Method development, multi-residue determination, and dietary exposure risk assessment of plant growth regulators in homologous materials of medicine and food

Residues of plant growth regulators (PGRs) in homologous materials of medicine and food threaten public health. This study aimed to develop a rapid, sensitive, and high-throughput method for simultaneously determining 16 PGR residues in homologous materials of medicine and food. Furthermore, the established method was applied to actual samples to assess the potential exposure risk of multi-PGR residues. A modified high-throughput quick, easy, cheap, effective, rugged, and safe (QuEChERS) method coupled with ultra-high-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) was developed and validated. The extraction solvent, type of extraction method, and subsequent purification techniques were investigated to achieve a better analysis of the target. Risk assessment was based on chronic dietary risk assessment. Ultrasonic extraction with 1% formic acid-acetonitrile was employed, and MgSO4 + NaAc was selected as the clean-up sorbent. The 16 PGRs showed a good linear relationship in the range of 1 similar to 200 mu g/L (r >= 0.9960), with detection limits ranging from 0.3 to approximately 3 mu g/kg. The recovery rate ranged from 65 to 109%, with RSD from 0.01 to 10% (n = 6). The total detection rate of 16 PGRs in the samples was 87%. The risk assessment indicated that the multi-residues of PGRs in homologous materials of medicine and food would not pose a potential risk to human health. This work provides a valuable reference for the monitoring of multiple PGRs. It has also improved our understanding of the possible exposure risk of PGR residues in homologous materials of medicine and food.