I've heard many times that it's unhealthy to store or cook food in aluminum, due to leaching, but will this apply to handling aluminum. Also, I heard that most aluminum is coated with a layer of something, to prevent oxidation; is this true?
Pure soft shiny aluminum develops a thin tenacious layer of aluminum oxide that retards further oxidation (unless worn off). The outer layer of skin is dead horny matter that resists penetration by metal atoms. However, some people do develop allergies to metals and perhaps metals dissolved in sweat (acids?) may get through to live tissue. Handling aluminum may not have been proved harmful but skeptics likely will take less chances.
The food thing is true...don't do that If your talking about Aluminum like in can, rods, screws, etc. Your ok...its an alloy. Now If you talking about Lab quality refined pure Al+3... that oxidizes fast enough that you cam see it turn from silver to white before your eyes. I've seen Pure Al stored in oil filled glasses before, but I used it in small cubes that just had to have the outer layer of oxidized stuff shaved off in oxygen free glove boxes. That stuff might dry your hands a bit. So no worries.
aluminum is very biologically unavailable- most forms of aluminium you will come in contact with wont really react with your body. And yes aluminium is actually coated in a thin layer of its own oxide (aluminium oxide) to prevent the entire thing rusting. If it was unsafe to use alot more people would know about it. You are totally fine to grill things in foil and to put foil covered things in the oven!
