GM Free Cymru

New paper on toxicity: glyphosate bad, Roundup worse for aquatic invertebrates

Date Added to website 20th June 2013

Comment from GM-Free Cymru:

This is an important new paper which demonstrates (yet again) the toxicity of glyphosate and Roundup when present in minute amounts in the aquatic environment. It also makes the point (yet again) that the regulators within the EU and USA are guilty of severe negligence since they assume that tests on glyphosate are adequate to demonstrate the environmental impacts of Roundup. This latter commercial formulation, as pointed out several times by Seralini and his colleagues, is MUCH more dangerous than glyphosate on its own. How much more experimental evidence do EFSA and the EC actually need before they accept that their assumptions about the safety of Roundup are based upon false assumptions and scientific fraud?

Clone- and age-dependent toxicity of a glyphosate commercial formulation and its active ingredient in Daphnia magna

by Marek Cuhra, Terje Traavik and Thomas Bøhn

Ecotoxicology (2013) 22:251–262 DOI 10.1007/s10646-012-1021-1

Accepted: 15 November 2012 / Published online: 6 December 2012


Low levels of glyphosate based herbicide induced significant negative effects on the aquatic inverte- brate Daphnia magna. Glyphosate herbicides such as brands of Roundup, are known to be toxic to daphnids. However, published findings on acute toxicity show significant dis- crepancies and variation across several orders of magnitude. To test the acute effects of both glyphosate and a commercial formulation of Roundup (hereafter Roundup), we conducted a series of exposure experiments with different clones and age-classes of D. magna. The results demonstrated EC50 (48) values in the low ppm-range for Roundup as well as for the active ingredient (a.i.) isopropylamine salt of glyphosate (glyphosate IPA) alone. Roundup showed slightly lower acute toxicity than glyphosate IPA alone, i.e. EC50 values of 3.7–10.6 mg a.i./l, as compared to 1.4–7.2 mg a.i./l for glyphosate IPA. However, in chronic toxicity tests spanning the whole life-cycle, Roundup was more toxic. D. magna was exposed to sublethal nominal concentrations of 0.05, 0.15, 0.45, 1.35 and 4.05 mg a.i./l for 55 days. Significant reduction of juvenile size was observed even in the lowest test concentrations of 0.05 mg a.i./l, for both glyphosate and Roundup. At 0.45 mg a.i./l, growth, fecundity and abortion rate was affected, but only in animals exposed to Roundup. At 1.35 and 4.05 mg a.i./l of both glyphosate and Roundup, significant negative effects were seen on most tested parameters, including mortality. D. magna was adversely affected by a near 100 % abortion rate of eggs and embryonic stages at 1.35 mg a.i./l of Roundup. The results indicate that aquatic invertebrate ecology can be adversely affected by relevant ambient concentrations of this major herbicide. We conclude that glyphosate and Roundup toxicity to aquatic invertebrates have been underestimated and that current European Commission and US EPA toxicity classification of these chemicals need to be revised.


M. Cuhra, T.Traavik and T.Bøhn, GenØk, Centre for Biosafety, The Science Park, P.O. Box 6418, 9294 Tromsø, Norway Faculty of Health Sciences, University of Tromsø, Tromsø, Norway