I went to stir the cabbage roll soup and found the metal lid to the diced tomatoes in the soup. It's been in there for at least an hour with all the food in the crockpot cooking on high. I got it out and still have the food cooking. I'm not sure if we can eat this now or not?

  • So that is how they get the high iron content into the spinach... :) – simbabque Oct 7 '15 at 11:20
  • I'm very glad that the chef found the offender in the soup, and not a guest! – dotancohen Oct 9 '15 at 8:24

When you can foods, even in a mass production setting, you're pouring near boiling contents into the cans. So heating it in your soup is no different than having used those tomatoes in the soup. If it wasn't food safe it wouldn't be used for canning. It would do no more harm to eat the soup than it would be to eat the tomatoes out of that can.


While there may have been health risk in the past with the coating on many canned products, its incredibly rare in modern day. While trace amount of tin are generally safe, in a larger quantity they can cause nausea and vomiting, but generally no long term effects as these are mostly related to the inability to digest tin. In the UK some canned products are coated in a Bisphenol-A compound which is a known carcinogen. Though this is becoming less common, as BPA is generally avoided in food containment. Though the toxicity of BPA is still widely debated, its generally best to avoid it.

Most cans are made of steel, which if dissolved, even in relatively large quantities is not a health risk. For instance, many pans are made of steel or iron. Most commonly these cans are coated with aluminum as its much cheaper to plate steel with aluminum rather than tin. Aluminum can be toxic in large quantities, but aluminum is very resistant to corrosion, as it tends to form an oxidized coating which prevent most corrosion.

There are some minor safety hazard in consuming the coating on certain canned products, though its increasingly less common to find products canned in these containers that contain potentially hazardous materials. Tin coated cans have made people nauseous in the past, due to the tin dissolving from acidic contents like fruit. Though generally the can has to be rather old, and discoloration is a good indicator in this case to avoid consuming problematic amounts of tin.

I'd say being that there are no reports of people becoming ill from cooking a portion of a can, that its safe to assume that there are no major health implications. Though if you are worried, you may want to contact the company that packages the specific brand of canned goods you are using.


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    @Raphael: aside from anything else, if the can was dirty then the dirt's in the soup now. I still wouldn't worry about it too much, just as long as you don't store your cans with your asbestos or anything. – Steve Jessop Oct 7 '15 at 8:11
  • Cans are coated with zein, so it's not really bare metal. – Escoce Oct 7 '15 at 19:50
  • @Raphael See my addition about the chemical makeup of cans and possible health implications related to that. – tsturzl Oct 9 '15 at 3:51

It's nothing. Since you've already fished it out, you're done having to deal with it, just keep going. No harm will come to you or your dish.

  • Okay thank you for your comment. Wanted a second opinion to make sure dish was still good. – MamaOf2 Oct 7 '15 at 1:36

Though the other answers correctly state that the lid is harmless, what was dropped into the soup was the lid and additionally everything else on that lid. I had once briefly worked at a warehouse that handled, among other things, some food products. There I learned that the outside of the can is no less important than the inside. I have seen rat poison distributed on a pallet of canned soda, which was later distributed to stores to be put in vending machines.

If the lid was properly cleaned, then there is probably no worry. But if the lid was exposed to chemicals, poisons, or dirt then it would have to be properly cleaned to be safe. I like the "lick test": If you would comfortably lick that lid, then the food is probably safe. If you wouldn't lick the lid, then don't serve the food.

  • If anything that critical is on the outside of the can, wouldn't the fact that the can has been handled alongside the food be a risk as well? Or, for that matter, that fact that "pouring stuff out of the can" most likely was a path of contamination, too? Or... am I just way too messy in my kitchen? – Layna Oct 7 '15 at 13:24
  • @Layna: That is probably a question for a toxicologist or a biologist. You may be correct. I'll tell you, I always wash cans, jars, and other packaging before opening them now. – dotancohen Oct 7 '15 at 13:57
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    I usually at least stiffly wipe it clean with a paper towel. – Escoce Oct 7 '15 at 19:52
  • Given I don't recommend consuming rat poison, it has a relatively low toxicity to humans, and there are no reported cases of fatalities from rat poison in humans(that I was able to find). Though I agree, its easy enough to just rinse or wash the lid. – tsturzl Oct 9 '15 at 3:56
