Monday, April 15, 2013

Birds and Bees

Earth day is fast approaching, and as it draws nearer the calls for civil action against the agricultural mega-corporation Monsanto grow louder and louder. It is a great and powerful buzzing. Like a giant hive of bees.

Bees are in fact a significant prop in this anti-Monsanto play.

Industrial agriculture has a long history of causing significant environmental damage.Rachel Carson's 1962  book “Silent Spring” helped to popularize the very idea of environmental damage with the story of how the organochlorine insecticide dichlorodiphenyltrichloroethane (DDT) might be causing damage to the ecosphere.

DDE is the toxic breakdown product of DDT that can be found in animal tissue. DDE is perhaps the most famous marker of food chain magnification of a toxic material. Since banning  of DDT others, like mercury and PCBs, have become famous as well.  Though DDT is not extremely toxic to vertebrates at the levels it was applied to crops DDE concentration would be magnified by food chain accumulation till high-level predators might have thousands of times the concentration initially applied to crops for insect control.

DDE was especially damaging to birds as at high enough concentrations it inhibits a key enzyme in eggshell formation.

The class of insecticides known as neonicotinoids made by Bayer are implicated as one of the factors that is applying stress to bees. These nicotine-related insecticides apparently do not magnify in the food chain like DDT/DDE.  The use of the neonicotinoid insecticides adds to the combined stresses on modern beehives which together are thought to be causing significant numbers of hive deaths; including those attributed to colony collapse disorder.

I know that I've not made a connection between Monsanto and the bees, but this is the road one must go down to understand where the connection comes from.

What Monsanto has done is successfully market genetically modified crops (GMO) for food use.

The very idea of GMOs offends the strongly held religious beliefs of many people. Man should not “play god” by creating “Frankenfoods”. Many people believe that tampering with the genetic code in a living organism is tampering with some divine plan, and it invites some unspecified divine retribution. The battle against GMOs has taken on the flavor of a jihad.

I personally think that the application of techniques for genetically modifying crop plants will result in wonderful foodstuffs for future consumption. I can imagine a wonderful world with decreased chemical contamination, and increased variety and flavor. Because of these utopian fantasies I have been branded a “Frankenfooder”. It sounds like an evil label.

Should I be worried that farmers armed with pitchforks and torches will storm my garden and mistakenly destroy my heirloom tomatoes? If they want to be effective they will have to get to them before the deer eat them,

Unfortunately the first few large-scale GMOs are not what I would have chosen. Though I like the idea that GMO processes can bring products from the laboratory to the table I think they could have chosen much more wisely.

The roundup ready soybeans were the first plants I noticed hitting the market. In order for this genetic modification to be useful the farmer has to also be ready to use roundup, and then he has to apply a bunch of it. The active ingredient in roundup is the enzyme inhibitor glyphosate (N-(phosphonomethyl)glycine). The genetic modification is the insertion of an enzyme that is resistant to glyphosate inhibition. The gene comes from a common soil bacterium

Inseertion of a bacterial gene is not the only way to combat glyphosate inhibition. I would assume there are all sorts of mutations in either the susceptible enzyme or the physiological processing of  glyphosate that can result in resistance. If I was to design a large-scale experiment to discover some new ways of relizing glyphosate resistance I would simply apply large quantities regularly to a large variety of weeds, and see what grew. This is in essence what growing roundup ready soybeans does. Unfortunately the farmer growing roundup ready soybeans cannot afford to simply collect some roundup resistant weeds, and declare a success. The farmer must apply more and larger quantities of roundup in the hopes of achieving a concentration that is just enough to kill off the resistant weeds, but not enough to kill off the soybeans. Natural selection at work.

The other GMO that I think is a mistake is MON810. MON810 is a corn transformed with Bacillus thuringensis toxin (BtT). BtT is a protein insecticide that specifically targets certain types of insects. It is extremely effective against lepidopterans (butterflies and moths)

I don't have the same problem with BtT transformed corn that I have with Roundup-ready soybeans, but natural selection is still the complicating factor in the use of this product.

In the typical soil of a farm one might expect to find several strains of crystal-protein producing Bacillus. It would be surprising to not find a BtT. Many farms use BtT as an effective organic insecticide. Some produce can apparently be labeled organic is only BtT is used as an insecticide on it. BtT can be aerially sprayed on people's homes. It has been repeatedly sprayed on several Washington Dc suburbs to control Gypsy Moth infestations; I bet there are several Monsanto lobbyists in those high-dollar neighborhoods. However, in all these cases the BtT is not chronically present in the environment in high enough concentrations to provide a constant selective pressure.

Unlike DDT BtT is a protein and its breakdown products are amino acids, and neither it nor its breakdown products bio-accumulate as toxic materials in the food-chain.

In the fields around a field of BtT GMO corn insects will come into contact with sub-lethal amounts of BtT. After the corn is harvested, and the stalks are plowed into the soil insects there will be exposed to sub-lethal concentrations of BtT.

Closer to the field of GMO corn, and perhaps near the roots in the soil around them insects will be exposed to lethal but sub-optimal concentrations of BtT.

This gradient of BtT will persist as long as the crop does; likely through generations of insects. This sets up a situation where, even in the absence of outright resistant insects to be selected for, BtT resistance will provide a clear selective advantage. Since insects can have thousands of offspring the ability for just a couple of resistant individuals to graze several acres of land made unsuitable to their closest competitors can result in huge numbers of resistant progeny in one generation. The synergies of partial and co-dominance could result in even more resistance in subsequent early generations.  The risk of resistance to BtT is very real.

BtT is a wonderful product. It is used for all sorts of things. The one used in MON810 is so very specific to lepidopterans that beekeepers can spray their bees directly with it to eradicate wax moths.

Unfortunately my objections to the current crop of GMOs involves invoking natural selection, which is an anathema to many people who religiously object to GMOs. It also does not paint the process of developing GMOs as evil, only the examples of having done it. For that reason these -I think reasonable- objections are not often given voice by those objecting to GMOs.

This is how the anti-GMO folks I know and I can effectively agree on controlling the use of current GMOs, and yet they can malign my position and label me a “Frankenfooder”. The fight against Monsanto apparently also resembles a religious movement in that purity of thought is highly valued.

So the relationship between Monsanto and bees is that Monsanto made MON810 which has an insecticide in it, and there is another group of insecticides made by another company which may be causing significant damage to beehives. To me this is not a very satisfying connection, but to many in the anti-GMO movement is is sufficient. Not a week goes by that I am not offered an article to read that implies a relationship, and simply refuses to point out that one does not exist.

I should point out that the lack of lethality of BtT toxins on bees is not simply inferred from lack of evidence. It is also not simply inferred from the fact that many beekeepers have for decades regularly applied large concentrations of BtT directly to their beehives with no deleterious effects. I infer it from controlled scientific experiments published in peer-reviewed literature.

Several European countries have apparently banned planting of MON810, and at least one has specifically cited protecting bees as the reason. In Poland protestors dumped about a hive of dead bees and a painted sculpture of a human skull on the steps of their Ministry of Agriculture. When the Polish minister of agriculture announced the MON810 ban he apparently mentioned the need to safeguard bees. He also apparently mentioned that MON810 had already produced millions of hectares of pesticide resistant “superweeds” in the US. The later is interesting because it not only does make use of the natural selection concerns it confuses the genetic modification in the MON810 with that in the roundup-ready soybeans.

Several of the articles mention work done by a bee researcher that linked MON810 to colony collapse disorder. The bee researcher's name was John McDonald who turns out to be a blogger-beekeeper from Pennsylvania whose haphazard experiments have earned him a byline in publications originating as far away as San Francisco.

John did run a couple of experiments where he put hives in interesting places, and then weighed them. Unfortunately the level of resolution he exercised in his control over the hives does not allow one to point to any particular cause for the difference between his strategically placed hives. If one interprets his results in light of the controlled laboratory experiments it appears as if something other than casual exposure to some MON810 pollen was the more likely cause of his problems.

John recognizes the limitations of his experiments, but instead of using Occam's razor to interpret them in the simplest way he imagines hidden effects appearing just bellow the surface of his results. Such speculation is actually fine for stimulating interest and investigation, but it does not rise to the level of actionable information that should inform policy.

“Is it not possible that while there is no lethal effect directly to the new bees, there might be some sublethal effect, such as immune suppression, acting as a slow killer? “ – John McDonald

Of course, as I mentioned earlier, I'm not opposed at all to restrictions on the use of these Monsanto GMOs. I just wish the road to deciding to restrict them was not so logically bumpy.

The most problematic fallout from this crusade might be the elimination of neonicotinoids. Without them what will farmers use? Will they go back to the organophosophates and carbamate insecticides they partially replaced? Neonicotinoids may be highly toxic to bees (bees are insects), but the organophosophates and carbamate insecticides are both highly toxic to bees, and humans...and all sorts of living things.

VX nerve gas, amongst the scariest of the weapons of mass destruction, is an organophosphate compound similar to the insecticides.

On the 2nd of December 1984 a plant making precursors for carbamate insecticides in Bhopol india had a leak which killed as many as 16,000 people (why are there not good numbers for things like this?), and injured over 500,000 others.

Of course it may not be a question of returning to using poison on our food in order to ban neonicotinoids so we can halt GMOs. We may all start sustaining ourselves with organically grown heirloom tomatoes, and fat-marbled suburban venison.

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