A study of drinking water sources in Kandal province found widespread contamination from human excrement, posing a health risk to residents that likely mirrors the situation across Cambodia, the authors say.
Published last month on the website of the Journal of Water, Sanitation and Hygiene for Development, the study also documented the first recorded appearance in Cambodian water supplies of a type of cyanobacteria that can produce toxic algal blooms.
Throughout the country, 40 percent of rural Cambodians lack access to safe water sources, and more than 50 percent of rural households do not have toilets, according to experts.
The study’s tests were conducted on water samples collected in May and October of 2012 in Kandal’s Kien Svay district by academics from North Carolina State University and Resource Development International-Cambodia Water, a local NGO.
The tested samples—from wells, rain barrels, streams and other sources—all “pose at least some risk of diarrheal disease from inadequate public sanitation and human pathogenic bacteria,” the study says.
The surface water sites all contained traces of human bacteria that is often used to gauge the source of water contamination, the study says. Many surface water sites also contained microcystis, a harmful bacteria that generates toxins that can cause liver damage in humans and kill animals.
Rain barrels—large ceramic basins that collect water during the monsoon season—fared little better in the tests in spite of their reputation for being a better way to store drinking water, with some 73 percent of the basins harboring human bacteria.
The study notes that as Cambodia urbanizes, sewage and other runoffs are likely to increase, further threatening drinking supplies for the approximately 40 percent of rural Cambodians who lack access to clean water.
Ly Sovann, spokesman for the Ministry of Health, said the ministry was conducting a public education campaign across the country on the need to boil drinking water. The government also has a campaign to increase toilet use.
“We educate the people that they need to heat [water] to 100 degrees,” he said. “In the communes, we have volunteers to provide educational materials to the villagers.”
Irina Chakraborty, a project manager at local sanitation social enterprise Wetlands Work, said even small quantities of sewage can pose a risk. “Most surface water near human dwellings can be assumed to be contaminated by human or animal excrement,” Ms. Chakraborty wrote in an email.
“This is why water is treated before being distributed through a city’s drinking supply system,” she said. “The main thing we want to do is take out sewage pathogens.”
Geoff Revell, program director at local sanitation NGO WaterSHED, said clean drinking water remained a “major problem” but praised a government plan to end the practice of open defecation by 2025.
“Cambodia has increased from less than 25 percent toilet coverage in rural areas before 2010 to nearly half of all households in rural communities now owning a toilet,” Mr. Revell wrote.
Additionally, “people are now able to more easily purchase water filters and toilets in their local communities, something they weren’t able to do before.”