GM Free Cymru

Crucial paper 17: 
Glyphosate residues in food can cause vertebrate malformations and spontaneous abortions

Note:  This is a hugely important paper which shows for the first time  the precise mechanism involved in the malformations and spontaneous  abortions being reported in communities where pregnant women (for  example, in Argentina and Paraguay) are exposed to excessive doses of  Roundup associated with the spraying of RR soy.  Other papers  (including those from Prof Seralini and his group) have also  highlighted the toxic effects of glyphosate-based herbicides.  The  findings of the Carrasco group have caused so much concern in the GM  soy industry that Prof Carrasco has been the target of (yet another)  campaign of vilification, involving intimidation and hired thugs, into  which Amnesty International has now been drawn.  Monsanto is clearly  implicated. 
See also:HIRED THUGS SEEK TO SILENCE CARRASCO and Glyphosate whistle-blower comes under sustained attack Pusztai 1999 - Carrasco 2009

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Glyphosate-Based Herbicides Produce Teratogenic Effects on Vertebrates by Impairing Retinoic Acid Signaling

Alejandra Paganelli, Victoria Gnazzo, Helena Acosta, Silvia L. López, and Andrés E. Carrasco*

Laboratorio de Embriología Molecular, CONICET-UBA, Facultad de Medicina, Universidad de Buenos Aires, Paraguay 2155, 3° piso (1121), Ciudad Autónoma de Buenos Aires, Argentina

ReceiVed May 20, 2010 Chem. Res. Toxicol. XXXX, xxx, 000

ABSTRACT

The broad spectrum herbicide glyphosate is widely used in agriculture worldwide. There has been ongoing controversy regarding the possible adverse effects of glyphosate on the environment and on human health. Reports of neural defects and craniofacial malformations from regions where glyphosatebased herbicides (GBH) are used led us to undertake an embryological approach to explore the effects of low doses of glyphosate in development. Xenopus laeVis embryos were incubated with 1/5000 dilutions of a commercial GBH. The treated embryos were highly abnormal with marked alterations in cephalic and neural crest development and shortening of the anterior-posterior (A-P) axis. Alterations on neural crest markers were later correlated with deformities in the cranial cartilages at tadpole stages. Embryos injected with pure glyphosate showed very similar phenotypes. Moreover, GBH produced similar effects in chicken embryos, showing a gradual loss of rhombomere domains, reduction of the optic vesicles, and microcephaly. This suggests that glyphosate itself was responsible for the phenotypes observed, rather than a surfactant or other component of the commercial formulation. A reporter gene assay revealed that GBH treatment increased endogenous retinoic acid (RA) activity in Xenopus embryos and cotreatment with a RA antagonist rescued the teratogenic effects of the GBH. Therefore, we conclude that the phenotypes produced by GBH are mainly a consequence of the increase of endogenous retinoid activity. This is consistent with the decrease of Sonic hedgehog (Shh) signaling from the embryonic dorsal midline, with the inhibition of otx2 expression and with the disruption of cephalic neural crest development. The direct effect of glyphosate on early mechanisms of morphogenesis in vertebrate embryos opens concerns about the clinical findings from human offspring in populations exposed to GBH in agricultural fields.