In vitro assessment of the pesticide bioaccessibility in Dendrobium officinale Kimura et Migo.

Bioaccessibility (BA) is a crucial factor for evaluating the absorption of pollutants in the human digestion system, which is of vital importance for risk assessment of pollutants via food intake. Multi-pesticides were detected in Dendrobium officinale Kimura et Migo (D. officinale), a popular dual-use plant with both botanical medicine and food applications. Nevertheless, the BA of pesticides in D. officinale remains unknown, restricting its market size. Herein, the BA of 19 pesticides with varying properties was evaluated by using an in vitro digestion model, showing BA values between 27.4 and 96.8%. The BA was controlled by the hydrophobicity and water solubility of pesticides, since the significant correlation between these two factors and BA values was observed. Moreover, co-ingested food ingredients could influence the BA, wherein the effect was significant for pesticides of logK values no less than 3. Lipids enhanced the BA by 9-66%, whereas proteins or carbohydrates decreased BA values by 6-28%. In particular, considering the BA, the risk quotient values were reduced by 3-73%. Clearly, this work suggested that traditional risk assessment without considering the BA would seriously overestimate the actual risk of pesticides in food.