Rehashed herbicides in the GM pipeline

September 2013

Monsanto superweed protester in San Francisco.
CC photo by Steve Rhodes on Flickr

The ubiquitous over-use of Roundup herbicide on GM crops in America has resulted in Roundup-resistant weeds clogging fields across the land.

Farmers who have been relying on Roundup to keep weeds down for over a decade, are now desperately in need of a new tool to deal with the problem. And, now that they've been trained, to the exclusion of all other techniques, to use a chemical to cure unwanted plant growth, that 'tool' has to be another chemical.

Predictably, the biotech industry is trotting out a new generation of crops genetically transformed to resist other herbicides. These 'other' herbicides aren't new, they're old ones which fell from favour on safety grounds when 'safe-as-salt' Roundup captured the market (see SAFE AS SALT - GMFS Archive, February 2009): with them comes a whole raft of new health threats.

Dow Chemical Company is developing GM crops which tolerate 2,4-D herbicide. Monsanto is developing GM crops which tolerate 'Dicamba' herbicide. Both these chemicals were ingredients of 'Agent Orange' defoliant used in Vietnam. Neither weed-killer has a clean safety reputation. 2,4-D is a neuro- and developmental-toxin. Dicamba damages DNA . Both come with a question mark about cancer.

Non-GM farmers in proximity to GM-planted areas have already raised serious concerns about the volatile nature of the two imminent herbicides: they are very easily carried by the wind onto conventional crops. In fact they can drift for miles: in one incident in California, 2,4-D drifted 100 miles from where it was applied, damaging 15,000 acres of cotton and pomegranate orchard along the way. Gardens and the countryside could be similarly devastated.

Dow's answer to the problem is a legal requirement for farmers to take specified precautionary measures when spraying 2,4-D. Details of these requirements haven't emerged in the media, but it's likely they specify the application nozzle size, spraying only when the winds are favourable (between 3 and 10 mph in the right direction) and rinsing out the sprayers for 45 minutes after use. How closely such specifications can be adhered to in the real world where the pesticide applicator's visit has to be scheduled some time in advance, and where water is limiting isn't clear.

Monsanto's answer has been to reformulate its Dicamba to make it less volatile and less prone to drift.

The nature of the reformulation hasn't emerged in the media.

Under pressure from a farmers' coalition, the US Department of Agriculture has been forced to carry out a full environmental impact statement on both re-hashed herbicides, which has delayed approval. However, Monsanto is already planting and spraying its Dicamba-resistant GM crops in large, field-size, 'Ground-Breaker' demonstration plots in North and South Dakota, and in research plots in undisclosed locations.

As one weed scientist warned, if other weed-killers are overused as was Roundup, there is no evidence whatsoever that weed-resistance will not evolve.

OUR COMMENT

Besides the external environment, consumers (human, animal, and gut microbes) will soon be exposed to a cocktail of all three chemicals used on GM herbicide-tolerant crops.

Add to this, the new version of Dicamba Monsanto has dreamed up to make it less volatile is suspect. What are its new qualities? Is it heavier? Is it stickier? Like the 'Roundup' formulation which is much more harmful than its active ingredient, glyphosate, is it more toxic? Has the new version been re-tested, or are regulators relying on the safety assessment of the old one? (see, for example IS GLYPHOSATE WRECKING AQUATIC LIFE? - September 2013)

There are just too many questions surrounding the safety of herbicide-tolerant GM crops and their associated chemicals for these to flow unchecked into our food chain.

Please mention all these points to your MEP.

SOURCES:

• Some farmers want more scrutiny of new Monsanto crops, St Louis Today, 18.07.13
• Ready for Dicamba Ready GM crops? Institute of Science in Society Report, 20.06.07
• 2,4-D RED Facts, www.epa.gov/oppsrrd1?REDs factsheets/.24d_fs.htm
• Marcia Ishii-Eiteman, Monsanto's new GE crops already in the ground? www.panna.org/blog/ 8.08.13