The majority of New York City mobile food vendors don’t change their gloves after exchanging money and before serving the next customer, as required by law, a new study has found.

Researchers from William Paterson University in New Jersey studied 10 food carts within 10 densely populated areas of Manhattan, a total of 100 carts. They found that 57 percent of 1,804 customer transactions observed did not involve the vendor changing gloves in between handling money and the next person’s order.

Study author Corey Basch describes the results as “eye-opening from a public health perspective” because of foodborne illness risk. “Being observant to the glove-changing behaviors of the vendors as well as overall hygiene is prudent and can reveal a great deal in a short time,” she said.

The New York City Health Code 81.13 requires that food vendors change gloves “after handling raw foods, performing tasks that do not involve food preparation or processing, handling garbage, or any other work where the gloves may have become soiled or contaminated.”