One of the major challenges in environmental control is at present the monitoring of air and water quality as a prerequisite effectively controlling and counteracting pollution and enforcing new more stringent legislation. This requires highly selective, sensitive, fast, and low-costs sensors for efficient pollution monitoring. Many pollutants including hydrocarbons, oxides of nitrogen and sulphur generated through the combustion of fossil fuels, exhibit strong absorption lines in the Ultra-Violet (UV) spectral range which allows optical techniques to be used for rapid, sensitive and contactless gas sensing and monitoring exploiting this wavelength range. Spectroscopic optical sensing offers a range of significant advantages over other sensor concepts such as high selectivity and specificity, high sampling rate, real-time and on-line monitoring, as well as the capability of stand-off sensing and detection. Among the different available optical sensors, fiber coupled systems are most promising due to their compactness and robustness, inertness to chemical or electromagnetic interferences and multiplexing capabilities. In this project, we propose to develop a practical electrically-injected RC-LED emitting in the 380-400 nm range build on a epitaxially grown AlGaN/GaN DBR underneath an active GaInN/GaN MQW active region. The top DBR will be based on UV-transparent dielectric oxide layers. Specific variations in device design will allow to adjust the device emission wavelength to match the precise emission wavelengths for specific application, such as the absorption lines of the different polluting gases. The availability of such RC-LEDs coupled to an optical fiber for relaying the UV-light as well as for sensing will be of strong interest for spectroscopy community where European companies and research laboratories are strongly involved.