Study finds rising levels of triclosan-derived dioxins in Mississippi River
Triclosan is an antibacterial agent found in many hand soaps, deodorants and other consumer products. Lobby groups have claimed that scientific studies link the chemical to endocrine system disruption, cancer and increased dermal sensitisation.
Studies have also shown triclosan to be of environmental concern. About 96 percent of the agent is disposed of in residential drains, leading to the chemical entering wastewater treatment plants, it has been claimed.
Environmental concerns
According to the Environmental Protection Agency, in aquatic environments, “triclosan is expected to attach to the surface of suspended solids and sediments and may bioaccumulate, potentially posing a concern for aquatic organisms.”
The latest University of Minnesota study examined sediment core samples from Lake Pepin, an enlargement of the Mississippi River, analyzing them for triclosan, the four dioxins derived from triclosan and the entire family of dioxin chemicals.
Researchers found that over the last 30 years, the levels of the four triclosan-derived dioxins have increased between 200 and 300 percent in Mississippi River sediments. In contrast, researchers found that levels of other dioxins have decreased by between 73 and 90 percent.
“These four dioxins only come from triclosan. They didn’t exist in Lake Pepin before triclosan was introduced, said William Arnold, civil engineering professor at the university. “In the most current sediments, these triclosan-derived dioxins account for about 30 percent of the dioxin mass,” he added.
Arnold said that the toxicity of the dioxins in question is not currently well understood, nor is the extent of its distribution in the environment.
Triclosan controversy
The US Food and Drug Administration (FDA), has been running an ongoing scientific review of the use of triclosan, the findings of which are set to be published in spring 2011.
In September 2008, the international NGO ChemSec listed the ingredient among 266 other chemical ingredients it felt were of ‘high concern’, urging companies to find alternatives in the cosmetics industry.
Recently, Washington D.C. Representative Edward Markey issued a statement calling for a ban on its use, stating that there are “many troubling questions about tricoslan’s effectiveness and potentially harmful effects.”
