Determination of Arsenic Species in Ophiocordyceps sinensis from Major Habitats in China by HPLC-ICP-MS and the Edible Hazard Assessment

Abstract

This study sought to determine the concentration and distribution of arsenic (As) species in Ophiocordyceps sinensis (O. sinensis), and to assess its edible hazard for long term consumption. The total arsenic concentrations, measured through inductively coupled plasma mass spectrometry (ICP-MS), ranged from 4.00 mg/kg to 5.25 mg/kg. As determined by HPLC-ICP-MS, the most concerning arsenic species—AsB, MMAV, DMAV, AsV, and AsШ—were either not detected (MMAV and DMAV) or were detected as minor As species (AsB: 1.4–2.9%; AsV: 1.3–3.2%, and AsШ: 4.1–6.0%). The major components were a cluster of unknown organic As (uAs) compounds with AsШ, which accounted for 91.7–94.0% of the As content. Based on the H2O2 test and the chromatography behavior, it can be inferred that, the uAs might not be toxic organic As. Estimated daily intake (EDI), hazard quotient (HQ), and cancer risk (CR) caused by the total As content; the sum of inorganic As (iAs) and uAs, namely i+uAs; and iAs exposure from long term O. sinensis consumption were calculated and evaluated through equations from the US Environmental Protection Agency and the uncertainties were analyzed by Monte-Carlo Simulation (MCS). EDItotal As and EDIi+uAs are approximately ten times more than EDIiAs; HQtotal As and HQi+uAs > 1 while HQiAs < 1; and CRtotal As and CRi+uAs > 1 × 10−4 while CRiAs < 1 × 10−4. Thus, if the uAs is non-toxic, there is no particular risk to local consumers and the carcinogenic risk is acceptable for consumption of O. sinensis because the concentration of toxic iAs is very low.

Keywords

• Ophiocordyceps sinensis
• arsenic speciation
• risk assessment
• HPLC-ICP-MS