Traditionally, the 25 million Vietnamese people living in the Red River Delta and Mekong Delta area that have no access to public water supply have been using river surface water for drinking and other daily usage.
Due to pathogen-contaminated surface river water, they developed symptom of cholera, dysentery and other infection diseases. To combat these diseases, in 1980, UNICEF encourage the digging for private tubewells in VietNam. Currently, there are over 1,000,000 tubewells in operation and the numbers are rapidly increasing.
Just like the dilemma (calamity) in Bangladesh, water from tubewell dug in Vietnam was also found contaminated with high level of arsenic.
An article published by Swiss Federal Institute for Environmental Science and Technology in 2001:
This is the first publication on arsenic contamination of the Red River alluvial tract in the city of Hanoi and in the surrounding rural districts. Due to naturally occurring organic matter in the sediments, the ground waters are anoxic and rich in iron. With an average arsenic concentration of 159 μg/L, the contamination levels varied from 1 to 3050 μg/L in rural groundwater samples from private small-scale tubewells.
In a highly affected rural area, the groundwater used directly as drinking water had an average concentration of 430 μg/L. Analysis of raw groundwater pumped from the lower aquifer for the Hanoi water supply yielded arsenic levels of 240−320 μg/L in three of eight treatment plants and 37−82 μg/L in another five plants. Aeration and sand filtration that are applied in the treatment plants for iron removal lowered the arsenic concentrations to levels of 25-91 μg/L, but 50% remained above the Vietnamese Standard of 50 μg/L. Read more
Started since Jan 1999 to Jul 2003, water from well samples, rivers and lakes collected from North to South of Vietnam were analyzed in Weck Environmental Laboratories, Industry, CA, a state certification analysis laboratory (accredited laboratory). 22 metals, 70 organic compounds and 7 anions were analyzed with an accuracy of one part per billion (ppb or ug/L) for the first two groups and one part per million (ppm or mg/L) for the following groups.
Average arsenic concentration in groundwater from different areal segments sorted by distance from the Mekong River. Data were collected from the literature (Buschmann et al.,2007,2008; Nguyen and Itoi,2009; NWD, 2014; Papacostas et al., 2008; Sthiannopkao et al., 2008). Studies indicated the further from the river, the lower level of arsenic contamination.
The higher than normal arsenic content in Mekong Delta acid sulfate soil Jon Petter Gustafsson of the Groundwater Research Group (GRAG), Sweden and Mr. Nguyen Thanh Tin of the Vietnam Water Quality Monitoring Network (WQMN) who conducted solid phase analysis of Mekong Delta acid sulfate soil (ASS) reported that arsenic content in Mekong Delta ASS is 10-30 mg/l or 2 to 6 times higher than normal soil arsenic level.
Arsenic pollution of groundwater in Vietnam exacerbated by deep aquifer exploitation for more than a century
Arsenic contamination of shallow groundwater is among the biggest health threats in the developing world. Targeting uncontaminated deep aquifers is a popular mitigation option although its long-term impact remains unknown. Here we present the alarming results of a large-scale groundwater survey covering the entire Red River Delta and a unique probability model based on three-dimensional Quaternary geology. Our unprecedented dataset reveals that ∼7 million delta inhabitants use groundwater contaminated with toxic elements, including manganese, selenium, and barium. Depth-resolved probabilities and arsenic concentrations indicate drawdown of arsenic-enriched waters from Holocene aquifers to naturally uncontaminated Pleistocene aquifers as a result of >100 years of groundwater abstraction. Vertical arsenic migration induced by large-scale pumping from deep aquifers has been discussed to occur elsewhere, but has never been shown to occur at the scale seen here. The present situation in the Red River Delta is a warning for other As-affected regions where groundwater is extensively pumped from uncontaminated aquifers underlying high arsenic aquifers or zones.
Arsenic Distribution in the Red River Delta.
The distribution of groundwater As concentrations is illustrated bellow. Arsenic concentrations were found to vary greatly throughout the delta (< 0.1 - 810 μgL) and 27% of the wells exceeded the WHO guideline value of 10 μgL. Our results imply that some three million people are currently using groundwater burdened with As concentrations >10 μgL and one million people use groundwaters containing > 50 μgL, with both rural and urban populations being affected by toxic levels of As. Arsenic concentrations in groundwater collected in the period from 2005 to 2007.
The arsenic problem in Vietnam is real and has only got worse. Professor Nguyen Khac Hai, chairman of the National Institute of Occupational and Environmental Health's Science Council of Vietnam, said that studies conducted over the past 20 years found significant arsenic contamination in groundwater in the Red River and Mekong deltas.
"Recent tests found concentrations of arsenic in groundwater in An Giang and Dong Thap [in the Mekong Delta] up to hundreds of times higher than the recommended level," he told Thanh Nien Weekly.
So far, he said, no effective treatment has been discovered and the best way to prevent harmful health effects is to cease the use of tainted water for everything from bathing to drinking.
"Ceasing the use of arsenic-polluted water is the best and only way to prevent contracting related diseases or worsening one's condition after contracting such an illness," he said.
Easier said than done. Of the 25 million Vietnamese people living in the Red River Delta and Mekong Delta areas that have no access to public water supply, they simply don't have a choice.
At We All Care, volunteers with different background around the world are joining hands. And only then, it may enabling us to come up with a more effective solution.
2003 - Asen trong nước uống
2006 - Magnitude of arsenic pollution in the Mekong and Red River Deltas
2008 - Arsenic in Drinking Water – Vietnam, New Focus of Attention
2009 - University of Denmark - Groundwater arsenic in the Red River delta
2009 - Arsenic plagues wells throughout Vietnam
2014 - Arsenic exposure to drinking water in the Mekong Delta
2014 - Assessing Health Risk due to Exposure to Arsenic in Drinking Water
2015 - Arsenic plagues wells throughout Vietnam -Thanh Nien Daily