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From:
"Krell, Rainer (NRC)" <[log in to unmask]>
Reply To:
Krell, Rainer (NRC)
Date:
Wed, 11 Jul 2012 14:26:28 +0200
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Dear All,

"Money buys anything" A false statement that seems to become more truthful as time goes by or as it is repeated.

I know it is an old argument, but some people still believe the advertisement and the pro-GM propaganda.

"An experimental protocol that cannot detect toxicity of a pesticide on a target species is clearly not fit for testing potential harm to non-target species." For more see below   

Alternative: the registration as a pesticide should be withdrawn.

Make sure you do not eat any of those products, directly or indirectly :-)

Rainer   



-----Original Message-----
From: [log in to unmask] [mailto:[log in to unmask]] 
Sent: 11 July 2012 09:21
To: Krell, Rainer (NRC)
Subject: Bt Toxicity Confirmed: Flawed Studies Exposed

The intended recipient for this message is [log in to unmask] The Institute of Science in Society Science Society Sustainability http://www.i-sis.org.uk

This article can be found on the I-SIS website at http://www.i-sis.org.uk/Bt_Toxicity_Confirmed_Flawed_Study_Exposed.php

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========================================================
ISIS Report 11/07/12
Bt Toxicity Confirmed: Flawed Studies Exposed #############################################

Researchers confirm Bt toxicity to non-target beneficial insects and show how experiments claiming to refute their results were designed not to find the effect. Dr Eva Sirinathsinghji

A new study confirms that the Cry1Ab Bacillus thuringiensis (Bt) toxin present in genetically modified (GM) crops kills the larvae of the two-spotted ladybird (Adalia bipunctata L.), a species that GM supporters claim to be unaffected by the toxin [1].  

The study raises questions regarding the integrity of previous work published by GM proponents, whose experimental protocols were re-tested and shown to lack the scientific rigour required to pick up signs of toxicity even in target insects that the pesticide is designed to kill.

Bt toxins are present in many GM crops including cotton and maize. Monsanto's Mon 810 Bt maize is currently approved for cultivation in Europe, although it has been banned by individual nations including Hungary, France, Austria, Germany, Greece and Luxembourg due to health and environmental concerns. Many previous studies have found effects on health and the environment (see [2] Bt Crops Failures and Hazards, SiS 53, [3] More Illnesses Linked to Bt Crops, SiS 30). 

Previous Bt toxicity studies slandered by GM proponents

GM proponents claim that certain Bt toxins are effective against limited orders of insects, with Cry1Ab killing only Lepidoptera (butterflies and moths) such as the common maize pest the European cornborer. However, a peer-reviewed study published by Angela Hilbeck and colleagues at the Swiss Federal Institute of Technology in 2009 showed increased mortality in ladybirds exposed to the 'activated' toxin that had been coated on their food - meal moth eggs [4]; the team had found similar effects in green lacewings previously [5-7]. The activated version refers to the cleavage of the pro-toxin to produce the actual toxin.

In response to their original publication, a coordinated effort aimed at discrediting their findings appeared in the journal Transgenic Research, which included two highly charged critiques [8, 9] and a study led by Jörg Romeis from Agroscope, Switzerland, which failed to detect any toxicity [10]. They concluded that the results of Hilbeck's team were 'false-positives' and artefacts of a poor study design. One critique went as far as suggesting the work was 'pseudo- science'. Agroscope, a Swiss federal governmental research organisation, is linked to the agrotech giant Syngenta, which along with Monsanto, produces Cry1Ab GM crops. These hostile attacks were triggered by the ban of Mon 810 maize in Germany based on results obtained by Hilbeck's team among 30 other scientific publications showing harmful effects from the pesticide.

Addressing discrepancies between previous studies

The new work from Hilbeck's team aimed to address the discrepancies between their own findings and those of their critics. First they conducted a 'proof-of- concept' experiment where they tested both their original protocol and Agroscope's protocol on the target species, the European cornborer. 

In the Hilbeck team's original study, the ladybird larvae were exposed continuously for 10 days to a microbially-produced purified version of Cry1Ab or a microbially produced 'empty' version lacking the toxin. They were exposed through coating their food - meal moth eggs - with the toxin. The Agroscope protocol on the other hand, exposed the larvae for only 24 hours at a time through a sugar/water droplet with or without the toxin. As the larvae are carnivorous and cannot survive on a sugar diet alone, they were transferred to petri dishes with untreated moth eggs, thus giving them a period to recover from the exposure. This exposure/recovery was apparently repeated 4 times in total. 

So, the aim of the new study was to understand if the differences in these protocols may have accounted for the opposing results obtained by Hilbeck's team and by Agroscope. By testing target species that the toxin is designed to kill, any weakness in the protocol would become apparent. 

Hilbeck's team repeated the basic protocols by exposing 4 day old larvae to Bt maize as well as near isogenic non-GM maize sprayed with Bt toxins either continuously for 7 days, or for 24 hours followed by untreated non-transgenic maize for 6 days. They found high levels of mortality following continuous exposure as expected (just below 100 % with both types of exposure). The mortality rates dropped by half when animals were exposed to Bt sprayed plants for 24 hours only. Exposure to Bt maize for only 24 hours did not even cause mortality rates to rise above unexposed control groups.

An experimental protocol that cannot detect toxicity of a pesticide on a target species is clearly not fit for testing potential harm to non-target species. 

In addition to insufficient exposure time, other flaws in the Agroscope experiments were noted by Hilbeck. Sugar/water droplets to which Bt toxin was added were found to dry up overnight, leaving the levels of exposure undetermined. Only one dose was tested, as opposed to three tested in the original study by Hilbeck's team [4]. There was no clear description of the number of animals used or the number of times the experiments were replicated, whereas performing 3 replicates is standard in laboratory studies. 

Read the rest of this report on the ISIS website http://www.i-sis.org.uk/Bt_Toxicity_Confirmed_Flawed_Study_Exposed.php

Or read other ISIS reports on genetic engineering in agriculture http://www.i-sis.org.uk/GE-agriculture.php

If you find this report useful, please support ISIS by subscribing to our magazine Science in Society, and encourage your friends to do so. 
http://www.i-sis.org.uk/subscribe
Or have a look at the ISIS bookstore for other publications http://www.i-sis.org.uk/onlinestore/books.php
========================================================
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