Researchers in the US have announced the discovery of an improved "biocidal" treatment for cotton, which quickly kills the bugs that cause nasty niffs.

Dr Gang Sun of the University of California bonded compounds called N-halomines to cotton textiles, in a process similar to that for producing "permanent press" clothes.

Death to germs

N-halamines contain chlorine atoms, which spell death for a wide range of bacteria and viruses. The way the chlorine is held in the molecules - by covalent bonding - means they can be released to attack the bugs.

Although the chlorine is used up in killing the germs, it is easily "recharged" by using a dilute solution of bleach once every five washes or so.

The technology is being developed by Seattle-based company HaloSource, which aims to have products on the market within six months. Sportswear, hospital and hotel bedding, household sponges and handkerchiefs could be among the first applications, according to HaloSource president Dr Jeffrey Williams.

Million times reduction

To test the effectiveness of N-halamines, workers wore socks and t-shirts treated with the chemicals. They showed noticeably reduced odour and importantly no adverse skin reactions, Dr Williams said.

N-halamines can also be incorporated into cellulose fibres, so the compounds could be used in wooden chopping boards to kill food-borne bacteria.

"We can show a million times reduction in salmonella in two minutes," said Dr Williams. Most other germ killing treatments "take anywhere from 20 to 30 minutes to bring about much more modest reductions."