14-year-old invents pesticide detector for fruits and vegetables, declared 'America's top young scientist'

Teen invents pesticide detector to prevent illness

14-year-old Sirish Subash’s invention may soon help answer the question, "How much pesticide remains on my fruits and vegetables after I wash them?" Subash, a ninth grader from Snellville, Georgia, was awarded $25,000 as “America’s Top Young Scientist” by 3M for PestiSCAND, the handheld pesticide detector he invented and plans to make available to home users after it’s fully developed.

USA Today news reporter Ahjané Forbes, reporting on Subash’s award, explained that he was the "first-place winner of the 3M and Discovery Education competition" and noted that, "[i]n his presentation, Subash used data from the Food and Drug Administration (FDA) that said 70.6% of produce items contain pesticide residues." Subash said that he wants people to be able to remove as much pesticide residue as possible because pesticides are associated with health issues such as brain cancer, leukemia and neurodegenerative diseases like Alzheimer’s and Parkinson’s.

What FDA data shows

While the article link did not provide the data Subash referenced for the 70.6% figure, according to the September 4, 2024 FDA Constituent Update for the “2022 Pesticide Residue Monitoring Report,” pesticide residues were found on 57.3% of domestic samples and 55.4% of imported samples.

Human Food Samples: 2,800 total samples (731 domestic food samples from 41 states and 2,069 imported food samples from 81 countries/economies).

     ◾ 96.2% of domestic samples and 89.5% of imported samples were compliant with federal regulations (below EPA tolerances).

     ◾ No pesticide chemical residues were detected in 42.7% of domestic samples and 44.6% of imported samples.

Table 3 of the report lists the pesticide residues found on the samples in order of frequency. The two most frequently found pesticides were Azoxystrobin and Imidacloprid, each found in 256 samples. 

In a study on mice conducted by Wen Gao et al, the fungicide Azoxystrobin was found to impair fertility by affecting egg development, which can reduce the chances of successful conception.

The neonicotinoid (pesticide) imidacloprid was identified as a major factor in colony collapse disorder affecting honeybees, according to SciTechDaily. Lee Fang, writing for the Intercept noted in his article "The Playbook for Poisoning the Earth" that the European Union permanently banned neonicotinoid-based products from being sprayed on flowers. In contrast, U.S. pesticide companies have done everything they can to continue producing and selling the pesticides, as evidenced by an internal memo from the lobby group CropLife America.

“Position the industry as an active promoter of bee health, and advance best management practices which emphasize bee safety,” noted an internal planning memo from CropLife America, the lobby group for the largest pesticide companies in America, including Bayer and Syngenta. The ultimate goal of the bee health project, the document noted, was to ensure that member companies maintained market access for neonic products and other systemic pesticides.

In 2006 the California EPA found imidacloprid to be highly toxic. Its Toxicological Profile included in the agency’s “Risk Characterization Document: Dietary and Drinking Water Exposure” (pages viii-ix) the following toxicities:

     ◾ Acute toxicity — from a single dose or multiple doses over a short period of time.

     ◾ Subchronic toxicity — "[A]dverse effects occurring after the repeated or continuous administration of a test sample for up to 90 days or not exceeding 10% of the animal's lifespan. Acute toxicity appears within hours or days of an exposure, whereas chronic toxicity can take many months or years to become a recognizable clinical disease."

     ◾ Chronic toxicity — "Adverse effects associated with chronic toxicity can be directly lethal but are more commonly sublethal, including changes in growth, reproduction, or behavior."

     ◾ Genotoxicity — "[T]he property of chemical agents that damage the genetic information within a cell causing mutations, which may lead to cancer."

     ◾ Oncogenicity — "The capacity to induce tumors."

     ◾ Reproductive Toxicity — ". . . refers to the potential risk from a given chemical, physical or biologic agent to adversely affect both male and female fertility as well as offspring development. Reproductive toxicants may adversely affect sexual function, ovarian failure, fertility as well as causing developmental toxicity in the offspring. Lowered effective fertility related to reproductive toxicity relates to both male and female effects alike and is reflected in decreased sperm counts, semen quality and ovarian failure."

     ◾ Developmental Toxicity — " . . . refers to the harmful effects on the developing organism that can occur due to exposure before conception, during prenatal development, or postnatally until sexual maturation. These effects can include structural malformations, growth retardation, functional impairment, and even death."

     ◾ Developmental Neurotoxicity — ". . . the effect of chemicals on the developing nervous system during the pre- or postnatal period principally as a result of chemical exposure to the mother during pregnancy or lactation. It may cause changes in behaviour, neurohistology, neurochemistry, neurophysiology and/or gross morphology of the CNS [central nervous system]."

PestiSCAND — 85% effective in detecting residue

Subash explained to Forbes what his device does, its effectiveness, and how it could positively affect individual health.

“My project is called PestiSCAND. What it is, is the device that allows everybody to check for pesticide residues on their produce at home,” Subash told USA TODAY. “The pesticide residues are a contaminant that's commonly found on produce items."

‍PestiSCAND's effectiveness, Subash used the AI-based handheld pesticide detector to identify pesticide residues on spinach and tomatoes. The device had an accuracy rate greater than 85% which met the project's objectives for effectiveness and speed, according to 3M.

"The residues can stay on produce after washing, and that's where they've been connected to a variety of health issues," he said. "If we could detect them, we could avoid consuming them. We could reduce the risk of those health issues.”  

How Subash's device works

Subash was also interviewed by NYSE TV’s  [New York Stock Exchange] Christine Scher after he rang the opening bell and explained how the device works (video below).

Scher:

And is this the device?

Subash:

Yes. . . . I have the actual device that I built—my prototype.

So, the way it works is you launch a mobile app that connects over Bluetooth to the device. ...

. . . 

The idea is that once the app is paired, you would point it at a produce item. Once it's directed at the item, you just tap "Scan," and then, a couple of seconds later, the results come back up on the screen.

That's as simple as it gets for testing these things.

Inspiration behind his device

Subash was inspired to create his device after his mother reminded him to wash his food before eating. Curious about the impact of washing, he researched the issue and discovered that many chemicals can linger on produce even after it has been washed.

Scher:

. . . What led you to create this idea? Do you often wash your food at home and we're noticing a lot of pesticides? What's the connection?

‍Subash:

This actually grew out of a conversation that I had with my mom. She was insisting that I wash my food before consuming it, and I wasn't really sure why it mattered or how effective it really is. So, I did some further research and discovered that pesticide residues are among many chemicals found on produce that can remain even after washing. These residues have been linked to health issues such as cancers and neurodegenerative diseases like Alzheimer's and Parkinson's. The idea is that if we could detect them, we could ensure we weren't consuming them. That’s really where this whole project started.

As for evolving the project over time, I have a couple of key ways I plan to do this. I’m mainly focused on shrinking the device down and making it more cost-effective so it can be accessible to people at home. For the future, I’m looking at a price tag of roughly $20 for a new version, but I aim to drive that down even further.

3M scientists mentored student

Students who participated in the competition received mentorship from scientists working at 3M. Subash's mentor, Aditya Banerji, helped him when he was stuck and gave him helpful pointers.

Scher:

Talk to me more about the mentorship you received from 3M in developing this particular device.

Subash:

The mentorship was great! I got to work with my mentor, Aditya Banerji, who is a researcher working with non-wovens, which is a material that 3M deals with. He was really helpful when I was stuck, guiding me forward with the project.

I encountered a couple of issues over the summer while working with the machine learning models that take the data from the sensor and turn it into the results you see on the screen. He helped me move ahead when I was stuck and pointed out ways to analyze the data coming back, which helped me figure out how to proceed with the machine learning.

A product everyone can use

Scher:

What do you think it is about your device that beat out the competition from other middle school entrants? 

Subash:

The biggest factor is that I designed this for everyone at home. I believe that this focus on making it accessible for people whose health could be improved by using it gave me an edge. The real goal for this project is to leave society a better place.

Tips for effectively washing fruits and vegetables

Subash expects it will take five years to "perfect" his device and make it available to home consumers. In the meantime, we can still wash our produce to effectively remove most pesticides and dirt from the surface. The below videos offer tips on how to do this.

Dr. Eric Berg, in the following video, advocates for the use of food-grade hydrogen peroxide. In the text below the video, is the explanation of how it works and why it is effective.

‍Hydrogen peroxide breaks down into water and oxygen. Our bodies actually make hydrogen peroxide as a defense mechanism to fight pathogens.

Hydrogen peroxide can kill microbes on vegetables. It can also help remove chemicals that kill microbes, like insecticides, fungicides, herbicides, and pesticides.

The problem with these chemicals is that they are fat-soluble and can get locked into our fat cells, organs, and neurological tissue.

Some form of insecticide, fungicide, herbicide, and pesticide has likely been used on your organic vegetables too. Even though it's not as toxic, it still might be on the vegetables you bring home. This is why a good nontoxic vegetable wash is essential.

There is hydrogen peroxide and food grade hydrogen peroxide. I recommend food grade hydrogen peroxide that's 3%. You need to dilute it by mixing 1/4 cup of food grade hydrogen peroxide in 1 gallon of water. You can then soak your vegetables in this mixture for about 20 minutes. Keep in mind that hydrogen peroxide only lasts about six months.

‍

KMOV News 4 together with Microbe Inotech Laboratories, as shown in the video below, reviewed various methods of cleaning produce and determined that vinegar and water "is most cost-effective for cleaning both bacteria and pesticides from your produce."