We’ve just been alerted by Dr Jonathan Latham, Director of Programmes and Outreach of the Bioscience Resource Project to a new paper on the effects of pollen from the GM maize Bt176 on the European common swallowtail butterfly. The study shows that less than 5 grains of this Bt pollen has a negative impact on the butterfly’s life history.
The summary of the paper is given below. As it notes, uptake of Bt maize pollen led to swallowtail larvae consuming less plant material, having a lower body weight, and taking longer to develop. Larvae that consumed Bt-maize pollen also had a lower body weight as adult females and smaller forewings as adult males.
It’s also worth noting that although this is a lab study and field conditions can be different, the pollen densities in this study are in accordance with maize pollen densities found on swallowtail host plants in the field. In fact, the field densities can be much higher, notably during the pollen shedding period of maize fields. The pollen shedding time also usually spans a much longer period than the 48 hours of this study. This might suggest that the actual impact of the Bt maize pollen on butterflies might be considerably greater.
The researchers conclude that possible effects of Bt maize on European butterflies and moths must be evaluated more rigorously before Bt maize cultivation expands. It’s certainly alarming that this GM maize was approved for commercialization in 1997 and we’re now looking at the results of this simple lab study showing its negative effects 9 years later! — Bt maize effects on Papilio machaon The effects of pollen consumption of transgenic Bt maize on the common swallowtail, Papilio machaon L. (Lepidoptera, Papilionidae) Andreas Lang a, Eva Vojtech a,b a Bavarian State Research Centre for Agriculture, Institute of Plant Protection, Lange Point 10, D-85354 Freising, Germany b Institute of Environmental Sciences, University Zurich, Winterthurerstr. 190, CH-8057 Zurich, Switzerland Received 10 March 2005; accepted 31 October 2005
Summary Effects of exposure to maize pollen of event Bt176 (cultivar “Navares”) on the larvae of the European common swallowtail (Papilio machaon L.) were studied in the laboratory. First instar larvae were exposed to different pollen densities applied to leaf disks of Pastinaca sativa L. for 48 h. Pollen densities applied in this study were in the range recorded from the field. Larvae which were exposed to higher Bt maize pollen densities consumed more pollen and had a lower survival rate. The LD50 with regard to larvae surviving to adulthood was 13.72 pollen grains consumed by first-instar larva. Uptake of Bt maize pollen led to a reduced plant consumption, to a lower body weight, and to a longer development time of larvae. Effects on pupal weight and duration of the pupal period were present but less pronounced and smaller than effects on larvae. Larvae having consumed Bt-maize pollen as first instars had a lower body weight as adult females and smaller forewings as adult males. We conclude that possible effects of Bt maize on European butterflies and moths must be evaluated more rigorously before Bt maize should be cultivated over large areas.
All plantings of Bt maize in Europe are harmful and illegal Dr Brian John
Summary: IT IS NOW INCONTROVERTIBLE THAT ALL PLANTINGS OF BT MAIZE VARIETIES (eg MON810 and Bt176) IN EUROPE ARE HARMFUL AND THUS ILLEGAL UNDER DIRECTIVE 2001/18. HOW MUCH MORE EVIDENCE DO THE ‘EXPERTS’ AT DEFRA, ACRE, FSA, ACNFP, EFSA ETC. ACTUALLY NEED? ARE THEY ALL STUPID? WHATEVER THEIR PERSONAL PROBLEMS MAY BE, THEY ARE CERTAINLY GUILTY (EACH ONE OF THEM, PERSONALLY) OF THE WILFUL SUPPRESSION OF EVIDENCE AND OF CRIMINAL NEGLIGENCE.
Directive 2001/18 is enshrined in law, and every time a Bt variety is planted, cultivated or harvested (“deliberately released into the environment”) the law is being broken (1) (2).
The notes below just refer to plant toxicity, microbiology and insect life. There are other studies too (eg Bt cotton), relating to mammals including human beings. There is now so much evidence of harmful toxic effects associated with Bt varieties that all past approvals by the EC must be revisited. The approvals procedures for GM varieties “in the pipeline” must also be stopped instantly. If they are not, that would be interpreted by any reasonable person as connivance in environmental damage and in the extension of public health risk by EFSA and by Commissioners Dimas and Kyprianou in particular.
Evidence of ecological damage associated with Bt varieties is presented below from Germany, Hungary and Australia. Some of this material has been in the public domain for 2 years or more, but it has been systematically and cynically disregarded by the EC.
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(1) GERMANY
Thanks to Jonathan Latham for drawing attention to this:
Lang,A and Vojtech, E: “The effects of pollen consumption of transgenic Bt maize on the common swallowtail, Papilio machaon L. (Lepidoptera, Papilionidae), Basic and Applied Ecology 7 (2006), pp 296-306
This is a careful lab-based peer-reviewed study which used moderate pollen densities in accordance with densities found in the field. The authors point out that field pollen densities can be much higher in the pollen shedding period, which lasts from 5 – 14 days. During this period the toxic effects of Bt exposure will clearly be more marked (including greater larvae mortality rates and reduced reproductive success in butterflies) than those revealed in the study. Note that these effects are specific to Bt176 pollen — they have nothing to do with herbicide applications.
The study used Bt176 maize from the Navares (Syngenta) cultivar. The work was financed by the State Government of Bavaria.
Quotes:
“Bt toxins are produced in most tissues of the Bt maize, and pollen with toxin may be transported by wind into adjacent areas, deposited on plants, and consumed by larvae of non-target species feeding on these plants.”
“Consumption of Bt176-maize pollen had adverse effects on life history traits of the common swallowtail. P machaon larvae fed with Bt pollen had a lower survival, a lower weight increase rate, a longer development time, and lower body-weight and smaller wing size as adults, and these effects were significantly associated with Bt pollen density.”
“The study demonstrated toxic effects pf Bt176 maize pollen on P. machaon…”
“Bt consumption enhances the negative impact of bacterial infections on Lepidoptera larvae…”
“This study and the papers of Felke et al showed that the Bt176 maize has the potential to adversely effect larvae of European butterflies.”
“We conclude that possible effects of Bt maize on European butterflies and moths must be evaluated more rigorously before Bt maize should be cultivated over large areas.”