Honeybees and bee products are potential bioindicators of the presence of contaminants in the environment,
enabling monitoring of large areas due to the long distances travelled by bees. This work
evaluates the use of bee pollen as a bioindicator of environmental contamination by pesticides. A GC-MS/
MS analytical method for multiresidue determination of 26 different pesticides in pollen was developed
and validated in accordance with the recommendations of the European Union SANCO guide. Environmental
monitoring was conducted using the analysis of 145 pollen samples collected from ten beehives
in the experimental apiary of Embrapa in Jaguariúna (S~ao Paulo State, Brazil). Bioallethrin and pendimethalin
were identified in four and eighteen samples, respectively, at concentrations below the LOQ of
the method (25 ng g1). Passive sampling with polyurethane foam discs was used as a control, and no
pesticides were found. The detection of pesticide residues in seven samples (33%) from commercial
apiaries in Ribeir~ao Preto (S~ao Paulo State) confirmed the efficiency of the analytical method and the
need for environmental monitoring for the presence of pesticide residues. The results demonstrated the
potential of bee pollen as a bioindicator of environmental contamination by pesticides