Sichuan pepper, a pungent culinary spice, as well as
a traditional
medicinal plant, is widely used in Asian countries. Currently, pesticide
combinations are still the most important tools for controlling insect
pests to ensure the production of Sichuan pepper. However, there are
limited data regarding the potential hazards posed by residues of
these substances in Sichuan pepper products. In this study, a QuEChERS
technique via UPLC-MS/MS for multianalysis of flonicamid and acetamiprid
in fresh and dried Sichuan pepper was established with mean recoveries
of 96–104%, relative standard deviations of ≤11%, and
limits of quantifications of 0.01 mg/kg. A multisite field trial research
was conducted to evaluate the persistence, processing factor, and
dietary risk of flonicamid and acetamiprid in Sichuan pepper collected
from four representative cultivation areas in China by the validated
technique. The dynamic experiment indicated that flonicamid and acetamiprid
degraded easily in Sichuan pepper with half-lives of 3.7–6.5
and 6.2–28.9 days, respectively. The residue concentrations
of flonicamid and acetamiprid increased after the processing step
with a processing factor higher than 1. The long-term dietary risk
caused by residues of flonicamid and acetamiprid in Sichuan pepper
is negligible, indicating that the application of these pesticides
in Sichuan pepper cultivation was unlikely to pose adverse effects.
Ultimately, in order to ensure food security, the maximum residue
limits (MRLs) of flonicamid and acetamiprid were recommended at 1
and 2 mg/kg for dried Sichuan pepper, respectively, based on residue
chemistry data and dietary assessment results. This study offers insights
into the appropriate scientific application of the new commercial
formulation in Sichuan pepper and contributes valuable data for the
establishment of MRLs for flonicamid and acetamiprid in the future.