Friday, March 27, 2015

A roundup: what tobacco can tell us about glyphosate

Note: The term roundup as used in this post refers only to "a gathering of animals" and in the mathematical sense of rounding a number.

Disclaimer: The blogster has used thousands of gallons of commercial pesticides for farming commercial crops (Twitter profile Life #2 or so). Fully organic private cultivation of food and tobacco tea against infestations of rose bushes are current activity highlights.

Are you still with us?

The world's most widely sold herbicide glyphosate keeps making headlines every now and then. Lately, there was a spate of reports saying that glyphosate can cause cancer, for example as reported in Scientific American here.
But the National Pesticide Information Center pages on glyphosate don't say that, so defenders of glyphosate point there.

GlyphoFans (people who like glyphosate) rightly point to the toxicology factsheet on the National Pesticide Information Center site which tells us the substance falls into the category "Low Toxicity".

Not only is this re-assuring but GlyphoFans have failed to point out that the LD50 (the dose fatal for 50% of test subjects) of glyphosate is actually far lower than the LD50 of - take a deep breath -  standard computer printer toner, or lower than that of capsaicin (the stuff in peppers and pepper spray).

If glyphosate is not all that dangerous by itself, why the rage?

Enter tobacco again after the note in the disclaimer. We know that smoking is very dangerous, causing cancer and other nasty illnesses, yet the active ingredient nicotine is rather benign. For tobacco, the "other stuff" serves as the delivery vehicle for nicotine, as the method to get it into your body.

So, for the sake of reasoning, take glyphosate as the active ingredient and "other stuff" as the substances that make glyphosate usable.

That's called a formulation and is what you buy when you purchase pesticides at the store. There is really no practical usage scenario for many chemicals unless they are put into some sort of carrier substances.

Believe it or not, when the safety of pesticides - but also chemicals in general - is studied, the "other stuff" is ignored. The adjuvants, which is the technical term for the other stuff, are classified as inert, as not active.

Simply ignoring the oft-quoted idiom that the whole is more than its parts is easy and, to some degree, even understandable in a world as complex as ours.

You don't have to read this research paper that says Major Pesticides Are More Toxic to Human Cells Than Their Declared Active Principles but you may want to keep the basic statement in mind next time you hear that a certain individual chemical substance is harmless.

One more thing:
Yes, the long fight over the dangers of tobacco may also tell us a lot about how power and money might work in the area of pesticides, but that's a separate issue.

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