Tackling pollution to provide clean drinking water for all
Experts are trying to develop new, innovative techniques to treat water contaminated with arsenic and fluoride
Not just air, water pollution is also a major concern with most water bodies being used as dumping sites for industrial waste, untreated sewage and even solid waste matter, making water largely unfit for drinking and a health hazard.
Several studies have shown how water pollution remains a global challenge, especially chemical contamination.
A World Bank report , Quality Unkown: The Invisible Water Crisis, released in August this year, using a vast database on water quality, showed it would be nearly impossible to meet the global targets set to save the deteriorating environment by 2030. Failure to meet the targets will eventually have an impact on the overall health, economy, education, and so on, of all countries.
The 193 United Nations (UN) member-states agreed on September 25, 2015 to a 15-year target of 17 sustainable development Goals (SDGS), with 169 targets aimed at helping everyone live healthier, more prosperous lives on a cleaner planet.
SDG 6 refers to clean water and sanitation for all, but the UN World Water Development Report found about three out of 10 people - 2.1 billion - did not have access to safely managed drinking water at home in 2015. India was no different, with many parts of the country reporting water contamination due to arsenic, mercury, cadmium and fluoride, among others.
Arsenic contamination, especially is huge, and was first reported in 1983 from West Bengal. Since then, it has affected at least six other Indian states -Jharkhand, Bihar and Uttar Pradesh, in the floodplains of the Ganga river; Assam and Manipur in the floodplains of the Brahamaputra and Imphal rivers and Rajnandgaon village in Chhattisgarh, according to the abstract, Groundwater Arsenic Contamination in India: Vulnerability and Scope for Remedy, prepared by experts from the National Institute of Hydrology, Roorkee.
Some experts say it is a problem in the floodplains of all rivers originating from the Himalayas and the Barail range in the northeast.
Arsenic poisoning leads to symptoms such as skin diseases, liver toxicity, heart ailments, destruction of red blood cells, and even cancer.
TACKLING WATER CONTAMINATION Efforts have been made by various agencies and individual experts in devising ways to ensure safe water supply to the affected population.
Robin Dutta, a professor in the chemical sciences department at Tezpur University in Assam, has been working on a technique to remove arsenic and fluoride from water since 2005, and after five years of work, finally the technique became functional in 2010 and first tested in Assam’s Jorhat city, one of the severely affected areas in the state.
The technique was patented in 2017.
“While most other contaminants such as lead, mercury etc. are a man-made problem, arsenic and fluoride contamination is due to natural causes and affects vast areas and larger populations. We developed two methods for removal of arsenic and fluoride that are easy to make and very cheap, which makes it useful at the grassroots level,” says Dutta.
The techniques have been named Arsiron Nilogon (for removal of arsenic) and Fluoride Nilogon (for fluoride removal).
“Arsiron Nilogan is a technique wherein we create a condition that’s similar to underground water that doesn’t have arsenic by making use of catalysts such as cooking soda, potassium permanganate and ferric (iron) chloride. These are all commonly available chemicals. As a result of the chemical process that takes place by mixing these compounds together, arsenic settles on coagulated ferric chloride and can be removed through filtration technique,” says Dutta.
The basic idea behind the technique was to convert a difficult-to-remove form of arsenic to an easy-to-remove form. The cost of using the technique is as low as 1 paisa for filtering one litre of water.
The Fluoride Nilogon technique involved treating water with crushed limestone that absorbs fluoride and phosphoric acid. The contaminant in this case can also be filtered out. The cost is even lower than the arsenic removal technique at 0.4 paise to filter a litre of water.
With support from the department of science and technology for his project, Dutta is already working on expanding the technique to other states such as Bihar and Uttar Pradesh that are also grappling with water contamination.
Dr Kuttanellore Muraleedharan, director of the Council of Scientific and Industrial Research (Csir)-central Glass & Ceramic Research Institute (CGCRI), has also worked on filtration techniques that help remove hazardous contaminants from water.
“Be it arsenic, iron or other elements dissolved in water, our ceramic membrane technology is capable of purifying it with good results,” he says.
CGCRI experts developed the technology over a decade ago but it picked up only about 5-6 years ago. A filtration plant can be installed at the community level to filter water for as low as 20 paise per litre.
“It can purify everything else apart from the saline contamination for which reverse osmosis (RO) technique is good enough. There have to be slight modifications done before installation based on the type of contaminant in water. The device can stay active for 6-7 years,” said Dr Swachchha Majumdar, a researcher at the CGCRI lab who is also part of the team that developed the technology.
The institute has tied up with a manufacturer and takes orders for installation of the plant at its laboratory. “It is our indigenous product and our laboratory takes the orders,” he added.
Dr Muraleedharan says, “There is a huge need to come up with innovative techniques for water purification that are affordable for masses at the ground level as water contamination is a major issue in India.”
When seventh grader Gitanjali Rao, then 11, heard about the problem of lead contamination of water in the state of Michigan in 2017, she decided to do something about it. The result was Tethys, a portable device that detects lead in drinking water. Rao won the Discovery Education 3M Young Scientist Challenge’s America’s Top Young Scientist award of 2017 for her invention.
How does your innovation work?
I have created a portable testing device that checks for lead contamination in water. I named it Tethys after the Greek goddess of fresh water. The gadget is capable of indicating presence of lead in as quickly as 15 seconds. It has a testing probe on the side that needs to be dipped in water for a few seconds, after which it should be connected to a cellphone through Bluetooth to get the readings.
The device is not very expensive as it does not cost more than $20 (approximately ₹1,400), including the research cost. It costs $5 (₹350) for a test.
How did you think of coming up with this testing gadget?
I learnt about the lead contamination problem in the state of Michigan. It disturbed me to know that kids my age were drinking poison every day; and it was water that they were drinking. Soon, I learnt that it was an even bigger issue in countries like India and Brazil and people do not even know about it to take any action. It was a worldwide problem and access to clean drinking water is our right.
I knew then that I was going to look for a solution to this problem and hence detection became my primary focus.
What happens next?
I am participating in events to generate awareness about the issue, the need for testing and the device in general. Apart from that I am also looking at partnering with an incubator (start-up) company to help me with the mass production of this device that will further bring down the cost, so it is affordable for all especially utilities and households.
What do you plan to major in?
I definitely want to get into engineering, most likely biomedical engineering, genetics. I could also opt for biochemistry and continue in the field of research. As you can see, I change my mind within seconds.
What inspired Tethys?
The device is similar to gas sensors based on carbon nanotubes that are used to detect levels of hazardous gases in the air. My device is also sensors based on nanotechnology. It was the inspiration and started out as a broad idea that had to be narrowed down. A lot of hard work and research went to developing the device about two years ago.
Can you take us through your