Wells designed to provide rural Cambodians with water free of bacterial contamination have brought arsenic into the drinking supply in areas along the Mekong River and its tributaries, government and UN officials said this week.
Now the Ministry of Rural Development, in conjunction with the UN Children’s Fund, has begun to address what both say is a serious, but manageable, threat.
Detectable only through chemical tests, arsenic can cause many types of cancer and diseases of the liver, skin, blood and brain.
David Fredericks, a technical adviser at Unicef, said about 5,000 wells already have been tested. A comprehensive Unicef report on arsenic is scheduled to be finished by the end of July, he said.
Unlike bacteriological contamination, in which people can perceive a link between ingestion and sickness, Fredericks said, arsenic education is more difficult because a person can drink the water for years without feeling any effects. Thus, some of the $375,000 Unicef provided last week for fighting arsenic contamination will go toward educating villagers about the more mysterious menace.
As a preventive measure, Mao Saray, director of rural water supply at the Ministry of Rural Development, said some wells in highly contaminated areas have been painted red “and we advise [residents] to use rainwater or water in ponds and lakes.”
Some wells dug by the government and NGOs tapped underground water supplies where organic matter had used up the available oxygen, creating arsenic. Though a similar effect was observed in Bangladesh in the mid-1990s, it is not common, he said.
According to the Unicef statement, arsenic is only a threat to 1,400 villages, primarily in Kandal province.
Fredericks said arsenic is an “unintended consequence” of fighting bacterial contamination, which remains a greater threat than arsenic, by building more wells. When the wells were dug, “people didn’t know about the arsenic,” he said.
(Additional reporting by Van Roeun)