"Chris Lewis" wrote in message
...
Probably shouldn't be prolonging this, but what the hey...

According to JoeSpareBedroom :
"Chris Lewis" wrote in message
...
According to JoeSpareBedroom :

I know. But at this point, we're talking about yard chemicals IN
GENERAL.

Yet, yard chemicals, in general, _aren't_ neurotoxins. If you're going
to talk about yard chemicals in general, then you have to pick
something
that at least most of them have in common. Neurotoxicity isn't one of
them.

OK, fine. Let's simplify this: There are people who believe that even
though
yard chemicals cannot be tested on humans in a way that's scientifically
rigorous (as drugs are, or so we hope), it is OK to assume they are safe.
Why do they believe this?

By "safe", I don't mean anyone should drink a glass of herbicide. I'm
referring to the unintended consequences. Before we continue, do we need
to
define those consequences so we're on the same page?

No - I don't have an issue with that.

A major part of my point is that "cannot be tested ... that's
scientifically rigorous" is highly misleading. It comes out
of the confusion over whether animal testing is applicable to humans
or not. It's _well_ understood that different species have different
responses to things. But it's also understood that if you check
multiple species, and have a large enough safety margin when applying
to humans, that it will be right virtually all of the time - right
more often than would be justified in testing a material not intended
for human consumption with humans directly. It doesn't matter whether,
say, roundup is twice or even 10 times as dangerous to humans as
your test species, if the safety margin is larger, it don't matter.

[You also have to remember that with drugs, the testing isn't
just for "safe limits", it's for minimum effective dosage level.
Being off by a factor of 100 in effective dosage level simply isn't
acceptable for a drug. But it is when you're determining max dosage
level for something not intended for therapeutic value - by biasing
the acceptable levels _low_.]

Glysophate and the formulations used (such as roundup) has been very
heavily tested. On a wide range of species [there have even been a few
low dosage studies on humans]. Multi-generational. Not just by
Monsanto, but by governments and universities. It's effects on these
animals is well understood, isn't carcinogenic/teratogenic and "safe"
maximum dosage levels are well established for the tested species.
There have also been numerous on glysophate/roundup concentrations
after application in some worst-case scenarios. So you
know what the environmental dosage levels can be.

Now, if you looked at the link I've previously applied (documentation
from the Government of Canada specifying allowable limits) you'll note
that they took the lowest known demonstrable toxicity level (glysophate
is safer than common table salt in terms of acute toxicity!), and then
reduced it by a factor of ten to account for individual variation
and another 10 for species variation. Resulting in a total factor
of 100. That's the legal limit for roundup concentration.
That still being vastly higher than environmental levels
from anything short of a major spill, and that "reasonable" use by
the public is not dangerous.

I trust the scientific community enough to have lots of safety margin
and to have examined things closely enough to simply not worry about
roundup. The studies are there, and the margins are high enough to
take into account not testing directly on humans.

There are yard chemicals I'm not so confident of. And many of those
have already been restricted or banned. I don't see that happening
to roundup based on any evidence that is or likely to become available.
--
Chris Lewis,


I guess we'll just disagree on this. Until there is human testing (which I'd
like to think cannot happen), I trust none of it.