John Cahill asked about the stability of Roundup.
His wife had heard a claim by a Monsanto rep that
the material broke down in a few hours when exposed
to sun.
The Monsanto rep wasn't totally wrong about Roundup
breaking down very fast when exposed to light. It
also breaks down fast in a lab. The material was
promoted by Monsanto as fast-breaking and therefore
not an environmental problem.
The fact, however, is that glyphosphate is adsorbed
onto soil particles and clings on over an extended
period. It does persist in the soil and gets into the
water table. It is not a particularly toxic material
but it is used in such huge quantities that it is an
environmental problem.
I've worked with this material for a number of years.
It's effective but it's not environmentally friendly.
The thing that disturbed me more than the material was
the way the stuff was promoted. . . . the statement that
it breaks down in a matter of hours and therefore was
not an environmental problem is rediculous.
Malathion, for example, has about the same vapor pressure
as acetone. The stuff evaporates very fast . . . spray the
material on a plant and by the time you can get a sprayed
leaf into a lab, the malathion is pretty much gone. It's
not unlike a poison gas . . . what has time to do with it?