Pollution Analysis And Potential Risk Assessment Of Typical PPCPs In Reclaimed Water

With the acceleration of economic development and urbanization,water environment pollution is becoming more and more serious and water resources are becoming increasingly scarce.Reclaimed water is widely used in agricultural irrigation,landscape water and aquifer recharge.Reclaimed water reuse can alleviate the pressure of water supply,but due to the limitation of the existing process of sewage treatment plant,some toxic organic pollutants,such as drugs and personal care products（PPCPs）,can not be effectively removed,resulting in their eventual entry into the environmental media,long-term exposure to biological and human health potential hazards.PPCPs are frequently detected in reclaimed water,which is one of the important factors causing reclaimed water reuse risk.In this paper,the pollution characteristics of 17 typical PPCPs in water and the removal efficiency of typical PPCPs by water treatment process are studied,and the risks of typical PPCPs to the health of aquatic animals,plants and people are assessed in the process of reclaimed water reuse.The research results provide technical support for wastewater treatment and reclaimed water reuse,and provide theoretical basis for environmental protection and public health.Seventeen typical PPCPs in sewage were selected as research objects,including anti-inflammatory and analgesic drugs,antibiotics,broad-spectrum antibiotics,hormones and so on.A method for the determination of typical PPCPs in water samples by solid phase extraction-high performance liquid chromatography-mass spectrometry was established.The recovery of typical PPCPs was 60%¹10%,and the detection limit was 0.1¹.63ng/L.The concentration of typical PPCPs in the influent and effluent of a reclaimed water treatment station in Xiamen was monitored.The concentrations of 17 PPCPs in influent ranged from ND to 5485.0ng/L.The concentrations of Acetaminophen（ACE）and caffeine（CAF）were the highest,with the average concentrations reaching1784.5ng/L and 1622.0ng/L.The detection rates of 12 PPCPs in influent were 100%.The detection rates of typical PPCPs in effluent ranged from ND to 279.0ng/L.The detection rates of Antipyrine（ANT）,Diclofenac acid（DF）,indomethacine（IND）and mefenamic acid（MA）in effluent were 100%（N=10）,and the highest concentration was 17α-Ethinylestradiol（EE2）（84.0ng/L）.With the seasonal change,the typical PPCPs concentration in the intake water of the reclaimed water station changes.The total PPCPs concentration in summer is more than twice that in winter.The removal efficiency of Acetaminophen（ACE）and caffeine（CAF）by reclaimed water treatment process is better,98.06%and 97.28%respectively,and the removal efficiency of Carbamazepine（CAR）is poor,even the effluent concentration is higher than the influent concentration.Biological process is the key unit to remove typical PPCPs.Disinfection process has certain removal effect on 17α-Ethinylestradiol（EE2）and Sulfamethoxazole（SMX）.The environmental risk assessment results of typical PPCPs in mid-water showed that four substances which included 17α-Ethinylestradiol（EE2）,Estrone（E1）,Sulfamethoxazole（SMX）and Triclocarban（TCC）had high risk to aquatic organisms,four substances which included Acetaminophen（ACE）,Diclofenac acid（DF）,Ibuprofen（IBP）,Triclosan（TCS）had moderate risk to aquatic organisms,and the most affected species were fish and mollusks.The higher risk factors are17α-Ethinylestradiol（EE2）,Diclofenac acid（DF）,Propylparaben（PPP）,Estrone（E1）and Gemfibrozil（GEM）.The HQ of 17α-Ethinylestradiol（EE2）is less than 10^-6,and the health risk factors of all substances are far less than 1.However,due to the changes of exposure concentration and exposure time and long-term cumulative effects,long-term exposure to PPCPs still has potential risks to biological and human health.