Investigation of residual pesticides in cucumbers offered in Tabriz

Abstract

Material and Methods: In this descriptive-analytical study, 16 samples of the greenhouse and garden cucumbers were randomly collected from the central fruit and Background: Today, food security is one of the most important issues for consumers. Although, the use of chemical pesticides are very effective in increasing the quality and quantity of agricultural products, but excessive use of pesticides, farmers' ignorance in using pesticides and non-observance of pre harvest interval (PHI), can lead to unsafety agricultural products and environmental pollution. The aim of this study was to determine the residual concentrations of organophosphate pesticides (OPPs) in the greenhouse and garden cucumbers. vegetable field of Tabriz in a period of 6 months (July to December) in 2018. In total, in 48 samples (without washing, with washing, with peeling) the residual levels of 16 OPPs (dichlorvos, Mevinphos, dimethovate, diazinon, disulfoton, methyl parathion, Fenitrothion, Parathion, malathion, Fenthion, Bromofos, chlorpyrofos, chlorophene Winfus, Profenofus, Ethion and Azinfus methyl) were determined. Pesticide residues were analyzed using gas chromatograph-mass spectrometer (GC-MS, Agilent-7890A). The pesticide extraction from the matrix was done following the modified QuEChERS method. The health risk assessment of pesticide residues in cucumber was also conducted for two age groups of adults and children. Finally, data analysis was performed using SPSS 26 software at a significance level of 0.05. Results and discussion: In total of samples of greenhouse cucumbers (unwashed, washed and peeled), at least three pesticide residues (dimethoate, diazinon and methyl parathion) were detected and 92% of the samples contained more than three pesticides residues. In total of samples of garden cucumbers (unwashed, washed and peeled), at least two pesticide residues (dimethoate, diazinon were detected and 75% of the samples contained more than two pesticides residues. Of the 16 OPPs, the pesticide residues of dimethite, diazinon, profenofus, ethion and azinfus methyl were detected in both samples of greenhouse and garden cucumbers. Also, the pesticides residues of fenitrothion, methyl parathion and chlorpyrofos only in samples of greenhouse cucumber and pesticide residues of malathion only in samples of garden cucumber were identified. The average residue of pesticide after washing and peeling process were decreased in greenhouse cucumber samples 44.45% and 78.88% and in garden cucumber samples 22.85 and 62.28%, respectively. The results of combined health risks assessment indicated that HQ values mean due to the consumption of unwashed garden cucumbers, for adults and children were 0.18 and 0.73, respectively. Also, HQ values mean due to the consumption of unwashed greenhouse cucumbers, for adults and children were 0.33 and 1.34, respectively. Conclusion: In general, the mean residues of pesticide in samples of unwashed, washed and peeled greenhouse cucumber were above MRL in 100%, 100% and 87.5%, respectively. Also, the mean residues of pesticide in samples of unwashed, washed and peeled garden cucumber were above MRL in 100%, 87.5% and 50%, respectively. Keywords: Pesticide, Cucumber, Health Risk Assessment, Tabriz, Children