| Pesticide residues in edible agro-products are concerned as the most important issues of food safety. With cucumber as the major research material, the status of pesticide residues in cucumber production in China was reviewed in this paper. Following the principles of hazard analysis and critical control points (HACCP), critical control points of pesticide hazards in cucumber production were analyzed. Techniques for evaluation of pesticide risk index and effects of pesticide dosages were further developed. Technology for monitoring pesticide application and a framework system for process control of pesticides application in cucumber production were also established. The major issues from the relevant research and further application of the established technologies were discussed in the paper and results were summarized as follows:1. Two pesticide control systems, harmless cucumber production and green cucumber production, were analyzed. Besides, all operations of a representative farmer in a season were recorded, and investigation of pesticide use reality was done in Shandong and Beijing. Results showed that, many problems existed in pesticide control system in cucumber production: few indices were set for control of pesticides in soil and water in producing field; the operation requirement was not clear and systematic, without control strategies of each single pest; basic production conditions of pesticide hazard control were not good because of impractical pesticide safety indices, random use of pesticides, unconsciousness of pesticide safety; there were few standards of pesticide tolerances and testing techniques which were practical in production; monitoring system was incomplete, and there was no surveillance during production; and structure proportion of registered pesticides in China was irrational. Carbendazim and thiophate-methyl contamination in soil and cucumber is popular in Shandong and Beijing, with the highest total residue 1.982 mg/kg in soil and 0.696 mg/kg in cucumber.2. In-field pesticide concentration prediction and risk indices evaluation model (IFPCPRIEM) were built based on scientific data. Concentration of soil remain, leaching, drift, residues in plant and residues on plant were predicted through adopting sorption equation, first-class degradation equilibrium and combining pesticide chemical, physical, toxicological parameters with soil and environmental parameters. Among all the evaluated pesticides, twenty nine of them such as copper hydroxide etc. have high soil residue concentrations above 0.01 mg/kg; and eight pesticides such as thiamethoxam have high leaching concentrations beyond 0.1 ug/L. Environmental risk index and human risk index were obtained according to predicted concentrations to calculate pesticide actual total index in registered application rate. According to the study, risk indices of abamectin,beta-cypermethrin,chlorpyrifos,isoprocarb are from 50 to 500. Among fungicides, risk indices of copper sulfate, maneb, fenaminosulf etc were beyond 1.0. For pesticides to be applied in soil, risk indices of hymexazol, quintozene were as high as 3.496,4.962 separately. Comparation of predicted concentrations with testing residue result in cucumber showed that the diviation rate is below 20%. So, pesticide risk index evaluation technology is correct and trustworthy in some degree. 3. Criteria system of pesticide control in cucumber production was recommended according to pesticide risk index evaluation. Thirty one registered pesticides were selected for control cucumber pest because their risk indices were below 1.0. Then, application times (not beyond five times) of them in each season were recommended. And the preharvest interval (PHI) and maximum residue limits (MRL) were set based on pesticide residue dynamic changes in cucumber. Pesticide effect assessment proved that in reference doses, dimethomorph,cymoxanil,diethofencarb,chlorothalonil,flusilazole,kresoxim-methyl,thiram,acetamiprid,imidacloprid,alpha-cypermethrin,pirimicarb,cyromazine could control target pests well. Techniques of testing dimethmorph by gas chromatography (GC) and testing cymaxnil by gel permeable chromatography (GPC) and high performance liquid chromatography (HPLC) were studied. Combined with analysis of other pesticides, the test system was set for the ten pesticides. Pesticide safe operation procedures (SOPs) were composed of operations in pesticide selection, applicator training, label, application rate calculations, loADIng and mixing, application and personal protection. What's more, to strengthen pesticide control, the monitoring method were proposed including regional planning, making big vegetable production farm a model for minor farm, pesticide user certification and record keeping, and pesticide use inspection.4. Hazard analysis (HA) for pesticide control system in our country is conducted to showed that the main pesticide hazard in cucumber production is caused by organophosphorous, organochlorine insecticides and trADItional fungicides such as carbendazim, mancozeb, iprodine. Through HA, four critical control points in cucumber production were confirmed including field selection, soil treatment, fumigant treatment in greenhouse, and pest chemical control. The framework of process control system for pesticides in cucumber production in our country was built to control hazards of pesticides used for cucumber downy mildew (Pseudoperonospora cubensis), grey mold (Botrytis cinera), powdery mildew (Erysiphe cichoracearum and Sphaerotheca fuliginea), Fusarium wilt (Fusarium solani), aphid (Aphis), leafminer (Liriomyza spp.), and whitefly (Trialeurodes vaporariorum). It included two models, integrated crop and pest management module (ICPMM) and pesticide control module (PCM). In ICPMM, detailed crop management and integrated pest management strategies were introduced. In PCM, the pesticide hazard control technologies were based on study of pesticide risk index evaluation, pesticide standards of maximum residue limit (MRL) and safe use operation, and monitoring system in forementioned chapters.Studies in the paper are theoretically helpful for pesticide hazard control in cucumber production, and act as a model for other vegetbale production. The framework establishment will promote the development of specialty of agricultural product safety.
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