Translator: Ilze Garda Reviewer: Rhonda Jacobs
17.6 million people exposed,
5,000 water systems with the lead contamination issues,
and 5 million lead pipes still in the system.
We can't really talk about the state of our water
without talking about lead contamination.
How sure are you
that the water you are drinking is safe and contaminant-free?
How often do you test for lead in your water?
Why would you?
It all started two years ago
when I learned about the water crisis in Flint, Michigan.
Did you know that at peak lead levels reached about 127 parts per billion?
That's about nine times as much
as the EPA standards of 15 parts per billion.
I just couldn't accept the fact that there was a city in our country
where thousands of children my age were exposed to a poison,
causing life-long damage
to their vital organs, mental capacity, and even their normal growth,
just because they were using water in their daily lives.
Appallingly, this is not just an issue in Flint;
this is a world-wide problem, and we have to do something about it.
Each and every one of us have the right to know our water quality
and have access to clean drinking water.
I'm Gitanjali Rao, I'm 12 years old,
and I love finding solutions to real-world problems.
(Applause) (Cheers)
My journey has been about tackling one of the main challenges we face today,
which is access to clean drinking water.
And along this journey, I developed a device that detects lead in water.
Well, my story has a whole lot of science; it speaks to something much larger.
It's also a story of how we can collectively solve problems in society
and encourage science and technology.
Lead poisoning is harmful
due to lingering effects it has on the human body.
So, the younger the child, the more impact.
A child can experience birth defects and abnormal growth
with harmful levels of lead in their body.
Health effects of lead in water
ranges anywhere from just headaches and nausea
to possible seizures and even death.
When I initially thought about solving this problem,
I thought about completely eliminating lead out of water.
However, that was pretty complex;
it was like solving global warming with just one solution,
like stopping all carbon emissions.
Digging deeper,
I found that the lack of knowledge of the contamination,
and the extent of contamination, was the bigger problem,
mainly because it kept people away from finding alternatives sooner.
Then I realized
that many people still don't know about how big lead in water is
and that's when detection became my primary focus.
The current solutions in the market
are either too cumbersome, expensive, or take time.
They don't look at detection accuracy and contamination levels together.
The solutions are either test strips which are not accurate,
or is sending your water to your local water facility,
which is inconvenient, expensive, and takes time.
I then realized that to solving problems
my approach was a little bit unconventional.
In fact, now that I think about it, I'm a bit unconventional.
I'm 12 years old, and I love reading MIT's websites.
So instead of taking a problem and then breaking it down
and then analyzing the individual portions,
I like to play with the problem and the solution simultaneously.
And instead of completely reinventing a device from scratch,
I like to look for the tools that already exist,
and see if I can enhance or modify upon them
to potentially solve problems.
I then learned that MIT and others
have been working on using carbon nanotube-based sensor technology
to detect hazardous gases in the air.
Then I decided that I wanted to expand this idea to apply for liquids as well,
to detect lead in water.
Due to the complexity of detecting lead, especially in a liquid medium,
this required a radically different approach
from current techniques out there today,
and using an emerging technology like carbon nanotubes
seemed like a pretty logical extension and a promising solution.
So I decided to build one.
This is "Tethys" -
the quick and accurate tool to detect lead in water.
It's based on carbon nanotube sensor technology,
it's easy to use, fast, accurate, portable, and inexpensive.
Let me show you how it works.
"Tethys" consists of three parts:
a core device housing a processor
with a Bluetooth extension and a 9-volt battery,
a disposable lead sensor cartridge
that attaches to the core device and forms a circuit with a processor.
This disposable lead sensor cartridge
includes specially treated carbon nanotubes with chloride ions.
However, I had to use a buckypaper form of carbon nanotubes
due to the nature of my medium.
And the last component is a smartphone
that can connects over Bluetooth to display results.
Let's say the water here has lead in it.
Again, this disposable lead sensor cartridge
with the chloride doped carbon nanotube
has specifically armchaired single-walled carbon nanotube.
When I dip this in the water I want to test,
the lead in the water binds with the chloride ions in the nanotube,
forming lead-chloride molecules,
increasing the amount of resistance to the flow of current
and decreasing the conducitvity.
The conductivity drop
is correlated to the severity of the lead compounds in the water.
And to make it easier for the user, I added an Arduino processor
to measure all resistance current and current values,
and a Bluetooth extension to send all the data to your mobile phone
on a custom app that I created,
which gives you results of either safe, slightly contaminated, or critical.
(Applause) (Cheers)
Wouldn't it be awesome
if every household and school had a Tethys to detect lead in their water,
and test for it once a month?
Then we wouldn't have to hear
heart-breaking stories about cities like Flint
where lead poisoning and lead contamination
has affected a whole generation.
I'm continuing to work on evolving my device even further.
I'm happy to unveil to you the latest version of my device.
It is more compact and also has better sensor usability.
I also recently received investment funding.
(Applause) (Cheers)
So what I'm planning to do is make sure
that the carbon nanotube-based sensor is more accurate
by trying with other dopants such as fluorine and iodine.
Both of these ions have a very strong affinity to lead,
but not to many other compounds in water,
so that it won't result in false positives or false negatives.
Therefore I'm hoping that this will be more accurate
than the chloride-doped carbon nanotube sensor.
So I've been partnering with Denver Water and other water facilities
in order to perform my testing,
since skill testing continues to be one of my primary focuses.
In the future, I hope to see my device operate like an IoT sensor,
crowdsourcing device data for analytics and civic planning.
So,
my journey to solving problems doesn't stop here.
To summarize, Tethys is a device that detects lead in water
faster than current techniques out there today,
and not only detects lead in water, but also gives you contamination results.
So, I'm not just stopping at Tethys.
I'm also volunteering and writing articles
to spread more awareness about the water quality issue.
So I mentioned my journey, and I've shared my story with all of you,
but truly, I wouldn't be here
without the mentors who have guided and supported me along the way.
I started as a determined 11-year-old girl with an idea,
and because of the support I received,
I stand before you as a 12-year-old giving a TEDx talk about my invention.
(Applause) (Cheers)
Innovation needs support, it needs mentors,
it needs companies that foster innovation, even if they're a bit unconventional.
I would like to take this opportunity
to thank my mentors for taking the time and energy to support me,
and I hope many others benefit in the same way.
Lastly, I'm a girl in STEM.
This by itself -
(Applause) (Cheers)
This by itself shouldn't mean much,
however, I have found girls in STEM increasingly rare.
As a society, I believe this is unacceptable.
I am determined to change this.
(Cheers)
Thank you.
I've devoted my time, some of my prize money,
and I've partnered with Children's Kindness Network
in order to start STEM education programs combined with kindness.
Both of these together
can help make the next generation make the world a better place.
And I believe that we should aspire to solve bigger problems.
I'm 12, and I want to make a difference.
And I believe that the purpose of science is to make a difference.
Science needs all available hands and intellects to come together
and to solve the problems of today and tomorrow.
It needs all of us.
We need to come together and take action.
The invention of my device
is motivated by a problem that I was passionate about solving.
Paraphrasing a quote by my favorite scientist,
we've come a long way, but we still have so much more to do when we look ahead.
If we all recognize
and alleviate the problems that our fellow citizens face,
we can make the world a better place.
Thank you.
(Applause) (Cheers)