Air pollution has massive economic, social and environmental consequences. And there's an urgent push in many parts of the world to fight smog and clean up our cities. So it's little wonder that people are attracted to clever new ideas that can neutralize harmful particulates in the air we breathe.

I read an article that highlights the concept of a smog-eating laundry detergent that literally turns our clothes into air purifiers. In the same way that billboards have been used to scrub air, and developers have invested in smog-gobbling roof tiles, Catalytic Clothing — the developers of this new detergent concept — claim that by washing our clothes in a detergent that has incorporated tiny nanoparticles of titanium dioxide, we can trap smog particles and convert them into harmless byproducts. 

It's a pretty neat idea. And as the makers explain in the Fast Company article, our clothing covers a much vaster surface area than many of us realize: 

“If you were to unravel the fibers in clothing and set them out as a single surface, we’re all wearing the equivalent of a tennis court,” explains Helen Storey, professor at the London College of Fashion.“The other advantage is that we walk around in pollution, and that movement is an aid. It allows more air to be purified.”
But questions remain. If we're introducing new, nanosized particles into our environment and our water supply, isn't it possible that these too will have their own unintended negative consequences? Tiny microbeads of plastic were once assumed to be an innocuous addition to our detergents and soap products, yet they have now become a plague on the Great Lakes, so any new additives to detergents should be rigorously tested and carefully considered. 

Catlytic Clothing's own FAQ suggests that any nano titanium dioxide that enters the waste water treatment process will be "minimal and harmless," but given that there are already concerns and uncertainties around the impact of nano titanium dioxide in sunscreens, such claims would need to be carefully vetted before commercial application. Here's what the Encyclopedia of Earth has to say about environmental toxicity of nano titanium dioxide

Although the effects of these particles on the environment are still largely unknown, there is the possibility that photostable TiO2 could block sunlight in aquatic environments, inhibiting algae growth; or, that antimicrobial activity of TiO2 might interfere with sewage treatment processes or other aquatic environmental functions. Some studies have shown that nano-TiO2 particles can attach externally to individual algal cells leading scientists to speculate that exposures could pose a risk to species that fertilize their gametes externally.
Concerns have also been raised, says the encyclopedia, about bioaccumulation in some fish species — with potential sublethal impacts such as reproductive difficulty, pathological changes in gills and intestines, and behavioral changes. But reliable information about environmental toxicity is currently fairly limited. 

Whatever the truth turns out to be about direct environmental impacts, it seems fair to suggest that the precautionary principle should be followed with any such technologies. What worries me more, however, is human beings' ever-present search for a magic bullet. We know how to clean up pollution: we simply need to stop polluting. From EVs to solar energy to energy efficiency to planting more trees, there are plenty of tried and trusted ways to improve our environment. Getting serious about our support for these initiatives would do a whole lot more than end-of-pipe solutions to mop up the damage.

That said, there's already enough damage to go around, so there is a case for damage control and harm reduction too. From cleaning up the Great Pacific Garbage Patch to radical geoengineering concepts, there are plenty of ideas that shouldn't be rejected just because they don't solve everything. Smog-scrubbing detergents may be one of those ideas, if they can be proved to be safe. But when makers claim, as they do in the Vimeo video above, that "what we wear will change how we live," my BS-alarm starts to go off. 

How we choose to live will change how we live. What we wear will just be a part of that change.

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Laundry detergent eats smog (but is it a good idea?)
By adding tiny nanoparticles of titanium dioxide, our clothes could become air purifiers — or so they say.