The difference of trophic magnification factors of Quinolones antibiotics (QNs) between pelagic and benthic foodwebs in a shallow lake: importance of carbon and nitrogen sources

Feeding habitat and carbon source play critical roles in certain the trophic transfer and bioaccumulation ability of chemicals in aquatic ecosystems. However, it remains largely unknown how these factors affect the trophic magnification factors (TMFs) of antibiotics in lake ecosystem. This study compared the differences of TMFs for Quinolones (QNs) antibiotics and carbon/nitrogen sources between pelagic foodweb (PFW, 11 species) and benthic foodweb (BFW, 14 species) in Baiyangdian Lake, Northern China. delta C-13 showed higher values in BFW, while delta N-15 appeared higher values in PFW. The mean percentage of pelagic nitrogen source (PNS) was higher than benthic nitrogen source (BNS), while the mean percentages of pelagic carbon source (PCS) and benthic carbon source (BCS) were approximately equal. Relatively high concentrations of enmfloxacin (ENR), flumequine (FLU), norfloxacin (NOR), and ofloxacin (OFL) were detected, and the total concentrations of QNs were 27.73-126.4 ng/g dw in PFW, while 23.49-121.3 ng/g dw in BFW. ENR and NOR appeared trophic magnification, while FLU and OFL exhibited tmphic dilution. The TMFs of these QNs in PFW were significantly higher than in BFW. The concentration of QNs in biological samples were significantly positive correlation with delta N-15, while negative correlated with delta C-13. The TMFs for FLU and OFL were positively correlated with PCS/PNS, while negatively correlated with BCS/BNS. The opposite was true for NOR and ENR. Capsule abstract: First studied the differences of TMFs for typical QNs and carbon/nitrogen sources between PFW and BFW in a shallow lake.

Automated summary

This study compared the differences in TMFs for QN antibiotics and carbon/nitrogen sources between the pelagic foodweb and benthic foodweb in Baiyangdian Lake, Northern China. It was found that the TMFs of QNs were significantly higher in the pelagic foodweb, and were closely related to the ratios of carbon/nitrogen sources.