Investigation of residual pesticides, veterinary drugs, and mycotoxins in feed using multi-class hazardous materials analytical method

In Korea, a large proportion of raw materials and compound feeds are imported. To manage domestically regulated residual and contaminant substances, a modified QuEChERS and QuPPe analytical method was developed to analyze various classes of hazardous substances. Through validation, it was confirmed that quantitative analysis was possible for 327 pesticide residues, 7 mycotoxins, and 121 veterinary drug residues. The method was applied to three matrices—corn feed, livestock compound feed, and pet food—at concentration levels of limit of quantitation (LOQ), 2LOQ, and 5LOQ, with three replicates each. The recovery results ranged from 60.8% to 119.7%, and relative standard deviation (RSD) was less than 15.0%. Using the established method, monitoring was conducted on a total of 546 feed samples distributed in Korea (239 single-ingredient feeds and 307 compound feeds). Among pesticide residues, pirimiphos-methyl, piperonyl butoxide, and propiconazole were the most frequently detected. In single-ingredient feeds, higher detection rates were observed in fiber, bran, and meal types. In compound feeds, the detected substances differed between livestock and pet food, which was attributed to differences in raw materials. Most veterinary drugs were not detected, although some compounds such as clopidol were found at levels below the quantification limit. All detected mycotoxins were within the acceptable or recommended limits. However, some substances not regulated domestically or not registered for use in Korea were detected. The characteristics of these substances—including toxicity, exposure routes, regulatory standards, and feed-specific residue tendencies—were investigated.