Distribution Characteristics And Transportation Behaviour Of Antibiotics And Antibiotic Resistance Genes In Refuse Degradation Process

Antibiotics is widely used for human and animal health,releasing large amounts antibiotics into environment.Antibiotics and antibiotic resistance genes(ARGs)pose risks on environment.Antibiotics and antibiotic resistance genes enter the environment by leachate,causing environmental problems.Refuse is the main medium for antibiotics and antibiotic resistance genes to enter the environment.However,the dynamics of antibiotics and ARGs along refuse decomposition remains unknown.In this study,8 kinds of antibiotics(tetracyclines: tetracycline,oxytetracycline,chlortetracycline;sulfonamides: sulfadiazine,sulfamerazine,sulfamethazine;macrolides: erythromycin and roxithromycin)and the related 5 kings of ARGs(sulfonamides antibiotic resistance genes: sul?;tetracycline antibiotic resistance genes: tetO,tet W;macrolide antibiotic resistance genes: ermB,mefA)in refuse and leachate along refuse decomposition was investigate.The finding can provide theoretical basic for antibiotics and ARGs transplantation in landfill.The main conclusions are as follows:(1)In this study,the degradation of refuse in the simulated reactor was aerobic,anaerobic acidification and methane production.Although the increase in antibiotics residues in refuse will not prevent the degradation of refuse,but will affect the rate of refuse degradation,resulting in column B of refuse degradation rate was significantly lower than the column A.(2)Antibiotics and antibiotic resistance genes are prevalent in refuse.Three kinds of antibiotics: oxytetracycline,tetracycline and roxithromycin were detected in the column A.The detection rate of the five target antibiotic resistance genes in the collected samples and leachate samples was 100%.(3)The increase in antibiotic residues in the refuse can strengthen the distribution of antibiotics in the solid-liquid phase behavior and migration behavior.The antibiotic in the column A did not show solid-liquid distribution and migration behavior.The target antibiotics were detected in the solid-liquid phase samples of column B.The migration behavior of the three kinds of antibiotics in the process of waste degradation occurred in the space: upper sampling layer> middle and lower sampling layer> leachate;The concentration of antibiotics varies with the passage of time.The solid-liquid two-phase distribution is characterized by the fact that the content in the solid phase is higher than that in the liquid phase.(4)In the process of refuse degradation,the relative abundance of genes in the solid-liquid phase is at the same level.Although the increase in antibiotic residues did not affect the distribution of relative abundance of the gene in the solid-liquid phase,but the effect of the relative abundance of the gene was affected.The relative abundance of ermB gene in the solid phase sample of column A was significantly higher than that of column B,and the relative abundance of tetO gene was significantly lower than that of column B in column A.In the A column the relative abundance of the target gene ermB and mefA in the liquid sample was significantly higher than that in the B column,and the relative abundance of the gene sulI was significantly lower than that in the B column.(5)In the process of refuse degradation,BDM% in column A affected the tetracycline and the organic matter affected oxytetracycline.BDM% in column B affected sulfadiazine and sulfamethazine;Organic matter and ammonium nitrogen affect roxithromycin.There was no significant correlation between antibiotic resistance gene and antibiotic in column A,but the antibiotic resistance gene was positively correlated with TN,organic matter and nitrate nitrogen,and the antibiotic resistance gene was negatively correlated with temperature.There was a significant correlation between antibiotic resistance gene and antibiotic in column B,and the antibiotic resistance gene was positively correlated with nitrate nitrogen,ammonium nitrogen and organic matter.In the A and B column refuse and leachate physical and chemical properties,antibiotics between antibiotic resistance genes have different characteristics,not only reflects the refuse degradation process of material changes in the complexity,but also reflects the complexity of the three related.