This is inspired from an article that first appeared on the blog Innovation News entitled;
The first is band aids that use silver nanoparticles in the adhesive which kill bacteria. So we looked up silver nanoparticles to see if they were candidates for toxicity. We discovered that science daily published an article titled; Are Silver Nanoparticles Harmful? According to a study by the Norwegian Institute of Public Health, silver nanoparticles cause damage to testicular cells in rats and mice. Further statistics and studies needed.CONCLUSION: Nano-hydroxyapatite has no accumulative toxicity to rabbits, it is suggested that it is safe when the hydroxyapatite-sol was applied intravenously as a drug carrier in small dosage more less than the medium lethal dose, even as a kind of anticancer drug.
The next one that jumped out were the phytosterol nanoparticles in the canola oil to reduce cholesterol. Toxicity is possible a study suggests. Lab rats once agian were called upon to test the effects of phytosterols, (not in nano particle form) and found it poisoned their little heart cells. Ouch! That’s right. The levels of toxicity were at the level to raise concerns for humans. 
Quantum POP asks; is it better to eliminate cholesterol by adding ingredients that do not exist in it naturally or simply choose other foods? Also; Can nanoparticles of phytosterols be introduced in such low levels that they are not toxic? Research is also showing that many rimes other nanoparticles can be introduced which eliminates the toxicity of the beneficial to the particular physical condition to be modified. For a scholarly study on nanoparticles and cholesterol please read. http://www.kipbiotech.com/wp-content/uploads/2010/02/micellar-phytosterols-effectively-reduce-cholesterol-absorption-at-low-doses.pdf
The last item in the article entitled 10 Ways You’re Using Nanotech Right Now (And Don’t Even Know It) that actually named the nanoparticle in question was condoms that used our old friend silver nanoparticles for bacteria and STD infection fighters. However there is the question of testicular cancer being linked to the silver. Condoms with silver nanoparticles may need to be avoided till further studies are done.
Their are other products and advancments listed in this article beut these are the only items in the article where the specific nanoparticles are named.
According to the web site Scribd http://www.scribd.com/doc/61507151/Introduction-and-Application-of-Nanotechnology-in-Food-Technology-2 there were 200 companies worth over 25 billion dollars.
With the Olympics starting this week Quantum POP wonders if there are numerous performance enhancing nanoparticles, that will not be detectable by Olympic officials being ingested by our modern athletes. According to an article in 
Researchers are already experimenting with blood supplements based on oxygen-carrying nanoparticles for use in emergency situations. If an athlete get more oxygen in their system their performance could definitely be enhanced.
There was a lot of talk about the possibility of biologically infused nanodevices that could perpetually maintain certain thresholds of performance. Nanotechnology is used already in the Olympics widely, to alter the properties of sports equipment and, with it, improve athletic performance. Carbon nanotubes, for example, are used to make bicycle frames and tennis rackets lighter and more durable and give golf clubs and hockey sticks a more powerful and accurate drive, while a coating of nanomaterials makes kayaks faster and more stable and keeps tennis balls bouncy for longer.
No question that nano particles are increasingly entering the bloodstream of many people in the developed world. Many times without adequate testing. Even nano particles that are used for textures can when handled enter the bloodstream where in their larger form they would not.
In the short term proper labeling of nano as well as normal substances seems to be warranted.