New research on the DNA-damaging effects of the popular herbicide known as Roundup® indicates that it can do significant harm to fish even after short-term, environmentally low concentration exposures in the parts per billion range (μg /L).[i]
Published this month (July, 2012) in the journal Environmental Monitoring and Assessments researchers set out to evaluate the genotoxic effects that the herbicide Roundup®, and its primary ingredient glyphosate, can have on a species of catfish known as Corydorasa paleatus. When exposed to minute concentrations of Roundup (at a concentration of 6.67 μg/L, corresponding to 3.20 μg/L glyphosate) for 3,6 and 9 days, the following effects were observed: "[T]he comet assay showed a high rate of DNA damage in group exposed to Roundup(®) for all treatment times, both for blood and hepatic cells." The researchers summarized their findings:
We conclude that for the low concentration used in this research, the herbicide shows potential genotoxic effects. Future research will be important in evaluating the effects of this substance, whose presence in the environment is ever-increasing.
First, it is very important to understand how low a μg /L or parts per billion concentration is. One way to visualize it is to think of one drop in one billion drops of water, or what amounts to one drop of water in an entire swimming pool.[ii]
Owing to the fact that glyphosate is now a ubiquitous contaminant in our environment, having been found in most U.S. air and rain samples tested,[iii] as well as being measured beyond the limit of quantification (higher than 2.5 ug/L) in 41% of 140 groundwater samples collected from Catalonia Spain, this new finding has profound implications for environmental and human health alike. With over 88,000 tons of the stuff used in the US in 2007, according to the USGS, and with an ever-expanding volume being applied to increasingly glyphosate-resistant GM crops, the problem of exposure is only going to get worse in the future – that is, if we continue to support the growth of glyphosate-dependent GM crop industries.
Monsanto, the originator of glyphosate and its most popular branded formulation, Roundup®, once marketed their herbicide "as safe as table salt," and claimed it was "highly biodegradable." These claims have now been disproved. Like Agent Orange, another Monsanto co-creation (along with Dow Chemicals, and several other government contractors), this herbicide exhibits a broad range of biocidal (life-killing) properties. (Note: the concept of a "weedkiller" is absurd. These chemicals do not selectively kill only targeted plants. Also, a "weed" is simply a plant whose virtues we have yet discovered [Emerson], or which is encroaching on a plant we favor).