A team of scientists including The University of Western Australia has developed a computer model that can analyse and predict arsenic groundwater contamination, which can poison drinking water.
The scientists, also from Flinders University, CSIRO and the Swiss Federal Institute of Aquatic Science and Technology, believe the modelling will help improve water management strategies in affected areas.
Arsenic groundwater contamination is a huge problem globally, resulting in poisoning of groundwater used for drinking water. Symptoms of chronic exposure range from skin lesions to severe cancers. The estimated annual death toll for Bangladesh alone is nearly 43,000.
Computer modelling is an increasingly important tool for predicting when and where arsenic pollution might occur to protect humans who drink groundwater and to achieve better environmental outcomes. The research has been published in Nature Geoscience.
Arsenic is tasteless and odourless, and unknowingly consumed by tens of millions of people around the world. The contamination occurs in large parts of South and South East Asia.
If ingested over long periods it can cause serious damage to humans, even in low concentrations, causing enormous public health problems in countries such as Bangladesh, Vietnam, Cambodia, India and many more places.
Professor Henning Prommer from UWA’s School of Earth Sciences said the computer modelling could support efforts to more precisely identify the sources of arsenic pollution and better predict how fast arsenic pollution was spreading in aquifers used for drinking water production.
“The modelling can unravel which chemical and physical processes play a key role and predict the behaviour of arsenic within aquifers – including where and when pollution might occur in the future,” Professor Prommer said.
“We were using tiny measured tritium concentrations that had entered the groundwater system from the atmosphere during nuclear bomb testing in the 1960s, and its decay product helium, to reconstruct how fast and where the groundwater was moving over the last five decades.
“This type of computer modelling is an exciting development as we can consider not only the chemical reactions that cause the pollution but also how fast each of the chemicals is moving in the groundwater.
“This will allow us to make much more precise predictions on what might happen in the future. We can eventually much better plan on how we can avoid using arsenic contaminated water.”
Dr Ilka Wallis, a senior lecturer at Flinders University and lead author of the study, said the computer modelling integrated much of what field and laboratory-based researchers had learned over the past two decades.
“We used this particular field study site in Vietnam to test and further develop our computer model as our Swiss colleagues and many others had collected a lot of highly valuable data at this site over the last 15 years,” Dr Wallis said.
“It was extremely useful that we were able to test if our computer model would be capable to reproducing the complex geochemical processes that occur when arsenic is released and transported in groundwater systems.”
Caption for image: Red River near Van Phuc, Vietnam where surface water started to infiltrate into the Holocene aquifer as a result of Hanoi’s increasing groundwater abstraction.