Laser-Based Sensor for Nitrate Isotope Analysis in Water Pollution Monitoring

Nitrate (NO3-) contamination in water is a worldwide environmental problem. High nitrate levels can result in adverse human health effects and eutrophication of lakes, rivers, oceans, and terrestrial ecosystems. There are several sources of nitrates, including manure, fertilizers, sewage, industrial wastewater, soil runoff, and atmospheric deposition. In order to effectively manage nitrate pollution in water, it is important to discern these contamination sources. By measuring the isotope ratios of nitrates, researchers can better determine the source of nitrate pollution and more effectively manage these sources to limit water contamination. Despite the high value of measuring nitrate isotope ratios for pollution sourcing and management, its application has been limited by difficulties associated with precisely measuring the isotope ratios. Current technology relies require extensive sample conditioning, high-vacuum, a dedicated operator, and consumable chemicals. The resulting system is difficult to operate, prone to failure, costly, and slow. The proposed SBIR analyzer will replace this conventional technology. It will be comparably accurate, significantly faster, more economical, and substantially more robust. Moreover, the unit will not require a dedicated, highly-skilled operator, thus enabling its use in a much wider range of applications (e.g. routine water quality monitoring, atmospheric monitoring stations, and environmental research laboratories).