Australian scientists have developed a new water filter that can cheaply and easily filter arsenic out of drinking water. The technology it uses, however, isn’t something you’d normally think of putting in your drinking water: the filter utilizes on a mix of algae and bacteria to convert arsenic into a less toxic and less soluble form that makes it easier to extract. This new process could be especially useful in developing countries, where arsenic poisoning runs rampant.
Image © Mark Sadowski
In the past, scientists have used costly chemicals to convert the arsenic. However, bacteria from soil contaminated with heavy metals can naturally reduce the toxicity of arsenic without the high price tag and undesirable side-effects. The only problem is that the bacteria require a constant source of carbon to stay alive. That’s where the algae comes in. It grows when exposed to sunlight and creates a steady stream of carbon and oxygen that feeds the bacteria. The bacteria, in turn, breaks down organic matter and contaminants into carbon dioxide that feeds the algae.
Researchers are currently studying this new filter to determine if it could be a practical solution for unsafe water in individual households or even entire villages. Unfortunately, arsenic poisoning remains a worldwide problem that contaminates the groundwater of over 70 countries, including the US and parts of Asia and South America. Long-term exposure to arsenic through drinking water or food can cause intestinal issues, cancer, heart disease, and even death.
Lead image © Malcolm Manners