Analysis of Carbamate Pesticides Residues and Risk Assessment in Tea (Camellia sinensis)

The tea plant (Camellia sinensis (L.) O. Kuntze) is a major crop in Taiwan, and tea is the most widely consumed beverage worldwide. However, due to increasing public concern for presence of pesticide residues in tea, many consumers have been skeptical that the tea available on market shelves is necessarily safe. The aim of this study firstly was to develop optimization multiresidue analysis methods (MRMs) to determine the nineteen carbamate pesticides in tea samples. Secondly it was to evaluate the dissipation of carbofuran and carbaryl according to field growth periods, manufacturing processing and roasting. Thirdly it was to investigate the carbamate pesticide residues in tea and evaluate the risk of carbamate pesticides in tea.
The results indicate that the proposed method provides a trace level screening determination of carbamate pesticides residues in tea samples. The presence of carbofuran and carbaryl in tea can be reduced by proper field management, manufacturing and roasting processes. The detected levels of carbamate pesticides residues were further compared with the maximum residue levels (MRLs). And the detected levels of carbamate pesticides residues found were generally very low, representing a low consumer exposure to pesticides through the consumption of tea.
This knowledge is vital to help tea farmers to establish consistent safety controls for tea culture management, achieve safe tea products and ensure worry-free tea consumption. The study is also important for the benchmark establishment among international standards.