The truth about reusing plastic water bottles

Dr Paul Matewele appeared on BBC One to discuss the bacteria found in reused plastic water bottles.

Date: 14 February 2017

Dr Paul Matewele, Senior Lecturer in the School of Human Sciences and expert in Microbiology and Immunology, worked with BBC One’s Food: Truth or Scare to examine the bacteria found in reused plastic water bottles.

There have been a number of media reports over the past few years that suggest reusing plastic water bottles can be detrimental to health, with many articles focusing on the high levels of bacteria found in the bottles.

To help determine the truth behind these claims, and whether we should be using a fresh bottle every time, Dr Matewele teamed up with the BBC to test the water bottles of Paralympian Steve Brown and his wheelchair rugby team.

Taking swabs from each of the team’s water bottles, Dr Matewele analysed the levels of bacteria found on the rims and insides.

Dr Matewele said: “I was expecting to find some microorganisms from the gut. It is quite a good thing for the body to be exposed to bacteria as it builds up your immune system. But there is a critical number and if it goes beyond that your immune system can’t cope.”

All the bottles tested contained bacteria, with the most reused also showing signs of mould. The tests also found lower levels of more serious pathogenic bacteria which if left to fester could lead to more serious issues.

To ensure bottles are safe to use Dr Matewele advises cleaning and replacing them regularly.

Dr Matewele often appears in the media to provide expert comment on microbiology and recently conducted testing for the Mirror investigating the bacteria found on everyday household items.

BBC Food: Truth or Scare is available to watch on the BBC iPlayer until 11 March 2017.