사과 중 triazole계 살균제 flusilazole 및 myclobutanil의 생물 학적 반감기와 출하전 잔류허용기준을 산출하기 위해 안 전사용기준에 근거한 기준량과 3배량의 약제를 살포하고 그 잔류량을 조사하였다. 시험기간 중 두 농약의 잔류량은 각각의 MRL 이하로 나타났으며, 사과 중 생물학적 반감기 는 flusilazole의 경우 기준량 처리구에서 6.7일, 3배량 처리 구에서 6.2일로 나타났다. 반면에 myclobutanil의 반감기는 기준량 처리구에서 13.3일, 3배량 처리구에서 24.8일로 나 타나 flusilazole보다 더 긴 반감기를 가지는 것으로 조사되 었다. First order kinetics에 근거한 감소지수식을 이용하여 산출된 각 농약의 감소상수는 flusilazole에 대하여 0.0513, myclobutanil에 대하여 0.0244이었으며, 산출된 감소상수들 을 이용하여 출하 전 잔류허용기준(PHRL)을 계산한 결과, 안전사용기준을 준수한 농약살포를 가정하였을 때 flusilazole은 수확 일주일 전 0.43 mg/kg, myclobutanil은 같은 시기 0.59 mg/kg 이하로 잔류하면 수확 시 잔류농도가 MRL 이하로 잔류할 것으로 예측된다.

약용식물 중 잔류농약의 안전성을 평가하고자 2012년 전국 9개 도시에서 유통되고 있는 인삼과 도라지에 대하여 전체 112점의 시료를 수거하여 잔류농약을 분석하였다. 122 종의 농약에 대해 GC-ECD, GC-NPD 및 HPLC-UVD를 이용한 다종농약 다성분 분석법으로 잔류농약을 분석하였고, 분석 결과 12점의 시료에서 7종의 농약이 검출되어 10.7% 검출률을 보였다. 농약 성분별 검출 빈도는 procymidone, kresoxim-methyl, endosulfan, cypermethrin, tralomethrin, tetraconazole, chlorfluazuron 순이었다. 농약 이 검출된 시료 중 잔류허용기준을 초과한 시료는 2점으 로 1.8% 검출률을 보였으며, 도라지 1점에서 tetraconazole, 인삼 1점에서 cypermethrin이 검출되었다. 해당 작물에 대한 잔류허용기준이 설정되어 있지 않거나 품목고시 되어 있지 않은 시료는 10점에서 5종의 농약이 검출되어 8.9% 검출률을 보였다. 본 연구에서 검출된 농약이 해당 약용 식물의 섭취로 인체에 유입될 일일섭취허용량 대비 일일 섭취추정량은 최저 0.006%에서 최고 0.333%로 낮은 %ADI 값을 보여 인체 위해도는 낮은 것으로 판단되었다.

본 연구에서는 위해요소관리 중심의 사과 GAP 모델 개발을 위한 기초자료를 제공하기 위해 경남에 소재한 GAP 미인증 사과농장 3곳을 선정하여 재배단계에서 화학적(중금속), 생물학적 위해요소(위생지표세균, 병원성 미생물, 곰팡이)를 분석하였다. 화학적 위해요소인 중금속은 재배환경 중 토양에서만 국내 허용치 이하 수준으 로 Cu, Pb, Zn 및 Ni이 검출되었다. 생물학적 위해요소의 경우 일반세균과 대장균군은 재배환경에서 각각 0.8~6.1과 0.0~5.0 log CFU/g(or mL), 사과와 잎에서 0.4~3.6과 0.0~3.5 log CFU/g(or leaf), 개인위생에 서 3.2~5.3과 0.4~2.7 log CFU/hand(or 100 cm2) 수준으로 검출되었고, 대장균은 모든 시료에서 검출되지 않았다. 병원성 미생물은 S. aureus가 작업자의 손에서 최대 4.4 log CFU/hand 수준으로 검출되었고, B. cereus는 사과를 제외한 모든 시료에서 0.0~5.2 log CFU/g(or leaf, mL, hand or 100 cm2) 범위로 검출되었 으며, L. monocytogenes, E. coli O157:H7 및 Salmonella spp.는 검출되지 않았다. 곰팡이는 모든 시료에서 0.0~4.9 log CFU/ g(or leaf, mL, hand or 100 cm2) 수준으로 검출되었다. 이상의 결과는 안전한 사과를 생 산하기 위한 위해요소관리 중심의 사과 GAP 모델 개발에 있어 재배환경 및 재배단계에서의 위해요소를 파악하 고 분석하는데 필요한 기초자료로 활용될 수 있을 것으로 판단된다.

Currently there is a great increase in concern about the safety of food we eat and the potential hazards arising from contamination with synthetic pesticide residues on crops. In general, consumers tend to believe that synthetic pesticides and there residues in crops are dangerous to our health. On the other hand, less attention has been paid to the naturally occurring toxic substances in crops, which may cause or contribute to illness in humans. The Korean peninsula is very hot and humid during the summer season. This environment is good for the growth of various kinds of pests and pathogens as well as crops. Therefore, Korea has been one of the most intensive pesticide consuming countries of the world, an attractive market for multinational pesticide companies. In order to control the diseases, pests and weeds effectively, the use of pesticides in agriculture is inevitable. The pesticides protect the reduction of production from diseases, insect pests and weeds. Furthermore, they provide the stable food and crop supply by improving the quality. Thus, the pesticides are the most economical and safe substance to replace and cover the shortage of rural work force, which gets more and more serious. Pesticide industry in Korea has just a short history of 50 years. Taking the procedures of the import, adoption and imitation of the foreign technologies, five compounds were synthesized newly by our technology and registered as insecticide, fungicide and herbicide. Until now the most of pesticide technicals were imported from foreign countries with high price. The imported technicals are formulating with adjuvant in manufacture factory. From the 1970s a part of technicals which is expired patent are synthesizing by our own technology. Totally of 1,230 items has been notified to be used as pesticide by the government at 2008. The pesticide production in 2008 was 21,168 M/T as an active ingredient. The amount was divided 17.5% for paddy rice, 45.4% for horticultural plants, 26.2% for weed and 10.9% for others. By formulation, emulsifiable concentrate is 46.3%, wettable powder 32.6%, granule 17.5%, dust 0.8% and water soluble powder 0.7%. The total amount of imported pesticide was 443,362 thousand dollars. Among them the technical grade is 77.4%, intermediates for synthesis 4.1%, formulation 18.5%. The technical grade was divided with fungicides 28.7%, insecticides 34.2%, herbicides 26.2% and others 10.9%. The major importing countries are Japan 29%, Germany 15.2%, United State 15%, China 12.6%, Swiss 8.4% and others 29%. The local production ratio of technicals is 10.6% of the required technicals in Korea. On the other hand, Korea is exporting some technical grade and formulations to several nations. The agrochemical market value of Korea in 2008 was 27,586 thousand dollars. The ideal pesticide would be toxic only to the target organism, but unfortunately this cannot often be achieved and most pesticides are to some extent hazardous to other organisms also and, therefore, potentially harmful to those handling them. At present 2008, the maximum residue limit (MRL) for 399 pesticides was established in all crops. And the standard for safe use for 800 items except herbicides was also established in each crop. Every year, Korean government is monitoring the residue level of pesticides to agricultural products for safety of consumers. The classification of pesticides toxicity by the Pesticides Management Law is based primarily on its acute oral and dermal toxicity to test animals. This hazard classification of Korea is following the method of WHO. The hazard class is divided into 4 groups; extremely hazardous, highly hazardous, moderately hazardous and lowly hazardous. Among 1,230 items including 28 items of biopesticide using in Korea, there is no extremely hazardous group, 17 items in highly hazardous group, 175 moderately hazardous and 1,038 lowly hazardous. Apart from classification system by acute toxicity, to minimize the side effects caused by pesticides we have another system prescribing definitely the enforcement degree of crop-residual, soil-residual and water-residual pesticides. Crop-residual pesticide is legally defined as the agrochemical that its terminal residue level in crop harvests exceeds the national maximum residue limit. The residual pesticide of which its persistence is evaluated to have longer than 180 days of half life in soil and the residual impacts on the second cropping is recognized, donates as the soil-residual pesticide. And both of crop and soil residual pesticides are prohibited to register for use. Water residual pesticide of which the fish toxicity (TLm, 48hrs) to the carp is less than 0.1ppm is also legally regulated and banned for use in paddy field. What kinds of pesticides are required for the future of Korean agriculture? Everybody will reply. "They must have the high activity, be safe and without harmful effects to the animals and environment". But actually the development of ideal pesticides in Korea is very difficult owing to invest of lots of money and time. So we are using the technology of molecular design for toxicity reduction of already existing pesticides, and research for development of biopesticides by the bioengineering technique using plants and microorganism. To use pesticides effectively, we have to research and evaluate of integrated control measures including development of biological, enzyme and hormone manipulation, and mechanical controls resulting in pest management concepts. For the future, it is necessary to produce and use more effective and more selective pesticides. Over the development of synthetic pesticides from 1940s there have been significant changes in the tools available for research and development of pesticides. Research on pesticides has gone from spray and prays to high throughput screening on in vitro targets. Analytical techniques of pesticides now allow easier identification of metabolites and degradation products, whilst parts per trillion can be routinely determined. These changes have been largely driven by advances in computing power over the past decades. Similarly, the modeling for development of new pesticides that can now be carried out would have seemed impossible 50 years ago. Information today is also much more readily accessible than before, the internet is a tool which has come of age and is the repository of a large amount of information. Communications have similarly changed with personal mail allowing instant communication with fellow scientists. In the future, international cooperation will be more needed for the exchange of related and updated information in safety evaluation and development of pesticides.

Sweet potato whitefly Bemisia tabaci is a serious pest of various economically important crops. For the control of B. tabaci in an environment-friendly way, we demonstrated the effect of azadirachtin, which is an active conpound of neem oil as an botanical insecticide, on the development of B. tabaci by using an assay of single tomato leaf. Egg hatch rates were 53.6, 50.3% at 5 and 10 ppm, respectively. Adult eclosion rates were 30.0, 22.9% at these doses. We determined the whitefly control efficacies of two application methods of neem-based products by comparing between a direct spray of liquid-type into leaves and a soil treatment of pellet-type. Soil treatment of neem was greatly inhibited adult colonization by 75%. Those plants also inhibited the rates of oviposition and larval development. However, single treatment of foliar spray of neem (5-10 ppm) did not significantly inhibit the initial colonization of adult whiteflies. Furthermore, adult colonization was gradually increased regardless of neem spray.