Dissipation of Chlorpyrifos in the bottled tea beverages and the effects of EGCG

Bottled tea beverages (BTB) are popular for the benefits to human health and convenience. Because Chlorpyrifos (CP) is commonly used as a biomarker for exposure as well as a pesticide in the field, it is important to determine the dynamics of CP dissipation in BTB in order to better perform risk assessments. This study focused on the dynamic behavior of CP for 22 days by fortifying bottled green tea (GT), dark tea (DT), and Oolong tea (OT) beverages with the parent chemical and analyzing the degradation products. Photo-induction was used to generate the two transient intermediates, i.e. the reactive oxygen species (ROS) from H₂O₂ and the triplet state of CP ( 3 CP*) from the parental, in water was designed to observe the effects of (−)-Epigallocatechin-3-gallate (EGCG) on the dissipation and transformation of CP. The results indicated that the CP degraded in BTB and the main products were detected. The half-life values of CP illustrated that EGCG increased the dissipation of CP by combination with CP, and inhibited the generation of CP -oxon by scavenging the emerged oxidant ROS and interfering the transformation of 3 CP*. This work suggests EGCG could play the various roles on the dissipation and transformation of CP. Thus, a comprehensive identification of CP degradation should be performed when assessing the exposure risk in the drinking of bottled tea beverages.