Backpackers, Don’t Listen To Slate: Science Does Support Stream Water Treatment

The risk might be low, but the alternative is maybe months of debilitating diarrhea. It's your choice. Photo Credit: Timothy Epp/Shutterstock
The risk might be low, but the alternative is maybe months of debilitating diarrhea. It’s your choice. Photo Credit: Timothy Epp/Shutterstock

While we like to think of ourselves as rational creatures, there’s no doubt that human beings are actually quite awful at assessing risk. So I can understand why Ethan Linck thought to contextualize the risk of drinking from backcountry streams with data. “Life is triage, a constant series of negotiations between risks of varying severity,” he wrote. “And how we talk about those risks matters.”

Yes, it does—which is exactly why his piece in Slate last week was so damaging. It was anything but a careful, scientific evaluation of the risks. Wes Siler over at Outside Magazine already pointed out a myriad of issues with the article, but I want to zero in on the actual data, because Linck claimed to be looking at the matter scientifically. Instead, he cherry-picked sources to argue against doing one of the simplest things you can do to protect yourself from some truly awful diseases when you’re backpacking: treating your water. Continue reading “Backpackers, Don’t Listen To Slate: Science Does Support Stream Water Treatment”

Mythbusting 101: bulking up with bull shark testosterone

This week, the startling image of a 1,000 pound bull shark has been circulating the internets. But what really caught my eye was the quote from the lead researcher. He told news outlets that bull sharks “have the most testosterone of any animal on the planet, so that should tell you a little something.” Tsk tsk. No matter what those websites tell you, it’s simply not true.

This isn’t the first time I have heard this whole bull sharks and testosterone bit. Indeed, all over the internet, you see claims that bull sharks are so aggressive because of their insane testosterone levels. But it was the character Bruce Kibbutz in Grand Theft Auto IV that really got people talking about bull shark testosterone. During the game, the roid-raging fitness freak explains how he juices on testosterone taken from Chilean bull sharks. Suddenly, extreme body builders and skeptics wanted to know if you could really bulk up on bull shark blood.

The rumor, as I’d heard it in college, is that the fierce attitudes of these large and aggressive sharks is due to unfathomably high circulating levels of testosterone. Specifically, these menacing monsters supposedly have higher serum testosterone levels than any species on the planet, land or sea, and that even a female bull shark has higher levels than a testosterone-raged male elephant in musth. I know I’m as much to blame as anyone, as I’ve repeated that line myself. But when I was asked about it, I realized that I didn’t know if it’s true. How do the circulating testosterone levels compare between bull sharks and other species? Could you procure enough testosterone by catching and eating bull sharks to beef up your body?

Let’s start with that elephant. In the red corner, standing up to 11.5 feet tall and weighing in at up to 20,000 lbs, we have the African Bush Elephant (Loxodonta africana). What’s the testosterone level in this whomping beast? During much of the year, not much. Male elephants, on average, have less than 2 ng/ml ciculating in their plasma. But wait! Big boy wants to get his groove on, and he is getting ready for a season of fighting and fornicating. So what’s the male elephant in musth’s testosterone level? As high as 64.4 ng/ml! About a 60 fold increase in average circulating testosterone1. Ai! That’s a lot of anger-pumping hormone.

How about his opponent, the every day female bull shark (Carcharhinus leucas)? In the blue corner, weighing in at around 505 lbs and stretching almost 12 feet long, is our large and in charge girl. She’s bigger than her man, no doubt, but she still has to keep her femininity about her. After all, as a girl, if her testosterone levels are too high, she might have reproductive issues. Surely her circulating levels are lower than the male elephant’s?

According to the only, extremely obscure published reference with testosterone levels in a female bull shark, actually, yes, they are2. Her circulating testosterone level is right around 0.1 ng/ml, a whole lot lower than that angry elephant. Sorry to burst bubbles, but she ain’t gonna give anyone roid rage. Her man, though… My oh my. One of the two male adult bull sharks in that study had a circulating testosterone level of 358 ng/ml. Yeah, that’s one roided out shark. Problem is, the other male bull shark in that study only had 2.7 ng/ml of testosterone in his serum – which is probably less than you male readers out there have pumping in your blood right now. So not all male bull sharks are running around roided out of their minds. To be fair, these were just single sharks, caught once and tested once. Without a more complete study of the average hormone levels in bull sharks, by size, season, etc, we can’t really say that bull sharks have abnormally high or low testosterone levels.

Of course, there is a more complete study. Not a super detailed one, but a study none the less. Rasmussen & Murru3 studied androgen levels in a number of captive sharks over time. They found testosterone levels of 10 ng/ml to 20 ng/ml in two captive bull sharks when they measured every June for three years, just after the sharks’ normal breeding season. Not too impressive, boys – not too impressive, but of course, that is in captivity, and it’s unknown how captivity may affect their hormone levels.

In wild bull sharks caught right before the breeding season, the serum levels were much higher: 185 ng/ml on average – which was 4 to 10 times higher than the levels they found in two other shark species, and is pretty impressive compared to the elephant. But, it turns out, it’s not that hard to find high testosterone levels in fish. Other sharks have high levels, too – like the bonnethead, Sphyrna tiburo, whose highest levels have been recorded at 303 ng/ml4. And in that species, even the girls have higher levels than our elephant – a whopping 74 ng/ml at max5. Believe me, I’d rather go hunting bonnethead than bull sharks any day. Other fish, too, have been found to have high testosterone. Male rainbow trout have levels around the same as those of the bonnetheads6, and heck, they sound a whole lot tastier to me than the other options. Just sayin’. Sorry folks, but according to the best, albeit limited scientific information we have, the idea that bull sharks are super juiced-up compared to other animals just isn’t true.

Yet in the news and even on the Discovery Channel’s infamous Shark Week, the highest-testosterone-in-the-world bull shark is the norm. How did the data end up so skewed towards this single result? As I see it, it is the scientific community that is to blame for the impression that bull sharks are testosterone-pumped. Every other paper I read about shark hormones since the two with bull sharks cites them, specifically mentioning 358 ng/ml and that bull sharks have much higher levels than other sharks.

Now that I read the papers, I see it’s not the media’s fault. It’s the original authors that claim that bull sharks have higher testosterone than other sharks, even without presenting evidence to back it up. It started with how Rasmussen & Gruber were quick to point out how high that 358 ng/ml value is, saying it’s “among the highest recorded in vertebrate serum,” but didn’t talk at all about why the other mature male bull shark (by their own identification) was more than one hundred fold lower. But it’s really Rasmussen & Murru (hmm… that first name sounds familiar), in their discussion, who seem to overinflate their own data. They state that “a species differences in absolute concentrations appears to exist because concentrations of testosterone in both wild and captive bull sharks were about two times higher than those in mature sandbar and lemon sharks” (emphasis mine). Yet their included figure showing the yearly serum concentrations for the two captive bull sharks studied clearly shows the levels between 5 ng/ml and 20 ng/ml, while the levels for the two captive sandbar sharks sampled at the same and different times of year range from 0 ng/ml to over 40 ng/ml! Two to four times higher in bull sharks? Where? When?!

But enough griping about inaccurate inflation of results. Let’s say, for a hypothetical moment, that there is a time of year, size, or whatever where you could go out with a shark hook and some dead fish and guarantee getting a big boy bull shark with upwards of 300 ng/ml in his system. It’s time to address the other part of the myth: Should serious users think about going fishing?

You’ll have one big fish to fry if you’re trying to get a nice dose of testosterone by ingesting sea creatures. First off, I hope you’re feeling vampiric. You want the blood, not the tissues. We don’t know anything about how much testosterone is in bull shark tissues, and besides, that super high amount was in the blood… so, yeah. Cheers. Second off, unless you’re planning on shooting up shark blood, you’re not getting the dose you think. Orally ingested testosterone is rapidly absorbed by the gut, but it’s also converted to inactive metabolites, leaving you with only 1/6th the dose you took remaining in active form. That’s why pills and injections aren’t actually of straight testosterone, they’re of slightly modified chemicals that the body doesn’t metabolize as easily. It also means that to get the same dose from shark as you would from a prescription (or black market) pill, you have to drink six times what you think you have to.

So let’s say you want to replace that 40 mg pill you bought with bull shark blood. Even if you catch that one shark that had 350 ng/ml in his serum, that means you’ll have to drink down three cups of shark plasma to equal one pill. A shark tends to be about 12.3% blood by weight according to previous studies7 – that’s 6.8% blood cells and 5.5% serum, which has a specific gravity (weight per volume) of around 1.03. So say you caught an average bull shark, weighing only 350 lbs instead of the max of 500. He’ll have around 44 cups of blood in him, which is only 44% plasma, so you’ll need to drink 6.8 cups of blood per pill. So at 2-5 pills a day, that shark will only last you one to three days. Hey – I guess it’s legal. Though somehow, I don’t think athletes are going to get away with the old “I was just drinking shark blood” excuse just because of that.

Of course, all of that assumes that the majority of bull sharks are swimming around with high testosterone levels, which as the data reveals, simply isn’t likely. What’s worse, though, is that by perpetuating the idea of roided-out sharks, we’re giving credence to the idea that bull sharks are mindless killing machines with a taste for blood. While bull sharks are certainly dangerous animals, they are far from the angry maneaters they’re portrayed to be. Given that you’re still more likely to die from being struck by lightning that by a shark attack, and that there are probably hundreds of thousands of bull sharks in the Atlantic Ocean alone… I’d say the bull sharks are being pretty restrained.

 

Citations: 1. JAINUDEEN, M., KATONGOLE, C., & SHORT, R. (1972). PLASMA TESTOSTERONE LEVELS IN RELATION TO MUSTH AND SEXUAL ACTIVITY IN THE MALE ASIATIC ELEPHANT, ELEPHAS MAXIMUS Reproduction, 29 (1), 99-103 DOI: 10.1530/jrf.0.0290099

2. Harold L. Pratt, Jr., Samuel H. Gruber, & Toru Taniuchi (editors) (1990). Elasmobranchs as Living Resources: Advances in the Biology, Ecology, Systematics, and the Status of the Fisheries NOAA Technical Report NMFS 90, 143-155

3. Rasmussen, L., & Murru, F. (1992). Long-term studies of Serum Concentrations of reproductively related Steriod Hormones in individual captive Carcharhinids Marine and Freshwater Research, 43 (1) DOI: 10.1071/MF9920273

4. Manire, C. (1997). Serum Concentrations of Steroid Hormones in the Mature Male Bonnethead Shark,Sphyrna tiburo General and Comparative Endocrinology, 107 (3), 414-420 DOI: 10.1006/gcen.1997.6937

5. Manire, C. (1995). Serum Steroid Hormones and the Reproductive Cycle of the Female Bonnethead Shark, Sphyrna tiburo General and Comparative Endocrinology, 97 (3), 366-376 DOI: 10.1006/gcen.1995.1036

6. Scott, A. P., & Baynes, S. M. (1982). Plasma levels of sex steroids in relation to ovulation and spermiation in rainbow trout (Salmo gairdneri) Proc. Int. Symp. Reprod. Physiol. Fish, 103-106

7. Thorson, T. (1962). Partitioning of Body Fluids in the Lake Nicaragua Shark and Three Marine Sharks Science, 138 (3541), 688-690 DOI: 10.1126/science.138.3541.688

Note: this post is updated from a version posted on Science Blogs in 2010

Mythbusting 101: Sharks will cure cancer

Tiger Shark at Coconut Island
Tiger Shark at Coconut Island

Sharks are incredible animals. They’re some of the world’s most well known creatures, popular enough to get entire weeks of television dedicated to them. They hold a special place in our hearts and minds. Whether you fear them or love them, or a bit of both, they’ve dominated our oceans for hundreds of millions of years, and still manage to evoke powerful emotions from us.

But, as amazing as they are, they are not going to cure cancer.

First off, there will never be a “cure for cancer”. Not now, not in 50 years, no matter how much we know about how cancers form and spread. And no, it won’t be because there is some big conspiracy, where doctors and pharmaceutical companies are keeping some miracle drug from hitting the market.

You see, there can’t be a cure for cancer, because cancer isn’t a single disease. Cancer is a category of diseases, like rock is a category of music. While rock music is characterized by being song-based, usually with a 4/4 beat and a verse-chorus form, cancer is characterized by cell growth gone terribly wrong, allowing a group of cells to grow uncontrollably. You wouldn’t say that Korn and Elvis sound the same, would you? Well not all cancers are the same, either. Some cancers are slow growing, some are fast. Some are always fatal, others go away on their own.

The thing is, there is no universal trait to all cancers that can be attacked with one treatment, except for the fact that they are cells that grow out of control. Thus a universal cure for cancer would have to be something that prevented and reversed cell growth, which will never, ever be safe to take over an extended period of time. You need cells to grow and replicate in your body – just not when and where they shouldn’t be.

The treatment for a given cancer is heavily dependent on where it is and what it’s doing. There may eventually be a million cures – a cure for Acute Lymphoblastic Leukemia, a cure for Basal Cell Carcinoma, a cure for Craniopharyngioma, and so on and so forth from A to Z – but there will never, ever be a cure for cancer.

But I digress.

The notion that sharks may hold they key to curing cancer rests on the idea that sharks don’t get cancer. Out of all they myths in the world, there are few that have been more ecologically damaging and pervasive despite unequivocal scientific evidence to the contrary. This simply untrue statement has led to the slaughter of millions of sharks via the industry for shark cartilage pills, which are sold to desperate cancer patients under the false pretense that they can help reduce or cure their illness.

The myth started way back in the 1970s when Henry Brem and Judah Folkman from the Johns Hopkins School of Medicine first noted that cartilage prevented the growth of new blood vessels into tissues. This creation of a blood supply, called angiogenesis, is one of the key characteristics of malignant tumors, as the rapidly dividing cells need lots of nutrients to continue growing. It’s not shocking, then, that angiogenesis is a common target for those seeking potential cancer therapies.

Brem and Folkman began studying cartilage to search for anti-angiogenic compounds. They reasoned that since all cartilage lacks blood vessels, it must contain some signaling molecules or enzymes that prevent capillaries from forming. They found that inserting cartilage from baby rabbits alongside tumors in experimental animals completely prevented the tumors from growing1. Further research showed calf cartilage, too, had anti-angiogenic properties2. A young researcher by the name of Robert Langer decided to repeat the initial rabbit cartilage experiments, except this time using shark cartilage. Since sharks’ skeletons are entirely composed of cartilage, Langer reasoned that they would be a far more accessible source for potential therapeutics. And indeed, shark cartilage, like calf and rabbit cartilage, inhibited blood vessels from growing toward tumors 3.

Around the same time, a scientist by the name of Carl Luer at Mote Marine Laboratories in Sarasota, FL was looking into sharks and cancer, too. He’d noticed that sharks seem to have relatively low rates of disease, especially cancer, and wanted to test their susceptibility experimentally. So he exposed nurse sharks to high levels of aflatoxin B1, a known carcinogen, and found no evidence that they developed tumors4.

That’s when Dr. I William Lane stepped in. He’d heard about the studies done by Langer and Luer, and become immediately entrenched in the idea that oral shark cartilage could be a treatment for cancer. In 1992 he published the book Sharks Don’t Get Cancer: How Shark Cartilage Could Save Your Life. The book was a best-seller, popular enough to draw in the media from 60 Minutes who did a special on Lane and his new cancer cure. The segment featured Lane and Cuban physicians and patients who had participated in a non-randomized and shoddily done ‘clinical trial’ in Mexico which heralded spectacular results. He then co-authored a second book, Sharks Still Don’t Get Cancer, in 1996.

Of course, Lane started up his own shark fishing and cartilage pill making business called LaneLabs (which still made and sold cartilage pills until recently). But Lane was not alone – many companies began selling shark cartilage pills and powders as alternative therapies or nutritional supplements. The world market for shark cartilage products was estimated to have exceeded $30 million in 1995, prompting more and more harvesting of sharks for their cartilage.

The results have been devastating. North American populations of sharks have  decreased by up to 80% in the past decade, as cartilage companies harvest up to 200,000 sharks every month in US waters to create their products. One American-owned shark cartilage plant in Costa Rica is estimated to destroy 2.8 million sharks per year5. Sharks are slow growing species, and simply cannot reproduce fast enough to survive such sustained, intense fishing pressure. Unless fishing is dramatically decreased worldwide, a number of species of sharks will go extinct before we even notice.

It’s bad enough that all this ecological devastation is for a pill that doesn’t even work. Shark cartilage does not cure or treat cancer in any way, even in mouse models6. These are also the results of at least three randomized, FDA-approved clinical trials – one in 19987, another in 20058, and a final one presented in 2007 (published in 2010)9. Ingestion of shark cartilage powders or extracts had absolutely no positive effects on cancers that varied in type and severity. To paraphrase Dr. Andrew Vickers, shark cartilage as a cancer cure isn’t untested or unproven, it’s disproven10. Indeed, the Federal Trade Commission stepped in by 2000, fining Lane $1 million as well as banning him from claiming that his supplements, or any shark cartilage derivatives, could prevent, treat or cure cancer.

But what’s worse is that this entire fraudulent enterprise that steals the money of those desperate for any kind of hope is based on a myth. No matter what a money-grubbing man with a PhD in Agricultural Biochemistry and Nutrition tries to tell you, sharks do get cancer.

Shark Tumors
L: Kidney Tumor, R: Cartilage Tumor

In 2004, Dr Gary Ostrander and his colleagues from the University of Hawaii published a survey of the Registry for Tumors in Lower Animals11. Already in collection, they found 42 tumors in Chondrichthyes species (the class of cartilaginous fish that includes sharks, skates and rays). These included at least 12 malignant tumors and tumors throughout the body. Two sharks had multiple tumors, suggesting they were genetically susceptible or exposed to extremely high levels of carcinogens. There were even tumors found in shark cartilage! Ostrander hoped that this information would finally put to rest the myth that sharks are somehow magically cancer-free.

But it hasn’t. I still see all kinds of shark cartilage pills for sale at the local GNC. But furthermore, the myth that sharks are cancer-free is still believed by many intelligent people. I read a tweet from The National Aquarium a while ago that said “It must be something in the water. Sharks are the only known species to never suffer from cancer.” The National Aquarium has over 9,000 twitter followers, and this inaccurate tweet was passed on by a number of them, including The Smithsonian Marine Station in Fort Pierce, FL. How can such a large non-profit, dedicated to “extending the knowledge and resources gained through daily operations toward the betterment of the natural environment” perpetuate such an erroneous and ecologically damaging myth?

Then there’s the BBC, whose division called BBC Earth decided to run a “trick or treat” campaign for Halloween last year featuring truths or falsehoods about different animals. Among them?

Trick or Treat? Sharks don't get cancer

When I called them out on their egregious error, they didn’t even admit they were wrong. Instead they simply said that “the science behind their immune systems is still an area of fascination which we know little about, and thankfully people are still studying.”

Maybe I haven’t been clear. Maybe we don’t know everything about shark immune systems, but there is one thing that we do know with 100% certainty.

SHARKS DO GET CANCER.

We can’t even really say they get cancer less often than other species. It’s true that the number of sharks that we have observed with cancer is low. However, only a couple studies have even attempted to look at disease rates in shark species. Furthermore, these studies are hampered by the fact that sharks tend to be wide-ranging, open ocean fish. They live in some of the least contaminated areas on earth. This means that, odds are, they have low levels of exposure to the chemicals that cause cancer in so many land and near-shore species. Furthermore, the odds that a really sick shark would make it into a researcher’s hands to study are slim. A shark whose function is compromised by tumors would likely end up the meal of other, hungry sharks long before they’d end up on a hook cast by scientists. So even the idea that sharks have low rates of cancer or disease is hard to scientifically support.

Perhaps the most disappointing part is that the shark immune system is incredibly fascinating and worth study whether or not it can squash out cancer. Sharks are the earliest evolutionary lineage to have developed an adaptive immune system complete with immunoglobin, T-cell receptors, MHCs and RAG proteins12, and they do it without bone marrow, the source of almost all of our immune system cells. Instead, they have two completely unique immune organs, the Leydig’s and Epigonal organs, that are barely understood. Studying the shark immune system is essential to understanding the evolution of adaptive immunity that is present in all higher vertebrates. And if, indeed, they are resistant to cancer, then that makes the study of their immune system all that much more important.

Carcasses of sharks fished for their fins

Instead, we mindlessly kill millions of them a year to make Asian delicacies and ineffective cancer treatments, and we perpetuate the myth that sharks don’t get cancer. Be assured that whenever I see someone say that sharks don’t get cancer, I will call them out, especially if they should know better. It’s time that this myth is busted once and for all.

 

Images: A 5′ tiger shark at Coconut Island, photo © Christie Wilcox; LaneLabs Shark Cartilage Powder; Tumor examples from Ostrander et al. 2004. Left: a shark kidney tumor, right: a tumor in shark cartilage; Sharks at a factory finning plant in Japan, photo © Alex Hofford

References

  1. Brem H, & Folkman J. (1975). Inhibition of tumor angiogenesis mediated by cartilage. J Exp Med (141), 427-439 DOI: 10.1084/jem.141.2.427
  2. Langer R, & et al (1976). Isolations of a cartilage factor that inhibits tumor neovascularization. Science (193), 70-72 DOI: 10.1126/science.935859
  3. Lee A, & Langer R. (1983). Shark cartilage contains inhibitors of tumor angiogenesis. Science (221), 1185-1187 DOI: 10.1126/science.6193581
  4. Luer CA, & Luer WH (1982). Acute and chronic exposure of nurse sharks to aflatoxin B1 Federal Proceedings, 41
  5. Camhi M. Costa Rica’s Shark Fishery and Cartilage Industry. http://www.flmnh.ufl.edu/fish/Organizations/SSG/sharknews/sn8/shark8news9.htm (1996).
  6. Horsman MR, Alsner J, & Overgaard J (1998). The effect of shark cartilage extracts on the growth and metastatic spread of the SCCVII carcinoma. Acta oncologica (Stockholm, Sweden), 37 (5), 441-5 PMID: 9831372
  7. Miller DR, Anderson GT, Stark JJ, Granick JL, & Richardson D (1998). Phase I/II trial of the safety and efficacy of shark cartilage in the treatment of advanced cancer. Journal of clinical oncology : official journal of the American Society of Clinical Oncology, 16 (11), 3649-55 PMID: 9817287
  8. Loprinzi CL, Levitt R, Barton DL, Sloan JA, Atherton PJ, Smith DJ, Dakhil SR, Moore DF Jr, Krook JE, Rowland KM Jr, Mazurczak MA, Berg AR, Kim GP, & North Central Cancer Treatment Group (2005). Evaluation of shark cartilage in patients with advanced cancer: a North Central Cancer Treatment Group trial. Cancer, 104 (1), 176-82 PMID: 15912493
  9. Lu C, Lee JJ, Komaki R, Herbst RS, Feng L, Evans WK, Choy H, Desjardins P, Esparaz BT, Truong MT, Saxman S, Kelaghan J, Bleyer A, & Fisch MJ (2010). Chemoradiotherapy with or without AE-941 in stage III non-small cell lung cancer: a randomized phase III trial. Journal of the National Cancer Institute, 102 (12), 859-65 PMID: 20505152
  10. Vickers, A (2004). Alternative cancer cures: “unproven” or “disproven”? CA: A Cancer Journal For Clinicians, 54, 110-118 DOI: 10.3322/canjclin.54.2.110
  11. Ostrander GK, Cheng KC, Wolf JC, & Wolfe MJ (2004). Shark cartilage, cancer and the growing threat of pseudoscience. Cancer research, 64 (23), 8485-91 PMID: 15574750
  12. Flajnik MF, & Rumfelt LL (2000). The immune system of cartilaginous fish. Curr Top Microbiol Immunol (249), 249-270

 

Mythbusting 101: Organic Farming > Conventional Agriculture

People believe a lot of things that we have little to no evidence for, like that vikings wore horned helmets or that you can see the Great Wall of China from space. One of the things I like to do on my blogs is bust commonly held myths that I think matter. For example, I get really annoyed when I hear someone say sharks don’t get cancer (I’ll save that rant for another day). From now onward, posts that attack conventionally believed untruths will fall under a series I’m going to call “Mythbusting 101.”

USDA OrganicTen years ago, Certified Organic didn’t exist in the United States. Yet in 2010, a mere eight years after USDA’s regulations officially went into effect, organic foods and beverages made $26.7 billion. In the past year or two, certified organic sales have jumped to about $52 billion worldwide despite the fact that organic foods cost up to three times as much as those produced by conventional methods. More and more, people are shelling out their hard-earned cash for what they believe are the best foods available. Imagine, people say: you can improve your nutrition while helping save the planet from the evils of conventional agriculture – a complete win-win. And who wouldn’t buy organic, when it just sounds so good?

Here’s the thing: there are a lot of myths out there about organic foods, and a lot of propaganda supporting methods that are rarely understood. It’s like your mother used to say: just because everyone is jumping off a bridge doesn’t mean you should do it, too. Now, before I get yelled at too much, let me state unequivocally that I’m not saying organic farming is bad – far from it. There are some definite upsides and benefits that come from many organic farming methods. For example, the efforts of organic farmers to move away from monocultures, where crops are farmed in single-species plots, are fantastic; crop rotations and mixed planting are much better for the soil and environment. My goal in this post isn’t to bash organic farms, instead, it’s to bust the worst of the myths that surround them so that everyone can judge organic farming based on facts. In particular, there are four myths thrown around like they’re real that just drive me crazy.

Myth #1: Organic Farms Don’t Use Pesticides

When the Soil Association, a major organic accreditation body in the UK, asked consumers why they buy organic food, 95% of them said their top reason was to avoid pesticides. They, like many people, believe that organic farming involves little to no pesticide use. I hate to burst the bubble, but that’s simply not true. Organic farming, just like other forms of agriculture, still uses pesticides and fungicides to prevent critters from destroying their crops. Confused?

So was I, when I first learned this from a guy I was dating. His family owns a farm in rural Ohio. He was grumbling about how everyone praised the local organic farms for being so environmentally-conscientious, even though they sprayed their crops with pesticides all the time while his family farm got no credit for being pesticide-free (they’re not organic because they use a non-organic herbicide once a year). I didn’t believe him at first, so I looked into it: turns out that there are over 20 chemicals commonly used in the growing and processing of organic crops that are approved by the US Organic Standards. And, shockingly, the actual volume usage of pesticides on organic farms is not recorded by the government. Why the government isn’t keeping watch on organic pesticide and fungicide use is a damn good question, especially considering that many organic pesticides that are also used by conventional farmers are used more intensively than synthetic ones due to their lower levels of effectiveness. According to the National Center for Food and Agricultural Policy, the top two organic fungicides, copper and sulfur, were used at a rate of 4 and 34 pounds per acre in 1971 1. In contrast, the synthetic fungicides only required a rate of 1.6 lbs per acre, less than half the amount of the organic alternatives.

The sad truth is, factory farming is factory farming, whether its organic or conventional. Many large organic farms use pesticides liberally. They’re organic by certification, but you’d never know it if you saw their farming practices. As Michael Pollan, best-selling book author and organic supporter, said in an interview with Organic Gardening,

“They’re organic by the letter, not organic in spirit… if most organic consumers went to those places, they would feel they were getting ripped off.”

What makes organic farming different, then? It’s not the use of pesticides, it’s the origin of the pesticides used. Organic pesticides are those that are derived from natural sources and processed lightly if at all before use. This is different than the current pesticides used by conventional agriculture, which are generally synthetic. It has been assumed for years that pesticides that occur naturally (in certain plants, for example) are somehow better for us and the environment than those that have been created by man. As more research is done into their toxicity, however, this simply isn’t true, either. Many natural pesticides have been found to be potential – or serious – health risks.2

Take the example of Rotenone. Rotenone was widely used in the US as an organic pesticide for decades 3. Because it is natural in origin, occurring in the roots and stems of a small number of subtropical plants, it was considered “safe” as well as “organic“. However, research has shown that rotenone is highly dangerous because it kills by attacking mitochondria, the energy powerhouses of all living cells. Research found that exposure to rotenone caused Parkinson’s Disease-like symptoms in rats 4, and had the potential to kill many species, including humans. Rotenone’s use as a pesticide has already been discontinued in the US as of 2005 due to health concerns***, but shockingly, it’s still poured into our waters every year by fisheries management officials as a piscicide to remove unwanted fish species.

The point I’m driving home here is that just because something is natural doesn’t make it non-toxic or safe. Many bacteria, fungi and plants produce poisons, toxins and chemicals that you definitely wouldn’t want sprayed on your food.

Just last year, nearly half of the pesticides that are currently approved for use by organic farmers in Europe failed to pass the European Union’s safety evaluation that is required by law 5. Among the chemicals failing the test was rotenone, as it had yet to be banned in Europe. Furthermore, just over 1% of organic foodstuffs produced in 2007 and tested by the European Food Safety Authority were found to contain pesticide levels above the legal maximum levels – and these are of pesticides that are not organic 6. Similarly, when Consumer Reports purchased a thousand pounds of tomatoes, peaches, green bell peppers, and apples in five cities and tested them for more than 300 synthetic pesticides, they found traces of them in 25% of the organically-labeled foods, but between all of the organic and non-organic foods tested, only one sample of each exceeded the federal limits8.

Not only are organic pesticides not safe, they might actually be worse than the ones used by the conventional agriculture industry. Canadian scientists pitted ‘reduced-risk’ organic and synthetic pesticides against each other in controlling a problematic pest, the soybean aphid. They found that not only were the synthetic pesticides more effective means of control, the organic pesticides were more ecologically damaging, including causing higher mortality in other, non-target species like the aphid’s predators9. Of course, some organic pesticides may fare better than these ones did in similar head-to-head tests, but studies like this one reveal that the assumption that natural is better for the environment could be very dangerous.

Even if the organic food you’re eating is from a farm which uses little to no pesticides at all, there is another problem: getting rid of pesticides doesn’t mean your food is free from harmful things. Between 1990 and 2001, over 10,000 people fell ill due to foods contaminated with pathogens like E. coli, and many have organic foods to blame. That’s because organic foods tend to have higher levels of potential pathogens. One study, for example, found E. coli in produce from almost 10% of organic farms samples, but only 2% of conventional ones10. The same study also found Salmonella only in samples from organic farms, though at a low prevalence rate. The reason for the higher pathogen prevalence is likely due to the use of manure instead of artificial fertilizers, as many pathogens are spread through fecal contamination. Conventional farms often use manure, too, but they use irradiation and a full array of non-organic anti-microbial agents as well, and without those, organic foods run a higher risk of containing something that will make a person sick.

In the end, it really depends on exactly what methods are used by crop producers. Both organic and conventional farms vary widely in this respect. Some conventional farms use no pesticides. Some organic farms spray their crops twice a month. Of course, some conventional farms spray just as frequently, if not more so, and some organic farms use no pesticides whatsoever. To really know what you’re in for, it’s best if you know your source, and a great way to do that is to buy locally. Talk to the person behind the crop stand, and actually ask them what their methods are if you want to be sure of what you’re eating.

 

Myth #2: Organic Foods are Healthier

Some people believe that by not using manufactured chemicals or genetically modified organisms, organic farming produces more nutritious food. However, science simply cannot find any evidence that organic foods are in any way healthier than non-organic ones – and scientists have been comparing the two for over 50 years.

Just recently, an independent research project in the UK systematically reviewed the 162 articles on organic versus non-organic crops published in peer-reviewed journals between 1958 and 2008 11. These contained a total of 3558 comparisons of content of nutrients and other substances in organically and conventionally produced foods. They found absolutely no evidence for any differences in content of over 15 different nutrients including vitamin C, ?-carotene, and calcium. There were some differences, though; conventional crops had higher nitrogen levels, while organic ones had higher phosphorus and acidity – none of which factor in much to nutritional quality. Further analysis of similar studies on livestock products like meat, dairy, and eggs also found few differences in nutritional content. Organic foods did, however, have higher levels of overall fats, particularly trans fats. So if anything, the organic livestock products were found to be worse for us (though, to be fair, barely).

“This is great news for consumers. It proves that the 98% of food we consume, which is produced by technologically advanced agriculture, is equally nutritious to the less than 2% derived from what is commonly referred to as the ‘organic’ market,” said Fredhelm Schmider, the Director General of the European Crop Protection Association said in a press release about the findings.12

Joseph D. Rosen, emeritus professor of food toxicology at Rutgers, puts it even more strongly. “Any consumers who buy organic food because they believe that it contains more healthful nutrients than conventional food are wasting their money,” he writes in a comprehensive review of organic nutritional claims13.

Strong organic proponents also argue that organic food tastes better. In the same poll where 95% of UK organic consumers said they buy organic to avoid pesticides, over two-thirds of respondents said organic produce and meats taste better than non-organic ones. But when researchers had people put their mouths to the test, they found that people couldn’t tell the difference between the two in blind taste tests14, 18.

So, in short, organics are not better for us and we can’t tell the difference between them and non-organic foods. There may be many things that are good about organic farming, from increased biodiversity on farms to movement away from monocultures, but producing foods that are healthier and tastier simply isn’t one of them.

Myth #3: Organic Farming Is Better For The Environment

As an ecologist by training, this myth bothers me the most of all three. People seem to believe they’re doing the world a favor by eating organic. The simple fact is that they’re not – at least the issue is not that cut and dry.

Yes, organic farming practices use less synthetic pesticides which have been found to be ecologically damaging. But factory organic farms use their own barrage of chemicals that are still ecologically damaging, and refuse to endorse technologies that might reduce or eliminate the use of these all together. Take, for example, organic farming’s adamant stance against genetically modified organisms (GMOs).

GMOs have the potential to up crop yields, increase nutritious value, and generally improve farming practices while reducing synthetic chemical use – which is exactly what organic farming seeks to do. As we speak, there are sweet potatoes are being engineered to be resistant to a virus that currently decimates the African harvest every year, which could feed millions in some of the poorest nations in the world15. Scientists have created carrots high in calcium to fight osteoperosis, and tomatoes high in antioxidants. Almost as important as what we can put into a plant is what we can take out; potatoes are being modified so that they do not produce high concentrations of toxic glycoalkaloids, and nuts are being engineered to lack the proteins which cause allergic reactions in most people. Perhaps even more amazingly, bananas are being engineered to produce vaccines against hepatitis B, allowing vaccination to occur where its otherwise too expensive or difficult to be administered. The benefits these plants could provide to human beings all over the planet are astronomical.

Yet organic proponents refuse to even give GMOs a chance, even to the point of hypocrisy. For example, organic farmers apply Bacillus thuringiensis (Bt) toxin (a small insecticidal protein from soil bacteria) unabashedly across their crops every year, as they have for decades. It’s one of the most widely used organic pesticides by organic farmers. Yet when genetic engineering is used to place the gene encoding the Bt toxin into a plant’s genome, the resulting GM plants are vilified by the very people willing to liberally spray the exact same toxin that the gene encodes for over the exact same species of plant. Ecologically, the GMO is a far better solution, as it reduces the amount of toxin being used and thus leeching into the surrounding landscape and waterways. Other GMOs have similar goals, like making food plants flood-tolerant so occasional flooding can replace herbicide use as a means of killing weeds. If the goal is protect the environment, why not incorporate the newest technologies which help us do so?

But the real reason organic farming isn’t more green than conventional is that while it might be better for local environments on the small scale, organic farms produce far less food per unit land than conventional ones. Organic farms produce around 80% that what the same size conventional farm produces16 (some studies place organic yields below 50% those of conventional farms!).

Right now, roughly 800 million people suffer from hunger and malnutrition, and about 16 million of those will die from it17. If we were to switch to entirely organic farming, the number of people suffering would jump by 1.3 billion, assuming we use the same amount of land that we’re using now. Unfortunately, what’s far more likely is that switches to organic farming will result in the creation of new farms via the destruction of currently untouched habitats, thus plowing over the little wild habitat left for many threatened and endangered species.

Already, we have cleared more than 35% of the Earth’s ice-free land surface for agriculture, an area 60 times larger than the combined area of all the world’s cities and suburbs. Since the last ice age, nothing has been more disruptive to the planet’s ecosystem and its inhabitants than agriculture. What will happen to what’s left of our planet’s wildlife habitats if we need to mow down another 20% or more of the world’s ice-free land to accommodate for organic methods?

The unfortunate truth is that until organic farming can rival the production output of conventional farming, its ecological cost due to the need for space is devastating. As bad as any of the pesticides and fertilizers polluting the world’s waterways from conventional agriculture are, it’s a far better ecological situation than destroying those key habitats altogether. That’s not to say that there’s no hope for organic farming; better technology could overcome the production gap, allowing organic methods to produce on par with conventional agriculture. If that does occur, then organic agriculture becomes a lot more ecologically sustainable. On the small scale, particularly in areas where food surpluses already occur, organic farming could be beneficial, but presuming it’s the end all be all of sustainable agriculture is a mistake.

Myth #4: It’s all or none

The point of this piece isn’t to vilify organic farming; it’s merely to point out that it’s not as black and white as it looks. Organic farming does have many potential upsides, and may indeed be the better way to go in the long run, but it really depends on technology and what we discover and learn in the future. Until organic farming can produce crops on par in terms of volume with conventional methods, it cannot be considered a viable option for the majority of the world. Nutritionally speaking, organic food is more like a brand name or luxury item. It’s great if you can afford the higher price and want to have it, but it’s not a panacea. You would improve your nutritional intake far more by eating a larger volume of fruits and vegetables than by eating organic ones instead of conventionally produced ones.

What bothers me most, however, is that both sides of the organic debate spend millions in press and advertising to attack each other instead of looking for a resolution. Organic supporters tend to vilify new technologies, while conventional supporters insist that chemicals and massive production monocultures are the only way to go. This simply strikes me as absurd. Synthetic doesn’t necessarily mean bad for the environment. Just look at technological advances in creating biodegradable products; sometimes, we can use our knowledge and intelligence to create things that are both useful, cheap (enough) and ecologically responsible, as crazy as that idea may sound.

I also firmly believe that increasing the chemicals used in agriculture to support insanely over-harvested monocultures will never lead to ecological improvement. In my mind, the ideal future will merge conventional and organic methods, using GMOs and/or other new technologies to reduce pesticide use while increasing the bioavailability of soils, crop yield, nutritional quality and biodiversity in agricultural lands. New technology isn’t the enemy of organic farming; it should be its strongest ally.

As far as I’m concerned, the biggest myth when it comes to organic farming is that you have to choose sides. Guess what? You don’t. You can appreciate the upsides of rotating crops and how GMOs might improve output and nutrition. You, the wise and intelligent consumer, don’t have to buy into either side’s propaganda and polarize to one end or another. You can, instead, be somewhere along the spectrum, and encourage both ends to listen up and work together to improve our global food resources and act sustainably.

 

See more on this, in response to critiques: In the immortal words of Tom Petty: “I won’t back down”

More Mythbusting 101:

Sharks will cure cancer

*** Oh, it turns out Rotenone got re-approved for organic use in 2010. See for yourself.

Regarding the use of GMOs: perhaps Andy Revkin from The New York Times says it better.

Based on the responses, I just want to make this clear: this is NOT a comprehensive comparison of organic and conventional agriculture, nor is it intended to be. That post would be miles long and far more complex. My overall belief is that there shouldn’t be a dichotomy in the first place – there are a variety of methods and practices that a farmer can use, each with its pros and cons. The main point here is that something “organic” isn’t intrinsically better than something that isn’t, and that you have to approach all kinds of agriculture critically to achieve optimum sustainability.

Ok, and while I’m adding in notes: stop citing Bedgley et al. 2007 as evidence that organic farming produces equal yields: this study has been shown to be flawed (see my comments in the follow up post to this article), and was strongly critiqued (e.g. this response article).

 

ResearchBlogging.orgReferences

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