Common and novel methods for the identification of bisphenol A in tea samples: A systematic review study

[Display omitted] •Bisphenol A is a estrogenic compound that may be in tea.•Common methods of tea sample preparation for tea measurement are SPE column and QuEChERS.•Novel methods of tea sample preparation are the use of supramolecular solvent and nanoparticles. Tea is the most widely consumed beverage in the world, so its safety is of particular importance. Bisphenol A (BPA) is a pollutant that has been identified in the environment. This systematic study was conducted with the focus on the amount of BPA in tea. Searching in databases was done with related keywords without limitation in time. In most studies, bisphenol A has been detected in tea samples. The range of bisphenol A in tea samples is between ND (not detected) and 219 ng/g. In about 28 % of the studies, the level of bisphenol ND has been reported. Conventional and new techniques for measuring bisphenol in tea are also discussed in this manuscript. The common methods are the use of SPE (Solid-Phase Extraction) and QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) method. However, novel methods, including the use of covalent organic frameworks and Nano particles, are outstanding researches.