28 March 2012
from I-SIS Website
It raises concerns over the safety of
inhaling glyphosate, one of the most common ways in which people are
exposed to the herbicide.
Importantly, DNA damage occurred at
concentrations below those required to induce cell damage,
suggesting that the DNA damage was caused directly by glyphosate
instead of being an indirect result of cell toxicity.
These experiments show that glyphosate herbicides are dangerous for humans and many other animals.
Glyphosate is highly soluble in water, so impacts on aquatic wildlife may be of particular concern, especially following the recent report on the presence of glyphosate in rain water, groundwater, rivers and air. Its extreme toxic effects on amphibians such as frogs has already been shown (see Roundup Kills Frogs).
Cell damage has been documented in many cell types including those derived from the rat testis (see Glyphosate Kills Rat Testes Cells), human placenta, umbilical cord, and embryo (see Death by Multiple Poisoning, Glyphosate and Roundup), rat and carp neurones, and liver .
The Roundup formulation used for the
experiments contains 450 g/L of glyphosate and should be diluted
according to the manufacturer’s instructions to 1–3 % before use
(final concentration 4 500-13,500 mg/l). The researchers found some
significant effects with 10-20 mg/l, equivalent to a 225-1,350-fold
dilution of the spraying solution.
The integrity and viability of cells was
indicated by their staining with neutral red as only healthy cells
retain the dye. Mitochondrial function was assessed by measuring the
activity of the enzyme mitochondrial dehydrogenase with the
substrate XXT that gives a yellow color product. And cell
proliferation was measured by the total protein content of the cell
With Roundup, a significant effect was
seen at a dose level of 40 mg/L with the XXT assay, while a clear
increase of the lactose dehydrogenase levels was seen already with
10 mg/L. The cell proliferation and the neutral red assays were less
responsive, with significant effects detected at 80 and 100 mg/L,
respectively (still well below agricultural use levels). All effects
Multiple tests show
Roundup causes DNA damage
Different nuclear anomalies were measured including
Significant effects on DNA integrity as
assessed by the SCGE assay were seen at 20 mg/l of both Roundup and
glyphosate, increasing in a dose-dependent manner.
The number of nuclear buds increased with exposure concentrations, starting at 10 mg/L with both glyphosate and Roundup.
In the case of the nucleoplasmic bridges,
the only significant effect was obtained with the highest dose of
Roundup used (20 mg/L). Apoptotic cells were observed following
20mg/L of Roundup but not glyphosate, while necrosis occurred in
response to 20mg/L of both Roundup and glyphosate.
The different effects between the active ingredient and its commercial formulation is consistent with previous work, including experiments done on testicular, placental, embryonic and umbilical cord cells (see above).
These results may explain some of the
ailments observed in people who work with this herbicide and adds
yet more weight to an outright ban of the herbicide (see
Ban Glyphosate Herbicides Now.)