Nitrate concentrations

Spatial distribution of nitrate concentrations. A total of 59 samples (or 13%) show concentrations above the limit of 50 mg/l given by the WHO. Pollution has different sources. In the north of 12° latitude north, pollution is thought to be the result of animal faeces from livestock watering directly from the borehole. In the south, pollution is due to agricultural use because of excessive application of nitrogenised fertilizers Source: BGR