OBJECTIVE  To establish a UHPLC-MS/MS method for determining 8 plant growth regulators(PGRs) in Atractylodis Macrocephalae Rhizoma, to establish corresponding maximum residue limits, and to conduct a preliminary risk assessment.

METHODS  Chromatographic separation utilized acetonitrile-0.01% formic acid mobile phase under gradient elution, with MRM detection via polarity switching, followed by method validation. PGRs residue risks were assessed through chronic hazard quotient and acute hazard quotient, referencing domestic and international standards for food and medicinal herbs.

RESULTS  All 8 PGRs exhibited satisfactory linearity within their respective detection ranges, with correlation coefficients ≥0.994 8. Mean recoveries across 3 fortification levels ranged from 91.2% to 140.4%. Analysis of 30 Atractylodis Macrocephalae Rhizoma batches detected 7 PGRs, showing an overall detection frequency of 76.67%. Risk assessment determined both chronic hazard quotient and acute hazard quotient values <1, indicating low dietary exposure risks associated with PGR residues in this medicinal material.

CONCLUSION This method demonstrates high sensitivity, good accuracy, and simple and rapid sample preparation, making it suitable for determining PGRs residue in Atractylodis Macrocephalae Rhizoma. Although PGRs residue in Atractylodis Macrocephalae Rhizoma pose acceptable risk levels, long-term use in traditional Chinese medicine may still pose health risks due to accumulated low-dose exposure. Enhanced regulatory oversight is recommended. Establishing residue limit standards would standardize cultivation and production practices, ensuring the safety and efficacy of this medicinal material.