Groundwater pollution in Pakistan

Abstract Groundwater is a major freshwater resource in Pakistan. However, overextraction and other anthropogenic pressures have led to contamination of this valuable resource. Numerous studies have reported four major tribulations of groundwater contamination in Pakistan: bacteriological, arsenic, nitrate, and fluoride. Bacteriological contamination is mainly due to leaching of municipal wastewater. It is the leading cause of gastrointestinal disorders and child mortality in Pakistan. Arsenic is classified as Group 1 human carcinogen. Pakistan ranks fourth globally among the arsenic-affected countries globally. Rural Sindh and Punjab are worst affected areas with arsenic pollution. Fluoride is responsible for skeletal and dental fluorosis. Districts Quetta, Lahore, Kasur, Gujrat, Swabi, Nagarparkar, and Umerkot have been reported with excess fluoride in their groundwater. Presence of nitrate can be attributed to agriculture activities and leaching of sewage water. Punjab and Balochistan provinces have highest reported nitrate concentrations. Metals such as zinc, lead, nickel, and iron have also been reported in various parts of the country, which are briefly discussed in the chapter along with the major anions.