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From: Oz <Oz@upthorpe.demon.co.uk>
Newsgroups: sci.bio.food-science,rec.gardens.edible,sci.agriculture
Subject: Re: GM Foods (link)
Date: Wed, 8 Dec 1999 10:38:45 +0000

In article <lKp34.209$B01.207@news.get2net.dk>, Torsten Brinch
<iaotb@inetdotuni2.dk> writes

>>Oz
>>Keep hare coursers away, use treated rapeseed, population of hares circa
>>2/Ha. been stable for about 15 yrs.
>
>>Give up keeping hare coursers away but (by chance) use own dressed but
>>untreated seed. Hare population (in 2 years) dropped to under 1/100Ha.
>
>>In relative risk terms the coursers seem significantly more important in
>>the scheme of things than the dressing on the seed.
>
>
>There have been instances in which 50-100 dead hares were found in
>rape fields in the autumn, apparently dead from ingestion of
>00 rape green matter.  One might hypothesize (as you originally did)
>that natural rape toxins could  have been involved (but controlled feeding
>experiments have ruled out this possibility).

I was sure at one time you said rape was responsible, however no matter
someone else presumably did.

>One can _not_
>hypotesize, however, that the mortalities had anything to do with
>coursers, so your courser observations are simply irrelevant to
>these strange wildlife mortalities.

Eh? Hypothesise? There is NO hypothesis required, you could see it
happening. By the way it's not confined to rape, it's on any field with
hares (potentially or otherwise).

We have seen them kill 20 hares in 15 minutes many times.
There really isn't any doubt that coursers have stripped the hares off
the fields. The deaths aren't unexplained, they are seen happening.
Villagers have seen the same thing many times and usually phone the
police directly using their mobiles (not that the police come out of
course)

>They are, as you say,  indeed
>interesting, and so is the way they were 'tackled'  -- (may I
>add, as I have demonstrated real interest in this particular
>subject, whereas you haven't, I do not  consider you a
>valuable dialogue partner re the subject).

I do not consider taking considerable personal risk, and putting my
family at risk to stop these people (and following the police advice
that these people are 'very dangerous' and should NOT be tackled) when
the RSPCA, when I called them stated "We are not interested in hare
coursing, we just want to stop foxhunting". If the main animal cruelty
organisation in the UK can't be bothered I am not risking a month in
hospital to do it. Mind you with 30 visits a week at peak I physically
couldn't have done it anyway.

>As to the other issue you divert yourself  into , the cause of declining
>hare populations, you should already know from previous
>discussions, what I mean about  this, i.e. that it is a multifacetted,
>and probably regionally diverse  issue, and that no one single
>cause are likely to be found to explain the decline.

Not in southern england it isn't, the evidence is just far too clear and
obvious. My offer to prove this by having any reputable wildlife
organisation keep coursers out for two years and see the rebound is
still on the table. So far no takers.

--
Oz


From: "Torsten Brinch" <iaotb@inetdotuni2.dk>
Newsgroups: sci.bio.food-science,rec.gardens.edible,sci.agriculture
Subject: Re: GM Foods (link)
Date: Thu, 9 Dec 1999 14:44:36 +0100

Alf Christophersen skrev i meddelelsen <384e4cba.1165730@nntp.uio.no>...
>"Torsten Brinch" <iaotb@inetdotuni2.dk>s tastatur skrev:

>>There have been instances in which 50-100 dead hares were found in
>>rape fields in the autumn, apparently dead from ingestion of
>>00 rape green matter.  One might hypothesize (as you originally did)
>>that natural rape toxins could  have been involved (but controlled feeding
>>experiments have ruled out this possibility). One can _not_


>I doubt that this is any acute intoxication, but rather hares dead of
>heart disease because erucic acid in rodents inhibit beta-oxidation of
>fats so they build up extensively in the heart muscles. Have a look at
>the hearts next time and compare them with a disease free heart from
>another shot, wild hare . I guess you will find some striking
>differencies.

>But in humans it turns out that the inhibition after some time is
>compensated.


Alf, the hare mortalities I am talking about has probably nothing
at all to do with erucic acid, and the hearts appeared normal
on examination.  As to the acuteness of that mystery
disease, it was so apparent to everyone involved, that the
disease (among other names) were called Acute Hare Death
(AHD) in the early days. I talked with the vet who had the responsibility
to necropsy dozens of these hares in Denmark, and he confirmed
that everything he had seen was consistent with OP poisoning.
The rape plants which could have been ingested by
the hares were all young plants, recently sprouted from seeds
containing a massive dose (1 per cent!) of a highly toxic OP
insecticide.

--
Best regards

Torsten Brinch

Email: iaotb@inetdotuni2.dk
(interpret 'dot' in domain name)








From: "Torsten Brinch" <iaotb@inetdotuni2.dk>
Newsgroups: sci.bio.food-science,rec.gardens.edible,sci.agriculture
Subject: Re: GM Foods (link)
Date: Thu, 9 Dec 1999 19:51:27 +0100

Oz skrev i meddelelsen ...
>In article <dxO34.245$vY5.122@news.get2net.dk>, Torsten Brinch
><iaotb@inetdotuni2.dk> writes
>
>>Alf, the hare mortalities I am talking about has probably nothing
>>at all to do with erucic acid, and the hearts appeared normal
>>on examination.  As to the acuteness of that mystery
>>disease, it was so apparent to everyone involved, that the
>>disease (among other names) were called Acute Hare Death
>>(AHD) in the early days. I talked with the vet who had the responsibility
>>to necropsy dozens of these hares in Denmark, and he confirmed
>>that everything he had seen was consistent with OP poisoning.
>>The rape plants which could have been ingested by
>>the hares were all young plants, recently sprouted from seeds
>>containing a massive dose (1 per cent!) of a highly toxic OP
>>insecticide.

>Ah, but in the UK until now we used Lindane (coff, splutter).

That's true. Lindane, 12-45 g per kg seed (1.2-4.5 %), according
to the man in MAFF I spoke to, also that the UK never used
isofenphos for rape  seed treatment. (There might of course
have been  the odd imported treated seed-lot from the continent.)
Anyway, no instances of  Acute Hare Death (AHD)  has occurred
in the UK, afaik.

>Now I don't use anything.


Good on you. In many (most?) cases the treatment is not
really  necessary.

>Anyway let's just consier this. Usual seedrate for canola is 3-6kg/Ha so
>if 1% is a 'toxic OP' then that's 30-60g. Now, assuming a hare weighs
>say 2kg (no idea really but that shouldn't be too far out) and it eats
>say 10 m^2 of crop (I've never noticed significant hare damage even when
>we had 2/Ha) then thats 30-60 mg even if *ALL* the OP goes into the
>leaves (which is miles wrong). That would suggest an acute toxicity of
>say 40ug/2kg or 20mg/kg or something very hugely toxic that I don't
>believe is remotely likely to have been licensed.


Right. It shouldn't have been licensed, but it was. It can be said to the
excuse of the Danish 'practise of agricultural art',  that the seed we
produced for _export_, e.g. to Germany and France, got double-dose
of the stuff -- "that was about as much we could possibly make stick
to the seed",  a guy from a  Danish seed  company told me, "we
thought it was unnecessary but that was what they wanted."

>So which OP do they use in dk?

For seed treatment of oil seed rape?  No OP, that I am aware
of, none in the 1990's. Not since isofenphos was withdrawn.
There might be the odd imported seed lot, of course.

--
Best regards

Torsten Brinch

Email: iaotb@inetdotuni2.dk
(interpret 'dot' in domain name)





From: "Torsten Brinch" <iaotb@inetdotuni2.dk>
Newsgroups: sci.bio.food-science,rec.gardens.edible,sci.agriculture
Subject: Re: GM Foods (link)
Date: Sun, 12 Dec 1999 03:28:25 +0100

Oz skrev i meddelelsen ...
>In article <Muu44.135$oa1.796@news.get2net.dk>, Torsten Brinch
><iaotb@inetdotuni2.dk> writes
>>Oz skrev i meddelelsen ...
>>>In article <PcT34.369$vY5.612@news.get2net.dk>, Torsten Brinch
>>><iaotb@inetdotuni2.dk> writes
>>
>>>><..> Lindane, 12-45 g per kg seed (1.2-4.5 %), according
>>>>to the man in MAFF I spoke to, also that the UK never used
>>>>isofenphos for rape  seed treatment. (There might of course
>>>>have been  the odd imported treated seed-lot from the continent.)
>>
>>>LD50 (rats) 20mg/kg. Hmmm. Allowing for a more sensible estimate
>>>I would still think it would be difficult for a hare to get this much.
>>
>>Why?
>
>Because I doubt that more than about 20% would ever get into the leaves.

So?

>Don't forget that the dressing is surface applied and (usually) uptake
>is via the roots, the canola seedcoat is pretty tough judging from the
>vast quantities that appear in our slurry from the rapemeal.

>>I think you meant to say that you would not use lindane anyway.

>No, I meant to say that I would not treat my seed with anything since I
>think it pointless under the conditions I sow judging from my experience
>to date (3 yrs + 15ish yrs of volunteers).

>>The recent UK ban on lindane (when did/will it come
>>into effect, btw?)

>Very abruptly just before canola harvest. It caused a huge problem that
>could have been solved with 6mts warning.

>>is of course quite unlikely to affect the
>>health of a non-existing (due coursers) hare population,

>I cn't be bothered to look it up but I doubt the lindane was ever a
>significant risk to hares anyway.

After having been bothered to look into it, I must disagree, Oz.
Leaves from recently sprouted rape from lindane treated
seeds could easily carry 100-200 ppm lindane. Obviously
unhealthy fodder for a hare. It is a good  thing that this practise
has been stopped.

>Kinda sad that one switches from a safe pesticide to a dangerous one for
>safety reasons. Ah, well.

And which dangerous pesticide would be on your  mind here?

--
Best regards

Torsten Brinch

Email: iaotb@inetdotuni2.dk
(interpret 'dot' in domain name)


From: "Torsten Brinch" <iaotb@inetdotuni2.dk>
Newsgroups: sci.bio.food-science,rec.gardens.edible,sci.agriculture
Subject: Re: GM Foods (link)
Date: Sun, 12 Dec 1999 13:34:10 +0100

Oz skrev i meddelelsen ...
>In article <6fK44.43$a46.367@news.get2net.dk>, Torsten Brinch
><iaotb@inetdotuni2.dk> writes

>>After having been bothered to look into it, I must disagree, Oz.
>>Leaves from recently sprouted rape from lindane treated
>>seeds could easily carry 100-200 ppm lindane. Obviously
>>unhealthy fodder for a hare.

>It'ud be a busy hare that could eat enough cotyledon leaves and get a
>meal.


Collecting young plant material is what a hare is doing for a living,
expect it to be good at it.

>>It is a good  thing that this practise
>>has been stopped.

>URL?


Sigh. I was making reference to _your_ information, that lindane
treatment of rape seeds have been banned in the UK. You did
not present an URL, but here is the news release from your ministry:
http://www.maff.gov.uk/inf/newsrel/1999/990708d.htm

>>>Kinda sad that one switches from a safe pesticide to a dangerous one for
>>>safety reasons. Ah, well.

>>And which dangerous pesticide would be on your  mind here?

>isofenphos I guess.


That does not make sense at all, Oz. The UK has not stupidly licensed
isofenphos now, has it, nor is it planning to switch to it. In the case of
Denmark, isofenphos was deregistered already in 1990 -- several
years before lindane was finally banned.

--
Best regards

Torsten Brinch

Email: iaotb@inetdotuni2.dk
(interpret 'dot' in domain name)







From: "Torsten Brinch" <iaotb@inetdotuni2.dk>
Newsgroups: sci.bio.food-science,rec.gardens.edible,sci.agriculture
Subject: Re: GM Foods (link)
Date: Sun, 12 Dec 1999 23:40:09 +0100

Oz skrev i meddelelsen ...
>In article <hJM44.130$a46.559@news.get2net.dk>, Torsten Brinch
><iaotb@inetdotuni2.dk> writes
>
>>Collecting young plant material is what a hare is doing for a living,
>>expect it to be good at it.
>
>Not at coltyledon leaf stage. To get the several hundred grammes needed
>for a meal would take a heck of a lot of nibbles. Hmm let's see. 5kg/Ha
>is 0.5g/m^2 and with a plant population of say 250seeds/m^2 that's 250
>nibbles to get probably 0.5 g/250 nibbles (DM to fresh). To get 200g
>would need 100,000 nibbles. At a nibble per 2 secs (a darned good rate
>to keep up all day) that would take 55 hours of continuous grazing to
>get a definitely non-lethal dose meal. The animal would starve to death
>if it chose this strategy.


Your arithmetic fails you. If we, as a worst case, should assume that all
isofenphos applied to seeds treated at 2 % are taken up in the plants,
a 2 kg hare would need to nibble only 400 times (each nibble represents
one plant from one seed, and one seed = 5 mg)  to get an intake of
40 mg isofenphos, which could well be lethal.  But let us say that  a
more reasonable 10 % of the applied isofenphos dose is taken up
by the plant. Our hare would then need to nibble 4000 times to get
a lethal dose.

From sampling of emerged seedlings for lab analysis, I know that I
am able to 'nibble' 100 seedlings in less than 5 minutes. Nibbling
4000 seedling should thus take me at most 200 minutes = 3 hours
and 20 minutes. I certainly expect a hare to be as swift a sampler as I,
if not swifter.

Add to this, that with the kind of toxic effect which isofenphos causes,
it does not really matter whether those 4000 nibbles are  done during
one nights feeding or they are distributed on several consecutive nights.


--
Best regards

Torsten Brinch

Email: iaotb@inetdotuni2.dk
(interpret 'dot' in domain name)





From: "Torsten Brinch" <iaotb@inetdotuni2.dk>
Newsgroups: sci.bio.food-science,rec.gardens.edible,sci.agriculture
Subject: Re: GM Foods (link)
Date: Sun, 12 Dec 1999 16:16:59 +0100

Harold Lindaberry skrev i meddelelsen <385398C3.7A3B521A@epix.net>...
>Torsten Brinch wrote:
>>Oz wrote:

>> >I cn't be bothered to look it up but I doubt the lindane was ever a
>> >significant risk to hares anyway.

>> After having been bothered to look into it, I must disagree, Oz.
>> Leaves from recently sprouted rape from lindane treated
>> seeds could easily carry 100-200 ppm lindane. Obviously
>> unhealthy fodder for a hare. It is a good  thing that this practise
>> has been stopped.

>Gamma BHC is not translocated and thus would probably not reach that
>level

Well, but it does, Old Grey, and I have measured it myself on several
occasions. The highest concentrations are present  during
the first days after emergence, after which the concentration falls
off to about 10-20 ppm about 2-3 weeks after emergence.
Most of the lindane to be found in the young rape plants has already
been impregnated into the cotyledons during the _treatment_ of seeds,
or is transported there as vapor during the period in which seeds are
stocked before sowing. Translocation _after_ sowing, from root uptake,
is indeed a minor protection mechanism with gamma HCH, but it does
in fact contribute  to the keeping of plants insecticidal for the first
few weeks. During the first week with hi-conc from the direct contamination,
the contribution from translocation is of course rather drowned out
so as to be insignificant, but later on it isn't.

>but based on my recollection of the toxicity studies 200 ppm would not
>cause moralities.

I never said it did, but I will say that it would be expected to cause harm.
Harold, please consider the wisdom of comparing a hypothetical
rat study with 200 ppm lindane in dry  feed with a field
experiment with hares ingesting wet feed at 200 ppm.

>foliage applications of BHC were not detectable after a 14
>day waiting period thus I would not expect long term residues in any event


The possibility for long term residues is irrelevant. The risk to
hares are impliedly short term, as hares only tend to eat young
rape plants and seedlings. And with access to just a primitive TCD GC
one can easily extract and detect lindane in the ppms more than
4 weeks after emergence of rape/canola plants from seeds which
have been treated with lindane.

--
Best regards

Torsten Brinch

Email: iaotb@inetdotuni2.dk
(interpret 'dot' in domain name)







From: "Torsten Brinch" <iaotb@inetdotuni2.dk>
Newsgroups: sci.bio.food-science,rec.gardens.edible,sci.agriculture
Subject: Re: GM Foods (link)
Date: Sun, 12 Dec 1999 17:46:03 +0100

Harold Lindaberry skrev i meddelelsen <3853C3E4.A2ED43B8@epix.net>...
>Torsten Brinch wrote:


>> >> Leaves from recently sprouted rape from lindane treated
>> >> seeds could easily carry 100-200 ppm lindane. Obviously
>> >> unhealthy fodder for a hare. It is a good  thing that this practise
>> >> has been stopped.

>> >Gamma BHC is not translocated and thus would probably not reach that
>> >level

>> Well, but it does, Old Grey, and I have measured it myself on several
>> occasions. The highest concentrations are present  during
>> the first days after emergence, after which the concentration falls
>> off to about 10-20 ppm about 2-3 weeks after emergence.
>> Most of the lindane to be found in the young rape plants has already
>> been impregnated into the cotyledons during the _treatment_ of seeds,
>> or is transported there as vapor during the period in which seeds are
>> stocked before sowing. Translocation _after_ sowing, from root uptake,
>> is indeed a minor protection mechanism with gamma HCH, but it does
>> in fact contribute  to the keeping of plants insecticidal for the first
>> few weeks.

>The translocation that I was referring to was root up take, Certainly
>cotyledon up take is probable due to volatility and also possible in warm
>or hot soils up to  leaf surfaces near the soil

You misunderstand. A rape seed is a seed coat encapsulating two
curled-up diminutive cotyledons composed of about 40 % fat. The main
reason that lindane treatment of the seeds is highly protective against
insects is that lindane is able to penetrate directly into the seed during
and after the treatment of the seed, but before the seed is even sown
into the soil or has sprouted.

>but IMO significant plant
>residues from seed treatments to crop residues is unlikely at harvest
>time

That is true, but I can't see how that observation can be relevant to
asessment of wildlife risks due to expected high residues from seed
treatments present in a period shortly after sowing, and months
before harvest.

>or even a few weeks after planting. Not being that familiar with
>rape seed planting rates how much chemical is involved per acre ?

With lindane it could be ~20-150 gram per acre, depending of the
application rate of the lindane treatment on seeds, and the seed
rate per acre.




--
Best regards

Torsten Brinch

Email: iaotb@inetdotuni2.dk
(interpret 'dot' in domain name)





From: "Torsten Brinch" <iaotb@inetdotuni2.dk>
Newsgroups: sci.bio.food-science,rec.gardens.edible,sci.agriculture
Subject: Re: GM Foods (link)
Date: Sun, 12 Dec 1999 23:03:32 +0100

Oz skrev i meddelelsen ...
>In article <v8P44.223$a46.747@news.get2net.dk>, Torsten Brinch
><iaotb@inetdotuni2.dk> writes
>
>>Well, but it does, Old Grey, and I have measured it myself on several
>>occasions. The highest concentrations are present  during
>>the first days after emergence, after which the concentration falls
>>off to about 10-20 ppm about 2-3 weeks after emergence.

>Frankly I doubt any hare would bother with cotyledon leaves in the first
>days after emergence. If they did then they would have to eat a huge
>number and that would surely be very visible. In practice they graze the
>hedgerows until the plants are a reasonable size (several true leaves).


Studies of hares in the field has shown that hares will eat rape seed
plants straight from emergence and until the plants are 20-25 cm tall,
thereafter they only use the crop for cover, unless desperately hungry.
From personal observation I know that hares simply adores freshly
emerged seedlings of volunteer rape. I see no reason why they
should like, and search out, newly emerged sown rape any less.

>This is probably because it would take days to get a meal, whilst on the
>field edges it takes very little time.

Dunno how bountiful the field edges could be in  august-september
in your place in Middle to South England. Where I come from field edges
are -- at that time of year --quite a useless place to look for the kind of
food which hares eat. And so is most of the agricultural area for that
matter.  It is only when first volunteer rape, then winter sown rape and
grains emerge on the fields, that the typical late summer food shortness
for our hares is alleviated.

>This would probably not be true of pigeons but they don't attack winter
>rape at that time of year (but do spring rape).


Which time of year are you alluding to? In Denmark there is a documented
mortality episode during autumn with wood pigeons, in which scores of
dead birds were found after grazing green rape. Just like our hares, the
wood pigeons seem to be very fond of volunteer or newly sown oil
seed rape.

>I think we will have to differ on this.


You may differ all you wish, but _just_ differing is so very feeble.
Valid arguments, should you have any, would be much more
welcome.


--
Best regards

Torsten Brinch

Email: iaotb@inetdotuni2.dk
(interpret 'dot' in domain name)





From: "Torsten Brinch" <iaotb@inetdotuni2.dk>
Newsgroups: sci.bio.food-science,rec.gardens.edible,sci.agriculture
Subject: Re: GM Foods (link)
Date: Thu, 9 Dec 1999 20:06:32 +0100

Harold Lindaberry skrev i meddelelsen <384FD1E8.2CAF14FD@epix.net>...
>Torsten Brinch wrote:


>><..> The rape plants which could have been ingested by
>> the hares were all young plants, recently sprouted from seeds
>> containing a massive dose (1 per cent!) of a highly toxic OP
>> insecticide.

>    It appears as though with the 1% dose the farmer may have
>been trying to get rid of hares and succeded in his efforts
>a simple choliesterase test should have given the answer ?


Depending of the state of the corpses tests might have given
the answer. Apparently none were performed. The disease
presented itself with unspecific finds but with a tendency
to liver dystrophy/necrosis, the causes of which was in
focus.

--
Best regards

Torsten Brinch

Email: iaotb@inetdotuni2.dk
(interpret 'dot' in domain name)




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