Researchers at New York’s Marymount College have published a study that, in its essence, attempts to establish how much dog poop footwear carries into the homes of New Yorkers on the affluent Upper East Side.
The study, released to the Indoor and Built Environment journal, concludes there’s a strong argument for leaving your outside shoes at the door – or risk tracking fecal bacteria around the house.
“Taking your shoes off is a no-brainer,” the study’s co-author Alessandra Leri, a chemistry professor at Marymount, told Gothamist.
But the study may be more interesting for the manner in which it was conducted and how it is likely to feed into neuroses about dogs and dog poop that inform countless battles between dog owners, community boards, city authorities and others – elected or merely self-appointed – who monitor the city’s ebb and flow of sanitation.
“There was a lot of crouching on the sidewalk with sterile pipettes,” Leri told the outlet. For interior surfaces, researchers used tape to collect samples and then let the bacteria gorge on fluorescent nutrients that could be examined in the lab.
The study comes as dog ownership in the city has exploded during the pandemic. With it a shortage of dog walkers has materialized as workers grudgingly return to offices. A recent New York Times article estimated that a “pet entrepreneur” – or a dog walker – catering to the wealthy can earn more than $100,000 annually.
But with more dogs comes an inevitable increase in fecal production, and city authorities have vowed to crack down on pet owners who fail to correctly bag up with a $250 fine for “failure to remove canine waste”. The law does not apply to a guide dog accompanying any blind person.
Researchers said they avoided taking scientific samples from areas obviously contaminated.
They instead identified areas of sidewalks that appeared uncontaminated, where they found approximately 31,000 fecal bacteria per travel-sized bottle of pooled rainwater on city sidewalks.
That density of intestinal microbes decreased in surface samples taken progressively further into buildings under examination and was “higher on carpets than on adjacent uncarpeted flooring”, the study said.
“Overall, our evidence indicates ubiquity of FIB [fecal indicator bacteria] on sidewalks, a translocation pathway via shoe soles and accumulation on indoor floor surfaces, particularly carpeted areas,” the study found.
