nanotech seems to be the buzzword of nowadays item , nano food , nano tech both used in food, electronics, cosmetics

especially food, can it be one day the food ingredient sip into another parts of organ where it not suppose to go since its NANOly measured and supposingly can pass through certain wall of certain density?

Anyone with a medical education could easily spot at least two obvious problems that could come from conventional nanotechnology.

1) Theoretically, loose carbon nanotubes, if inhaled, could be as problematic as inhaled asbestos crystals. Preliminary studies are supporting this idea.

2) Nanopollution - accidentally created clouds of airborne or water-borne microparticles - could be even more deadly than conventional air or water pollution. Microparticles in city air are believed to be the primary cause for recent increases in incidence of heart disease and asthma. This is because tiny particles in the air can pass through the lungs and enter the bloodstream, triggering immune responses such as inflammation in both the lungs and cardiovascular system.

You don't need to have smart, self-replicating nanomachines in order to have a health care problem. Just dumb bits of micro stuff could be enough to do you in.

We're not in any endanger of being turned into the consistency of custard by self-replicating nano-machines designed to digest organic matter. Because by the time we have that level of technology we would be able to build a counter-attack nano-bots to eat its own kind.
So if it turns out that nanotech is dangerous, there is an important question. If you think about how ineffectively we deal with polution clean up currently, even considering the advantages of using chemistry (heavy metals in soil, water, oil spills etc). How the hell do you clean up polution from nanotechnology?

...that we are in danger of being converted into Borg drones by out of control nanoprobes?