Pesticide residues in beeswax from Western Spain: Toxicological risk for bee health and beekeeping productivity

The pesticide residues in beeswax pose a risk to bee health and hive productivity. This study analyzed 25 beeswax samples from apiaries across five regions in Extremadura, a key beekeeping area in Spain. Foundation wax samples were also sourced from three common suppliers to evaluate contamination at the origin. A multi-residue of 560 substances was performed using QuEChERS extraction, LC-MS, and GC-MS methods. The results revealed 18 insecticides, 7 fungicides, and 4 herbicides, including banned substances such as endrin (up to 218.57 µg/kg) and chlorfenvinphos (15–16 µg/kg). Acrinathrin (5.27–122 µg/kg) and tau-fluvalinate (6.5–138.79 µg/kg) were the most frequent residues. Foundation wax accumulated 16 pesticide residues, highlighting its potential as a source of contamination. Banned pesticides have also been detected. These findings highlight the importance of monitoring pesticide residues in commercial foundation waxes and assessing the impact of pesticide exposure from wax on beekeeping and human safety.