Ni 汀ate Contamination of Groundwater and Its Countermeasures

Th e inevitable increases of food production and energy consumption with an increase in world population become main causes of an increase of ni 住ate load to the environmen t. Although ni 甘ogen is essential for the growth of animal and plant as a constituent element of protein ， excessive nitrate load to the environment contaminates groundwater resources used as drinking water and leads to seriously adverse e仔ects on the health of man and livestock. In order to c1 arify the problem of nitrate contamination of groundwater and search a new trend of technology development from the viewpoint of environmental remediation and protection ， the present paper has reviewed adverse e仔'ects of nitrate on human health ， the actual state of ni 町ogen cycle ， several kinds of nitrate sources ， measures for reducing nitrate level ， etc.