EESS talk on "Characterizing Past and Present Environmental Impacts with High-Resolution Sediment Analysis"


Event details

Date and time 29.10.2019 12:1513:00  
Place and room
Speaker Dr Aurea Chiaia-Hernandez, is a researcher at the Institute of Geography and Oeschger Center for Climate Change Research at the University of Bern. Graduate in Chemistry (Oregon State University) with a PhD in Environmental Sciences at ETH in 2013, her research activities focus on integrating two disciplines, environmental chemistry and sedimentology. In recent years, she extended these to investigate the environmental impact of plant protection products (organic pesticides) in agricultural soils and microbial communities. At the University of Bern, she investigates organic contaminants in lake sediments and soils on the Swiss Plateau (Interfaculty Cooperation Project “One Health”). She is a member of the Institute of Geography Cluster “Environmental pollution”.
Category Conferences - Seminars
In recent decades, the demand of synthetic chemicals has reached ~300 million tons per year due to the global use in the domestic, agricultural, and industrial sectors. Chemicals released to the environment via direct sources or indirect input sources can enter natural waterways and ultimately be incorporated into aquatic sediments. Any of these chemicals that persist over time would become excellent archives of past environmental contamination, and can be used to reconstruct environmental changes over time within a catchment. While many studies have analyzed the sedimentary record of anthropogenic pollution, gaining a comprehensive picture of many pollutants simultaneously in local palaeorecords remains challenging. Therefore, in this talk, four different lakes across Switzerland will be presented to provide a comprehensive overview of contamination patterns over time in the last 100 years by means of liquid chromatography high resolution mass spectrometry (LC-HRMS) non-target (unknown compounds) screening. HRMS combined with statistical analysis help to gain a comprehensive picture of the occurrence of organic contaminants and their trends over time in lake sediments. Environmental changes recorded in the studied lakes give evidence of past and present water quality, as well as a record of management and mitigation measures. Sediments from the four lakes show signatures that clearly define the beginning of large-scale human impact around the 1950s. The results are also in agreement with other geological deposits (e.g. nutrient pollution and radioisotope fallout signals) and clearly ratify a long-lived phenomenon as was shown for thousands of profiles with steady increasing trends until today and not yet successfully targeted by environmental regulation and pollution reduction initiative. Furthermore, in this talk, I will show how temporal and spatial analysis are being used as a complementary tool in soil monitoring to prioritize pesticides as well as to reconstruct past applications and provide future scenarios in agriculture.

Practical information

  • General public
  • Free
  • This event is internal


  • EESS - IIE


Organic Contaminants Temporal Trends LC-HRMS Lake Sediments Soil Monitoring Pesticides