The Study On The Screening And Identification,pollution Characteristics And Ecological Risk Assessment Of Pharmaceuticals And Pesticides In The Wastewater Of Nanjing Industrial Area

The occurrence and potential risk of Pharmaceuticals and pesticides have been received more and more attention because of their wide varieties,extensive application,biological activity and persistency,and continue to be one of research issues of environmental problems.Ever since 1970s,articles and reports have revealed their occurrence in sediment and aquatic ecosystems such as lake、river、groundwater and seawater.The analysis of Pharmaceuticals and pesticides in sewage can help to understand their pollution characteristics and ecological health risks since wastewater treatment plant plays as an important role for sewage before discharging into environmental waters.In this study,we established a method of screening and identification of pharmaceuticals and pesticides using liquid chromatograghy-quadrupole-time of flight-mass(LC-QTOF-MS)to make the instrument analysis more efffective and sensitive.Based on the screening and full scanning of LC-QTOF-MS,we got the chemical list of tebuconazole、praziquantel、carbendazim、prometryne、azoxystrobin、buprofezin and propiconazole through Chemicals list filtering method and Chemicals library screening method.We used liquid chromatograghy-Triple quadrupole-mass(LC-MS/MS)to quantitative detect the concentration of those chemicals in all the samples.The results shows that the content of azoxystrobin is far higher than the other six kinds of materials,and it can reach 205-5421ng/L in samples of March;prometryne can also be detected and the content was up to 3113 ng/L in March;the concentration range of tebuconazole and propiconazole in inffluent and effluent water were 9.44-194 ng/L and 6.44-133 ng/L respectively;the concentration of carbendazim,buprofezin and praziquantel was between 0.05 and 96 ng/L in all the samples of three months except that praziquantel was detected over 100 ng/L in some samples of March and June.In this study,we also detected those chemicals in Yangzi River、Chu River and Yuezi River et al.nearby.Results revealed that carbendazim was in high concentration during wet season of about 20 ng/L;the concentration detected of all the seven chenmicals was between 0 to 30 ng/L.The theoretical dilution value of the get from the Digital Information System Mode was lower than the measured value.Risk Quotient(RQ)calculation was done to all the measured value of the wastewater samples,and carbendazim、Prometryne、propiconazole and azoxystrobin was found RQ>1 in some samples in which prometryne showed the highest RQ value.We took the same calculation to the water samples of the river nearby and got their RQ values.The results showed that most RQs were below 1,which means that there were no ecological risk to aquatic system.This study preliminarily explored the Qualitative screening and identification method using liquid chromatograghy-quadrupole-time of flight-mass(LC-QTOF-MS),and screened and detected 7 kinds of drugs and pesticide.In our experiment,we also measured and simulated the content of those chemicals in several rivers nearby,and made the ecological risk assessment using RQ values.The study can provide scientific basis to qualitative screening of organic chemicals in water samples and make risk assessment of human health in the future.