The Weight of Water

ME Professor Creates Mobile Nitrate Sensor

Professor Gartia using the Mobosens tool to test water.BATON ROUGE – LSU Mechanical Engineering Assistant Professor Manas Gartia sets two vials of water on the table. One is dirty with sediment floating in it. The other has clear water. “Which one would you rather drink?” he asks.

The answer seems apparent but perhaps it’s not as clear as the seemingly harmless vial of water. What Gartia is trying to demonstrate could save lives—clear water is not always clean water.

Since 2013, Gartia has been working with a team of researchers to develop an ion contaminant sensor, named MoboSens, that will detect nitrate and phosphate levels in water around the world, starting in the United States.

“The point of the project is if water is dirty, you won’t drink it,” he said. “But if the water is clear, you wouldn’t think twice about drinking it. What if I tell you the clear water has a very high concentration of phosphate and nitrate or lead? The point is all the contaminants are invisible to the naked eye, which is why we need to have something that can detect these individual contaminants.”

Of course, there are already facilities that test drinking water, but Gartia is looking to help people with wells, farmers, fishermen, travelers, military, first- and third-world citizens, and even water-testing plants themselves.

“Traditionally, how we do testing is we send some samples off to a lab, then they give you results,” Gartia said. “However, it’s costly for regular labs that test for ion contaminants to send samples back and forth. Currently, $1.1 billion is spent on water quality monitoring, $3.4 billion on swimming pool equipment and testing, and $1.3 billion on precision farming.”  

What makes Gartia’s creation unique is that it would allow for mobile testing, which is quick and cost-effective. Though one in nine people across the world don’t have access to clean water, half of the global population has a mobile phone. Gartia figured, why not create a free mobile phone application that would allow users to test their own water?

After downloading the MoboSens app to a mobile phone, there is a plastic box, or “package,” that connects to the phone via an audio jack. The colorimetric nitrate-nitrite strip is placed on a sensor holder that attaches to the package, which is resistant to moisture, static, and shattering. Within minutes, one can collect a water sample, test it on the sensor and read the results on the strip. The results can be shared on Twitter and saved in iCloud. The sensor would not cost more than $50 and is lightweight, impact-resistant, and has optical clarity.

The idea for MoboSens came from a desire to help people in a disaster zone connect with one another. When an acquaintance of Gartia visited Guatemala through Engineers Without Borders, she relayed to him the problem people had with accessing drinkable water.

“Since there were no water-testing devices, they had to ship all of their water to the U.S. to test,” he said. “It was not cheap. She asked if they could have something portable and low-cost to give to the countries that don’t have access to instruments.”

Besides helping people in undeveloped or disaster areas, MoboSens would be beneficial to those living off of well water, as well as farmers who could test their soil for nitrates.

“About 45 million Americans use well water that is not regulated by the EPA [Environmental Protection Agency],” Gartia said. “That means it’s up to them to test their own well water. If they think something is wrong, they test every year or two, not very often. With MoboSens, they can test as often as they’d like.”

Two water vials, one dirty and one clear.Gartia added that there is a high risk for people with well water who live near crops because the fertilizer can run into their system, contaminating it. Farmers who use MoboSens would be able to test their soil for nitrates by mixing it with water to create a sample. This would prevent them from having to visit the field to collect samples and cut down on the amount of fertilizer needed for planting.

And if nitrates in farmed food don’t seem like a concern, Gartia said to consider blue baby syndrome, among other illnesses.

“Babies develop a condition called blue baby, where hemoglobin is not able to absorb oxygen, a direct cause of excessive amounts of nitrates in drinking water,” he said. “The condition is found mostly in the Midwest, where people are using nitrates to grow corn.”

Not only do 3.4 million children die each year worldwide from water-related illness, but U.S. fishermen lose $82 million annually due to harmful algal bloom, according to Gartia.

“Another problem is the nearly 9,000-square-mile dead zone in the Gulf of Mexico caused by algae,” he said. “Nitrates and phosphates coming through the Mississippi River cause the algae to grow, taking oxygen from water, killing fish and anything living. Algae should be created so fish can eat but the problem is overgrowth of the algae. When the algae dies, there is bacteria that will feed on the algae and produce toxins in the water. Even a small amount of this toxin can be neurodegenerative.”

Reports suggest that in 2008, the Mississippi River/Gulf of Mexico Hypoxia Task Force said the dead zone would decrease. That number, however, has steadily increased over the years.

“This will be a problem to the fishing industry,” Gartia said. “It will be a crisis.

“The idea was how we can measure local concentration of this nitrate and phosphate and how we can connect this with global concentration,” he added. “NASA has many satellites that can take pictures of these large water bodies. So, if we can measure this concentration in local water bodies and connect that to the NASA pictures, then we have a correlation between how this local contamination would affect the Gulf of Mexico.”

Gartia said that until laws are in place to protect water sources, contaminated water will be a problem. In the meantime, people will be able to protect themselves using MoboSens.

Initially funded by the National Science Foundation, the MoboSens project now has multiple sponsors and is an award-winning idea. Gartia and his team won second place in the Vodafone Americas Foundation Wireless Innovation Project category, earning the team $200,000. They also placed in the top six in the international XPrize Nokia Sensing Challenge, where they won $120,000.

Though the MoboSens device will be of great use worldwide, there are still some kinks to work out.

“Before we sell it, we need to make sure it’s very reliable,” Gartia said. “Once you sell it and it doesn’t work or has a problem, you’re done.”

As for making a huge difference in people’s lives should MoboSens be a success, Gartia said, “The smartphone-integrated sensor will provide a personalized solution for a global problem to ensure access to clean water. If nothing else, it will create awareness.”

Watch a video of how MoboSens works.


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Contact: Libby Haydel

Communications Specialist

225-578-4840 (o)