Rubber ducks can be full of nasty bugs at bath time

By Dr. Ananya Mandal, MDMar 28 2018

Researchers have found that the cute little rubber ducks that float around in bath tubs and come in contact with potable water are homes to millions of bacteria and harmful microbes. They found that these toys contain water that’s seeped into them and when squeezed, they release this dirty water into the bath water. The water is rich in microbes that could be potentially “pathogenic” or disease causing especially among children, they write.

Image Credit: Hayati Kayhan / Shutterstock

Swiss and American researchers from Swiss Federal Institute of Aquatic Science and Technology, ETH Zurich and the University of Illinois looked at five such rubber toys and found that four of them contained bacteria including legionella that can cause serious lung disease called legionnaire's disease. The fluid inside the toys also contained a bacteria called Pseudomonas aeruginosa that is usually responsible for hospital-acquired infections. They looked at a total of 19 different bath toys obtained from real life situations. The study, aptly titled, “Ugly ducklings—the dark side of plastic materials in contact with potable water”, was published in the latest issue of the journal Biofilms and Microbiomes.

This is one of the first studies of this kind that studies the toys and their potential to cause disease and infections, say the researchers. They noted that the concentration of the bacteria and fungi within these ducks was very high at up to 75 million cells per square centimetre. According to researchers the bacteria do not come from the tap water alone. They arise from the polymers within the plastic material that provide the nutrients that these microbes need to grow and multiply. The microbes in addition also thrive on the bodily fluids that accumulate in the bath water like urine and sweat. Nitrogen and phosphorus in the water and contaminants from soaps and chemicals also make it a comfortable atmosphere for the bacteria to grow. Microbiologist and lead study author Lisa Neu explains that their study looked at 19 different bath toys including rubber crocodiles as well as the ducks. She says that they found that it was the chemical carbon structure that the toys were made of that provided growth material for the bacteria.

According to researchers, some amount of bacteria exposure is good for the kids to boost their immunity. However the bacteria that they found on the rubber ducks is far from safe for the kids. It could cause ear, eye and gut infections in the kids which could be serious. Kids usually squirt bath water on their and each other’s faces and that could be dangerous they explain.

To prevent this, both toys need to be made up of better quality polymers that could prevent bacterial and fungal growth on them.

This study was funded by the Swiss government to look at different household objects that could be harbouring harmful bacteria. As of now the government has not made any recommendations regarding use of better quality polymers for making these toys.