Currently, water samples must be transported to a laboratory to reveal pollution. But new sensor technology is enabling researchers to measure pesticides in the water on site – and get the results right away.

By Mari Mortvedt - Published 01.09.2026

Extreme weather events, such as floods, droughts and torrential rains, affect the water quality in lakes, rivers and coastal areas. This creates significant challenges for ecosystems and water supplies, because pesticides that are bound in soil masses can quickly leach into water sources. Now researchers want to monitor this in a new way.

“Today’s monitoring systems aren’t equipped to detect rapid variations. This leaves critical gaps in environmental protection and public health preparedness. The goal of the project, called STARDUST, is to develop an optical sensor system that can detect multiple pesticides in real time in both surface water and groundwater,” says Elizaveta Vereshchagina, a senior research scientist in SINTEF’s Department of Smart Sensors and Microtechnology, Norway.

The technology will provide insight into how extreme weather affects the occurrence of pesticides in water. It is being developed with interdisciplinary collaborators from Norway, Romania, Poland, Ireland and Denmark.

Engaged citizens in Denmark and Ireland

When researchers want to examine water samples after heavy rainfall, they need to collect the samples immediately. This is logistically challenging. STARDUST has therefore engaged citizen scientists in Denmark and Ireland, who collect water samples during periods of significant rainfall.

These water samples are important for gaining insight into the connection between extreme weather conditions and water quality.

“We create references at our site and also have the samples sent to Oslo, so that we can test our sensor technology in the laboratory. We’ve managed to measure different types of pesticides in water using SERS technology, which provides a fast response. The hope is that we can physically bring this type of sensor technology to water sources in the future," says research colleague and project leader Karolina Milenko.

SERS stands for Surface-Enhanced Raman Spectroscopy technology. The method boosts light signals from molecules, making them easier to measure. SINTEF combines SERS with microfluidics, where the samples flow through small transparent channels. Together, these methods provide fast and accurate analysis in real time.

What to know about SERS sensors and microfluidics:

Advances in nano- and microtechnology have made it possible to develop advanced optical sensors and to integrate them with microfluidics to control water samples more quickly.

• Technologies like UV nanoimprint lithography, deep reactive etching (DRIE), glass microstructuring and wafer bonding provide high precision in the dimensions that are important for obtaining robust sensors.
• At SINTEF, both SERS substrates and microfluidic components are designed and manufactured in clean rooms. Despite significant progress, technological challenges related to SERS substrates and measurement methods remain.
• Miniaturized microfluidic SERS platforms are now used for testing under controlled laboratory conditions, where test parameters can be adjusted systematically, and researchers can both simulate field work and vary the quality of the water samples.

“It can be challenging to distinguish between different pesticides at low concentrations in our datasets, partly due to different backgrounds in the samples. In the STARDUST consortium, we have expertise that helps us achieve better sensitivity using artificial intelligence,” says Vereshchagina.

Rapid changes should be measured in real time

Sudden changes in water quality threaten both biodiversity and the safety of drinking water. Because it is challenging to measure the water sources’ varied contents, the current solution is to transport water samples to the laboratory for testing. When natural disasters or extreme weather occur, such changes can happen very quickly, and therefore monitoring should take place in real time.

“Imagine a landslide in a river high in a valley. This landslide can quickly contaminate the water in the river, but it is difficult to measure. We hope our technology can provide real-time measurements, showing how different pesticides move with the water. This may also make it possible to implement preventive measures before contaminated water does too much damage,” says Hans-Jørgen Albrechtsen, a professor at the Technical University of Denmark (DTU) and partner in the project.

The project’s interdisciplinary consortium consists of experts in nanotechnology, photonics, micro- and nanofabrication, materials science, machine learning-based signal processing and environmental chemistry. One of the things that makes STARDUST unique is that the measurement takes place in miniature, on a very small microchip. In the future, the researchers hope to develop a machine the size of a rolling suitcase, which can be taken with you and take measurements directly in rivers, groundwater and lakes.

Facts about STARDUST:

The STARDUST project is coordinated by SINTEF in Norway, which has extensive experience in developing micro-optical sensors integrated with microfluidics. SINTEF’s expertise includes UV nanoimprint lithography and 3D patterning methods.

• STARDUST is funded by the EU and the Research Council of Norway through the European partnership Water4All.
• SINTEF is also responsible for ensuring that the results are integrated with water management after the end of the project. The goal is to use microsensors to strengthen resilience in increasing climate pressures.
• Partners are the: National Institute for Research and Development in Microtechnologies (Romania), the National Institute of Materials Physics (Romania), the Institute of Physical Chemistry, the Polish Academy of Science (Poland), Dublin City University (Ireland), the Technical University of Denmark (Denmark) and SINTEF (Norway).
• SINTEF has experience from several industrial projects related to microfluidic technologies for water filtration.

More information about the project can be found on this website: https://water4all.ro/stardust/