Rapid and Easy Multiresidue Method for Determination of Pesticide Residues in Foods Using Gas or Liquid Chromatography– Tandem Mass Spectrometry

To obtain a high yield of food grains, many types of pesticides have been developed, which in turn has facilitated the prosperity of the human race and brought relief to farmers. After WWII, organophosphorus and organochlorine pesticides were extensively used worldwide. These early organophosphorus pesticides occasionally caused poisoning, while some organochlorine pesticides persisted in the environment. These facts served as a warning against an improvident use of pesticides and revealed that residual pesticides in crops should be monitored. Thus, national and local governments should monitor imported and regional foods as a policy. In Japan, all pesticides are regulated under a uniform limit (0.01 μg/g), except for a combination of foods and pesticides set under the maximum residue limits (MRLs) (Notification No. 497-499, November 29, 2005). This regulation does not require analysis of all the pesticides; however, it does necessitate pesticide residue analysis of commodities. Thus far, the chemical industry has developed more than 800 pesticides that belong to many classes such as insecticides, fungicides, nematocides, and herbicides. Each class has a different target point and physical properties and this diversity limits the coverage of a single analytical method. It is also impossible to monitor all the pesticides pertaining to one foodstuff using hundreds of methods. Thus, analytical institutes require fast and efficient multiresidue methods in order to maximize the coverage of their monitoring activities. For this reason, researchers have reported many multiresidue analytical methods (Cook, J., et al., 1999, Fillion, J., et al., 2000, Hirahara, Y., et al., 2006, Luke, M. A., et al., 1975, Ueno, E., et al., 2004). These methods were optimized to monitor multiple residues efficiently and are used routinely in quarantine stations and laboratories. Anastassiades et al. reported a rapid approach for the analysis of pesticide residues in fruits and vegetables, named QuEChERS (quick, easy, cheap, effective, rugged and safe) method in 2003 (Anastassiades, M., et al., 2003). The main focus of this report was to shorten the analytical process during extraction and cleanup without employing expensive instruments. The characteristic points of the method are as follows: (1) shaking extraction with acetonitrile in a disposable tube, (2) one step salting out and removal of water from the