Antibacterial soaps have been growing in popularity, and I can't remember the last time I went into a home with children where there wasn't a bottle of the stuff on every sink. I'm always reluctant to use it, fueled by a strange gut feeling that I'm better off learning to cope with the bacteria that surround me. Now there's some scientific back-up for my anti-antibacterial sentiments: new research found that as much as 75 percent of the chemicals used to make these products are emerging unharmed from sewage treatment plants, ending up in water supplies and subsequently used to irrigate farmland.

The research, from Johns Hopkins University and reported in the journal Environmental Science and Technology, found that 200 tons of two antibacterial compounds is ending up on agricultural land every year, mainly through the application of sludge onto fields. Two-thirds of the solid waste generated at water treatment plants around the country ends up on farmland, according to an article in the Los Angeles Times. The paper also reported that 1500 new products containing these substances - triclocarban and triclosan - have arrived on the scene since 2000.

The main problem with these compounds ending up in crops and soils is that they could kill beneficial microbes or create super-resistant bacteria or so-called superbugs. Triclosan can also react with chlorine in water to form cancer-causing compounds. There's no evidence yet of any actual harm done by the presence of these chemicals on farmland. No government agency is monitoring the presence of the substances in water or food.