Evaluation of nitrate and nitrite accumulation in vegetables exposed on ShahreKord's markets

Document Type : Research Paper

Authors

1 Assistant Professor, Department of Soil Science, College of Agriculture, ShahreKord University, ShahreKord, Iran

2 - Former MSc. Student of Soil Science, College of Agriculture, ShahreKord University, ShahreKord, Iran

Abstract

In the last years, the presence of nitrates and nitrites in vegetables has been a public health concern. This study was conducted to examine the accumulation of nitrate and nitrite in vegetables of Shahre-Kord retails. For this purpose, a total of 222 fresh vegetables samples were collected in winter 2011 and summer 2012 and were analyzed for the accumulation of nitrate and nitrite. Results showed a vast deviation between the mean concentrations of nitrate. In other words, the nitrate accumulation for mint was 310.9 mg/kg fresh weight (FW) and for savory was estimated at 3309.1 mg/kg FW. Nitrate accumulation in more than 85% of the vegetable samples was below the approved limit of 2500 mg/kg FW; meanwhile in savory it was higher than 3000 mg/kg FW. Moreover it was revealed that in comparison with nitrate, the mean value of nitrite accumulation was remarkably low (below 1.65 mg/kg FW). According to the results, the nitrate accumulation was significantly (P<0.05) higher in the samples obtained during the summer, but in the case of nitrite the results were reversed. In conclusion the levels of nitrate and nitrite in vegetables of ShahreKord retails were unlikely to pose any health hazard to the general population; nonetheless, the application of efficient techniques for decreasing the nitrate and nitrite accumulation in vegetables is recommended.

Keywords


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