Determination of propineb residue in consumed tea

The use of pesticides is essential to pests control in horticultural crops for the production of an adequate food supply for an increasing world population and for the control of insect-borne diseases. Therefore, pesticide residues in environment and food have a negative impact on the health of living organisms especially human. In this regard, the present study was carried out for assessment and comparing of propineb residues in Iranian tea and imported consumed tea.
In this experimental study, according to the Cochran's sample size formula, 12 samples from 4 brand of imported tea and 6 samples from 2 brand of Iranian tea were collected from market basket of Hamadan City in 2015. After preparation and processing the samples in the laboratory, propineb residues in samples determined using a spectrophotometric method to a wavelength range of 400 nm in 5 replications. Recovery tests were carried out using pesticide-free samples. Also, all statistical analyses were performed using the SPSS statistical package version 19 (Chicago, IL, USA).
The mean concentration of propineb residues in Iranian tea samples were 1.60±0.27 µg/kg and in imported tea samples were 0.78±0.63 µg/kg, respectively and lower than the maximum residue limit (MRL) provided by the European Commission (100 ppb). The results of the comparison of the mean concentration of pesticide residues between Iranian and imported tea samples revealed no statistically significant differences between all the samples together (P=0.17).
The results showed that the residues of propineb were found in all analyzed tea specimens. But according to the mean concentrations of propineb residues in tea samples marketed in Hamedan City were lower than MRL, therefore, no adverse health effects have been established from controlled consuming of tea. Also, concerning increased use of agricultural inputs especially kind of pesticides for pest management by farmers, regular periodic monitoring of chemical pollutants content in Iranian and imported tea are recommended for food safety.