南方某水库水体中抗生素生态与健康风险研究

Assessments of Ecological and Health Risk Induced by Antibiotics in Source Water of a Reservoir in a Southern City

环境中大量残留的抗生素将对生态环境和人体健康造成潜在危害。本研究采用风险商值法(RQ)评价了林肯霉素、红霉素(脱水)、罗红霉素、磺胺甲噁唑、磺胺二甲嘧啶、头孢呋辛、头孢氨苄、甲硝唑、阿莫西林和氯霉素10种抗生素对南方某水库水体产生的生态风险,并对10种抗生素进行了化学非致癌物风险评价。结果表明,7个采样点中共检出8种抗生素,残留量在1.2~130.0 ng·L^(-1)之间。红霉素(脱水)、林肯霉素、磺胺甲噁唑这3种抗生素在丰水期、枯水期的所有采样点均有检出,磺胺二甲嘧啶和头孢呋辛在枯水期的检出率也为100%,而氯霉素和阿莫西林在7个样点均未检出。风险评价结果表明,除个别样点外,该水库抗生素残留的整体风险不高。丰水期和枯水期A河水体中磺胺甲噁唑的生态风险商大于1,A河(丰水期和枯水期)、B河(丰水期)和库中3号样点(枯水期)的联合毒性风险商大于1,表明这3个样点的抗生素残留对生态环境存在较严重的威胁,其余采样点抗生素的联合毒性风险商处于0.1到1之间,需长期观测其抗生素的环境动态,以避免高风险危害的发生。该水库10种抗生素残留引起的非致癌物风险数量级在10^(-1)5到10^(-1)2之间,说明该水库中10种抗生素通过饮水途径引起的非致癌风险很低,远低于可接受风险水平,甚至远低于可忽略风险水平。

A large amount of environmental residues of antibiotics cause hazards and risks to the ecological envi- ronment and human health. In this paper, the ecological and health risk assessments were performed to evaluate the risk of 10 kinds of antibiotics, including lincomycin, erythromycin-H20, roxithromycin, sulfamethoxazole, sulfadi- midine, cefuroxime, cefalexin, metronidazole, amoxicillin and chloromycetin, in a reservoir in a southern city, Chi- na. Results showed that 8 kinds of antibiotic were detected in 7 sampling points, with the concentrations ranged from 1.2 to 130 ng. L-1. The detection frequency of erythromycin-H20, lincomycin, sulfamethoxazole reached 100% both in high flow period and low flow period, while sulfadimidine and cefuroxime could only be detected in low flow period. However, chloromycetin and amoxicillin could not be detected in the selected 7 sampling points. Further risk assessment results showed that the overall risk was not high except some points. The risk quotients ex- ceeded 1 for the sulfamethoxazole in River A （both high flow and low flow periods）. Among sampling points, the combined risk quotients of all 10 antibiotics in River A （both high flow and low flow periods）, River B （high flow period） and point 3 in the reservoir （low flow period） were higher than 1. It indicated that the residuals of antibiot- ics had high ecological risk in these stations. The risk quotients of other stations ranged from 0.10 to 1.00, illustra- ting that the long-term observations for antibiotics residuals in water are necessary. The sum of non-carcinogenic risks for the 10 antibiotics was in range of 10-^15 to 10-^12, suggesting the acceptable health risks associated with anti- biotics in the source water of the reservoir.