A recent study from US-based waterfilterguru.com found reusable bottles can harbor 40,000 times more bacteria than the average toilet seat – describing them as being like a “portable Petri dish,” reported the New York Post. Bottles contain twice as germs as the kitchen sink; can carry four times the amount of bacteria as a computer mouse; and 14 times more than a pet’s drinking bowl!
On average, the bottles harboured as much as 20.8 million CFUs of gram negative bacteria. The spout and screw-top lid bottle were the most infected with 30 million CFUs. For comparison, a toilet seat has 515 CFUs. Meaning the bottles carried bacteria four times that of a computer mouse, 14 times of a pet bowl, and yes, 40,000 times more than a toilet seat. "The human mouth is home to a large number and range of different bacteria. So it's not surprising that drinking vessels are covered in microbes," said one of the scientists. The scientists stated that to avoid drinking contaminated water, the bottles should be washed at least once a day with soapy water. Moreover, the bottles should be sanitised at least once a week.