Dicamba - Worse Than Glyphosate

October 2021 

 

After all the whitewashing of glyphosate herbicide revealed when its manufacturer, Monsanto, was taken to court by users who now have cancer [1], it should come as no surprise that dicamba herbicide [2] looks like being a re-run of the same story.

Dicamba-tolerant GM crops entered the market few year ago to replace the wildly successful glyphosate-tolerant versions. This wasn't because of the cancer problem, but due to the widespread emergence of glyphosate-resistant weeds. The new GM crop/herbicide package is being brought to market by a collaboration of Bayer (subsequent to its purchase of Monsanto) and chemical giant BASF.

In contrast to glyphosate-based herbicides, such as Roundup, dicamba is tricky to handle: it's volatile and can very easily be blown far off-target, especially in hot weather. However, Monsanto and BASF assured regulators that they would bring "really good farmer-friendly (dicamba) formulations to the market place" which along with training for applicators, special nozzles, buffer zones and good stewardship would control the volatility problem.

Dicamba labelling instructions are so complex that according to one farmer "There doesn't appear to be any way for an applicator to be 100% legal in their application." No doubt this suits industry very well because it means the blame for any problems can be laid on the farmer for not following the rules.

It didn't take long for dicamba damage in the field to lead to court action. During the first dicamba damages trial, Company documents revealed a cynical prioritisation of profits over farm welfare and a full knowledge of the issues the new GM crop system was bound to generate.

Agricultural experts were already warning Monsanto back in 2009 that farmers would spray the older, volatile versions of dicamba on GM crops, and that the newer herbicide formulations would still drift, with catastrophic consequences. It was clear that the company fully expected "off target movements", "crop loss", and "lawsuits". In fact, in 2015 Monsanto's own projections for the first five years of GM dicamba-tolerant crop use estimated over 10,000 claims at a cost of some $15 million.

Despite these warnings, both companies were excited about the profit potential of the dicamba/GM-crop system. BASF predicted its new dicamba herbicide would be a "$400m brand in two years", with a 45% gross profit.

Comment. With annual profits like that on the horizon, the $15 million price-tag for damages pales to insignificance.

The reality down on the farm has been "wall-to-wall" damage, with some farms being hit by dicamba spray drift multiple times, and the newly developed herbicide formulations don't seem to have helped much. This, it seems, was part of a cynical strategy on the part of Monsanto and BASF to gain "market opportunity" from "defensive planting" of GM dicamba-resistant seeds by farmers who had suffered drift damage to their conventional crops.

Monsanto and BASF also devised a plan to get round the spray-drift problem by asking the US Environmental Protection Agency (EPA) to allow some level of dicamba to be legalised in accidentally exposed crops such as tomatoes, potatoes and grapes.

Scrutiny by independent scientists seems to have been blocked so as to avoid inconvenient data that might have worried the regulators. One weed scientist who requested a very small quantity of the new dicamba formulation for testing was told by Monsanto that it was "not testing formulation this year because of the difficulty in producing quantities that would allow for broader testing". If it sounds unlikely that a company as large as Monsanto could have had production limitations on a blockbuster chemical which had been around since the 1960s, one of its technology production managers responded ""Hahaha. Difficulty in producing enough product for field testing. Hahaha bullshit."

Both companies stick firmly to the mantra that their products are safe and effective when used correctly.

'Safety', of course, is the key issue.

The question of 'safety' for other farmers' crops doesn't seem to have been a serious issue for either company. And, despite the many years dicamba has been used in conventional agriculture, the question of safety for users is only recently getting answers.

Updated data from the American Agricultural Health Study* has indicated a long-term link between farm workers who have applied dicamba and several cancers, including liver and bile-duct cancer, leukaemia, and an aggressive form of Non-Hodgkin Lymphoma.

*The American Agricultural Health Study is an on-going, long-term study of nearly 50,000 farm workers in two major US farming states. It has been gathering data on health and pesticide exposure since 1993, before the advent of GM crops. Data are updated periodically, and the latest follow-up now being published covers 2014-2015.

Since most cancers have a lag-phase of years or decades between exposure to the carcinogen and manifestation of symptoms, the latest data are the most likely to reveal problematic agrichemicals.

Previous animal studies found that:

"dicamba can alter liver function in a way that is known to induce liver tumours and promote liver cancer in combination with other carcinogens. Dicamba is also known to cause DNA mutations and induce oxidative stress, two pathways known to cause cancer" (GM Watch).

As one scientist at the Center for Biological Diversity pointed out "With dicamba's ability to drift for miles, people in many areas of the country are now routinely forced to breathe in this dangerous pesticide", and the Agricultural Health Study "exposes the terrible human cost of the EPA's reckless decision to expand the use of dicamba". 

The latest information from the US weed scientists is that pigweed (Palmer amaranth), one of the most problematic weeds in US fields, is becoming resistant to dicamba. Some pigweed populations have been observed starting to recover just a few days after dicamba application and to resume growth 2-3 weeks later.

Comment. This heralds progressive increases in spraying with dicamba and/or more toxic herbicide cocktails. Just like glyphosate.

OUR COMMENT

The effects of increased dicamba residues in our environment and food aren't known, and it's too early for any surge in cancers resulting from GM-linked dicamba exposure to emerge. There's also the unexplored possibility that dicamba could induce another layer of catastrophic epigenetic effects on future generations [3].

The solution? Get off the agrichemical GM crop treadmill.

Raise all these issues with your representative in government.

Background

[1] ROUNDUP ON TRIAL - May 2019 

[2] OLD DICAMBA, SAME OLD PROBLEMS - July 2019

[3] EPIGENETIC MAYHEM COURTESY OF GLYPHOSATE - September 2021


SOURCES

• Carey Gillam, Revealed: Monsanto predicted crop system would damage US farms, Guardian, 30.03.20
• Catherine C. Lerro, et al., May 2020, Dicamba use and cancer incidence in the agricultural health study: an updated analysis, International Journal of Epidemiology
• National Institutes of Health study links dicamba to increased cancer risk, GM Watch 5.05.20
• Nathan Donley, National Institutes of Health Study Links Dicamba, Increased Cancer Risks, Center for Biological Diversity Release, 4.05.20 
• Emily Unglesbee, Dicamba Not Controlling Some Tennessee Palmer Amaranth Populations, DTN Progressive Farmer, 27.02.20 
• Court shoots down US EPA approval of dicamba pesticide, GM Watch, 4.06.20

Photo: Dicamba drift damage to soybean crop. From Creative Commons