Monday, February 05, 2007

Triclosan, Triclocarban Concern

Triclosan and triclocarban are small organic molecules that give antimicrobial properties to personal-care products such as soap, deodorant and toothpaste as well as durable goods such as cutting boards, baby carriers and socks. The environmental persistence of these compounds is remarkable. More than a million pounds of these chemicals flow into the nation's sewers every year. Recently improved laboratory analysis demonstrates that 50 percent of triclosan and 76 percent of triclocarban remain unchanged by aerobic and anaerobic digestion in a typical wastewater facility, where most of it is retained in the solids fraction. We can assume that the same can be said of breakdown in the septic systems that 25% of us use in the USA. Most of these solids get spread on land to fertilize pasture, forest, biomass, fiber, feed and food crops.

Triclocarban has been determined by the FDA as having no verifiable benefit. Despite a lack of evidence that these compounds accomplish anything beneficial, usage rate is very high among consumers. Among the households I have surveyed, it approaches saturation.

It makes little sense to land apply recalcitrant compounds that needlessly get rid of soil microbes. Fomenting the growth of resistant strains of disease organisms is only one concern. Soil functional capacity is largely mediated by living processes. It is the height of folly to jeopardize those functions for a useless consumer item.

US-EPA, which has oversight on land application of biosolids, is studying the situation. More work is needed, but everyone writing on this issue seems to get it: this is not an arrangement that we want to sustain.

Sources: (1), (2), (3), (4), (5), (6)

Update: The American Medical Association took an official stance against adding antimicrobials to consumer products in 2000 and has repeatedly urged the Food and Drug Administration (FDA) to better regulate these chemicals. (Source)

Photo: hand sanitizer
Originally uploaded by chewywong.

1 comment:

back40 said...

Products that use alcohol as the antimicrobial (such as Purell) are said to work better anyway. That won't help your socks, but it's a better hand treatment.