Occurrence and risk assessment of coccidiostat residues in chicken meat: A regional study in southeast China

This study investigated the occurrence of coccidiostat residues in chicken meat and conducts a probabilistic health risk assessment. A total of 277 samples were collected from various regions in southeast China, and 3 coccidiostat residues and 1 metabolite were analyzed by UHPLC-MS/MS. The spiking recoveries of instrumental analysis were ranged from 90.2% to 98.3%. The distribution showed detection frequencies for diclazuril (11.19%) and nicarbazin (9.45%), with average concentrations of 1.78 μg/kg and 1.12 μg/kg, respectively. Maximum values were 71.8 μg/kg for diclazuril, 221 μg/kg for nicarbazin, 144 μg/kg for toltrazuril, and 84.3 μg/kg for toltrazuril sulfone. No significant differences in residue concentrations were observed across different sampling years and months; however, certain months showed higher average levels, potentially linked to environmental factors influencing Eimeria parasite life cycles. The study also revealed higher concentrations of nicarbazin in samples from farmer's markets than stores. Risk assessment based on dietary exposure indicated that estimated daily intakes of coccidiostats were significantly lower than the acceptable daily intake, which indicated no public health risk. However, the potential long-term ecological and agricultural impacts of coccidiostat residues necessitate ongoing surveillance and responsible use in poultry farming.