| Antibiotics have been widely used in disease treatment and livestock production for decades,and played an important role in promoting animal growth and improving the quality of livestock products.The persistence of antibiotics in the environment not only selectively inhibits environmental microbes,but also induces the production of some resistant bacteria and resistance genes,resulting in their special ecotoxicological effects,which ultimately indirectly endanger human health.Since only a small part of these antibiotics are metabolized in humans and animals,most of them are directly excreted in the form of metabolites from urine and feces,and can enter into the water environment through medical pharmaceutical sewage,domestic industrial sewage,livestock and livestock waste water,etc.At present,the sewage treatment plant lacks the deep removal and degradation equipment of antibiotics,which causes the antibiotics to even have a higher concentration than the influent water,when the water is dischar ged.In addition,direct disposal of different types of waste water can also cause circulating pollution of antibiotics.In order to reveal the distribution characteristics of typical antibiotics in the water environment of Bazhou?mainly Kaidu River,Bosten Lake,Kongque River?,this paper aims to detect the concentration levels of antibiotics in the main r ivers,lakes,upstream and downstream environmental waters,and analyze their distribution characteristics.Provide a basis for evaluating the ecological and health risks of antibiotics.The main conclusions are as follows:?1?There are three kinds of analytical methods for 13 kinds of antibiotics,such as quinolones,sulfonamides and tetracyclines,Pretreatment techniques of water were established such as solid phase extraction and liquid chromatography tandem mass spectrometry?UPLC-MS/MS?.The accuracy of the pretreatment and the accuracy of the test method verified that the method can easily,quickly and accurately analyze the residues of various antibiotics in the water environment.?2?The existence of 13 antibiotics in the surface waters of the Kaidu River,Bosten Lake and Kongque River in the samea as basin of Bazhou was investigated.The results showed that the detection frequency and concentration of enrofloxacin were highest in all samples.Geographically,Kaidu River,Bosten Lake and Kongque River are located in the upper,middle and lower reaches of the Kaidu River-Bosten Lake-Kongque River,respectively.The spatial var iation of antibiotic pollution level is“U”type;from the time horizon,Taking the water-rich period and the dry season as the research objects,the time-varying trend of antibiotic pollution levels in the three water environments was first high,then low and then high,showing a"U"shape.?3?The concentrations of antibiotics detected in the water of the Kaidu River-Bosten Lake-Kongque River Basin during the wet and dry periods were ND92.62ng·L-1?DC?and ND350.96ng·L-1?ENR?,respectively.The total concentrations of antibiotics in the sampling points of Kaidu River,Bosten Lake and Kongque River were ND165.58ng·L-1?SMR?,ND92.62ng·L-1?DC?,ND350.96ng·L-1?ENR?respectively,seasonal differences are significant,with quinolones?QNs?and tetracyclines?TCs?antibiotics as the main pollutants.?4?The main contributor of quinolones1?QNs?antibiotics is enrofloxacin1?ENR?,with an average residual concentration of 18.42 ng·L-1.The antibiotic level of the Kongque River is higher and peaks at the sampling point K9.In space,it is represented by the downstream Kongque River section>the upstream Kaidu River section>the middle Bosten Lake section,which has certain correlation with aquatic animal husbandry and population distribution.The main contributor to tetracycline?TCs?antibiotics is doxycycline?DC?,with an average residual concentration of 16.05 ng·L-1.In time,it is characterized by a wet season>dry season.The detection rate of enrofloxacin and doxycycline is higher.?5?Through the investigation of key pollution sources around the water environment in Bazhou,the sources of 13 antibiotics in the natural waters of Kaidu River,Bosten Lake and Kongque River were preliminarily determined.The results showed:sulfadiazine?SDZ?,sulfamethoxazole?SMP?,sulfamethazine?SMD?,sulfamethazine?SMR?,sulfathiazole?STZ?and chlortetracycline?CTC?,doxycycline?DC?,lomef loxacin?LOM?mainly comes from aquatic livestock and poultry breeding sources;ciprofloxacin?CIP?and oxytetracycline?OTC?mainly come from sewage treatment plants;tetracycline?TC?mainly comes from livestock and poultry farming;Sand star?ENR?and norfloxacin?NOR?are mainly from aquaculture.In summary,through the spatial distribution of typical antibiotics in rivers and lakes in the Bazhou region during the wet and dry periods,it is found that the distribution of antibiotics in the wet season is more obvious.From the geographical location of the upper,middle and lower reaches,the antibiotic pollution in the Bosten Lake section The situation is lighter than the upstream Kaidu river section and the lower Kongque River section.The downstream peacock section is susceptible to surrounding pollutants.The concentration of sulfonamide antibiotics is not correlated with the surrounding pollution sources,and the ENR and DC antibiotic residual concentrations are high.Exposure to obvious ecological r isks,this study is not only important for the ecological risk management and pollution prevention of antibiotic pollutants in the water environment of Bazhou,Xinjiang,but also helps to supplement the environmental distribution of such pollutants. |
PDF Full Text Request