They are microscopic components that can be used as the building blocks for faster computer processors, more powerful wireless radios, cancer-fighting medical instruments, superstrong polymers and metals, and even miniature works of art. Nanotechnology is not without controversy, however, as Billy Joy, Sun Microsystem’s co-founder, once famously warned us of the threat of “gray goo,” or self-replicating nanobots that some feared would disassemble everything on Earth. Researchers now worry about the more prosaic environmental by-products of nanotech, such as the potential health effects of nanoscale particles–carbon nanotubes, for instance, which can behave like asbestos fibers when inhaled.

Nanotechnology makes use of minuscule objects—whose width can be 10,000 times narrower than a human hair—known as nanoparticles. Upwards of 600 products on store shelves today contain them, including transparent sunscreen, lipsticks, anti-aging creams and even food products.

Health advocates worry that we’re already putting them on our bodies and ingesting them as if they’d been thoroughly tested and proven safe. Animal studies, including one with rats at the University of Rochester, have shown that some nanoparticles can cross the blood-brain barrier, which protects the brain from toxins in the bloodstream. And inhaled nanoparticles have also harmed the lungs of animal test subjects.

Europe’s regulators are far more wary about nanotechnology than their American counterparts. Britain’s Royal Society recommended in 2004 that nanoparticles be viewed as brand new substances, and the European Commission is examining them on a case-by-case basis. The U.S. Environmental Protection Agency is loosely charged with regulating nanotechnology here, but has barely dipped its toe in the water.src

Taken together, the evidence suggests considerable uncertainty about the use of nano-ingredients in consumer products. It’s just not known if they’re safe, which begs the question: Why have we gone ahead and approved them for commercial use? Indeed, we may look back at our current decade and see it, for better or worse, as a time when tiny things caused big and momentous changes in our lives.

The industry is growing in leaps and bounds, though little is yet known about what health or environmental problems the technology may bring.  They could even replace the Human RFID chip for hidden implantation secretly.