Coping with vomitoxin in wheat
I’ve been eating home-baked bread from wheat flour slightly infected with vomitoxin. I have not vomited, nor have I suffered any ill effects as far as I know. The bread tastes just as delicious as our non-vomitoxic bread. I will try to explain and can only hope that you, gentle reader, will not think that this time I really have gone mad.
Agribusiness discourages the use of the word, vomitoxin, since it sounds more horrendous than the problem it causes, at least so far. The other term for it is “DON” which stands for a word so long it is hardly pronounceable and sounds even more forbidding than vomitoxin.
This spring, parts of the country, especially in the Midwest, experienced heavy rains right when the wheat plants were flowering and beginning to set on seed. Fusarium head blight struck. This fungal disease can carry vomitoxin. Heads of wheat with the disease display whitish shrunken kernels or scabby empty husks of kernels. When the vomitoxin content gets really bad, the shrunken grains go from almost pure white to pinkish in hue and are referred to as “tombstones” in the trade. Agribusiness is discouraging the use of that word too, for obvious reasons. There were no pinkish grains in any of the fields I walked in around here. In fact the wheat all looked quite healthy to me at harvest time. Vomitoxin is not carcinogenic and hardly lethal in low amounts. Grain with low levels of it can throw livestock off feed or make humans sick to their stomach. There have been cases of gestating sows eating only vomitoxic grains aborting or getting ulcers, or so I read.
Now that I no longer raise my own wheat (old age knocketh at the door) for our bread, I like to get it straight from the field, not after it has gone through the long process of being trucked to elevators where it is comingled with other wheat, and then shipped to processors. I am almost literally surrounded by wheat fields and kind farmers, so getting wheat straight from the combine is fairly easy. But to my dismay, much of the wheat in our area was infected with vomitoxin above the allowable rate for human consumption which is generally put at no higher than 2 parts per million. (There is some confusion here because FDA’s limit for human consumption is 1 ppm, but that is on finished wheat products, not on raw grain. The lower limit applies to the milling industry which can “substantially reduce” DON during processing.)
Wheat from fields where I selected the grain for our bread tested 4.6 ppm of vomitoxin. Every sensible person I talked to said I should just throw it away. But what if all the grain in the Midwest, or even half of it, tested too high for human consumption? Throwing it away without proof that it was truly toxic would hardly be a practical solution if that meant a bread shortage. I had another idea. Most of the wheat kernels infected with vomitoxin are very light and can easily be removed from small amounts of wheat by immersing the grain in water. The light, infected grains float off. Winnowing also removes some of the light grains. We always wash and winnow our grain before grinding it into flour anyway. But, said the sensible people, some wheat berries that look healthy can still carry some vomitoxin in them. (And that is true.) Just throw it all way, Gene. Be sensible.
Gene is rarely sensible the way other people are sensible. I washed a bucket of this wheat, (all we needed since we have some left from last year), floating off the light kernels and washing off the field dust on the grain which can also carry vomitoxin. Then I spread the cleaned grain out on a sheet in the sun to dry quickly. I had the wheat tested again at the local grain elevator. This time the vomitoxin count was 1.7, safe enough to eat. Whoopee.
Actually, I was a little disappointed that the wheat had come down to safe levels. I had made up my mind to make and eat bread from it anyway just to make a statement, as they say. In fact, I had already been eating bread made from this wheat. From the homework I had done, I don’t really think I’m crazy. How many people really appreciate the paranoia that grips modern society over this business of parts per million? One part per million equals one minute in two years. In terms of wheat, it equals one teensy, weensy little wheat berry in 80 pounds of wheat which is about one and a third bushels. All the discussions of vomitoxin that I read insisted that at low ppm levels, a human would have to ingest an enormous amount of bread to suffer any ill effects.
There’s another hitch in the problem. It is almost impossible to take samples of wheat, say, from a semi truck load, that accurately represent the true vomitoxin content of the whole load when one is trying to count tiny little parts per million. Samplers are instructed to probe all parts of a load and blend the different samples thus obtained before testing. But grain handlers I talk to all say the method is fraught with inaccuracy. I’ve heard tales, which I can’t prove or disprove, of truckloads of wheat being turned down at ethanol plants because the vomitoxin content was above the limit imposed by FDA, 5ppm last I checked. (The FDA gets involved because the spent grains after distilling are fed to animals.) So the trucker drives around, gets back in line again, and, surprise, surprise, the next samplings give a test result below 5ppm. I don’t see anything wrong with this kind of subterfuge either. The second test could be more accurate than the first. We must, as a society, start using a little more common sense in how we interpret parts per million. I will bet anything that we are unknowingly eating lots of food that has in it materials toxic at high levels but not at extremely low parts per million or parts per billion. Iron in food is good for you at low levels but can kill you at high levels. I don’t mean to sound frivolous, but maybe vomitoxin has some advantages at low levels. It discourages appetite and so might be a way for the obese to loose weight.
I fear that a whole lot of wheat is going to get unnecessarily dumped, or at least a whole lot of farmers are going to get underpaid more than they should, simply because we now have the technology to measure extremely small amounts that are not necessarily significant.
Nor do I blame government officials for covering their asses by being as strict as they are. Heaven help the regulators if people got poisoned from bread, or even thought they got so poisoned.
What do you think? Leave a comment below.
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