Analysis and identification of pesticides and their transformation products in groundwater by High Resolution Mass Spectrometry

Nowadays it is increasingly important for public policy to know what compounds are present in groundwater, which of them must be monitored and their fate . Thus, specific analytical methodology is required to identify these micropollutants, including emer ging substances or transformation products (TPs) potentially present at low concentrations. To improve limit of detection , POCIS (Polar Organic Chemical Integrative Sampler) were used as passive samplers for the pre - concentration of polar compounds. High Res olution Mass Spectrometry (HRMS) offer ing the possibility of detecting a large number of contaminants without pre - selection of analytes due to its accurate - mass full - spectrum acquisition was also applied . The combination of these two techniques carried out o n s everal groundwater sampled monthly confirms the advantage of i) improvement of organic chemical screening with POCIS and ii) identification of non - targeted organic compounds with HRMS technique. Several p esticides and some of their transformation products were detected for the first time in these sites .