Investigation and Risk Characterization on the Contamination Level of Herbal Medicines Without Legal Benzo(a)pyrene Specification

− By analysing the benzo(a)pyrene concentration using HPLC-FLD and LC-MS/MS, pollution levels of herbal medicines without permitted benzo(a)pyrene specification were investigated. Average benzo(a)pyrene concentrations were 38.30, 37.46 and 21.22 µg/kg for Amomi Tsao-ko Fructus, Mume Fructus and Coptidis Rhizoma, respectively, which are 4 to 7 times higher than maximum permitted benzo(a)pyrene concentration of Rehmanniae Radix Preparata and Rehmanniae Radix, i.e. 5.0 µg/kg. Proportion of detected samples exceeding 5.0 µg/kg benzo(a)pyrene concentration was 22% for Cimicif-ugae Rhizoma and Scrophulariae Radix, 44% for Forsythiae Fructus, 67% for Mume Fructus, 100% for Amomi Tsao-ko Fruc-tus and Coptidis Rhizoma, and collectively 29% (36 out of 125 samples) in average. In terms of risk characterization results, human exposure of benzo(a)pyrene were 7.96, 3.49 and 1.61 ng/kg b.w./day and the margin of exposure(MOE) were 1.25 × 10⁴, 2.86 × 10⁴ and 6.20 × 10⁴ for Mume Fructus, Amomi Tsao-ko Fructus and Coptidis Rhizoma, respectively. MOE banding of those herbal medicines was categorized to ‘low concern’. However, considering that human exposure of benzo(a)pyrene for food is legislated to 1.4~2.5 ng/kg b.w./day, it was urgent to set up the guideline of benzo(a)pyrene in herbal medicines.