Contaminated groundwater endangers 60 million Pakistanis: Study

A new study has said that around 60 million Pakistani people are at risk of a variety of serious health problems including cancer due to an 'alarmingly high' level of arsenic contamination was found in groundwater beneath the Indus Plain in Pakistan.

The study, published in the U.S. journal Science Advance, examined groundwater samples collected from nearly 1,200 sites from across the country, reported Xinhua on Wednesday.

"A model incorporating topographical, geochemical and hydrological parameters was used to create the first comprehensive 'hazard map' of this poisonous element for the whole of Pakistan. It showed that many people in eastern Punjab, which includes Lahore, the country's second most populous city, are exposed to a high risk of arsenic contamination," Xinhua reported.

"In many parts of the densely populated plains along the Indus River and its tributaries, arsenic concentrations in groundwater supplies exceed the WHO (World Health Organization) guideline of 10 micrograms per liter. Very high concentrations, above 200 micrograms per liter, are found mainly in the south; the highest measured in this study was 500 micrograms per liter," the study said.

According to the study, 50 to 60 million Pakistanis use groundwater which very likely contains more than 50 micrograms per liter.

"This is an alarmingly high number, which demonstrates the urgent need to test all drinking water wells in the Indus Plain," first author Joel Podgorski, a geophysicist at the Swiss Federal Institute of Aquatic Science and Technology, or Eawag, said in a statement.

Arsenic is one of the most common inorganic contaminants found in drinking water worldwide. This metalloid occurs as a natural component of sediments, with small quantities being dissolved in groundwater as a result of weathering.

The inorganic salts of arsenic are tasteless and odourless, but highly toxic to humans. If ingested over long periods, even low concentrations, can cause damage to health, including skin disorders, lung cancer and cardiovascular diseases.

The WHO estimated that around 150 million people rely on groundwater contaminated with arsenic worldwide.