Synergistic hepatic metabolic effects induced by coexposure to the fungicides carbendazim and procymidone in rats

Carbendazim (CBZ) and procymidone (PRO) are two fungicides widely used for decades. With excessive use, potential public health risks from their coresidues in vegetables and the environment have attracted increasing attention. Here, 6-week-old male SD rats are orally gavaged with 200 mg/kg CBZ, 200 mg/kg PRO, or 200 mg/kg CBZ + 200 mg/kg PRO (Mix group). At 1, 8 and 72 h postexposure, liver samples were collected and subjected to untargeted metabolomic analysis. Sparse partial least squares discriminant analysis (sPLS-DA) shows that all treatment groups exhibit significant separation from the Control group. Meanwhile, the Mix group is also significantly separated from the individual treatment groups. At 1 and 8 h postexposure, differentially abundant metabolites are predominantly enriched in fatty acyls according to HMDB classification, and the levels of 12-keto-eicosatetraenoic acid (12-KETE) are significantly elevated across treatment groups. 12-KETE acts as a PPARγ ligand and regulates PPARγ signaling pathways. The Mix-8 h group exhibits the largest number of differentially abundant metabolites. KEGG enrichment analysis identifies two uniquely enriched pathways with high impact (phenylalanine, tyrosine and tryptophan biosynthesis and linoleic acid metabolism). Within these pathways, linoleic acid, 13(S)-HPODE and L-tyrosine are significantly decreased only in the Mix-8 h group. Time-course analysis reveals diverse patterns of altered differentially abundant metabolites rather than a simple monotonic trend. Additionally, hepatic metabolite profiles remain separated among treatment groups after 72 h postexposure, although CBZ and PRO residues are hardly detected. Collectively, these results indicate that coexposure to CBZ and PRO amplifies hepatic metabolic disruption and produces mixture-specific toxic effects.