Marin officials are hoping that analysis of local wastewater will become an effective tool in addressing a surge of drug overdoses in the county, just as it was in stemming the spread of COVID-19.

In early February, the Marin public health office began testing samples collected weekly at the Central Marin Sanitation Agency in San Rafael for fentanyl, cocaine, nicotine and methamphetamine.

“We were early adopters using wastewater for COVID-19 surveillance,” said Dr. Matt Willis, the county’s public health officer. “That has proven to be one of the most effective tools for us. It’s really the same concept.”

Marin is partnering with Biobot Analytics, a company in Cambridge, Massachusetts, to conduct the pilot study. Biobot is the company that analyzes Marin’s wastewater for COVID-19 and other pathogens.

Willis said there are a handful of counties across the nation, including San Mateo, that are partnering with Biobot on similar studies.

Newsha Ghaeli, president and co-founder of Biobot, said, “There are a number of other counties in California that are very interested in expanding their COVID wastewater monitoring work into high risk substance monitoring. We are speaking with a number of other counties.”

Ghaeli declined to identify Biobot’s other partners. “We let the communities take the lead in disclosing that they’re doing this work,” she said.Ghaeli confirmed that some communities are uncomfortable about being identified as areas where illicit drugs are being consumed.

“It definitely comes up,” she said.

But Willis said shining more light on where drugs are being consumed and what type of drugs are being used is precisely what he hopes the testing will do. He says more accurate data are vital to reducing the number of overdoses in the county.

“Overdose is the third leading cause of death for anyone under the age of 75 in Marin,” Willis said. “We lose someone every five days, and we’ve seen a doubling in the number of overdoses since 2018.”

In 2022, the county recorded 659 non-fatal overdoses, up from 617 in 2021. Data on fatal overdoses in 2022 are not complete, but the projection is 62, compared to 65 in 2021.

The only data sources for overdoses come from paramedics called in to rescue overdose patients and the coroner’s office.

“With COVID-19 we had strong data systems to maintain visibility,” Willis said. “This problem by contrast is largely hidden. We’re really trying to find ways to gain better visibility to wrap our arms around this issue.”

Willis cautioned that this is still a new procedure.

“We’re not going to hang our hat on any results until we have a better understanding of how accurate it is, how well it correlates to other data sources,” he said.

But he added, “It could potentially be very powerful for us.”

He said if testing indicates an increase in the amount of fentanyl present in a community’s wastewater, alerts can be posted to warn users, Narcan supplies could be boosted there and strips used to test substances for fentanyl could be distributed.

Biobot was one of the first in the nation to measure SARS-CoV-2 in wastewater and has since brought COVID-19 wastewater monitoring to communities across all 50 states. The company was founded in 2017 to bring more real-time data to communities tackling the opioid crisis.

Ghaeli said that before Biobot began testing wastewater in Cary, North Carolina, it was assumed that the town’s surge in overdoses was being caused by increased use of heroin and fentanyl. The town was trying to address the problem by investing in a needle-exchange program.

After wastewater testing showed high levels of prescription drugs in Cary’s wastewater, the town mounted a campaign to increase public awareness about the risks associated with prescription drugs and collected unused prescription drugs for disposal. Cary reduced opioid overdoses by about 40%.

Ghaeli said wastewater sampling is also a very democratic method of collecting data related to overdoses.

“With wastewater data, everyone has an equal voice irrespective of whether you have health insurance or not,” Ghaeli said. “As long as you’re connected to a sewer system, you are represented in the data.”

Wastewater testing for drugs is being done in other areas of the United States as well, without Biobot’s help. For example, the city of Tempe, Arizona, is working with scientists from Arizona State University’s Biodesign Institute to study its wastewater.

“We began with measuring only four substances regularly in initially only three areas of the city,” said Rolf Halden, a professor and sustainability scientist at Arizona State University. “Now we have parsed the city into over a dozen different areas so we have much better geographic understanding of the community.”

Halden said wastewater testing is a good way to track the entry of new synthetic drugs into a community.

Willis said he has asked Biobot to add a new drug, xylazine, to those it is testing for in Marin. The veterinary tranquilizer with the street name “tranq” is being mixed with fentanyl, heroin and other illicit drugs.

Xylazine is already common on the East Coast, and the San Francisco’s Office of the Chief Medical Examiner recently found the drug in the bodies of four overdose victims. Xylazine can increase the risk of overdose death, make withdrawal symptoms worse and complicate the healing of wounds, sometimes making amputation necessary.

Willis said the first results for the xylazine testing should be available in about two weeks.