Antibiotic exposure across three generations from Chinese families and cumulative health risk

Extensive antibiotic exposure in the general population has been documented by bio-monitoring, but data regarding antibiotic burden across three generations in families living in the same household are lacking. We investigated the distribution of antibiotics and the potential health risk among the three generations by selecting 691 participants from 256 households in Fuyang city, China. A total of 45 antibiotics and two metabolites were screened in urine samples through liquid chromatography electrospray tandem mass spectrometry. In total, 34 antibiotics were found in the samples with an overall detection frequency of 92.0%, and the detection frequencies of individual antibiotic ranged from 0.3% to 28.7%. Specifically, the concentrations of seven antibiotics (azithromycin, amoxicillin, oxytetracycline, levofloxacin, norfloxacin, trimethoprim and sulfamethoxazole) were extremely high (i.e., above 10, 000 ng/mL). The detection rates of tetracyclines were significantly different among the three generations, with parents having the highest detection rate. Penicillin V, chlortetracycline, doxycycline, enrofloxacin, and ciprofloxacin showed a higher detection frequency in parents, whereas tetracycline, danofloxacin, and ofloxacin were more likely to be found in grandparents. The proportions of the sum of the daily exposure dose of VAs and PVAs more than 1 μg/kg/d in children, parents, and grandparents were 31.6%, 39.5%, and 26.5%, respectively. A hazard index (HI) greater than 1 was observed in 14.7% children, which was less than the 23.6% in parents and slightly higher than the 11.8% in grandparents. Ciprofloxacin was the biggest contributor to HI among the three generations. Collectively, these findings indicate that households are widely exposed to various antibiotics in Fuyang city, where parents had the highest health risk associated with the disturbance of gut microbiota.