• 한국환경과학회지
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• 제8권1호
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• pp.19-26
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• 1999

The degree of pesticides accumulation in tap water in Taejon from June 1995 to Apr 1996 was measured by Ellman's coupled enzyme assay. Since organic phosphate and carbamate pesticides specifically inhibit the neurotransmitter modulating enzyme acetylcholinesterase(AChE), the enzyme activity can be used as a diagnosis for the pesticides accumulation in water and various samples. During the period of this study, the enzyme activity was changed almost every week. The lowest enzyme activity was 64 % of that of the control reaction and there are several days showing about 100 % enzyme activity. In general, the enzyme activity is higher in summer than other seasons especially early spring times. The pH value of tap water was very close to neutral(pH 7.0) and it seems that the enzyme activity was not affected by the small pH changes. Either boiling of tap water or addition of NaOH solution decomposed the pesticide components. These results show that AChE assay is a convenient, sensitive, and reliable method for detection of pesticides in water samples.

• 한국식품위생안전성학회지
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• 제17권2호
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• pp.87-93
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• 2002

김치의 주재료인 배추에 사용되는 농약중 3종의 유기인계 살충제를 배추에 처리하여 수세, 소금절임 그리고 김치 숙성과정 및 가열조리 후의 잔류농약의 변화정도를 조사하였다. 흐르는 물에 배추를 씻어 농약의 잔류량을 측정한 결과 pirimiphos-methyl의 경우 62.0%, chlorpyrifos 54.8% 그리고 prothiofos는 61.1%가 제거되었고 배추를 소금에 절이는 과정중에서도 각각 23.5%, 22.4%그리고 23.8%가 제거되었다. 4。C에서 김치를 숙성하는 과정중 농약의 잔류량은 24일의 숙성기간동안 pirimiphos-methyl 69.4%, chlorpyrifos 66.6% 그리고 prothiofos 51.4% 정도가 제거되었다 이때 김치의 pH는 김치를 담근지 7일이 경과하고 난 이후부터 감소하기 시작하여 24일이 경과되었을 때는 pH가 4.5까지 감소되었다. Chlorpyrifos가 잔류하는 김치를 4。C, 10。C그리고 20。C에서 11일간 숙성시키면서 숙성온도에 따른 chlorpyrifos의 잔류량의 변화를 조사한 결과, 각각의 숙성온도에 따라 29.2%, 45.0%그리고 77.3%가 제거되어 숙성온도가 높을수록 제거율은 높은 것으로 나타났다. 김치를 가열 조리하는 과정중 chlorpyrifos의 잔류량은 가열 조리후 16.3%정도 제거되었다.

• 농약과학회지
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• 제16권1호
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• pp.11-20
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• 2012

식량증산을 위해 농약사용량이 증가함에 따라, 식품 중 잔류농약의 안전성 문제에 대한 관심은 날로 증가하고 있지만 효율적인 잔류농약 저감화 방법은 보급되지 못하고 있는 것이 현실이다. 최근에 기체 플라즈마에 의한 오염물질 제거는 고효율성과 환경친화성으로 많은 주목을 받고 있다. 특히 플라즈마는 수질 및 고체 표면 중 유기인계살충제, 페놀, 벤조산, 염료, 니트로벤젠과 같은 오염물질의 제거에 큰 효과가 있는 것으로 알려지고 있다. 본 연구는 플라즈마를 이용하여 농식품 중에 잔류되는 농약의 제거 가능성을 알아보고자 대기압 및 감압플라즈마 플라즈마 발생 상태에서 60종의 농약을 대상으로 분해양상을 파악해보고자 시도하였다. 시험용 농약을 유리판에 도포 후 대기압 및 감압 플라즈마 발생기에서 5분간 조사 후 잔류량을 확인 한 결과 대조구의 회수 분석결과가 70% 미만인 18종을 제외한 41종의 농약 분해율이 66.88-100%를 나타내었고, clothianidin은 감압플라즈마하에서 26.9%이 분해율을 보였다.

• 농약과학회지
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• 제9권1호
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• pp.41-50
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• 2005

본 연구에서는 인삼성분의 조성을 변화시키지 않으면서 잔류농약만 제거시키는 방법을 pilot plant system에서 확립하고자 하였으며, 원래의 제조 공정에 따라 제조한 제품과 농약제거 공정을 적용하여 제조한 제품에서 155종의 잔류농약성분을 모니터링하였으며, 인삼성분을 비교 검토하였다. 농약제거공정을 거친 4가지의 공정은 control test에 비하여 잔류농약의 양이 많이 감소하였다. 즉, hexane을 이용한 공정에서 잔류농약이 제거되었고, 농약의 제거율을 높일 수 있는 가장 효율적인 방법은 헥산침지후 건조과정을 거친 공정으로 나타났다. 개발된 방법은 인삼농축액의 성분에는 영향을 미치지 않고 잔류농약만 89.1% 제거할 수 있었다.

• Journal of Ecology and Environment
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• 제41권11호
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• pp.318-327
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• 2017

Background: A typical sewage treatment plant is designed for organic and nutrient removal from municipal sewage water and not targeted to eliminate micropollutants such as pesticides, pharmaceuticals, and nano-sized metals which become a big concern for sustainable human and ecological system and are mainly discharged from sewage treatment plant. Therefore, despite contaminant removal by wastewater treatment processes, there are still remaining environmental risks by untreated pollutants in STP (sewage treatment plant) effluents. This study performed aquatic toxicity tests of raw wastewater and treated effluents in two sewage treatment plants to evaluate toxicity reduction by wastewater treatment process and analyze concentration of contaminants to reveal potential toxic factors in STP effluents. Methods: Water samples were collected from each treatment steps of two STPs, and acute and chronic toxicity tests were conducted following USEPA (United States Environmental Protection Agency) and OECD (Organization for Economic Cooperation and Development) guidelines. Endpoints were immobility for mortality and reproduction effect for estrogenicity. Results: Acute $EC_{50}s$ (median effective concentration) of influents for Seungki (SK) and Jungnang (JN) STPs are $54.13{\pm}32.64%$ and $30.38{\pm}24.96%$, respectively, and reduced to $96.49{\pm}7.84%$ and 100%. Acute toxicity reduction was clearly correlated with SS (suspended solids) concentration because of filter feeding characteristics of test organisms. Chronic toxicity tests revealed that lethal effect was reduced and low concentration of influents showed higher number of neonates. However, toxicity reduction was not related to nutrient removal. Fecundity effect positively increased in treated wastewater compared to that in raw wastewater, and no significant differences were observed compared to the control group in JN final effluent implying potential effects of estrogenic compounds in the STP effluents. Conclusions: Conventional wastewater treatment process reduced some organics and nutritional compounds from wastewater, and it results in toxicity reduction in lethal effect and positive reproductive effect but not showing correlation. Unknown estrogenic compounds could be a reason causing the increase of brood size. This study suggests that pharmaceutical residues and nanoparticles in STP effluents are one of the major micropollutants and underline as one of estrogenic effect factors.

• 한국환경농학회지
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• 제39권3호
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• pp.246-252
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• 2020

BACKGROUND: Pesticides are broadly used to control weeds and pests, and the residues remaining in crops are managed in accordance with the MRLs (maximum residue limits). Therefore, an analytical method is required to quantify the residues, and we conducted a series of analyses to select and validate the quick and simple analytical method for tolpyralate in five agricultural products using QuEChERS (quick, easy, cheap, effective, rugged and safe) method and LC-MS/MS (liquid chromatography-tandem mass spectrometry). METHODS AND RESULTS: The agricultural samples were extracted with acetonitrile followed by addition of anhydrous magnesium sulfate, sodium chloride, disodium hydrogencitrate sesquihydrate and trisodium citrate dihydrate. After shaking and centrifugation, purification was performed with d-SPE (dispersive-solid phase extraction) sorbents. To validate the optimized method, its selectivity, linearity, LOD (limit of detection), LOQ (limit of quantitation), accuracy, repeatability, and reproducibility from the inter-laboratory analyses were considered. LOQ of the analytical method was 0.01 mg/kg at five agricultural products and the linearity of matrix-matched calibration were good at seven concentration levels, from 0.0025 to 0.25 mg/L (R²≥0.9980). Mean recoveries at three spiking levels (n=5) were in the range of 85.2~112.4% with associated relative standard deviation values less than 6.2%, and the coefficient of variation between the two laboratories was also below 13%. All optimized results were validated according to the criteria ranges requested in the Codex Alimentarius Commission (CAC) and Ministry of Food and Drug Safety (MFDS) guidelines. CONCLUSION: In conclusion, we suggest that the selected and validated method could serve as a basic data for detecting tolpyralate residue in imported and domestic agricultural products.

• 한국토양비료학회지
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• 제34권3호
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• pp.185-191
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• 2001

호남지역 농경지에 수년간 사용되어 온 타로닐, 만코지, 벤타존 및 부타클로르약제에 대한 내성균의 밀도를 조사하고 이들 내성균주를 분리하여 미생물속의 분포 및 타로닐의 분해정도를 검토한 결과는 다음과 같다. 호남지역 농경지에 분포한 타로닐을 비롯한 4개약제 $500{\mu}g\;ml^{-1}$에 생존하는 내성균의 밀도는 $10^3cfu\;g^{-1}$이 상으로 시설재배지> 밭> 논토양 순으로 높았고, 약제별로는 벤타존> 부타클로르> 타로닐> 만코지 순으로 높았으며, 이들4개 약제 $500{\mu}g\;ml^{-1}$에서 분리된 내성균주의균속 분포율은 Acinetobacter속과 Corynebacterium속이 높게 나타났으나 Moraxella속은 낮게 나타났다. 타로닐 연용 밭토양에 $0{\sim}100{\mu}g\;g^{-1}$까지 처리후 20일간 배양시 사상균수는 초기보다 감소하였으나 호기성3, 방선균 및 타로닐내성균수는 크게 증가하였고, 멸균 토양중에서 다코닐약제 분해균주의 밀도는 $10{\mu}g\;g^{-1}$처리시 접종후 5일경에 가장 높았고, TD-25균주는 TC-23균주보다 높은 밀도로 나타났다. 다코닐 약제처리후 20일째의 약제잔류농도는 고농도처리에서 높았고 약제분해는 TD-25균주> 무멸균토양 함유균주> TC-23균주 순으로 나타났다.