Some information on toxicity of Round Up. Research I did in the past
also pointed to neurological effects. This literature review does not
cover those studies but does discuss the link to environmental
polloution and amphibian deaths
"Last month, an environmental group petitioned Argentina's Supreme
Court, seeking a temporary ban on glyphosate use after an Argentine
scientist and local activists reported a high incidence of birth defects
and cancers in people living near crop-spraying areas. Scientists there
also linked genetic malformations in amphibians to glysophate. In
addition, last year in Sweden, a scientific team found that exposure is
a risk factor for people developing non-Hodgkin lymphoma."
http://www.scientificamerican.com/article.cfm?id=weed-whacking-herbicide-p&page=2
...But some inert ingredients have been found to potentially affect
human health. Many amplify the effects of active ingredients by helping
them penetrate clothing, protective equipment and cell membranes, or by
increasing their toxicity. For example, a Croatian team recently found
that an herbicide formulation containing atrazine caused DNA damage,
which can lead to cancer
<http://www.scientificamerican.com/topic.cfm?id=cancer>, while atrazine
alone did not...
...Glyphosate, POEA and all four Roundup formulations damaged all three
cell types. Umbilical cord cells were especially sensitive to POEA.
Glyphosate became more harmful when combined with POEA, and POEA alone
was more deadly to cells than glyphosate. The research appears in the
January issue of the journal Chemical Research in Toxicology.