Overview

Around the world, there are at least two billion people who lack access to safely managed clean drinking water. But the discovery of a “metal-eating” bacteria has given scientists hope of removing some of the life-threatening contaminants from water. The result? Polluted water can be transformed and made safe for human consumption. The breakthrough was achieved by scientists at the School of Biochemical Engineering, IIT-BHU, who succeeded in removing toxic hexavalent chromium from wastewater. The work was published in the Journal of Environmental Chemical Engineering.

The science and other stuff to know

Hexavalent chromium is a known carcinogen. It can cause cancer in the nasal tract, sinus, kidney, and liver. Continued exposure to the compound may also result in nasal and skin irritation, ulceration, eye irritation, and infertility.

Researchers Dr. Vishal Mishra and Ph.D. student Veer Singh conducted a study on wastewater samples collected from a drain in Madhya Pradesh, where coal mining units discharge their wastewater after treatment. They discovered that a new bacterial strain — named Microbacterium paraoxydans strain VSVM IIT(BHU) — isolated from the wastewater could remove hexavalent chromium from contaminated samples effectively. 

What’s more, it does so in an eco-friendly manner.

Dr. Mishra said the strain was “very effective” for the removal of hexavalent chromium from wastewater compared to other conventional methods. “This bacterial strain showed fast growth rate in the Hexavalent chromium– Cr (VI)– containing aqueous medium and gets easily separated from the aqueous medium after the treatment process,” he said in an interview with Hindustan Times.

So what?

While the discovery of the strain was made in India, the toxic hexavalent chromium is not endemic to India alone. It’s commonly found in chemicals that are used in the world’s largest industries. Need some examples? It’s used in textile dyes, wood preservation, anti-corrosion products, paints, inks, plastics, and more. 

And untreated or undertreated wastewater with traces of the chemical often makes its way into the food and drinking water supply. The presence of hexavalent chromium traces in groundwater in California is an ongoing health concern.

What’s next

Given the widespread presence of hexavalent chromium contaminants in wastewater around the world and the high probability of this untreated water making its way into rivers and reservoirs supplying human populations with drinkable water, the discovery of Microbacterium paraoxydans strain VSVM IIT(BHU) is nothing short of a scientific breakthrough. 

If fully developed and deployed, it could save millions of people from life-threatening diseases. Moreover, Dr. Mishra stated that the efficient and eco-friendly manner in which the isolation of contaminants could be achieved might offer a renewed impetus to the industrial sector to employ better wastewater treatment methods. 

Further research is needed in both of the aforementioned areas to make them a reality.