Levels of 2,4-D Residues in Marketed Citrus Fruits and Juices Collected from Eastern Taiwan Area

JIIN-FUNG SHYU AND JASON DALANG HONG

National Laboratories of Foods and Drugs, Department of Health, Executive Yuan. 161-2, Kuen Yang Street, Nan Kang, Taipei, Taiwan, R.O.C.

ABSTRACT

   An assay method for 2,4-D residues in citrus fruits and juices was developed to evaluate the levels in marketed products collected from the eastern Taiwan area. The method was modified slightly from the standard method established by Department of Health, R.O.C.. Citrus samples were extracted with solvents, which was removed by evaporation with a rotary evaporator under reduced pressure. The concentration of 2,4-D residue was then quantified with GC after methylation in the presence of sulfuric acid. A total of 25 grapefruits and 15 grapefruit juices, 25 citrus and 15 citrus juices, and 20 lemons and 15 lemon juices were sampled and analysed. Among all the samples analysed only two lemon samples were detected to have low level of 2,4-D residues (0.28 and 0.42 ppm). No significant amout of 2,4-D residues was found in all other samples.

Key words : 2,4-D, citrus fruits, citrus fruit juices