The chemical triclosan can be found in thousands of household products - toothpaste, kids' toys and face creams, computer keyboards, yoga mats and soaps — especially soaps — because it kills germs.
Triclosan has been around for 40 years. For nearly all that time U.S. officials have been investigating the chemical's safety and effectiveness. Now the Canadian government has just declared the antibacterial agent an environmental toxin, and has proposed regulations to curtail its use in Canada.
Nichelle Harriott, with the environmental group Beyond Pesticides, is part of a group trying to get the chemical banned in the United States as well. She argues that all of the triclosan-containing products eventually wind up being washed down the drain and into the environment, where they become a different chemical, a pollutant, 240CP.
"(It) is known under the Clean Water Act as a priority pollutant, which means that EPA is supposed to regulate that chemical," she said. "We know that it is probably taken up by plants and by crops that we eat, and we don’t actually know what the effects are because no one is looking at this."
Still, even the Canadians say the evidence is inconclusive as to whether the chemical causes harm to people. Harriott disagrees.
"A lot of work that we have done have shown that there are some serious human health effects that we need to take a look at," she said.
Harriott said that she and her group are concerned that triclosan may impact people's hormone levels — especially if it's being consumed up the food chain by plants and animals. That would mean humans are being exposed not only in the products they use, but in food they eat.
But even Harriott's group, while concerned, doesn't have concrete evidence of those specific problems. Others are concerned the chemical may lead to increase antibiotic resistance — a persistent problem in medicine today.
"Once resistant to triclosan, they may have cross-resistance to other antibiotics, then there is a serious public health concern," Harriott said.
And there's one other concern — though it's as unconfirmed as it is scary. There have been some indications that when triclosan is mixed with chlorine — a chemical often found in small amounts in water — it can form chloroform. Chloroform is a sweet-smelling chemical that's used to make Teflon and as a solvent, as well as an anesthetic that can be used to render someone unconscious.
"That waves a lot of red flags. If you’re brushing your teeth, and a lot of toothpaste contains triclosan, are you being exposed to chloroform through the chlorine in the tap water?" Harriott asked. "Our regulatory system tends to be more reactionary than precautionary, and so we do allow chemicals into the environment without sufficient human and environmental health overview. So we’re now retroactively trying to do something about this."
The Environmental Protection Agency would be responsible for regulating triclosan as an environmental pollutant, but the Food and Drug Administration spokeswoman Shelly Burgess said there's no reason to believe, presently, that triclosan is hazardous to humans, but the agency is engaged in an ongoing review to evaluate its safety.
"What consumers should know is that we don't have sufficient safety evidence to recommend changing consumer use of products that contain triclosan at this time," she said.
While Burgess couldn't say whether the use of triclosan in products like hand soaps provide a benefit to consumers, she also said there's no limit to the concentration of triclosan in consumer products, such as consumer antibacterial soaps.
"This is because FDA’s view of the safety and effectiveness of triclosan is ongoing," she said.
The FDA review is supposed to be completed by winter 2012.