Multi-residue monitoring and dietary risk assessment of 17 pesticides and 3 related metabolites in rice and rice flour from markets in China.

Abstract

Pesticide residues in rice have attracted widespread public attention in recent years. This research aimed to monitor the residues of 17 pesticides and their 3 metabolites in 120 samples of rice and rice flour collected from markets in China using the QuEChERS (Quick, Easy, Cheap, Effective, Rugged, Safe) pretreatment method combined with high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). The monitoring results showed that isoprothiolane, tricyclazole, fenoxanil, and tebuconazole were detected in the rice samples, with detection frequencies of 33.3%, 17.5%, 8.3%, and 2.5%, and concentrations ranging from 0.02 to 0.1 mg/kg (median = 0.04), 0.01 to 0.17 mg/kg (median = 0.14), 0.04 to 0.06 mg/kg (median = 0.05), and 0.01 to 0.02 mg/kg (median = 0.01), respectively. The residues of these four pesticides were all below their corresponding maximum residue levels (MRLs) set by China. Additionally, isoprothiolane, tricyclazole, fenoxanil, and tebuconazole were detected in rice flour samples, with detection frequencies of 74.2%, 55.0%, 5.0%, and 2.5%, and concentrations ranging from 0.01 to 0.1 mg/kg (median = 0.04), 0.01 to 0.04 mg/kg (median = 0.02), 0.01 to 0.06 mg/kg (median = 0.03), and 0.02 to 0.04 mg/kg (median = 0.03), respectively. Furthermore, the chronic dietary intake risk (HQc), the acute dietary intake risk (HQa), and cumulative dietary risk (HI) for all the detected pesticides were evaluated and found well below 100%, indicating that the dietary intake risks would not pose potential health risks.