Name: A device to detect lead in water by a 13-year-old innovator | Gitanjali Rao | TEDxGateway
Uploaded: 2025-05-03T03:20:21.000Z
Duration: 11 min 3 s
Description: Thousands of YouTube videos with English-Chinese subtitles! Now you can learn to understand native speakers, expand your vocabulary, and improve your pronunciation...

Transcriber's Name Reviewer's Name In 2002, a mechanic from Uberaba, Brazil, was tired of frequent power cuts in his town.

So, Alfredo Moser took a plastic soda bottle, filled it with water, added a bit of bleach to keep the water clean, put a black cap on it, and stuck it out on his roof.

Participle clauses

Used for years in deck prisms on ships, the external light dispersed enough to give him brightness in the room, equivalent to a 40 to 60 watt light bulb.

This simple solution is now used in millions of homes around the globe.

Ali Shahbaz, a marketing executive, created the lifesaving dot to help solve the problem of iodine deficiency in women in India.

The symbolic bindi is now also a source of iodine.

And there are many more other amazing inventions.

Innovation doesn't need a big R&D budget and a lot of resources.

It needs the genuine drive and motivation to make a difference in our communities.

I'm 13 years old, and I like to find solutions to real-world problems.

I'm also an active promoter of science, technology, engineering, and math.

I write and speak in schools and forums like these to help socialize the idea of STEM.

Some of my works and innovations have garnered recognition, and I'd like to share some of what worked for me with others.

Today, I'll be talking about innovation and the process of thinking differently.

To make it a bit real, I'd like to walk you through some of my latest work and tell you a personal story about a device I created to detect lead in drinking water.

I'd also like to take this opportunity to talk about the role of all of us in promoting science and technology, especially the importance of girls joining and staying with scientific research and engineering.

Let me share with you how I went about creating my device to detect lead in water.

My journey has been about tackling one of the main challenges we face today, that is access to clean drinking water.

The state of water in India today is that mercury, arsenic, and cadmium are the top metallic compounds in water that is harmful.

Increasingly, due to aging pipes and lax standards, lead is also becoming one of the most harmful contaminants in our water supply.

Health effects of lead in water can range anywhere from birth defects to serious health issues, which can even lead to death.

Unfortunately, there aren't a whole lot of solutions to easily test for lead in drinking water.

My parents couldn't do it easily, and there are entire cities like Flint, Michigan, in the U.S., where lead contamination affected many of its residents, especially children.

So I decided to create a device to detect lead in water.

My solution addresses the core issue of speedy detection, helping people take preventative measures and maybe even saving lives.

It uses the latest developments in nanotechnology, is easy to use, fast, accurate, portable, and inexpensive.

MIT and others have been working on using carbon nanotubes, a special form of carbon structure known for its connectivity properties as gas sensors.

Detecting a chemical contaminant like lead, especially in a liquid medium, required a different approach than current techniques.

And using an emerging technology like carbon nanotubes seemed like a logical and promising solution.

I named my device Tethys, after the Greek goddess of fresh water.

Tethys consists of a core device with a processor, a Bluetooth, inbuilt Bluetooth and a power source, a disposable lead sensor cartridge, and a smartphone that displays the results.

When I dip this cartridge into the water I want to test, the lead in the water binds with the chloride ions doped within the carbon nanotubes in the disposable cartridge, forming lead chloride molecules.

This increases the amount of resistance to the flow of current and decreases the conductivity.

The conductivity drop is correlated to the severity of lead compounds in water.

So, I've made it easier for the user by adding an Adafruit processor to measure all resistance and current values.

And with inbuilt Bluetooth, it sends the data to your mobile phone, which displays results of either safe, slightly contaminated, or critical.

Today, I'm unveiling the latest version of my device, which I designed and printed myself.

The device is now 60% smaller and over 300% more power efficient.

I'm using the latest communication protocol and controller, which significantly reduces the power needs of this device.

I've also updated the software to operate like an IoT sensor, so it crowdsources device data and stores it in a central database, which it then can be transferred for analytics and heat maps.

I've open-sourced my sensor analytics code as well as my Android app, and it's been downloaded and used for a few other projects as well.

To improve the accuracy of my carbon nanotube sensor, I'm trying with other dopants, such as fluoride and iodide.

At an R&D phase, the device costs about 1,300 rupees, with the cartridge costing around 30.

I'm on track to bringing the price of the device down to 300 rupees, with the cartridge at around 10 rupees.

I've secured some funding from investors, and with my own prize money, I hope to get the device out there soon.

We've all heard about innovation and know a bit about it, but let me share my definition of it.

I look at innovation to be the continuous process of building and learning.

Broadly, my principles of innovation are understand and relate.

Understand, recognizing, and relating to the problem is the first step.

When I innovate, while learning science and technology is great, I prefer to look at what's already been done first.

Build something quickly, even if it's with Lego or cardboard boxes.

I like to build first, even if it starts out being very basic.

This might mean going back to step three.

Development is intended to be a repeated process.

I've used this process in many of my other devices, such as an Asclepias, a snakebite diagnostic tool, using non-contact thermography technology, and SalasChat, a cyberbullying prevention chat interface, using machine learning.

I hope these ideas can help spur innovation in others.

Change needs all of us, and science needs all of us, including girls.

Unfortunately, statistically, there are fewer girls in STEM fields, regardless of the country we live in.

While around 80% of the jobs in the future will require STEM skills, only around 10% of girls show interest in STEM fields in high school.

I increasingly find myself alone in science projects, engineering, and programming camps.

This certainly isn't due to the lack of capability in girls.

All indications seem to be the lack of motivation and support.

Without girls getting excited about innovation, the problems of today and tomorrow can never be solved.

I'm doing my small part by partnering with the Children's Kindness Network and running STEM combined with kindness sessions for elementary schools.

I've provided research opportunities at universities, internships, and lab space at Denver Water.

Somebody believed in me and invested in my research.

An incubator is guiding me with commercial feasibility, and most of all, my schools and teachers have provided me with problem-based learning.

Without their support, I wouldn't be here today.

It needs companies and individuals that foster independent thinking, even if they are a bit unconventional.

We deserve an education system where we're judged on our ability to solve problems and learn from failures, and not just on our ability to get good scores.

I'd like to request one thing from each of you.

It would be that you seek a mentee and mentor them in the areas that they are passionate about.

In addition, we can help by volunteering our time for the development of sciences, raising funds, and promoting awareness.

Innovation will continue to drive change and develop the world.

Our generation is growing up in a place where we're seeing problems that have never been seen or have never existed before, and we need to be a part of that change.

India is a nation where women played a huge role in sending a satellite to Mars, but only around 14% of researchers are women.

With the right focus, attention, and all of your help, India can lead the world in scientific innovation.