Cambodia’s use of pesticides has not contaminated the country’s drinking water supply, preliminary findings from a recent chemical survey indicate.
But the same survey, conducted by the Ministry of Rural Development in cooperation with the World Health Organization, has shed light on a new potential threat to Cambodia’s drinking water—arsenic.
The survey tested over a hundred drinking water samples in 13 provinces for 46 different pesticide compounds.
Among all these samples, only a few slight pesticide traces turned up.
“There was virtually no pesticide residue in any of the drinking sources we sampled—that even includes rivers,” said Steven Iddings, an environmental engineer at the WHO who was instrumental in the survey.
“I don’t want to say that pesticides are not a problem in the country—but they have not leaked into the drinking water we used in our samples,” Iddings added.
The ministry survey did, however, pick up traces of arsenic in about 9 percent of the drinking water points sampled, all of them sanitary wells with hand pumps. These traces exceeded the WHO’s 10 parts per billion guideline for safe quantities of arsenic.
But officials say there is no cause for alarm.
“We don’t see [arsenic] as an immediate public health threat,” Iddings said Thursday. “We don’t want people to think ‘My God, Arsenic!’ and then run in fear…to their certainly unsafe surface water sources.”
Cambodia’s most serious water-related health problems still spring from contamination by human and animal feces in surface drinking-water sources.
“Deep-well water is still the safest drinking water source, compared to the water people take from ponds, streams, rivers and cisterns,” according to Ly Thuch, secretary of state for the Ministry of Rural Development.
The detection of arsenic in Cambodia’s drinking water supply is a fresh complication in an already troubled state of affairs.
In a country of roughly 11 million people, 7 million live without access to safe drinking water, according to Ly Thuch, who suggested the ministry conduct a survey of drinking water.
Since the 1980s, NGOs have been building sanitary wells with hand-pumps in the provinces, because protected well water lacks the fecal matter and bacteria that make most Cambodians sick.
At present, 15 percent of Cambodians have access to sanitary wells with hand pumps.
In the 1990s, Bangladesh experienced a serious arsenic-related disaster due to an abundance of wells in the country and a failure to detect widespread arsenic contamination until far too late, according to Michael Chommie, of Partners for Development.
In 1972, there was one well for every 400 people in Bangladesh. Wells built in the 1960s and ’70s directly led to several deaths in the 1990s, because arsenic’s detrimental effects appear only after years of continued exposure, Chommie said.
Some of Cambodia’s wells are arsenic-contaminated, the new ministry survey indicates, but they are more recent wells—meaning people have had less exposure to potential contaminants—and are not as plentiful as the Bangladeshi wells were. Because arsenic contamination tends to be highly localized, the majority of wells in an area may be safe even if one well is contaminated, Iddings said.
Cambodia is about to embark on a more rigorous study of arsenic in its groundwater, he said.
“We don’t know what the extent of the arsenic is—that will be our next step,” Iddings said. “Cambodia is very fortunate to have found it at this stage.”
When the results of the drinking water survey are fully assembled sometime in September, the ministry will invite all stakeholders in the rural drinking water problem to discuss a plan of action. Then the ministry will arrange a governmental inter-ministerial meeting, including the Ministries of Health and Environment, according to Ly Thuch.
Meanwhile, ministry officials and the WHO still believe biological contamination in surface drinking water sources is a much greater threat than arsenic, and deep well water is still the safest source.
“The answers to most of Cambodia’s health problems are ordinary hygiene, cleanliness and using the cleanest water possible,” Iddings said. “And right now, sanitary wells with hand pumps provide the cleanest water possible.”