Aflatoxin

[Zoe]

Hi, I've been a vegan for 13 years now and have been reading about this mycotoxin which is associated with an increased risk of liver cancer. It seems to be in many foods that I and I expect many other vegans eats (nuts, rice, pasta, beans to name a few). The more I read about it, the scarier it seems to be, I recently threw out some kidney beans when I discovered some black marks on some of them but on further inspection it seems just about every pack of beans I have will contain some beans in them with some marks (I'm in the UK where it seems quite difficult to get beans which don't come from China where there are also other contamination issues). It's quite scary to think that many of us are often eating something so dangerous. I certainly don't like the risk to the point now where it's always at the back of my mind when I eat but there doesn't seem to be any way of avoiding it.

[brimstoneSalad]

Please don't throw out food. If you don't want it, give it to somebody in need. Or put it outside for animals to eat (spread it in the grass).
Throwing out food is the worst thing, since it goes in a landfill and turns into methane.

That said, aflatoxin is in everything -- and it bioaccumulates in meat from low quality feed. You can't obsess about it, or you'll drive yourself crazy. Just avoid the foods that have the highest levels if you're really worried.
Avoid organic food (which doesn't use effective fungicides), and especially avoid peanuts.
Otherwise, you could look for food of European or North American origin... but it looks like even imported food that's high risk is tested:
https://www.food.gov.uk/business-industry/imports/importers/contaminant/Aflatoxin
You can look through the documentation.

The black spots on your beans were not an indication of toxins. Trust in your government a little more.

You can probably find test kits if you're really afraid of them:
http://vicam.com/aflatoxin-test-kits

But you're likely better served by not worrying about it so much.

[Zoe]

The black spots on your beans were not an indication of toxins. Trust in your government a little more.

I wasn't thinking the black spots were the toxins directly, just that they could be mold which could produce aflatoxin.

Of course aflatoxin is not all there is to be concerned about, there's also ochratoxin which although not at potent as aflatoxin does seem to be a lot more likely to be encountered in northern Europe. There's also the issue of heavy metals from food grown in china. I would hope that despite these risks I am generally at less risk overall from a vegan diet though.

Please don't throw out food. If you don't want it, give it to somebody in need. Or put it outside for animals to eat (spread it in the grass).
Throwing out food is the worst thing, since it goes in a landfill and turns into methane.

While I don't like the idea of throwing it out at all, I wasn't too keen on any other person or animal eating such a potent carcinogen.

[brimstoneSalad]

I wasn't thinking the black spots were the toxins directly, just that they could be mold which could produce aflatoxin.

It's possible, but it would be a trivial amount since these things are tested and have to pass certain standards.

If you want to increase the quality of your food, you can pick through them and eliminate those that are damaged or discolored.
The difference between high and low quality food is often one of sorting.

There's also the issue of heavy metals from food grown in china.

I think heavy metal levels are also tested. That's even true in China.
Levels could be a bit higher, but it's unlikely to pose any danger. Food is ruled human grade based on these standards. No reputable brand is going to import and sell contaminated food; that's a lawsuit waiting to happen, in addition to an expensive recall and loss of consumer trust.

I would hope that despite these risks I am generally at less risk overall from a vegan diet though.

Correct. Many of these things concentrate in animal products from the feed, which is lower quality than human grade food.

While I don't like the idea of throwing it out at all, I wasn't too keen on any other person or animal eating such a potent carcinogen.

Wild animals eat moldy stuff all the time. If it's too bad, they'll leave it. Their natural lifespans aren't really long enough to express significantly higher rates of cancer from first world problems like aflatoxins.

[Jebus]

I'm not familiar with this issue, but if there were something to worry about, wouldn't that be reflected in the China study? The China study research pretty much indicates the opposite.

[brimstoneSalad]

I'm not familiar with this issue, but if there were something to worry about, wouldn't that be reflected in the China study? The China study research pretty much indicates the opposite.

I don't think there's any reasonable doubt that a vegan diet is at least not worse than a meat containing diet. Epidemiologically there also seems to be a slight advantage to a vegan diet for a few kinds of cancer.

Unfortunately, many cancers are caused by viruses and UV exposure/other radiation where veganism doesn't have a strong advantage, if any.
And of course smoking, which many vegans do (including the pot).

Aflatoxin is an issue for vegans and meat-eaters, since it can concentrate in animal products from their contaminated feed too.
I can understand the desire to reduce that risk to even below what ordinary vegans would have, but I think government regulation already does a pretty good job with this.

[Zoe]

The other risk from cancer I would be concerned about as a vegan would be from polyunsaturated fats which I expect I eat a lot more of than a meat eater. If these fats oxidize then they the free radicals can damage cells. That said I expect meat eating would do people a lot more harm.

[brimstoneSalad]

The other risk from cancer I would be concerned about as a vegan would be from polyunsaturated fats which I expect I eat a lot more of than a meat eater. If these fats oxidize then they the free radicals can damage cells. That said I expect meat eating would do people a lot more harm.

Avoid cooking at high temperatures and in open air with polyunsaturated fats.

Only use them for things like baking, soups, dips, etc.

Fry with a minimum amount of monounsaturated fat like olive oil. When you're done frying, add some canola oil to the sauce to make it more fatty if you want, which will increase the amount of uncooked (or minimally cooked) PUFAs.

[Zoe]

I'm thinking more about the storage of food such as oats. Last packet I bought was absolutely disgusting out the pack so I didn't eat it. I believe rancidity is not always that easy to detect though. Over here in the UK quite a few packs seem to have small holes in them, I am told that this is done to prevent condensation but I'd have thought if air can get in then this would increase oxidation.

[brimstoneSalad]

I'm thinking more about the storage of food such as oats. Last packet I bought was absolutely disgusting out the pack so I didn't eat it. I believe rancidity is not always that easy to detect though.

Everything is rancid to some degree. you only have to worry about it in foods that are high in fat, like nuts. Oats are pretty low in fat.

Can you describe or show what you mean?
Dry staples that are not high in fat and that are in sealed containers at room temperature usually aren't going to significantly rancidify on the shelf. Heat, moisture, and oxygen exposure are the main issues.