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Keven Swanzey from Maine, New York brings up an interesting point about the dicamba debate.
"Everyone seems to be talking about how crops are impacted. I even heard one say 'the biggest question is what effect does it have on crop yield,' but I have yet to hear any of these ag shows talk or even ASK the question, 'How does Dicamba drift affect human life?'"
Great question. Let's throw some facts at it. The first thing to know is dicamba is an old chemical. It was discovered in 1942 and has been used as a weed killer for decades.
This means there has been ample time to detect any longer term toxicity problems, and none have been identified. Dicamba works by interrupting the growth process of cells in plants, similar to that old stand-by, 2,4-D. This disruption process is ineffective in animals which means dicamba has very low toxicity.
Toxicity is measured by experimentation on rats usually where they are fed increasing doses, until they can determine at what level 50 percent of the rats die. This number is called LD50 where LD stands for lethal does. The higher the number the better.
I do not use the word safe when talking about hazards of any kind, because it implies an absolute that simply doesn't exist. For example, there is an LD50 for water, and we think of it as safe. What I like to do is compare the toxicity to other common chemicals. Which leads us to this chart for ingestion - eating.
Dicamba is about four times less toxic than aspirin. I included glyphosate for comparison as well. It is almost 30 times less toxic than aspirin.
As for skin absorption and inhalation, dicamba is rated very low toxicity, and keep in mind that drift vapors contain only miniscule amounts of dicamba. There have been no carcinogenic hazards detected, and it is not an endocrine disruptor.
In short, the same properties that make many plants exquisitely sensitive to dicamba make it an extremely low hazard for animals and humans.
This is the biggest reason why media are not talking about this, not suppression by government or manufacturers.
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