UMass Amherst Researchers Find Triclosan and Other Chemicals Accumulate in Toothbrushes

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A team of environmental chemists at the University of Massachusetts Amherst led by Baoshan Xing, who has long studied how polymers take up chemicals they contact, report in the current issue of Environmental Science & Technology that triclosan, an antibacterial agent in some over-the-counter toothpastes, accumulates in toothbrush bristles and is easily released in the mouth if the user switches toothpaste types.

A team of environmental chemists at the University of Massachusetts Amherst led by Baoshan Xing, who has long studied how polymers take up chemicals they contact, report in the current issue of Environmental Science & Technology that triclosan, an antibacterial agent in some over-the-counter toothpastes, accumulates in toothbrush bristles and is easily released in the mouth if the user switches toothpaste types.

Xing, a professor in UMass Amherst’s Stockbridge School of Agriculture, with postdoctoral researcher Jie Han, research associate Wei Qiu and others, points out that triclosan is not found as an active ingredient in all toothpastes but only in those marketed as antibacterial.

They found that brushing with these products allows triclosan to accumulate in nylon bristles and other soft toothbrush parts, where it stays unless the user switches to a non-triclosan toothpaste. In that case, the triclosan held in the bristles readily comes out with each brushing, exposing the user to triclosan at unregulated doses, Xing says, depending on the chemical composition of the new toothpaste.

In September 2016, the U.S. Food and Drug Administration (FDA) banned triclosan from use in over-the-counter antibacterial liquid and bar soaps, gels and wipes, but it is allowed in toothpastes. On its triclosan consumer information page, the FDA says there is evidence that triclosan found in one brand was “effective in preventing gingivitis,” or gum disease.

Continue reading at University of Massachusetts at Amherst