Water Quality Microbes are filtered from water that percolates into groundwater. Some pathogens are transmitted to human in drinking and recreational water. Resistant chemicals may be concentrated in the aquatic food chain. Mercury is metabolized by certain bacteria into a soluble compound,concentrated in animalsWater Quality • Microbes are filtered from water that percolates into groundwater. • Some pathogens are transmitted to human in drinking and recreational water. • Resistant chemicals may be concentrated in the aquatic food chain. • Mercury is metabolized by certain bacteria into a soluble compound, concentrated in animals