Archives
To our knowledge this study collected all published research
To our knowledge, this study collected all published research of occurrence of BMS 309403 synthesis in water, sediment and aquatic organisms of typical Lakes by 2017 according to http://www.cnki.net/, https://xue.glgoo.net/, http://xueshu.baidu.com/, and http://www.sciencedirect.com/. Some information of Lakes are provided in Table S1. This review aims to summarize the contamination status of current antibiotics and antibiotic resistance genes in different environmental media of Lakes in China and assess their potential threats to environment and health risk. The results could provide reliable information regarding the exposure and risk levels of antibiotics of Lakes in China, which are important for establishment the supervision legal framework (market entry permitting system, drug advertising restrictions and strict and clear application process for antibiotic use) of the antibiotic misuse and the water quality criteria and discharging standard of antibiotics.
Occurrence
Risk
Conclusions and suggestions
Antibiotics are ubiquitous in different environmental media in the aquatic environments of lakes in China. The levels of antibiotic contamination in surface water range from ngL−1 to μgL−1, while its levels in sediment and aquatic organisms range from ngg−1 to μgg−1 (dw). The exposure level of antibiotics in water and sediment is relatively high on the global scale. In addition, the differences in levels of different media and lakes are clear and are related to the population density, antibiotic doses, source scales, etc. However, studies on the antibiotic contamination in aquatic environments of lakes are only the tip of the iceberg. A limited number of studies concentrate on eastern and southern lakes. In addition, studies on the residues of antibiotics and ARGs in the aquatic organisms of lakes are lacking. The usage and emission of typical antibiotics in lake basins and the rates with which they are contributed from different sources are not clear.
Acknowledgment
This work was financially supported by Ministry of Science and Technology of China (Grant No. 2015FY110900).
Introduction
Antibiotics have been extensively used for several decades to protect human health, decrease disease, and promote the growth of livestock and poultry [1]. Since most antibiotics are water-soluble, as much as 30–90% of the parent compounds used can be released into the environment through discharge via feces and urine [2], posing potential risks to human health and ecosystems. Antibiotics have frequently been detected in soil and wastewater, especially those associated with concentrated animal feeding operations [3]. High concentrations of tetracyclines (TCs) have been detected in most soils receiving long-term manure application [4]. The residues of antibiotics in soil have been reported to reach as high as 1079 mg kg−1 chlortetracycline (CTC), 2683 mg kg−1 oxytetracycline (OTC), and 105 mg kg−1 TC with the application of manure containing antibiotics [5].
Moreover, antibiotic resistance genes (ARGs) are considered to be emerging environmental contaminants [6]. Antibiotic resistance has already been identified as one of the top three threats to global health by the World Health Organization [7]. As a result, antibiotic-resistant bacteria (ARB) and ARGs have attracted increasing international concern in recent years. Although there are few studies on ARB, it has already confirmed that they still exist even in locations where a certain antibiotic has not been detected [8]. According to recent reports, most ARGs show higher relative abundance in wastewater lagoon than in manure, even after treatment [9]. Also, elevated diversity of ARGs has been reported in the receiving environment, including natural water and field soils [10,11].
The reviewed half-life values for TCs are >20 days in soil [12,13]. However, Tang et al. [4] and Chen et al. [8] reported no significant difference between previously and currently wastewater-irrigated soils or manure-based fertilizers as long as the antibiotics were used once. Also, antibiotics and ARGs still remained at an elevated level two months after application of organic fertilizer, and the relative abundance of ARGs in most soils did not differ significantly between the first application and a repeated application [11]. Therefore, remediation should be carried out as soon as the pollution occurs and efficient treatment should be urgently developed to mitigate the pressure caused by the antibiotics as well as ARB and ARGs in the environment. Currently, investigations have been carried out on the reduction of antibiotics and ARGs in the resource utilization of animal wastes [14,15], as well as in the process of wastewater treatment [16–18]. However, few studies have reported on countermeasures for antibiotics, ARB, and ARGs already existing in soil.