I have always had the opinion that genetically modifying a food stuff to enable more poisons (herbicides) to be applied to it is not something I would be comfortable with and I would like the opportunity to make the choice, via a label, on whether to consume it.

On the other hand there are genetic modifications like Bt in maize that enable a reduction even a complete cessation in pesticide spraying. This means less poisons in our food and less toxic run-off into our streams and rivers. I consider these a positive both for our health and our environment.

Those who look at this as a black and white issue, particularly those who deride people who have continuing concerns, really need to engage the brain the good lord gave them and do some research.

Oh, I didn't even realise I got a response. Thanks to Argronomist, Toni Lavis and Shadow Minister for saving me the effort of responding.

SteeleRedux,

Having concerns is one thing (and there are some legitimate concerns). Buying into, and spreading demonstrably false, fear-mongering claims that can be debunked by a simple Google search, is another.

Here's a brilliant, well-balanced article weighing up the pros and cons of GMO foods by one of the big names in the sceptic movement, Steven Novella.

http://theness.com/neurologicablog/index.php/the-gmo-controversy

"I have always had the opinion that genetically modifying a food stuff to enable more poisons (herbicides) to be applied to it is not something I would be comfortable with and I would like the opportunity to make the choice, via a label, on whether to consume it."

SteeleRedux, you are in luck. All products containing more than 1% GM material (other than highly refined products where no protein or DNA is present and manufacturing aids) are labelled in Australia. Unfortunately, labels don't distinguish between insect tolerance, herbicide tolerance or other traits.

GM does not necessarily allow more herbicides to be applied. The whole point of herbicide tolerant crops is to allow different herbicides to be applied. This may mean more herbicide or less herbicide. An example from Australia: Roundup Ready canola allows about 2 kg/ha of atrazine plus 120 g/ha of clethodim plus 90 g/ha of clopyralid to be replaced by about 1.2 kg/ha of glyphosate.

So to allow you to make the choice you want, you really need a label that specifies how much of each herbicide went on the crops used to make the product.

SR,

FYI, one of the selling points of roundup ready crops are that because the glyphosate can in one dose eliminate all weeds, the total volume of chemicals used to produce crops can be reduced to about 1/3rd of normal.

Dear AJ Phillips,

Thank you for the link.

Novella writes;

“The disadvantage of herbicide tolerant crops is that they increase herbicide use, which gets into the environment, and which encourages the development of resistant weeds. So what’s the net effect? That all depends on how these crops are used. Relying solely on glyphosate and glyphosate-resistant crops is turning out to be a bad idea, mainly due to the development of resistance among weeds.”

But he doesn't address the concern I raised about the health impact of digesting increasing amounts of herbicides.

Dear Agronomist,

While there were some initial reductions seen in herbicide use in the corn, cotton and soy crops in the US much of the credit was given to new tillage practices rather than the introduction of HT seeds. Since the start of the century the total herbicide use on each of these staples has markedly risen.

Dear Shadow minister,

You wrote;

“FYI, one of the selling points of roundup ready crops are that because the glyphosate can in one dose eliminate all weeds, the total volume of chemicals used to produce crops can be reduced to about 1/3rd of normal.”

Statements like these is exactly what I'm talking about. The only reason you would want to increase herbicide tolerance in a crop is so you apply more of it yet you are trying to make the case that dramatically less is required? This is simply nonsensical.

Actually Steele, while I do think that while superficially there is cause for concern about applying more chemicals such as herbicides to our food, the actualities are that doesn't really translate to residues on or in our food products.

SM is actually not non-sensical (a rare case I know) in his statements. Consider the timing of herbicide use, application can occur when the crops are still young and growing without fear of killing the crop itself. Tolerance of the crop gives far more flexibility in the times available to apply.

The GM crop allowing the timing of herbicide application to change actually ENABLES the current changes in tilling practice, i.e. no-till practices that disturb the soil less and reduce soil erosion and retain soil moisture as well as preventing weed establishment.

The timing of herbicide application also means that residues are less likely to carry over into the foostuff at harvest. Residue testing of herbicides and pesticides are actually performed and required for market access. Look up MRL (maximum residue limits) which are available for each commodity and food.

Weed reduction in cropping systems is important not only for yield, but also for reducing contamination of nasties found in weeds and weed seeds. eg: https://www.daf.qld.gov.au/animal-industries/pigs/feed-nutrition/ingredients-contaminants/toxic-weed-seeds.
In oilcrops, some of the nasties can carry over into the oil and reduce the nutritional quality of the oil, which is why GM canola oil often tends to actually be cleaner than some others.

But yes you are correct, the increase in herbicide (read: glyphosate) use is actually because of the increase in herbicide resistant crops and the availability of less residual but more broadly acting herbicide use in systems that couldn't easily use it before.

I know that you are concerned that more herbicide is being used. However, I am thankful that the herbicide is glyphosate, as it leaves less environmental residues than others.

However, as will all agricultural chemicals, resistance development in the target pests/weeds is always a huge issue, so careful use is required.