A Starbucks in the Bank of China Tower has been using water from a tap in a toilet to make beverages since its opening in October 2011.

USA Today reports that images from local newspaper Apple Daily showed the tap with a sign that said “Starbucks only” a few feet away from a urinal in the dingy washroom, which the paper said was in the building’s carpark.

“Starbucks, you need to make an open declaration that such crap is not repeated anywhere else, and fire the idiot who thought up such kind of water supply ‘solution,’ ” wrote one angry customer on Starbuck’s Hong Kong Facebook page.

In its response to the poster, the store apologized. “While the water used at that store was drinking water and certified as safe, we would like to clarify any misperceptions, as quality and safety have always been our top priority,” the store’s post said. “We are now using distilled water to serve that store while we work with all parties on acceptable options.”

Starbucks spokeswoman Wendy Pang told the AFP that the water was collected less than five times a day by staff from a tap in a toilet located near the store that was dedicated for collecting drinking water.

“There is no direct water supply to that particular store, that’s why we need to obtain the drinking water from the nearest source in the building,” Pang said.

The water from the toilet tap would go through a filtration system in the store ensuring it passed local and World Health Organization standards, Pang said.

Hong Kong University School of Public Health professor Benjamin Cowling told the AFP the worry is that pathogens from the restroom will end up in the Starbucks food preparation area.

“I wouldn’t go to the restaurant in the first place if I knew they were having potentially risky hygiene practices,” Cowling said.