Although concerns about Arsenic (As) contamination in agricultural foods have currently increased, there in on adequate international risk management standards for As particularly on agricultural commodities and processed agricultural products. This scenario holds true also in Korea. Australia, and New Zealand has determined the As maximum level (ML) but only on cereals grains which is based on total As contents. In addition,Japan has regulated the ML based on trivalent As contents in agricultural commodities, which do not have legal restrictions. On the other hand, China has developed a systemic risk management to restrict the As contamination above MLs in agricultural commodities and processed agricultural products based on inorganic and total As contents. The establishment of an adequate analytical method for As specification in agricultural foods is essential to determine the acceptable level of As in agricultural food. Probabilistic approach may remove some uncertainties in calculating human risk assessment from As. It should be reviewed in terms of maximum levels to set the best scenario based on a realiability and availability to achieve effective As management on agricultural foods in Korea.

The reduction rate of pesticide residues on spinach(bifenthrin, metalaxyl, procymidone), chard(bifenthrin, imidacloprid) and mallow(bifenthrin, chlorpyrifos, imidacloprid) were tested on each step of washing and boiling(spinach: 1, 3, 5min., chard: 3, 6, 9min., mallow: 10, 20, 30min.). The reduction rates of bifenthrin and procymidone by washing were 58~64% and 82%, and these were not changed significantly after boiling. In case of imidacloprid, the rates showed 43% on chard and 12% on mallow by washing, and these were highly increased to 94% after boiling. And the reduction rate of metalaxyl and chloropyrifos were 69% and 11% by washing, and 96~98% and 77~79% by boiling. Specifically we monitored the pesticide residues on both boiled vegetable and its water because there are used to cook as soup in Korea. The total residual amounts of imidacloprid and chloropyrifos were effectively removed on both boiled mallow and its water (12% → 34~40%, 11% → 76~79%), however, the other tested pesticides were not changed on pesticide residues when calculated with total amounts on boiled vegetable and its water. These explained the other pesticides were just moved vegetable to water by boiling.

Analytical method using capillary GC/ECD was developed to determine trace residues of chlorfluazuron, 1-[3, 5-dichloro-5-trifluoromethyl-2-pyridyloxy)phenyl)-3-(2, 6-difluorobenwyl), in meat, and applied to analyze the residues in domestic and imported meats. The analytical scheme developed does not require column chromatographic cleanup; chlorfluazuron was extracted with diethyl ether and petroleum ether (50: 50), partitioned against acetonitrile, cleaned up with silica Sep-Pak cartridge, identified GC/ECD, and comfirmed by GC/MS. The mean recoveries of the pesticide in meat fortified with standard solution 0.1, 0.5, 1.0 mg/kg were ranged from 82 to 95%. The limit of detection and limit of quantitation were 0.001 and 0.005 mg/kg, respectively. Chlorfluazuron residues were not found in domestic samples, but found in imported Australian beef ranging from 0.02 to 0.17 mg/kg, detected by 18% among the samples.

The simultaneous analysis of multi-residual pesticides was developed using a gas chromatography (GC) method. In this study, a simple and reliable methodology was improved to detect 154 kinds of pesticides in ginseng extract sample by using a liquid-liquid extraction procedure, open column chromagraphy and chromatographic analysis by GC electron capture detector (ECD) and GC nitrogen-phosphorus detector (NPD). The 154 kinds of pesticides were classified in 4 groups according to the chemical structure. The extraction of pesticides was experimented with 70% acetone and dichloromethane/petroleum ether in order, and cleaned up via open column chromatography (3×30㎝) packed with florisil (30g, 130℃, 12hrs). The final extract was concentrated in a rotator evaporator at 40℃ until dryness. Then the residue was redissolved to 2㎖ with acetone, and analyzed by GC-ECD and GC-NPD. The applied concentration of pesticides was over 1~10㎍/㎖. The recovery tests were ranged from 70.7% to 115.2% with standard deviations between 0.3 and 5.7% of the standard spiked to the ginseng extract sample (Group Ⅰ~Ⅳ). The limit of detection (LOD) ranged from 0.001 to 0.099㎍/㎖ (Group Ⅰ~Ⅳ). The 9 kinds of pesticides were not detected. The developed method was applied satisfactory to the determination of the 154 kinds of pesticides in the ginseng extract with good reproducibility and accuracy.