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A Different Kind of Mushroom Cloud: Fighting the Drug War With Killer Fungi

Whether you support it or not, there's no denying that the War on Drugs has been absurdly costly. With people freaking out over budget minutiae and border cities like Ciudad Juarez looking like straight-up war zones (and, with heads being rolled around...

Whether you support it or not, there’s no denying that the War on Drugs has been absurdly costly. With people freaking out over budget minutiae and border cities like Ciudad Juarez looking like straight-up war zones (and, with heads being rolled around, possibly worse), politicians are in a tough spot. To give up the drug war means both admitting defeat and, in the eyes of some of their constituents, basically legalizing drugs. To continue down the road we’re on means continuing to commit billions of dollars to trying to at least stem the flow of narcotics into and around the U.S.

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The government is thus scrambling for a third option. Of particular interest is attacking the drug industry at its source. But how does one effectively, discretely and accurately eradicate plants that can grow anywhere without destroying their surrounding ecosystems? It’s not like we can go out and carpet bomb all of Colombia’s farms and forests. Instead, the architects of the drug war are looking at a more scalpel-like option: Engineering custom fungi to wage a biowar on drug-producing plants.

Attacking the drug trade at the source means dealing with a highly-militarized industry, making manpower-intensive operations like raids fairly ineffectual on a grand scale.

The Committee on Mycoherbicides for Eradicating Illicit Drug Crops, a subset of the National Research Council formed at the direction of the Office of National Drug Control Policy and Congress, just released an exhaustive 168-page study looking at the potential for using fungi as targeted herbicides to destroy drugs before their parent plants mature.

This Colombian cropduster helps give you an idea of what the plan for mycoherbicide use would likely be: spray killer fungi all over the forest, and hope it just focuses on the drugs.

It sounds like a bioengineered dream: With the support of local governments (or perhaps not), we could disperse custom fungal spores designed specifically to target and wreck drug crops. Ideally, such a solution wouldn’t affect any other plants or animals. Also, being alive, it could self-propagate, spreading to whatever specific plants are available and dying off when all the coca or cannabis plants it feeds on are dead.

Indeed, the committee already found one candidate to take out coca and cannibis: Fusarium oxysporum, a species complex that is "pathogenic to a wide variety of plant species, including several economically important vegetable and ornamental crops." A number of individual species within that group attack both coca and cannabis specifically, and research into their use as biological control agents dates back at far as the Seventies.

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Fungi are already known to attack cannabis, coca and opium poppies, as evidenced by this moldy weed. But the use of mycoherbicides means using targeted fungal strains that, without the normal natural checks and balances, may overpower the delicate balance of a particular ecosystem.

Fusarium is a valuable candidate because some species solely reproduce asexually, which helps eliminate the rise of messy recombinants whose tastes shift from, say, weed to our all-important corn crops. And that’s the end goal: to find a specific strain of Fusarium that attacks just drug plants, and which won’t change over time to end up destroying other crops as well. The target fungi species must also act quickly and kill effectively, although "eradication of the crops is not a realistic goal, because biological agents rarely, if ever, kill 100 percent of their hosts."

The committee also found two genera of fungi that showed potential in controlling opium poppy crops. Crivellia and Brachycladium fungi are both well-documented pathogens of opium poppies. As noted in the report, researchers in Uzbekistan found in 1991 a "highly virulent" species of Crivellia that attacks poppy plants. It’s lethality was ideal, with researchers finding it "caused 50-75 percent losses in licit and illicit poppy crops." Collateral damage was unmentioned: researchers "did not specify under what environmental conditions the losses occurred."

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Here’s Crivellia. This little guy loves eating opium poppies.

And therein lies the problem. Finding fungi with a high enough lethality to use as mycoherbicides is a matter of research and potential fine tuning in the lab. The mycoherbicide concept is thus feasible. But how risky is it to use biological controls, something humans have never been particularly successful with, to fight the drug war?

The simple answer is that no one really knows how risky such an operation would be. With regard to whether the mycoherbicides could affect biodiversity, adversely affect ecosystems or pose health risks to humans and animals, the authors state that there is little to no reliable data. When it comes to releasing living, replicating herbicides into the environment, we simply don’t know what will happen. We do know, however, that once they’re out, they’re out. As the authors write:

Control or containment of the mycoherbicide strains after they are released would be all but impossible. The fungal strains are living organisms that interact with and adapt to their environment. Their ability to survive, propagate, and disperse beyond the target area would depend on environmental factors that can be neither predicted nor controlled.

With that in mind, the study concludes with a caveat: While the idea seems both feasible and potentially cost-effective, an enormous amount of research needs to be done. First, potential mycoherbicides must be thoroughly tested in both controlled environments and target locations to try to get an idea of the fungi’s ability to persist and their affect on local biodiversity. Secondly, and more importantly, species picked for potential use must be studied in terms of their mutative abilities; the risk that a mycoherbicide released to the wild mutates to a form that attacks native plants or valuable crops is real and potentially devastating.

But the end result is this: The government is looking hard at using fungi in the drug war, and this major study suggests it’s possible, assuming a vast quantity of further research is carried out. The question now, if interest in mycoherbicides persists, is whether or not that homework is actually going to get done.

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