Scientists can track the spread of opioids in sewers. But do cities want to know what lies below?

The French novelist Victor Hugo described the sewage system as “the consciousness of the city,” a place where there are no secrets. Transporting millions of gallons of wastewater, the sewer contains a record of the public’s health and the substances it consumes.

Today, science has made possible what Hugo could not have fathomed in his day: water-sampling robots placed at strategic points in a sewer system and capable of delivering ever-more precise information about a community’s health.

As the country confronts an opioid crisis that kills more than 60,000 American each year, one Cambridge, Mass.-based company is hoping that it can use that kind of technology to measure traces of the drugs in sewers. Doing so, according to the firm, Biobot Analytics, could help to reveal remarkably detailed patterns of drug use — and give communities a powerful tool to detect emerging public health threats.

“Our goal,” said Newsha Ghaeli, one of the company’s co-founders, “is to transform sewers into public health observatories.”

The question is whether communities are ready to reveal their own secrets. Researchers, using wastewater-based epidemiology, would effectively be treating sewage as a collective urine and stool sample, made available willingly or not by everyone who uses a toilet. And by looking for the specific molecules that are found when opioids pass through the human body, it would be possible to distinguish between drugs that are flushed down a toilet and those that were ingested.  

“It really comes down to finding a city that wants to know about what’s in their sewer,” said Daniel Burgard, professor and chair of the chemistry department at the University of Puget Sound.

With the stigma attached to drug addiction, some cities may be reluctant to know more of the extent of local opioid use, Burgard said. Government officials and residents may see wastewater-based epidemiology less as a public health tool and more as an insidious threat to their own reputations.

Biobot Analytics will also need to find customers willing to pay hundreds of thousands of dollars to use their technology. So far, Ghaeli and her co-founder, Mariana Matus, both former researchers at the Massachusetts Institute of Technology, have tested their approach to wastewater-based epidemiology in Boston, Kuwait, and Seoul, using their robots to detect bacteria. They have also assembled a team of biologists, architects, chemists, and engineers.

Many European cities have already embraced wastewater-based epidemiology techniques to detect illegal substances in their sewer systems. But such testing is conducted at wastewater treatment facilities. That, experts say, just isn’t the same as the kind of intelligence that could be gathered with Biobot’s technology.

Analyzing wastewater before it converges and mixes downstream at treatment facilities permits Biobot to measure drug use of not only an entire city but also of specific locations, down to areas of a few thousand people. The more precise method could enable city officials to first pinpoint communities that need interventions, like substance abuse programs, and to later measure the success of those programs in lowering drug use.

“Going down into the sewer system below the city is the most valuable approach compared to just looking into the influx of a big wastewater treatment plant,” said Carsten Prasse, assistant professor in the department of environmental health and engineering at Johns Hopkins University.

A pilot site

Biobot’s technology will get a test run in Cary, N.C. Located near North Carolina’s Research Triangle, the town of 160,000 may seem like an unlikely proving ground. It has one of the highest median household incomes in North Carolina and one of the lowest crime rates in the country. It recently hosted a festival where participants sculpted mice out of pimento cheese; town officials plan to celebrate International Yoga Day with free classes.

But like other communities, Cary has learned that it’s not immune from the opioid epidemic.

It started on the Monday after Thanksgiving in 2016, when the fire department responded to five opioid-related overdoses, three of which were fatal, recalled Mike Bajorek, the deputy town manager. Less than two months later, after consulting with town officials, the mayor declared that Cary had an opioid problem and that fighting it would be one of his top priorities. In 2017 Cary saw 46 overdoses, a 70 percent increase over the previous year.

While searching for ways to deal with the crisis, Bajorek and other town officials learned about wastewater-epidemiology and contacted Biobot Analytics.

Together, they designed a three-month pilot program that is expected to run through this summer. The project will be funded by a $100,000 grant from Bloomberg Philanthropies as part of a nationwide competition that encourages town leaders to address challenging problems with innovative ideas.

“We want to use the results of this study as a diving board into a community conversation,” said Bajorek. “We want to say, ‘Hey, this [drug use] is happening not in dilapidated homes or buildings or under bridges here in Cary. This is happening in bedrooms throughout our communities and we need to talk about it.’”

Biobot and Cary will install robots in 10 locations throughout the town. Over a 24-hour period, each robot will pump 2 1/2 gallons of water through a filter, trapping any dissolved chemicals.

Biobot scientists, with the help of a machine that identifies molecules based on their mass, will then analyze the filter to estimate consumption of legal and illegal opioids including morphine, hydromophone, oxycodone, heroin, and fentanyl. The sampling and subsequent analysis will be performed once every two weeks to follow drug use over time.

Because each of the sample areas includes data from 4,000 to 16,000 residents, scientists will not be able to track individual drug use.

Although Biobot has not yet begun collecting data — town officials are currently installing the robots — the project is already prompting discussion among residents.

Many are excited about the potential of the technology as a solution to issues in the town. But most people don’t quite understand the magnitude of the opioid problem, said Rebecca Savitski, a real estate broker in Cary.

In that sense, the town’s study might help further expand awareness.

Among her friends on Facebook, Savitski has observed changes in how people think about opioid abuse. “There was compassion,” she said, “that this is a disease that anybody could be affected by. It could be our neighbors, it could be our children, even our senior citizens.”

The future of wastewater-based epidemiology

Biobot is hoping that success in Cary will help convince other cities to adopt their technology. The company recently pitched its service to more than 800 mayors at the United States Conference of Mayors, an annual meeting that promotes effective urban and suburban policies.

Matus said the company has generated “a few more leads from that event” and that the its goal is to have five more cities signed up over the next year. But there are challenges, beyond the concerns any cities might have about airing details of local opioid use.

This kind of wastewater-based epidemiology is still relatively new, and that means selling the service is also an education campaign.

“Cities and mayors are really busy and not everyone has time to go through this involved process,” said Matus.

Europe has seen success in testing based on wastewater treatment facilities. The European Monitoring Center for Drugs and Drug Addiction, an agency of the European Union, collates the data collected at those facilities and prepares a report for the public. In 2018, it described drug use in 56 cities located across 19 countries.

Experts believe that multiple factors contribute to Europe’s early acceptance of wastewater-based epidemiology. European governments play a more active role in health care issues, making city officials and citizens receptive to the practice. Europeans may be more open to discussing drug use, which tends to be a taboo subject in the United States. And Europe has developed a critical mass of scientists and government officials sharing data, which reduces the stigma associated with drug use.

Wastewater-based epidemiologists in the United States are hopeful that a similar critical mass or small group of American cities will form in the next few years.

Burgard, the researcher at the University of Puget Sound, noted that the urgency of the opioid crisis may inspire U.S. cities to try new approaches.

“I think cities may be looking past the stigma,” he said. “They already know they have an opioid crisis, so [they’re] trying to find any tool possible to help them deal with that.”