A washing machine isn’t actually that great at cleaning clothes. The problem, it seems, is fat. Grease and oil molecules stick to fabrics and make it hard to separate clothes from their dirty residue. To do this, detergents must add harsh chemicals such as surfactants, bleach, dyes, phosphates and other chemicals that pollute waterways and demand billions of gallons of hot water to work properly.
Yet a sprinkling of industrial diamond grit changes that. By binding with fat molecules, nanodiamonds loosen their hold on fabrics, making them easier to remove during a wash with detergent, even at lower temperatures. The particles remove twice as much fat as conventional detergents.
It’s relatively cheap as well. Diamond grit is mass produced for about five cents per carat, or about $100 per pound. Each wash only requires about 1/10 of a gram per load (although this does add up when you’re doing hundreds of washes per year).
But the greatest problem may the unknown health risks posed by nanomaterials. The only the problem is that we really have no idea about the risks of introducing nanoparticles into our lives. The National Toxicology Program sums it up (PDF) thusly:
"Should we panic? No. Is there reasonable cause for concern/caution? Yes. Is there a quick answer? No."
But the paper’s lead author, chemistry professor Andrew Marsh at the University of Warwick in England, argues in ScienceOmega: "There are all sorts of other applications for which the improved ability to remove fat from surfaces would be advantageous. These applications might be in engineering, for example, but it would also be nice to have the ability to more effectively remove fat from surfaces around the home."