. The maximum uptake was calculated as 257 and 345 ㎍/g for GAC and GAC-Cu using Langmuir isotherm. 40% and 80% of removal were accomplished within 1 h and 48 h. According to R², only the linear pseudo-second-order(pso) kinetic model showed 0.98 whereas the others obtained less than 0.870.

• Environmental Analysis Health and Toxicology
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• 제25권2호
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• pp.153-159
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• 2010

Perfluorooctane sulfonic acid (PFOS) and Perfluorooctanoic acid (PFOA) are the principal chemicals known as perfluoroalkyl acids (PFAs). Despite the widespread use of these compounds, relatively little is known about their fate and effects. The purpose of this study was to determine the toxic effects of PFOS and PFOA on Daphnia magna. In the acute toxicity test, D. magna were exposed for 48 hours at concentrations of 0, 30, 45, 67.5, 101.25 and 151.88 mg/L PFOS, and 0, 100, 160, 225, 337.5 and 506.25 mg/L PFOA, respectively. In the case of chronic toxicity test, D. magna were exposed through water for 21 days at concentrations of 0, 0.375, 0.75, 1.5, 3 and 6 mg/L PFOS, and 0, 1.25, 2.5, 5, 10 and 20 mg/L PFOA, respectively. Acute toxicity was assessed on the basis of immobility, while chronic toxicity was assessed on the basis of fecundity. The acute toxicity test on PFOS and PFOA showed that the values of $EC_{50}$ were 50.90 mg/L and 253.47 mg/L, respectively. In the chronic test, fecundity was reduced significantly at 1.5 mg/L of PFOS and 10 mg/L of PFOA, respectively. These results indicated that PFOS is more toxic to zooplankton than PFOA, and both chemicals have some hazard demonstrates risk for acute or chronic toxicity to freshwater organism.

• Journal of Forest and Environmental Science
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• 제39권1호
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• pp.1-12
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• 2023

To understand the health conditions and growth patterns of forest estate for environmental resilience and climate change mitigation, assessment of structure and species diversity is paramount. This study aimed at assessing the structure, alpha, and beta diversities of tree species in three ecological zones in Taraba, Nigeria for management purposes. In recent time, no research has been reported on the structure and beta diversity of the study areas. A systematic sampling design was used for data collection. Five sample plots of 50×50 m were laid in each of the six natural forest areas. The result showed a mean DBH (42.5 cm) and a tree height (15.0 m) from the forests. The forests have a structure of an inverse "J-shape," which is typical of natural forests in the tropics. The southern Guinea savanna zone had the highest mean Shannon-Weiner diversity index (2.8). The least beta diversity index (0.02) was between Baissa and Jen Gininya forest areas. Baissa and Bakin Dutse Protected Forest Areas (PFAs) contained 76.5% of the tree species. There is a high chance of all tree species to be found in these 2 forest areas. Proximity to a location influences how similar two tree species are, according to the least beta diversity index (0.02) recorded. The Federal Government's method of management for the forest, known as Gashaka Gumti National Park, may be responsible for the high beta diversity index in the Montane ecozone. Therefore, it should be strongly encouraged to practice strict oversight of natural areas, as their contributions to reducing climate change in Taraba State, Nigeria, cannot be overstated.