The organic pollutant monitor measures the concentration of organic pollutants such as factory wastewater from the absorbance of ultraviolet rays. Conventionally, a mercury lamp was used as the light source for UV absorbance measurement, but the new "OPM-161L" uses an LED lamp. We will contribute to the reduction of environmental impact in line with the Minamata Convention. In addition, by adopting an LED lamp, the size and weight of the detector have been reduced and the life of the detector has been extended. You can improve maintainability and reduce the man-hours required for maintenance work. It can be used for monitoring pollutant loads related to total water quality regulations and managing various wastewater concentration regulations.