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Vegetables are essential daily necessities of human beings, their safety as everyone focus of attention, because it is directly related to human health and safety. National specially formulated pesticide residues in vegetables health limits, so to establish a convenient, fast and accurate detection of pesticide residues in vegetables is very necessary. The main contents of this paper: the establishment of solid-phase extraction - gas chromatography detection of pesticide residues in vegetables 35 methods, in reference to the original experimental method based on the experimental conditions were optimized using simple sample pre-treatment methods, explore more Best successfully separated component chromatographic conditions to achieve the best separation results. And the method accuracy, precision validated to determine solid-phase extraction - gas chromatography detection of pesticide residues in vegetables 35 best experimental conditions. Randomly selected city different types of commercially available vegetables, using optimized solid-phase extraction - gas chromatography detection of pesticide residues, and the test results were analyzed statistically. Collecting a city in 2003 to 2009 a total of seven years of monitoring data for pesticide residues in vegetables epidemiological investigation and analysis. Through experimental study obtained the following results: 1, solid phase extraction - gas chromatography detection of pesticide residues in vegetables 35 samples of the best experimental conditions were extracted with acetonitrile, using solid phase extraction column to purify. Optimal chromatographic conditions: Mixed mark a column used was DB-1701, inlet temperature: 170 ℃, detector temperature: 260 ℃, the oven temperature program: 80 ℃, keep 1min, to 20 ℃ / min l to 160 ℃, keep 1min, with 2 ℃ / min rose to 170 ℃, keep 2min, to 5 ℃ / min rose to 185 ℃, keep 2min to 0.5 ℃ / min rose to 187 ℃, keep 2min, to 0.1 ℃ / min rose to 188 ℃, keep 2min, to 0.5 ℃ / min rose to 189 ℃, keep 10min, to 5 ℃ / min rose to 230 ℃, keep 12min. Carrier gas: hydrogen 2.5mL/min, air 150mL/min. Split ratio: 5.0; makeup: 30mL/min. Just mix the column labeled 2 is spb-1, inlet temperature: 270 ℃; detector temperature 280 ℃; Oven temperature: 150 ℃, keep 1min, to 30 ℃ / min rose to 245 ℃; carrier gas : Nitrogen; flow rate: 0.5mL/min, retention 13.4min; to 0.1mL/min2 rose 0.8mL/min, retention 6.1min; to 0.1mL/min2 rose 1.5mL/min, retention 1min. 2, solid phase extraction - gas chromatography simultaneous determination of 35 kinds of pesticide residues in vegetables. Experiments show that detection of large quantities of samples of vegetables is a simple, good separation, high precision, accurate features, reducing the detection time, which greatly improve the detection efficiency. Revision of standards for national health data and provides a reliable basis. 3, the use of solid-phase extraction - gas chromatography, 315 randomly selected city commercial pesticide residues in vegetables results: 315 samples in 207 samples of pesticide residues detected, the detection rate of 65.7%. Excessive pesticide detected in 24 samples, exceeded the rate of 7.6%. 35 pesticide residues detected, the detection 23, where 10 is no corresponding national limits; while pesticide residues detected in four detection rate of over 10%. The highest detection rate of pesticide residues is dicofol, reaching 16.8%, the rest of the detection rate is below 10%. Methamidophos is GB may not be detected in the specified project, this study found that methamidophos was detected in 2.2%. 4, a city in 2003 to 2009, seven years a commercially available pesticide residues in vegetables and epidemiological survey results: 1668 samples, pesticide residues, the average detection rate of 39.4%, exceeding the average rate of 11.3%, and the average group detection rate of 18.7%. Samples lowest detection rate of 12.9% in 2004, the highest of 91.4% for the 2009; exceeding the lowest rate for 2004 was 1.9%, the highest for 2007 of 16.8%; multi-component detection rate was the lowest in 2004 to 1.0%, the highest of 67.9% in 2009. Leafy vegetables, roots, fruits and edible vegetables, pesticide testing four average detection rates were 41.5%, 40.0%, 34.3% and 39.8%. Organophosphate, carbamate, pyrethroid and organochlorine pesticides in four categories, the average detection rate was 28.6%, 4.6%, 16.7% and 1.0%. 5, the detection rate represents the use of pesticides, vegetable safety standard rate is judged whether or not the target. Field sampling and epidemiological survey, a city of pesticide residues in vegetables sold exceeded the rate has been gradually controlled at a relatively safe level. In this paper, a city of pesticide residues in vegetables, field testing and epidemiological findings, make a few suggestions: ① enhance the rational use of pesticides in vegetable growers advocacy, education and guidance. ② The higher detection rate of vegetables and pesticide component focused monitoring and control. ③ regulate pesticide trading markets, strengthening pesticide production and circulation of supervision and management of non-vegetable growers use state regulations may not be detected pesticides in vegetables.
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