摘要

环境中可能影响细菌抗生素耐药性的污染物的迁移是生态和人类健康风险管理中的一个重要问题。农业区是与粮食作物和畜牧生产相关的实践可能引入污染物的地方，这些污染物可能会改变微生物群中抗生素抗性发展的选择压力。在使用动物粪肥或市政生物固体作为废物和/或肥料可能影响病原菌种类抗生素耐药性选择的地区，这一点很重要。为了研究可能导致细菌产生抗生素抗性的污染物的环境迁移，研究了加拿大农业活动强度最高的流域之一;位于不列颠哥伦比亚省温哥华以东60公里的Sumas河。这项为期两年的评估监测了四种选定的四环素抗性基因（tet（O），tet（M），tet（Q），tet（W））和水质参数（温度，电导率，浊度，悬浮固体，硝酸盐，磷酸盐和氯化物）在整个流域的八个地点。 Sumas河网络中的四环素抗性基因（Tcr）丰度在1.47×102和3.49×104copies / mL范围内，在对照流（远离农业活动）的范围内，介于2.3和6.9copies / mL之间，持续时间研究。此外，与旱季月份（介于0.6和31.2copies / mL之间）相比，在潮湿季节月份检测到的Tcr丰度介于1.3×103和2.29×104copies / mL之间。 2005年11月在高降雨期间观测到的最高运输率在1.67×1011和1.16×1012copies / s之间。该研究表明，浓度为102-104copies / mL的抗生素抗性基因的浓度升高可以通过农业流域中的流网络，但季节变化强烈影响这些基因的特定运输模式。

Environmental transport of contaminants that can influence the development of antibiotic resistance in bacteria is an important concern in the management of ecological and human health risks. Agricultural regions are locales where practices linked to food crop and livestock production can introduce contaminants that could alter the selective pressures for the development of antibiotic resistance in microbiota. This is important in regions where the use of animal manure or municipal biosolids as waste and/or fertilizer could influence selection for antibiotic resistance in pathogenic bacterial species. To investigate the environmental transport of contaminants that could lead to the development of antibiotic resistance in bacteria, a watershed with one of the highest levels of intensity of agricultural activity in Canada was studied; the Sumas River located 60 km east of Vancouver, British Columbia. This two-year assessment monitored four selected tetracycline resistance genes (tet(O), tet(M), tet(Q), tet(W)) and water quality parameters (temperature, specific conductivity, turbidity, suspended solids, nitrate, phosphate and chloride) at eight locations across the watershed. The tetracycline resistance genes (Tcr) abundances in the Sumas River network ranged between 1.47 × 102 and 3.49 × 104 copies/mL and ranged between 2.3 and 6.9 copies/mL in a control stream (located far from agricultural activities) for the duration of the study. Further, Tcr abundances that were detected in the wet season months ranged between 1.3 × 103 and 2.29 × 104 copies/mL compared with dry season months (ranging between 0.6 and 31.2 copies/mL). Highest transport rates between 1.67 × 1011 and 1.16 × 1012 copies/s were observed in November 2005 during periods of high rainfall. The study showed that elevated concentrations of antibiotic resistance genes in the order of 102–104 copies/mL can move through stream networks in an agricultural watershed but seasonal variations strongly influenced specific transport patterns of these genes.

https://www.sciencedirect.com/science/article/pii/S0048969718303206