Watch your step — walking around the Big Crapple is tracking poop into your home.
A new study shows that NYC sidewalks may be filthier than you realize — and the Upper East Side holds not only some of the poshest homes, but also the poopiest sidewalks.
Findings published in the journal Indoor and Built Environment show a “concerning” level of turd-related pathogens, which could cause significant health issues, are carried into the home via shoes.
A team at Marymount Manhattan College took to the streets of Manhattan’s UES neighborhood where the campus is located to measure the grime left behind by dogs’ behinds.
Chemistry professor Alessandra Leri, who co-authored the study, told The Post that she and students took samples from sidewalks in the East 70s, as well as carpets and uncarpeted floors around the college’s undergraduate campus, to determine just how much fecal bacteria there is on these surfaces.
“We found numbers of bacteria that were absolutely astonishing,” Leri told The Post. “The real question was, even after the feces are ostensibly cleaned up, do the bacteria persist on the sidewalks?”
The answer was a definitive yes.
Leri, co-author Marjan Khan and the students used pipettes to collect water from puddles near campus, paying particular attention to areas that didn’t look visibly filthy — which turned out to be a lot more fecal-fueled than previously thought.
Looking for a type of fecal bacteria called enterococci — an “indicator” bacteria that’s tracked by the EPA to determine if water has fecal contamination — as well as other fecal microbes like E. coli, researchers found the exact numbers: approximately 31,000 fecal bacteria per 3.4-ounce bottle of street puddle water.
In comparison, a public beach would be shut down if there were 110 cells enterococci per 3.4 oz. per water.
“In fact, at the beginning, we maxed out our test, so we had to dilute the samples just to get a measurable number because there were so many bacteria in the puddle,” the professor said. “Enterococci are known pathogens. They cause disease themselves.”
Although 31,000 poop germs may not seem like a lot, Leri pointed out that no one is swimming in puddles — just stepping in them and tracking fecal matter into the home.
So, the other portion of the study tested the volume of fecal matter indoors, carried there by shoes. Researchers found carpeted surfaces contained more pathogens than uncarpeted, noting a “concerning level” near the entryways of buildings.
“The numbers decrease the further you get from the entryway,” Leri explained.
Of course, NYC mandates that anyone who owns or controls a dog must remove any feces left by that dog on any sidewalk, gutter, street or other public area and dispose of it in a legal manner — or risk a $250 fine. And yet, the 311 hotline regularly gets complaints about dog dumping.
“It just seems like it’s everywhere,” Upper East Side resident Clare Halpine, 35, told The Post. “It’s gross to me. It’s not great seeing piles of it. You’re always kind of dodging on the sidewalk.”
“I don’t believe Manhattan has ever been worse than it is now,” Flamur Arifi said of the amount of dog poop lately.
The 41-year-old clinical pharmacist has been living on 86th Street since 2014 and says all of his neighbors are complaining about the smelly problem.
“Now every time I go out with my daughter, it’s like a minefield because of the dog poop,” he said. “The city’s not cleaning [it up] like it used to.”
With poop’s prevalence, it’s no wonder previous studies have found items we use daily — handrails, door handles, keyboards and self-service checkouts — contain “high bacterial loads” of fecal matter.
Leri said the findings have made her rethink some habits. Since enforcing people to clean up after their dogs is notoriously hard, she said it’s best to try to modify things around the home to protect from poop.
“[It’s] most concerning for babies that crawl on carpets, toddlers that are, you know, on the floor, putting everything in their mouths and that sort of thing,” she said. “I think that you could easily decrease your exposure in the residential environment just by taking off your shoes when you get inside, leaving them inside the entryway.”
— Additional reporting by Helayne Seidman
