Hyperkeratosis, or extreme pigment change, typical of arsenicosis.

S ix Cambodian provinces and parts of Phnom Penh have been found with unhealthy quantities of arsenic in the water pumped from tube wells, and the symptoms of arsenicosis have been reported on villagers in Kandal and Prey Veng provinces, government officials said in a meeting late last month.

Many tube wells, or bores, have been drilled in rural areas in the past couple of decades as part of aid development projects. They can be drilled up to 100 meters deep; traditionally dug wells seldom reach 20 meters.

Dr Kol Hero, deputy director of preventive medicine at the Ministry of Health (MoH), said health officials tested 219 villagers in Prek Russey village in Kandal province's Koh Thom district.

The results found that 34 villagers, or 16 percent, had visible evidence of arsenicosis, and that perhaps as many as 80 percent were suspected of having the poisonous chemical in their bodies. Many were found to have the telltale lesions of hyperkeratosis, or extreme pigment change, on the skin of their feet, hands and chests.

"It is not confirmed that the people are infected with arsenic, as the laboratory results have not come out yet," Hero said. "But according to the symptoms, 80 percent of those tested had arsenic disease."

Officials from the Ministry of Rural Development (MRD) and MoH, working with technical assistance from Unicef and the World Health Organization (WHO), conducted arsenic investigations in 162 villages in six provinces - Kandal, Kampong Cham, Prey Veng, Kampong Thom, Kampong Chhnang and Kratie - and in some parts of Phnom Penh. The results are expected to be completed in 2007.

Dr. Chea Samnang, director of rural health care at the MRD, said arsenic is a chemical element found in groundwater roughly 50 meters beneath the surface. People who use tube-well water from this depth may be subject to arsenic problems.

"Arsenic does not appear in all tube wells' water; it depends on the soil and the condition of the well," Samnang said. "We are concerned that many other provinces may be affected by arsenic."

Samnang said 40 percent of villagers in Prek Russey village displayed symptoms of arsenic poisoning. He said tactics to mitigate the disease include not drinking arsenic-tainted water, eating multi-vitamin food and vegetables, using antibiotics and stopping smoking.

"If we do not treat it over time, it will cause skin cancer or urinary [kidney] disease," he said.

A baseline survey and clinical examination of arsenicosis among exposed populations in 817 households in Kandal province, conducted by the preventive medicine department of the MoH from October to December 2003, showed that during the wet season 40 percent of the families use rainwater as their main water sources.

More than half of the remaining households use tube-well water as the main drinking water source throughout the year. During the dry season, the proportion of households using tube-well water increased to 83 percent. The survey found that 4 percent use surface water from lakes or rivers, and others used bottled water.

Samnang said an Arsenic Inter-Ministerial Sub-Committee was founded in 2002 after officials identified symptoms of arsenic poisoning in some provinces.

Phan Sophary, water and environmental sanitation officer at Unicef said about 15,000 wells in 13 provinces have been tested and that seven provinces are believed to be blighted with arsenic. Arsenic cannot be seen and can be discerned only through chemical analysis.

"We have educated villagers not to drink or cook with water if arsenic is found, but they can use the water for washing clothes or bathing," Sophary said. "Arsenic poisoning will show symptoms within five to 10 years."

Samnang said the MRD has called on provincial chiefs of rural development to report to the ministry every three months, as it is their duty to educate people about the dangers of arsenic and they must conduct extensive tests before new wells are dug.

When selecting an alternate source of water to avoid arsenic, Samnang said it is important to remember that rivers, lakes, open wells, and even rainwater, can have dangerously high levels of bacteria and viruses. These water sources must be treated or boiled before drinking.

Minister of Rural Development Lu Lay Sreng said that many people get ill from unsanitary water -for example, diarrhea and intestinal worms- and Cambodians spend roughly $12 million each year on medicine to combat the ailments.

"The ministry has developed a policy to supply clean water and sanitation to 100 percent of rural areas by 2025, but I suggest that by the year 2015 we should provide clean water to at least 70 percent of rural areas," Lay Sreng said.

He said Cambodian people living overseas donate more than $1 million per year for developing the rural areas.

Unicef's Rodney Hatfield confirmed that arsenic contamination has been identified in the Mekong river basin. Kandal province is known to be severely affected by arsenic contamination of groundwater.

"Arsenic is a cumulative poison and the onset of symptoms are slow but inevitable," Hatfield said. "Children will be the most exposed and the most at risk."

Mao Saray, director of the rural water supply department at the MRD, said only 31 percent of rural Cambodians presently have access to clean water. The MRD aims to supply untainted water to 50 percent of countryside residents by the year 2015.