Monitoring of ivermectin residues in bovine and pork tissues

Abstract

Argentina is traditionally a beef-producing country. However, in recent years other productions have grown exponentially. Due to improvements in technology, changes in customs, or economic issues, consumer preferences have changed for cheaper meats. Animal production systems, both extensive and intensive, are closely linked to veterinary drug use for prevention, control, or treatment of parasitic diseases. Consequently, if good agricultural practices are not respected, products obtained from these productions could present residues above the Maximum Residue Limits (MRLs). In this context, ivermectin (IVM), an endectocide drug belonging to the macrocyclic lactone group, is one of the most widely used to treat parasitic diseases. IVM residues above the MRLs in bovine and pork tissues may constitute a risk to consumer health. Consequently, the current study aimed to assess the presence of ivermectin residues in bovine and pork tissues for local consumption in Buenos Aires province (Argentina). Samples of bovine/pork meat and fat, and bovine liver and kidney were taken for 3 years during the winter and summer seasons in 5 cities of Buenos Aires province. Tissue samples were analyzed by HPLC with a fluorescence detector. Of a total of 691 samples analyzed, 87 of them presented residues of IVM. However, only 13 samples from the positive ones showed concentrations above the Codex MRL. Mean IVM concentrations (range) were 42.18 (0.11?587.15), 31.66 (2.96?283.33), 162.61 (1.32?516.55), 22.78 (1.51?65.40), 15.26 (0.07?194.25) and 22.14 (1.58?126.76) ppb for bovine meat, bovine fat, bovine liver, bovine kidney, pork meat, and pork fat, respectively. In conclusion, bovine and pork tissue ingestion is safe for the consumer. However, 1.88% of the samples showed IVM concentrations above de MRL, thus the implementation of residue surveillance programs at the local level guaranteeing consumer health is strongly recommended.