Development of Methods to Determine Pesticide Residues in TEA Using HPLC and GC-MS

Abstract

Tea (Camellia sinensis) is the second most popular beverage in the world. Only water is rated higher in world consumption than tea. Sri Lankan tea is popular through out the world due to its taste and quality. A limited number of insecticides, matricides, fungicides and weedicides are applied in tea fields depending on the incidence of pests, diseases or weeds. Application of these pesticides leaves traces on the tea leaves and remains in the processed tea. These are called as pesticide residues The export marker of tea is facing huge problem about its quality. Because some time pesticide residues are present in some tea lots. It causes damage to the good will of the Ceylon tea in the export market. This research was aimed to examine the pesticides residues in export tea (2 ,4-D and Glyphosate), before releasing to the export market. During the research period, try to develop the extraction methods for extract to Glyphosate and 2,4-D from the tea leaves. There are several steps involved such as sampling,extraction, extract clean up, concentration, separation of extract compounds, detection and confirmation of identity. High performance liquid chromatography machine was used to analyzed Glyphosate and Gas chromatography Mass spectrometry was used to analyzed 2,4-D. Results indicated that, qualitatively and quantitatively satisfied extraction method for 2.4-D and qualitatively satisfied extraction method for Glyphosate. Recovery percentage was nearly 88.77% and minimum detection limit was O.Olppm for 2.4-D.Inaddition extraction methods should be developed for Glyphosate to satisfied quantitative test.