Ultra-sensitive optical sensor system for simultaneous, in-situ detection of multiple pesticides in surface and ground waters

In recent times, our climate has been undergoing significant changes, resulting in extreme weather events such as floods and droughts. Unfortunately, these events can led to an increase in the presence of pesticides in our water systems, posing potential risks to various aspects of our environment and economy. The existing methods for testing water quality are not sufficiently rapid in identifying these issues. The STARDUST project is focused on developing an innovative monitoring tool using advanced technology called surface-enhanced Raman spectroscopy integrated with microfluidics. This technology acts as a rapid-response tool, allowing us to quickly detect and analyze the presence of pesticides in both surface and groundwaters. In addition to technological advancements, STARDUST will use rainfall forecasts to optimize sampling schedules. This involves engaging citizens in the collection of water samples during periods of significant rainfall, offering valuable insights into the correlation between extreme weather events and water quality. The collected data, including the identification of pesticides and their concentrations, will be made accessible to the public. Our goal is to ensure transparency and enable informed decision-making regarding water safety and quality. In a world where climate uncertainties are becoming more pronounced, the STARDUST project stands as a critical initiative to fortify our water quality monitoring capabilities. By combining cutting-edge technology with strategic collaboration and community involvement, we strive to safeguard the integrity of our water resources.

Hydro-climatic extremes, such as droughts and floods, have increased due to climate change and could lead to severe impacts on socio-economic, structural, and environmental sectors. Soil water assessment models have shown that pesticides are transported into waterways because of intense rainfall events. Current monitoring methods are not suited to the detection of such water quality impacts, which can deplete invertebrate populations and impact biodiversity and ecosystem health very rapidly. Many surface- and groundwaters are used as sources of drinking water, and therefore the occurrence of chemicals is problematic for water treatment facilities. Rapid, real-time sensing technologies do not exist yet but are urgently needed to address this. The STARDUST project aims to develop a first-of-its-kind, integrated optical system combined with smart spectral data processing methodology, for multiplexed monitoring of pesticides in surface and ground waters, and to understand the impact of extreme hydroclimatic events on water quality in the context of pesticide occurrence. We will develop a sensor based on surface-enhanced Raman spectroscopy fully integrated with microfluidics targeting the detection of pesticides, pesticide mixtures, and metabolites in surface and ground waters. Secondly, we will use rainfall forecasts to identify sampling times for passive sampling and citizen scientist co-created events, to gather samples that are specifically linked to rainfall events. This will build on existing monitoring programmes, but, more critically, will identify the climate-related water quality impacts. The results of passive sampling will identify target pesticide compounds to be addressed with the developed novel sensor and a database of detected pesticides will be compiled and shared publicly.