This paper is the result of hydrogeological survey engineering.

Objective To address global water pollution challenges and overcome the limitations of traditional laboratory detection methods, such as poor timeliness and difficulty in in-situ monitoring, this paper aims to systematically review the progress, current status, and trends of sensor technology in the monitoring of hazardous pollutants. It intends to provide systematic references and a theoretical foundation for the development of real-time, rapid, and intelligent water environment monitoring technologies.

Methods A combination of literature research and comprehensive analysis was employed. Relevant domestic and international studies from the past five years were systematically reviewed, and sensors were categorized and discussed based on their working principles and technological integration features. By analyzing typical application cases, the detection performance and applicable scope of various sensors for different pollutants were compared and evaluated, and current key technical bottlenecks were summarized.

Results Sensor technology has evolved into a diversified, high-performance landscape: Electrochemical and photochemical sensors demonstrate high sensitivity and rapid response advantages in the trace detection of heavy metals and organic pollutants; biosensors achieve high selectivity by leveraging bio-recognition elements; the application of novel materials such as nanomaterials and molecularly imprinted polymers has significantly enhanced performance; and the integration of microfluidics, artificial intelligence, and the Internet of Things has propelled monitoring systems toward integration, intelligence, and networking. However, significant challenges remain, including mitigating interference from complex aqueous matrices, ensuring long-term stability, achieving simultaneous detection of multiple pollutants, and reducing costs.

Conclusion Sensor technology has become an indispensable tool for real-time in-situ monitoring of water pollution and is in a state of rapid evolution. Future breakthroughs will rely on the development of novel anti-interference sensing materials, the construction of integrated multifunctional sensing systems, the integration of intelligent adaptive technologies, and the exploration of solutions such as low-cost and green sensing. By continuously overcoming core challenges related to selectivity, stability, anti-interference capability, and cost, it holds the promise of establishing a more accurate, intelligent, and efficient water monitoring network, enabling broader applications in the detection of harmful pollutants in water resources.