Michael Lorrey wrote,
>Dump it into a cage of rats. If it kills some of them, make it a toxic
>controlled substance. If it kills all of them, sell it as rat poison.
This is pretty much how the standard RD-50 test works. RD-50 stands
for "rat deaths - 50%" They figure out how high a dosage is required
to kill 50% of rats. This is the RD-50 limit. If this limit is too
close to the possible daily dosage, the substance is banned as being
too easy to overdose or have side-effects. They try to estimate how
fast the substance is excreted to figure out how many times the daily
dose can be tolerated. A fat-soluble substance that stays in the
body for 60 days must not kill 50% of the rats within 60x the daily
dose. A water-soluble substance that is excreted within 3 days must
not kill 50% of the rats within 3x the daily dose.
This gets a good average and a good estimate. It is not so good for
metabolisms that are not average. It assumes that a slow
accumulation of a certain dosage would be as bad as a single dose of
that substance, and doesn't take an increased tolerance into account.
It also doesn't allow for any type of screening to see if it can be
limited to those who will not have toxic effects. As a generic
starting point, it may be a good test.
Other problems are that humans sometimes react differently than rats.
I like to point out the examples of vitamin B7, vitamin B8, vitamin
B9, vitamin B10 and vitamin B11. Never heard of them? That's
because it turns out that they a required in rats or pigeons which
were the experimental animals, but they serve no known role in human
nutrition. All the animal experiments failed to apply to humans.
> "Max M" <maxmcorp@worldonline.dk> wrote:
> > > - No electricity. (Do you know how many people are getting
>killed by that,
> > > - No cars. They cause emission, and roadkill.
> > > - No fertilizers, they cause loss of oxygen in the oceans.
> >
> > Straw men; none of these is persistent and bioaccumulative.
This wouldn't apply, since these do not have human daily dosages.
You aren't supposed to get zapped with electricity or hit with cars.
Those deaths are accidental overdoses, not approved "safe" dosages.
The fertilizers would be tested to see if the levels of residue might
kill rats. Banning substances, such as fertilizer, for environmental
effects would be much harder to measure.
>I guess then that dihydrogen monoxide is now a banned substance.... its
>both, far more than any other substance, and is a KNOWN toxic substance.
>It tends to concentrate in cancer tumors, its the major component of
>acid rain, its the most broad based solvent, it kills more children than
>any other cause of death, and its used in several forms of torture in
>third world dictatorships. Those that release it into the environment
>ought to be tried for crimes against humanity.
I have seen this humorous position before. Literally, however, H2O
does not kill 50% of the rats until the forced dosage is many times
the typical daily dosage, while its excretion rate is much less than
one day. Also note that cancer cells used to be normal human cells,
thus, all human-required nutrients are found in cancer cells.
-- Harvey Newstrom <HarveyNewstrom.com>
This archive was generated by hypermail 2b30 : Mon May 28 2001 - 09:50:36 MDT