Introduction. Environmental contamination with pesticides causes negative impact on soil, water, and whole ecosystems. Studies evidenced links between pesticides and diseases such as Parkinson’s, prostate cancer, immune depression, allergies, and others in population groups heavily exposed to pesticides. Chronic exposure to low levels of pesticides also raises toxicity concerns. Persistent organic pollutants (POPs) are a class of very dangerous pollutants, capable of long-range transport, bio-accumulation in human and animal tissue, and bio-magnification in food chains. In such an exposed environment almost everyone has POPs in their body, including newborns or even embryos. Highly accessible analytical platforms for fast, selective and decentralized detection of dangerous chemicals are therefore of very high demand.

Objectives. Within this project we propose to develop sensing platforms able to detect environmental pollutants by simultaneous optical spectroscopy and electrochemistry. A nanostructured plasmonic chip will be the core of the spectro-electrochemical sensor combining the advantages of highly specific and sensitive surface enhanced Raman spectroscopy (SERS) to the versatility, portability, and low costs of electrochemical (EC) sensing. The dual SERS-EC sensing platform will be integrated in a microfluidic system, in order to benefit from reproducible measurements due to highly defined environment, easy handling of small sample volumes, high throughput detection, and even sample preparation and mixing procedures in continuous flow. Additionally, a second dual sensing cell based on common spectrophotometer cuvettes, for ml-scale sample volumes will be developed. The proof of concept will be demonstrated on organohalide pesticide endosulfan, an emerging pollutant (EP) selected from the new POPs list of the Stockholm Convention and the JRC Watch List. Extending the adaptability of the proposed sensing platform to the detection of other environmental pollutants (e.g. lamda-cyhalotrin, thiabendazole) will be also pursued. Our research aims to provide sensing platforms by which these substances can be detected in surface waters samples and also to contribute to the scientific data regarding POPs accumulation and distribution. The design and experimental development of the SERS-electrochemical sensor aims for device portability for field (in-situ) applications, such as monitoring EPs in surface waters at critical sites (e.g. in the vicinity of a possible pollution source).

Approach. To overcome the involved scientific and technical challenges and achieve the proposed objectives, a diverse range of expertise, skills and infrastructure capacities are combined: optical simulations and experiments, nanofabrication, microsystems technologies and microfluidics, advanced characterisation tools, plasmonics, surface enhanced Raman spectroscopy, DFT calculations, electrochemistry, gas chromatography, chemometric tools. The proposed consortium is a highly trained and experienced one, relatively young, and with a very good gender balance. No ethical issues implying human or animal testing are raised by the implementation of this project.