Current Status Of Microplastics In Tianjin Coastal Waters Of And Its Effect On Penicillin Potassium Adsorption And Photonolysis

Microplastics and antibiotics as new environmental pollutants have the characteristics of wide source distribution and strong potential danger.Microplastics in the environment often adsorb pollutants such as antibiotics in the environment due to their special surface properties.The environmental behavior and toxic effects will not be underestimated.This paper selects the coastal waters of Tianjin as the research area,and the seawater,sediments and typical organisms in the coastal waters of Tianjin were collected by fixed-point sampling method.In addition,two common microplastics,polyethylene(PE)and polystyrene(PS)are selected,with penicillin potassium as the target antibiotic,the adsorption of penicillin potassium by two kinds of microplastics is studied by setting the concentration gradient for isothermal adsorption experiment.The ultraviolet light is used as the illumination source to investigate whether microplastics affected its photolysis behavior.The study found:The average abundance of micro-plastic surface seawater and sediments in the coastal areas of Hangu,Tanggu and Dagang in Tianjin is 612/m³ and 20/100g.The main types of micro-plastics are PET,PP-PE and EP.The deposits are PET and PA.,PP,the average abundance of organisms(Shrimp,snail,and barracuda)were 2.19/g,0.94/g,and 1.57/g,respectively,while the organisms were mainly plastic materials and seawater and sediments.In agreement.The particle size distribution in the surface water and sediment is mainly less than 5 mm,while the organism is evenly distributed in the range of less than 5 mm,(0.5-1)mm and more than 1 mm,the type is mainly fiber and debris,in blue and Black dominated.The results of PE and PS adsorption of penicillin potassium are more consistent with the nonlinear Langmuir adsorption model.The adsorption effect in pure water is PE>PS,while in seawater,the contrast is found in different background solutions.The adsorption capacity is pure water>seawater.The photolysis of penicillin potassium by PE and PS showed that the photolysis of penicillin potassium is consistent with the first-order kinetic degradation process under different background solutions.The degradation rate is K_blank>K_PE>K_PS,degradation rate seawater>pure water.From the experimental results,PE and PS have an inhibitory effect on the photodegradation of penicillin potassium,and PS has a stronger inhibitory effect on penicillin potassium.