Toxic level for Roundup? (Was:Re: GMO contamination evidence)

Brian Sandle bsandle at southern.co.nz
Mon Dec 27 00:42:21 EST 1999


In sci.bio.food-science troyc at geneseo.net wrote:
: In article <946229058.926321 at mnementh.southern.co.nz>,
:   Brian Sandle <bsandle at southern.co.nz> wrote:

:> of a number of options and when Monsanto has applied in several
:> countries
:> for a
:>
:> relaxation in environmental legislation to allow a 200 fold increase
:> in
:> glyphosate residues
:> in soya.

: In what countries?  From what level to what level?  I am aware that
: Monsanto applied for a change in registration since the use of the
: herbicide has changed (required by law).  Have you any real evidence or
: figures other than the rantings of the activist who's page this is taken
: from?

The allowable residual level of glyphosate for soybeans was raised 
from 0.1 mg/kg to 20 mg/kg to make possible importation of the 
beans on which it had been used.
 
from:   Linkname: Lords Hansard text for 21 Jul 1999 (990721-01)
        URL:
          http://www.parliament.the-stationery-office.co.uk/pa/ld199697/l
          dhansrd/pdvn/lds99/text/90721-01.htm
 
In the following the LC50 is the concentration which will kill 50%
 
 
     * Effects on birds: Glyphosate is slightly toxic to wild birds. The
       dietary LC50 in both mallards and bobwhite quail is greater than
       4500 ppm [1].
from:   Linkname: EXTOXNET PIP - GLYPHOSATE
        URL: http://ace.orst.edu/info/extoxnet/pips/glyphosa.htm
 
Now 4,500 ppm is 4,500 mg/kg. That is only 200 times the allowable 
level. Things such as eggshell strength or other fertility problems 
for birds or mammals must kick in at some level rather lower than that 
at which half are killed.
 
Now:
   In fish exposed to 2.0 mg/L of Roundup the fillets contained 80 mg/kg
   of glyphosate and the eggs contained 60 ug/kg. Also, significant
from:    Linkname: Herbicide Bibliography
        URL: http://www.powerlink.net/fen/herb.htm
 
I don't think that that would be ug, i.e. microgram per kilogram, of 
which 60 is 60 parts per billion? I think it is going to be milligrams, 
giving the parts per million. How often do micrograms and milligrams get 
confused? Quite frequently I think. 
 
If the mallard ducks are eating that fish at 80 mg/kg, that would seem 
to be only about 50 times that to be lethal to half of them. Could the 
infertility &c be kicking in?
 
It may not be only the lack of food causing the reduced bird figure:
 
  18. Santillo, D.J. et al (1989), "Response of songbirds to
   glyphosate-induced habitat changes on clearcuts." JOURNAL OF WILDLIFE
   MANAGEMENT, v.53 no.1, p.64-71.
   
   This 2-year investigation selected 6 study sites in north-central
   Maine. Glyphosate was applied by helicopter at a rate of 4.7 L active
   ingredient/42.1L water/ha. The alder flycatcher and eastern kingbird
   were not included in the study because of small population.
   Insectivorous foliage gleaners, primarily common yellowthroats,
   decreased on the 2 plots treated in 1983 and in 1985. Territories of
   these birds on treated sites concentrated in areas that had been
   skipped during the spraying. Total abundance of song-birds was 36%
   lower on herbicide-treated clearcuts that were vegetationally less
   complex than untreated clearcuts for at least 3 years post-treatment."
   (p.69)
   
   Invertebrates were less abundant on treated clearcuts. There were also
   areas on all treated sites where conifers did not persist, such as
   within wet swales.
 
from:   Linkname: Herbicide Bibliography
        URL: http://www.powerlink.net/fen/herb.htm




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