Distribution and risk assessment of antibiotic and bisphenol compounds residues in drinking water sources of Guangdong.

The safety of the source of drinking water is important to human health, and monitoring the occurrence of contamination, particularly antibiotics and toxic organic compounds, is critically essential. Such information also helps in managing and improving water quality. However, the degree and details of this contamination in drinking water sources of Guangdong province are still not clear. This study determined the residues of antibiotics and bisphenol compounds (BPs) in three water sources, including two reservoirs and one river, in Guangdong province, aiming to evaluate the drinking water safety and health risk. The results showed that a total of 32 antibiotics and 3 BPs (BPAF, BPs, BPA) were detected in March. The total concentration antibiotics and BPs ranged from not detected (nd) to 243.65 ng/L and nd to 7.47 ng/L, respectively. In August, a total of 35 antibiotics and 3 BPs (BPAF, BPS, BPA) were detected. The total concentrations of antibiotics and BPs ranged from 0.11 to 1793.72 ng/L and nd to 59.15 ng/L, respectively. The concentration of pollutants in August (wet season) was significantly higher than that in March (dry season). Principal component analysis showed that non-point source pollution concentrations increased in river-type water sources. The concentration of pollutants was generally higher in river water than in reservoir water. In addition, seasonal variations were observed. Health risk assessments for antibiotics indicate that chlortetracycline and oxytetracycline pose risks to the 0–3 month and 3–4 year age groups. The results of the ecological risk assessment revealed that in March and August, sulfamethoxazole, tetracycline, clarithromycin, lincomycin, roxithromycin, oxytetracycline, and enoxacin posed moderate or high risks. BPS posed a moderate risk at all sampling sites, while BPA presented a high risk. This study reveals the contamination problems of drinking water sources and provides the basis for the pollution control of water in Guangdong Province. [ABSTRACT FROM AUTHOR]