The Muddled Debate About Pesticide Use And GM Crops

Does the adoption of GM crops lead to more or less pesticide use?  This is a frequent topic of debate, but generally one that misses the point.  Both sides make the same erroneous assumption that all pesticide use is, by definition, a bad thing.  In fact, it depends on the particular pesticide in question, the reason it is being used, and the details of its application.  Most modern pesticides are extremely low in hazard to us or to the environment.  Both "sides" of the GM debate would do well to stop over-simplfying this issue.

What Biotech Can and Can't Do

In his recent speech expressing regret for his former role in the anti-GMO campaign, environmentalist Mark Lynas cited cases where biotech crops reduced the need for pesticide applications (e.g. Bt Cotton and Bt Maize).  The examples are quite positive from the farmer's point of view.  However, for crops with biotech insect resistance, pesticides remain an important and well regulated tool for farmers who still have to deal with many other pests for which there may never be a biotech solution.   The supporters of crop biotechnology need to maintain the perspective that biotech traits are simply one tool in the tool box.  There is no excuse for ignoring the science behind advances in pesticide risk management any more than for ignoring the science behind risk management for GM technology.

Putting "Increased Pesticide Use" Into a Global Perspective

Jason Mark recently posted a "rebuttal" to Lynas' speech on Earth Island Journal.  It relied on exactly the sort of "self referencing" sources that Lynas critiqued, but one argument struck me as sufficiently absurd to warrant a response:

"A peer-reviewed study published last year in Environmental Sciences Europe found that GM plantings in the United States led to a 7 percent increase in chemical spraying."

Seriously? A European publication expressing angst about an incremental change in US pesticide use on its major crops? Do they know about the intensive use of pesticides on crops in Europe? (see graph below).  Actually, it is the study by Chuck Benbrook of the Organic Center in the US which generates a seemingly large number until you consider that his model includes use on hundreds of millions of acres over 16 years).


Why do European farmers use so much pesticide?  The reason is simple: they have to deal with lots of pests!  As with farmers everywhere, those in Europe face insects, weeds, fungi, bacteria and viruses which, if uncontrolled, diminish the amount of food that they can produce.  They farm in a generally wetter climate, and so they need lots of fungicides.  Like any farmer, they use the highly regulated pesticide options available to them so that they can limit the damage from those pests.  If they didn't use those pesticides, they would be making inefficient use of their land and of other necessary inputs like fertilizers and fuel.  As it is, Europe imports a great deal of its food and feed (206 million metric tons for the top 20 commodities imported in 2010).  When European farmers use pesticides to be as productive as possible, they at least help to minimize that strain on the global food supply.

Putting "Increased Pesticide Use" Into Quantitative And Contextual Perspective

The 7% increase Environmental Sciences Europe cites as an offshoot of GM crops mainly involves a herbicide, glyphosate, which happens to have a benign profile in terms of toxicity to things other than plants.  The transition to glyphosate for "Roundup Ready"crops replaced the use of sulfonyl ureas, a class of herbicides which had extremely low use-rates.  Thus, the still modest glyphosate use rate of 22-44 ounces of product per acre represented a small increase in total "pounds on the ground." Ken Cook of the Environmental Working Group responded to Lynas with a post in which he describes these crops as being "slathered with chemicals."  The 44 ounce rate means that each liquid ounce is spread over an area of almost 1,000 square feet. The active ingredient is applied at less than 0.01 grams per square foot.  Somehow, that does not fit my mental image of "slathered."

The far more relevant point is that glyphosate tolerant crops represented a more practical alternative to mechanical tillage for weed control and enabled wider adoption of "no-till" farming.  That is a system which conserves soil moisture, prevents erosion, dramatically reduces nutrient and pesticide movement to streams and rivers, and reduces fuel use.  If biotechnology and herbicides can combine with sophisticated equipment to enable this sort of farming - all the better.

Bottom line, a biotechnology trait may decrease or increases the need for a pesticide.  There will also be many cases where the biotech trait has nothing to do with pesticide use.  There is no necessary good or bad linkage between these two categories of agricultural technology - both can serve to make crop production better.  Both are options that should be available to those who farm.

You are welcome to comment here and/or to write me at savage.sd@gmail.com.  My Twitter feed is @grapedoc

Sprayer image from North Carolina Crops

Eight Technologies Keeping A Carcinogen Out of Your Food

Safe, Tasty, Nutritious Almonds We Shouldn't Take For Granted

Sometimes we need to hear about things that are working well in our food system.  I'd like to describe a case where sound regulation and well-applied technology combine to protect us from a significant risk posed by a natural chemical called Aflatoxin - one of the most toxic and carcinogenic chemicals known.  Aflatoxin can contaminate a wide range of foods from maize (field corn), to peanuts, to cotton seed meal, to tree nuts (almond, walnut, pecan, pistachio), to wild collected nuts (Brazil nut), to dried peppers to various spices. It can even be in chocolate! For those that live in "The Global South" (or developing world), aflatoxin is one of the leading causes of illness and death - particularly through liver cancer.  If you live in the richer parts of the world, you may never hear about this toxin. Strict regulations, combined with a suite of technologies and testing protocols, do a very good job of protecting us from this threat.  I'd like to describe them, but first I need to talk about...

The Bad Guys In This Story

This threat of contamination involves a "conspiracy" between a fungus, an insect, and the climate.  Ok, its just biology, but it is still insidious.  Insects, particularly caterpillars, damage crops by feeding on them.  Certain species and strains in the fungus, Aspergillus, are able to infect parts of plants that are damaged by the worms.  The fungus produces the toxin as a means of excluding other microbes from that damaged site.  For many crops (particularly maize,) drought or heat stress increases the susceptibility of the plant to this sort of attack.

Navel Orange Worm Larvae in a Nut

In some crops (particularly tree nuts), the insect and the fungus strike a mutually beneficial pact.

A caterpillar called the Navel Orange Worm actually transports the Aspergillus fungus with it when it feeds on developing fruiting structures of the nut tree.  This worm has a phenomenally effective P450 enzyme that detoxifies the aflatoxin to which it is exposed so that both partners are protected in their niche by the toxin.  These are formidable foes, but fortunately not insurmountable when the following technologies are deployed.

Technology 1: Analytical Methods

A number of companies have developed various analytical tools to fit various parts of the system.  Rapid, cost-effective, and robust tests are available that can be used by non-experts to exclude contaminated loads before they enter the supply at somewhere like a grain elevator.  Very sensitive and precise tests are available to check the end product to meet even the high EU standard for nuts of 2 parts per billion aflatoxin.  The Gates foundation is funding development of very low cost tests to extend this life saving capability to the developing world.

Technology 2: Orchard Sanitation

There is an important "low tech" component to managing this threat.  In nut orchards, the Navel Orange Worm overwinters in "mummies"- the damaged and colonized fruiting structures which tend to stay attached to the tree, unlike the healthy nuts which are shaken loose during harvest.  

Mummies (dark) left from the previous season harbor the Navel Orange Worm

It is very important for the growers to remove as many of the mummies as possible from the trees and to destroy as many as possible of those that fall to the ground.  Workers walk through the orchard with long bamboo poles to knock down as many mummies as they can.  In a recent study in Pistachios, it was determined that a threshold of 0.2 mummies/acre was desirable to keep worm populations low enough.  That would mean that between 99.965% to 99.977% of the nuts and mummies need to be removed by either harvest operations or subsequent sanitation.

Technologies 3 and 4: Insecticides and Mating Disruption

For the nut crops, the best strategy (in addition to doing the orchard sanitation) is to use two, well-timed insecticide sprays along with mating disruption - essentially putting out lots of sources of the Navel Orange Worm's mating hormone so that the males get completely confused and unable to find the females.

In a large scale, three year study (see graph above I made from their published data), the combination of insecticides and mating disruption provided the best control of the worms and thus greatly reduced the introduction of the fungus.

Technology 5: Biotechnology (Marker Assisted Selection)

Marker assisted selection is essentially conventional plant breeding except that the breeder knows which specific genes are being moved around.  This is a side benefit of decades of investment in better and better laboratory tools for biotechnology (used in plant and medical technology). As an example, it has been used by Syngenta to develop more drought tolerant corn, and that will potentially lower aflatoxin levels.

Aspergillus infection of corn like this can be prevented with insect and drought resistance traits

Technology 6: Biotechnology (GMO)

There is also a GMO drought tolerant corn from Monsanto that will first enter the market in 2013, and this should also help reduce aflatoxin.  The more dramatic effects are seen with insect resistant corn lines (available from several companies).  If the worms (European Corn Borers in this case), can't feed long enough to damage the ears of corn, then the Aspergillus can't follow and produce the toxin.  This was observed quite clearly last year.

Technology 7: Biological Control

One very cool strategy developed by USDA scientists is finding strains of Aspergillus which compete well at colonizing insect damaged plant tissues, but which don't make the toxin.  These are called "atoxigenic strains", and they are introduced into the field as pellets that sporulate and allow these benign strains to find their way to the plants.  Syngenta, is now offering this product as Aflaguard.  The combination of the biocontrol agent and biotech-based insect resistance proved to be a particularly effective combination for maize in the 2012 drought.





Technology 8: Fluorescence Detection

With crops like tree nuts or peanuts, there is one more step that can be taken to deal with infections that slip through the other control measures (remember there is an almost zero tolerance for this issue). Shelled nuts are carried, one-by-one, at high speed, down a conveyer belt past a source of light that has a wavelength that will produce fluorescence at another specific wavelength if Aspergillus is present on a nut.  If that signal is picked up with detectors, a perfectly timed puff of air knocks that nut off the line.  This is why I always prefer to buy shelled nuts because they typically go through this process.  This procedure is also commonly used for peanuts going into peanut butter and other confectionary uses.

A great deal of effort goes into minimizing risks associated with aflatoxin in our food supply.  Extending these sorts of protections to the developing world is not easy, but is a much needed change.

You are welcome to comment here and/or to email me at savage.sd@gmail.com.  You can also follow me on Twitter (@grapedoc).

Almonds image from HealthAliciousNess' photostream. Pistachio mummy image and Navel Orange Worm in nut image from the University of California.  Aspergillus infected corn image from Iowa State University. Biocontrol image from USDA-ARS

The Shocking Carbon Footprint of Compost

Most people think of composting as a very "green" thing to do, but few realize that composting actually generates a significant amount of the potent greenhouse gases (GHG), methane and nitrous oxide.  Under current landfill regulations, requirements to exclude water minimizes the breakdown of organic matter and requirements to capture and burn methane mean that even that option has a better carbon footprint than composting (thanks to Fred Krieger for pointing out this advance in the landfill arena).  The even better option is anaerobic digestion which I will describe at the end of this post.

These Emissions Are Not A Scientific Surprise

To a microbiologist, it is not surprising that these gases would be generated during composting. Methane and nitrous oxide are formed by certain microbes when there is not enough oxygen available (anaerobic conditions). In the middle of a large-scale compost pile there are micro-sites without oxygen. This occurs even in a pile turned frequently for aeration. This is particularly true during the "hot" phase of the composting process which kills pathogens and weed seeds. During the period of very high oxygen demand, some parts of the pile will run short and the anaerobic organisms will make methane and nitrous oxide.

Counting the Cost of the Anti-GMO Movement

Last week, environmentalist Mark Lynas presented an articulate and painfully honest apology for his significant role in starting the anti-GMO movement in the 1990s.  He said that it was the most successful campaign in which he has ever been involved, but after finally looking into the science, he now deeply regrets what he and others accomplished.  While it is gratifying to have a figure like Lynas make such a turn-about, it does nothing to mitigate the damage of which this anti-science movement has perpetrated on humanity and the environment.  Ideally, such a dramatic reversal will induce others in the movement to rethink their positions. but this sort of openness to letting the science speak into bias is likely to be rare.

Lynas is right that anti-GMO campaigners have been extremely successful at blocking, delaying, or destroying potential crop improvements via biotechnology.  Lynas had a lot of ground to cover in his speech, so he only gave four examples of the ways that his previous movement has achieved its ends:

• In Europe, politicians influenced by the anti-GMO movement ignored the input from their own scientists to adopt hyper-precautionary and obstructive regulatory barriers to the technology. They have thus limited the ability of their own farmers to satisfy more of the substantial demand that the region puts on global food supplies.

• The European stance has greatly influenced the policies of many developing nations in Africa and Asia.  Such "rich world thinking" denies poor farmers the advances that could significantly improve their food security.  See Robert Paarlberg's excellent summary of this phenomenon in his book "Starved for Science."

• Phobia-driven (or publicity-seeking) vandalism by anti-GMO extremists has delayed or halted several crop innovations by destroying experimental field plots (e.g. Greenpeace "actions" against biotech wheat, or the destruction of a French field trial of grape rootstocks). 

• The anti-GMO movement has intensified the regulatory environment so that the cost of biotech crop development now requires the resources of a large company. This reduces the potential contributions from smaller start-ups, academics or government sponsored programs. 

Beyond what Lynas described, there are other mechanisms by which the anti-GMO movement has frustrated biotech crop progress.  The threat of controversy generated by anti-GMO campaigners leads to various forms of brand protectionism which can become a non-regulatory barrier to technology adoption:

• The threat of protests has been most effective when applied to companies with major consumer brands and enough market leverage to dictate what happens for a given crop.  The classic case of this phenomenon was how MacDonalds, in three phone calls to major frozen French fry producers, put an end to biotech potatoes in the US and Canada.  Potatoes are an extraordinarily difficult crop to improve through breeding because of their complex genetics and vegetative propagation.  Biotechnology was a promising way to deliver traits for important pest issues as well as quality and health benefits, and the major potato buyers knew it.  However; the risk from brand-damaging protests drove the decision. 

• The specter of consumer backlash (fanned by anti-science propaganda) concerned major wheat importers/millers in Europe and Japan.  Their response was to threaten to boycott all North American wheat if a single acre of commercial GMO wheat was planted.  US and Canadian growers, faced with such a significant drop in export sales, reluctantly asked Syngenta and Monsanto to halt their biotech wheat programs.   For the future the US, Canadian and Australian wheat industries have all decided to block any future blackmail threats by doing a simultaneous launch of biotech wheat when and if it becomes available.  In the mean time there has been a multi-decade delay for positive technologies for one of the most important of global food crops.

• Anti-GMO campaigning has made the entire topic of "GMOs" sufficiently toxic that the growers/marketers of many crops wish simply to avoid any impact on their crop's "brand" in the consumer market place.  This is what we are seeing today in the US/Canadian apple industry where a small, grower-based company has developed an innovative, consumer oriented trait.  The nervous industry has reacted quite negatively because of concerns about the apple "brand"  even though those biotech apples would only reach the market advertised specifically as biotech-improved.  This sort of thinking has also effectively blocked the use of biotechnology to solve problems in grapes as well as in most other fruit and vegetable crops

Opportunities Lost

There is a long and growing list of agricultural, environmental, and health improvement that "could have been" if the anti-GMO movement had not been so effective.  Some of these are only "nice to haves" like a fine wine.  Some of them are significant advances such as potatoes that ward off their major insect and virus pests.  Some of them are things like wheat which is less likely to have mycotoxin contamination.  Some of them are things that could enable poor farmers to produce more local food with less need for inputs or more resistance to environmental stresses.  

What Mark Lynas realized is that it is just as detrimental to the future of humanity to ignore the scientific consensus on crop biotechnology as it is to ignore the scientific consensus on climate change.  The fact that there are groups successfully blocking rational action on both these fronts presents a synergistically dire threat to efforts to feed humanity.

Addendum 1/7/13

In an ironic twist, today on the way into a computer store I was approached by a young, Greenpeace worker.  She asked, "Are you familiar with Greenpeace?"  I said, "Yes, I'm a serious opponent."  She said, "That probably means you won't want to sign my petition!"  I concurred and encouraged her to listen to the Mark Lynas speech which I described because she had not heard about it.  I hope she does because her sincere energy to do something good is being twisted into something seriously bad.

You are welcome to comment here and/or to email me at savage.sd@gmail.com.  To get a message about future posts follow @grapedoc on twitter.

Source of GMO Protest Image - University of Washington

What Would Be "A Food Movement Worth Of The Name?"

Back in October of 2012, author Michael Pollan wrote an opinion piece for the New York Times  in which he said the vote on California Proposition 37 would show whether or not the “Food Movement” had developed into “a movement worthy of the name.”  Proposition 37 failed for good reasons, but Pollan has raised a good question: 

What would a food movement worthy of the name look like?

Food is a tremendously important topic –necessary for survival, but critical in many other ways too.  Our diets influence our health in profound ways.  Food is also an integral component of culture, history and religion.  Food can be a source of great enjoyment and is an important medium for family and broader social interaction.  A worthy “Food Movement” focused on a topic of this importance should have at least the following positive goals:

·      The alleviation of hunger in the world.

·      Making sure that there is a safe, affordable and nutritious food supply

·      Helping people make good food choices for optimal health

·      Encouraging food production systems which are sustainable, just, and which have a minimal environmental impact

I’m sure that many who consider themselves part of the “Food Movement” aspire to these goals, but some of those who write, speak and blog for this movement tend to focus on what they are against more than what they are for.  Additionally, some writers are anti-scientific, inclined towards conspiracy-theory-thinking, and inclined to incite fear more than understanding.  

The Food Movement's Least Worthy Tendency

However, I believe that antipathy towards farmers is the least worthy characteristic of the current “Food Movement.”

If you reflect on the positive goals listed above, most are outcomes that can never be achieved without the critical contribution of those who actually produce the food.  By this I mean those that produce the 98+% of our food that does not come from small, local or organic farms.  While there are some foods for which localness is a real advantage, the fact that different foods tend to be produced in specific regions is because it makes the most sense to do so in terms of productivity, quality, and risk. Scientific and statistical evidence shows that organic is much less productive, and that it is not expanding in terms of acreage or production at least in our own country.  Organic is growing, but only in cost.

When many food movement advocates talk about farmers they tend to do so wielding epithets via terms, like “big,”  “factory”, “industrial,” “chemical,” or “corporate.”  They tend to imply negative or malicious or irresponsible motives.   Overall, they write about farmers in a way that indicates that they don’t actually know any of them.  I don’t think it is a good feature of any movement to dismiss broad groups with no real knowledge of those they are talking about.

What Modern, Large-Scale Farmers Are Really Like

I wish many of these writers could have the privilege to meet some of the farmers I have met over the years. Examples would be a grain producer in North Dakota with a 12,000-acre farm whose “office” is the kitchen table or the 5,000-acre grain grower in Kansas whose “office” was a desk in the corner of the machine shed with a brand new runt calf under a heat lamp next to it.  These are family farms operated by an individual or two brothers with maybe one hired hand and some family help at busy times of the year.  Between the economics, amazing equipment and the steady decline in the farming populations, this is modern farming, and it is just as noble an endeavor as ever before. 

I wish these writers could meet farm managers who work at multi-thousand acre vineyards or orchard companies in California that are actually “corporate farms”.   Like the grain farmers, these are all examples of technically sophisticated, business-smart, environmentally aware, generous and friendly folks who farm today.  Well under 1% of our population is directly involved in farming today.  Those who do are worthy of recognition, not demonization.

Farmers take on enormous economic risks each growing season with so many factors outside of their control (weather, commodity prices, pest outbreaks, new regulations…).   Rather than being armchair critics, it would be wise for Food Movement folks to assume that if farmers do something, there is probably a pretty good reason.  If they apply pesticides, it is because pests and their damage are real, and that failing to control them would compromise the production efficiency, quality and safety of their crop.  If farmers grow a certain crop or a biotech improved version of that crop it is because that is their most rational economic and risk/management choice.  The companies that sell seeds, equipment, chemicals or fertilizers to farmers can only do so if they create real value for their customers. Farmers are not stupid.  They only stay in business if they make good purchase decisions.   The products that famers buy support private investment in the development of better seed, better equipment and better crop protection chemicals.  There is nothing sinister about this.  It benefits farmers and thus, indirectly, all of us.

The Farmers Most Worthy of Food Movement Support

There are a great many “conventional farmers” who are on the cutting edge of environmentally friendly farming.  They use best practices like no-till farming and cover cropping to build soil quality and reduce off-site pollution. They use integrated pest management; fertilization via precision-variable-rate application for non-irrigated crops, or “spoon feeding” of nutrients via irrigation; or controlled wheel traffic (GPS and beyond) to avoid soil compaction and to reduce nitrous oxide emissions (greenhouse gas).   A “food movement worthy of the name” would be allied with this major group of progressive farmers.  Instead of railing at the farm community as a whole or at the companies that supply progressive farmers what they need, a worthy food movement might be brainstorming ways to change the farmland lease and credit systems which don’t encourage the sort of long-term thinking that is required for farming in the most sustainable fashion. 

Farmers are not the problem when it comes to important things about food or about legitimate goals of a worthy Food Movement.  Farmers are a critical part of the solution.

You are welcome to comment here and/or to write me at savage.sd@gmail.com