Small shampoo bottles in hotels carry risks that few travelers are aware of.

of refillable dispensers have shown that bacteria can grow and form biofilms inside these systems. Previous studies cited by the researchers found contaminants in approximately one in four dispensers tested.

occurs when new product is added without first emptying, washing, disinfecting, and drying the container.Bacteria present in product residues may adhere to the inner walls and contaminate the newly poured contents.

There’s also a risk of tampering with the dispenser by guests if it’s easy to open. Stories circulate online about people allegedly pouring depilatory cream or other substances into these containers.

While there is no evidence that this is