Triclosan, a common disinfectant present in household products such as body washes may make bacteria resistant to antibiotics, a study published today suggests.

Scientists from the University of Birmingham in the UK and colleagues have discovered a link between a major mechanism of antibiotic resistance and resistance to triclosan.

They found that bacteria which mutated to become resistant to quinolone antibiotics also became more resistant to triclosan.

The researchers showed that the quinolone-resistance mutation altered the way the bacteria package their DNA inside a cell and that these mutants had also turned on various self-defence mechanisms - together these gave triclosan resistance.

Quinolone antibiotics are an important and powerful group of human medicines, and this new discovery raises concerns that the use of triclosan can give antimicrobial resistance.

"We think that bacteria are tricked into thinking they are always under attack and are then primed to deal with other threats including triclosan," said Mark Webber, Honorary Senior Lecturer at the University of Birmingham.

"The worry is that this might happen in reverse and triclosan exposure might encourage growth of antibiotic resistant strains," said Webber, corresponding author of the study published in the Journal of Antimicrobial Chemotherapy.

"We found this can happen in E coli. As we run out of effective drugs, understanding how antibiotic resistance can happen and under what conditions is crucial to stopping selection of more resistant bacteria," he said.

Triclosan has been the cause for some concern which has led to a ban across the EU and US in its use in hygiene products (hand, skin and body washes), researchers said.

Many other antimicrobial agents are, however, still used in these products, they said.