1. Abstract:
Onions, as one of the main food, constantly attacked by pests and diseases,
including onion thrips, flies, red root rot and fungal and bacterial infections has
been. The most important pestof onions, thrips Thripstabaci Lindeman is now in
most parts of our country, especially in Isfahan to fight this pest, from Insecticide
Profenofos used. According to widespread often indiscriminate use of pesticides in
the province, the Residue of cultivated onions are very important. It seems
especially considering Pre-Harvest period by some farmers and agricultural
producers are not considered.
Profenofos for determining residues of liquid - liquid extraction was used. After
sampling the onion fields, the samples after extraction and gas chromatography GC
and GC / MS and HPLC measurements were also methods of extraction, solid
phase extraction (SPE) and solid phase microextraction (SPME) as In order to
compare with the liquid - liquid extraction was tested.
Results indicated that 33 percent of the total sample was contaminated That 27%
of samples reached limit contamination of as CodexMRL have been stated by
committee. Average percentage recovery of liquid - liquid extraction, 117 percent
and 90.5 percent were evaluated. Average percent recovery solid phase extraction
(SPE), 39.5 percent and the average percent recovery was obtained with Solid
Phase Microextraction method (SPME) with variable recovery of 40.8 and 106
percent.
Investigation showed that the liquid - liquid of solvent consumption, short time
and speed are not affordable But in terms of efficiency can also detected
Profenofos the Onion and the qualitative and quantitative measurements using gas
chromatography to demonstrate their advantage . Therefore, the accuracy in
measuring the efficiency of pesticides used to ensure the data is especially
important.
Keywords:
Onion, Residue , Profenofos , Liquid - Liquid Extraction (LLE) , Solid Phase
Microextraction (SPME) , Solid Phase Extraction (SPE)