In America, dangerous drinking water is linked to a place called Flint.
From 2014 to 2019, this small city in Michigan suffered one of the nation’s worst public health crises. Thousands of its residents bathed in, gargled and drank tap water that had been contaminated with lead. It is unknown how many children will suffer irreparable harm as a result.
In addition to ripping up over 10,000 lead pipes in the area, the state of Michigan has agreed to a settlement of over $600 million, with the majority of funds going to the families of affected children.
Late last year, as part of the $1.2 trillion infrastructure bill, the federal government agreed to spend $15 billion more to replace other lead pipes across the country.
But where else is the lurking lead?
“Flint made lead in drinking water visible to a lot of Americans, but what most people don’t realize is that there are hundreds of communities in this country that have lead levels higher than Flint did at its worst,” says Khalid Alam, PhD.
Alam, a recent recruit in the fight for safe drinking water, is an unlikely warrior. But he believes his team has a way to help anyone — homeowners, civil engineers, and the government — quickly spot invisible problems in tap water.
Born in rural India and raised in Missouri, Alam trained as a scientist and recently helped launch a company, Stemloop, in Evanston, Illinois, based on his team’s research. I caught up with Alam ahead of his talk at next week’s Global Synthetic Biology Conference where he will be speaking.
Stemloop is building simple paper-based tests to detect lead, copper, and other contaminants in water samples. These tests exploit molecules first found in microbes that sense and respond to chemicals in the environment. “If biology can detect it, we can too.”
Biology as technology
Alam found an interest in biology research a few years before the Flint water crisis began. He recalls reading early findings from an emerging discipline called synthetic biology, and presenting what he’d discovered to his university peers. By the summer of 2015, he’d begun developing some of the earliest ideas behind the technology that Stemloop uses today.
Microorganisms are masters of muck. They spend their whole lives swimming through chemical soups, whether deep in the ocean or in stagnant ponds. Microbes have therefore evolved to “see” the invisible chemicals around them.
Certain chemicals, like nitrogen, must be absorbed as a nutrient. Others, like the toxic element arsenic, must always be excluded. But many chemicals are actually needed in low doses — too little and cells starve, too much and they become poisoned. Microbes, therefore, have developed many sophisticated ways of sensing the levels of chemicals around them.
“One of our goals,” says Alam, “is to catalog all the different ways that microorganisms detect the molecules around them. We want to create the world’s largest toolbox. That way, if somebody someday wants to detect a certain chemical, we can say, ‘Oh, we have a tool that does just that.’”
Stemloop builds sensors for chemicals using synthetic biology. Rather than growing whole microbes, they engineer cell-free systems that – when mixed with the target compounds – emit light. The technology can even be blotted onto paper strips for at-home testing, much like rapid antigen tests for COVID-19.
Alam and his colleague Jaeyoung Jung developed the technology while working in the laboratory of Julius Lucks at Northwestern University.
“The entire place was a pile of rubble”
After piloting bio-inspired sensors in the laboratory, the team freeze-dried some and shipped them to Chico, California. The sensors were then driven to the site of the Camp Fire in the city of Paradise, California’s deadliest and most destructive wildfire in history.
To help oversee the water testing, Alam traveled to the scorched area.
“They had done a significant amount of clean-up by the time we arrived, but there was still so much devastation. Residents were living in trailers because so many homes were just gone. Only propane canisters and cars were left — and those were all twisted and warped and bent. People were here, and these people had families.”
After a devastating wildfire — the kind that melts metal, asphalt, and anything else in its way — drinking water in the area can become contaminated with many different harmful chemicals. Runoff brings elevated levels of copper, zinc, and more.
The team showed that their sensors could detect problematic levels of copper or zinc in water samples in just 2 hours. If left to run overnight, the results were even clearer.
Detecting lead and beyond
For now, Stemloop is focused on bringing its lead detection technology to market in the United States. The company is also pursuing development deals with commercial partners who wish to detect their own undisclosed compounds. There are already ways to measure lead in drinking water, but these techniques require specialized labs with specialized equipment. This testing can be costly and slow. Still, these are today’s gold standards, and the only tests sanctioned by the Environmental Protection Agency.“We think about our tests as a way of doing rapid screening,” explains Alam. “If it’s positive, send a sample to a lab.”
Stemloop believes the market for easier water quality testing is large and will grow.
“We think there’s gonna be a cultural shift in the next decade. People are going to start to care more about water because water is a health issue. We are going to be there when that shift occurs,” explains Alam.
Thank you to Ian Haydon for additional research and reporting in this article. I’m the founder of SynBioBeta and some of the companies that I write about are sponsors of the SynBioBeta Conference and our weekly digest.