Effect of chemical nitrogen fertilizer application on the release of arsenic from sediment to groundwater in Bangladesh

The effect of chemical nitrogen fertilizer application on groundwater arsenic pollution was examined. Arsenic and N concentrations in peat sediment were high. In the groundwater, a high arsenic concentration was observed under a high ammonium-N concentration with reducing conditions. From _15N analysis, the source of N in peat sediment and groundwater was possibly chemical N fertilizer. Thus, we assumed that a high N environment created by the fertilizer led the groundwater to reducing conditions through the enhancement of microbial activity, and the reducing condition promoted the arsenic release from peat sediment to the groundwater.