A 14-year-old schoolboy who has invented a pesticide detector has won the prestigious title of America’s Top Young Scientist.
Sirish Subash, a ninth grader from Snellville, Georgia, has built a handheld AI-based sensor called the PestiSCAND, which has been designed to detect pesticide residues on fruit and vegetables.
The Idea Behind the PestiSCAND
Subash, who is a student at the Gwinnett School of Mathematics, Science, and Technology, spoke about his inspiration for the device.
“My parents always insist that I wash my produce before consuming it. I wondered how necessary this really is and how effective the washing is,” Subash said.
According to the Food and Drug Administration (FDA), around 60% of all produce contains pesticide residues, and rinsing produce only removes part of the contamination, resulting in a significant amount of pesticides entering our diet.
Pesticides have been linked to various health issues including Alzheimer’s, Parkinson’s, and even some cancers.
“That’s the main goal of PestiSCAND, to help people ensure that they aren’t consuming pesticides so they can avoid any associated health risks,” Subash said.
Current methods of detecting pesticides involve chopping up produce and applying chemicals to them, however this method renders them inedible.
The methods that leave the produce edible typically require a lab or they’re too expensive for the average person.
The PestiSCAND overcomes this hurdle as it can identify the presence of pesticides in a non-destructive way.
How the PestiSCAND Works
The device operates through spectrophotometry, a measurement of the intensity of light that’s absorbed by a substance by calculating the intensity of light as it passes through a solution.
Since different materials reflect and absorb different wavelengths of light based on their chemical composition, the PestiSCAND has been programmed to detect wavelengths related to pesticide residues.
Experimenting with the PestiSCAND, Subash tested over 12,000 samples of apples, strawberries, spinach, and tomatoes.
After scanning the food, PestiSCAND uses an AI-based machine learning model to analyse spectral data, identifying patterns that indicate the presence of pesticides.
The PestiSCAND isn’t intended to replace washing produce but rather acts as a helpful tool that can be used to check whether the produce has been cleaned properly.
Subash’s Mentor and Inspiration
Subash was mentored by Aditya Banerji, a Senior Research Engineer at 3M, who helped him transform his idea from concept to prototype.
For four months, Subash and Banerji worked together before heading to the competition in St. Paul, Minnesota on October 14 and 15.
Reflecting on the importance of mentorship, Subash said, “Like many other students, my fundamental passion is science, though I believe a novel idea is like a seed, such that it’ll only get so far without the proper guidance and cultivation.
“I believe the summer mentorship program gives the opportunity to continue to develop research into something that may be applied to help improve lives around the world.”
Subash has been passionate about science from a young age, but he set his sights on being named America’s Top Young Scientist after learning of Gitanjali Rao who won the challenge in 2017.
Rao invented Tethys, a portable device that quickly detects lead in water.
The PestiSCAND’s Accolades
For his invention, Subash won the 3M Young Scientist Challenge, the USA’s leading middle school science competition, in partnership with Discovery Education.
Subash was awarded a cash prize of $25,000. He hopes to attend Massachusetts Institute of Technology (MIT) and plans to invest his winnings into his college tuition.
Torie Clarke, 3M’s Executive Vice President and Chief Public Affairs Officer, said, “At 3M, we’re all about finding amazing people who bring innovation and creativity to producing products that really change lives.
“I’m beyond impressed and inspired by this year’s Young Scientist Challenge finalists who have demonstrated an incredible ability to develop creative solutions to some of the world’s most pressing challenges.”
Many of the competitors go on to create patents for their inventions, give TED Talks, found their own companies or non-profits, and are named in Forbes 30 Under 30.
Some have even exhibited at the White House Science Fair, been named TIME Magazine’s Kid of the Year, and appeared on national television on programmes such as Good Morning America and The Kelly Clarkson Show.
The PestiSCAND’s Competitors
Subash competed against nine other finalists. Minula Weerasekera, a ninth grader from Beaverton, Oregon, claimed second place.
Weerasekera developed a device for storing energy for longer through organic compounds and a sulphur-based terthiophene.
In third place was William Tan, an eighth grader from Scarsdale, New York, who invented the AI Smart Artificial Reef (AISAR).
This device encourages coral, seashells, kelp, and other marine life to grow in a safe and controlled environment. The second and third place winners both received $2,000 each.
During the competition, participants were judged based on their ingenuity, demonstration of passion and research, application of STEM principles, presentation skills, and ability to inspire others.
Subash’s Side Projects
As well as being a scientist and inventor, Subash is also the proud author of two books.
Carbon Block Puzzle, published in 2021, disentangles fact from fiction when it comes to climate change, and Biochemistry: The Fun Way, published in 2023, explains the fundamentals of biochemistry.
Subash offered some advice for STEM students and those who have a dream they hope to fulfil.
“Anything that you want to work on in life, just find something you’re really passionate about,” he said. “Because if you care about what you’re working with, you can do a lot better and it just drives you to put the effort in.”
The Future of the PestiSCAND
The prototype of the PestiSCAND had an accuracy rate greater than 85%, meeting the project’s goals for speed and effectiveness.
While the PestiSCAND did well under testing, Subash has plans to improve the device.
In particular, he aims to replace the sensor with a more accurate one and change the AI models, training them on more samples so they have a broader coverage of pesticides and produce.
Subash aims for the PestiSCAND’s price point to be $20 per device and he hopes to get it to market by the time he starts college.
He’s also planning to launch a mobile app where the PestiSCAND will clip on the back of a phone and connect wirelessly to Bluetooth, allowing users to scan the item of produce. This will make the device more portable and cost-effective.
In 15 years, Subash said he hopes to be building devices that can help make the world a better place, particularly in the field of climate change.
Amy Nakamoto, Executive Vice President of Corporate Partnerships at Discovery Education, said, “Discovery Education is incredibly proud to support student innovation over the past 17 years through the 3M Young Scientist Challenge.
“It’s more important than ever that future generations are given the tools needed to tackle real-world problems. Each remarkable participant has embodied the curiosity that will fuel these discoveries, and we congratulate them all.”
