Correlation Analysis Of Asthma Drugs And Air Quality Based On The Wastewater Epidemiology And Their Photolytic Behavior And Mechanisms

Asthma is one of the most common chronic diseases in the world and there are almost300 million people suffering from asthma,including 30 million in China.And researches thought that with the worse air pollution,this number for asthma was still growing.Limited to the time-consuming and high cost of traditional epidemiological research,there are some unique advantages of Wastewater Based Epidemiological（WBE）in indicating people’s living habits and health behaviors.The principle of this method is that after the drugs were ingested by the human body,it would be excreted in its original or metabolite form after being metabolized,then flow into the wastewater treatment plant（WWTPs）with the domestic sewage.Combining the influent flow and the population of the service area,the concentration of residual drugs or their metabolites in the sewage can be used to calculate the discharge amount,and the per capita consumption of certain drugs in the area could also be obtained.Therefore,asthma was choosed as the research drugs and asthma drugs were as the target drugs.Through a one-year period collection of influent samples from two WWTPs in Guangzhou,the ouccrance of asthma drugs in WWTPs was explored and the consumption of asthma drugs was estimated based on the WBE.The air quality and meteorological factor in the area during the sampling period were collected to explore the correlation between the consumption of asthma drugs and air quality.At the same time,in order to prevent the harm effects from asthma drug residues to ecosystem,the transformation and removal technology of typical asthma drugs in acquatic environment had been studied.And the final research results were as follows:（1）Due to the microbial degradation,suspended particulate adsorption,Salbutamol（SAL）was attenuated during the sewer transportation;and for salmetetol,the microbial degradation and hydrolysis was the main reason for losses.And microbial degradation dominated the attenuation.The maximum attenuation of SX was 43.0%,while SAL was only 19.8%.So when SAL and SX was choosed as the indicators of asthma diseases,it’s necessary to consider the loss part during sewer transportation.（2）In WWTP1 and WWTP2,SX was not detected,and the average concentration of SAL were 84.90±160.53 ng?L^-1and 51.63±36.11 ng?L^-1,respectively.The real-time population of WWTPs service area calculated by per capita sewage discharge was close to the actual population.Then combined with the sewer looses,the SAL per capita consumption of WWTP1 and WWTP2 were 64.38±81.33 mg?（d?1000 person）^-1and 44.05±32.48 mg?（d?1000 person）^-1,respectively.However,according to the analysis of Pearson’s correlation coefficient,there was negatively correlated（p<0.01）between SAL consumption and air quality in WWTP1.As for WWTP2,there was no significant correlation（p>0.05）.（3）Under 365 nm UV irradiation,the photolysis rate of SAL and SX conformed to the pseudo-first-order kinetic equation and ¹O₂dominated the SX photolysis process（41.7%）.The increase of temperature,p H value and the presence of HCO₃^-and NO₃^-promoted the photolysis of SX while the initial concentration of SX and Cl^-showed promotion first and then turned to inhibition.FA inhibited photolysis by the effects of optical screening and free radical scavenging.Nine intermediates and three possible transformation pathways were predicted through UPLC-Q-TOF analysis.Based on the luminous intensity test of photobacterium phoshoreum T3 spp,the toxicity of the final reaction system was reduced,decreasing the toxic potential of the intermediates.