Jessica Shade, Ph.D., started her involvement in the organic movement as an undergraduate at the University of California, Santa Cruz, where she was a co-owner of the Kresge Natural Foods Cooperative. During her time there, she developed a deep interest in the science supporting the environmental, public health, and cultural benefits of organic practices, and that passion followed her through her graduate career at the University of California, Berkeley, where she received a Ph.D. in Integrative Biology. Most of her research focuses on conservation ecology, population genetics, and selective landscapes, but she also has experience studying effective restoration techniques, plant secondary compounds, and microbial symbiosis.
In 2013, Jessica joined The Organic Center, a non-profit organic research and education organization, as director of science programs.
“We’re getting exposed to a cocktail of residues,” says Jessica. “And what’s scary is there hasn’t been a lot of research on the health effects of multiple pesticide exposure. But just lately more researchers are starting to get interested in this, because they’re finding that pesticides can have a synergistic effect on human health.” This means that if we are exposed to two different pesticides, our bodies don’t simply experience the effects of one pesticide at a time, separately; effects get compounded, and they can completely change, when chemicals are combined. “You can get completely new negative effects that are worse than the individual, isolated effects from exposure to both of those pesticides,” she says.
In this interview, Jessica and Theresa talk about the myriad of factors at play in our environment and the connections between chemical and organic agriculture, pollinators, carbon sequestration, our food, human health, and more.There’s a lot going on in this short conversation! Let us know in the comments what you think!
To learn more about current organic research check out Rootstock.coop/grass-up.
Transcript: Rootstock Radio interview with Jessica Shade
May 4, 2015
Welcome to Rootstock Radio. Join us as host Theresa Marquez talks to leaders from the Good Food movement about food, farming, and our global future. Rootstock Radio—propagating a healthy planet. Now, here’s host Theresa Marquez.
TM: Hello, listeners. Today, as our guest, we have Jessica Shade, the director of science programs for the Organic Center. Ten years ago I helped co-found the Organic Center. Many of us had been observing organic production practices and we knew they worked, but we wanted the science behind it. I hope you enjoy this conversation with Jessica Shade today.
Today I’m just so delighted to have as my special guest Jessica Shade, who is the senior research scientist for the Organic Center. And we will learn more about the Organic Center as we speak. And I just want to say thank you so much, Jessica, for talking with me today, and welcome!
JESSICA SHADE: Thank you so much for having me. I’m really excited to be here talking with you.
TM: Yeah, and I know that you and I love this topic, so we’re going to have lots of fun talking about it. Jess, you know, I had so much fun reading your bio. And of course you went to school in one of my most favorite places, Santa Cruz. What made you want to go to Santa Cruz to school?
JS: You know, it’s kind of funny, because when you just said that it’s going to be fun even though we’re talking about organic research, it struck a note with me because I actually used to hate science. I grew up with my family—my mom’s Latina, so I grew up in a little bit less traditional of a community than your typical scientist, and I just had no interest in science. And my mom’s from Argentina, so I went down to Argentina and was spending some time with my aunts down there. And they’re my great aunts, so they’re in their nineties. So going down there and hearing their stories about being, first of all, women getting their PhDs in this pretty machismo country, back in the 1940s, when women just weren’t getting PhDs, especially in science—and they’re also Jewish, so they were battling anti-Semitism at the same time—made me think, if they can do it, I owe it to myself to challenge myself to be a scientist. So it was kind of multiple things coming together in my life.
TM: And of course, the specific research that Jessica is involved in is organic, benefits of organic, and certainly around food and food’s impact on the environment. And Jessica, how long have you worked for the Organic Center?
JS: Almost two years now. I feel like, in such a short time, I’ve become so surrounded by the organic community and the organic research. It’s been really exciting.
TM: So tell us about the Newcastle study then. And this was a meta-analysis that had to do with organic, some findings of organic. And so why don’t you tell us a little bit more about it?
JS: Sure. So the findings showed that organic crops have higher levels of antioxidants, lower levels of toxic metals—they specifically looked at cadmium—and fewer pesticides than conventional. An antioxidant helps fight the oxidative process. So these—I’m not sure if you’ve ever heard of free radicals. Those can cause a lot of damage in your system. So antioxidants help fight free radicals.
TM: Like cancer, right?
JS: Yes. So there are a lot of processes that are affected by free radicals, like cancer, so a lot of sun damage, for example, free radicals happening, and inflammatory diseases. There are a lot of problems associated with oxidative stress. And so this study looked at specific antioxidants that have been linked to decreases in chronic disease risks such as cardiovascular disease, neurodegenerative disease, certain cancers. And the results suggest that a switch from conventional to organic crop consumption could result in a 20 to 40 percent increase in crop-based antioxidant intake. So that means that the amount of antioxidants that you’d consume every day by eating the recommended five servings of organic rather than conventional fruit and vegetables would be equal to one or two whole servings of fruit and vegetables. So a lot of times people look at these studies, and they’re looking at these antioxidants, and they think, oh, does this really have an effect on my everyday life? Well, the answer for this one is yes!
TM: Wow. And so is the bottom line here, maybe we’re not going to say, “Yes, do this and you’ll never get cancer,” but is the bottom line that it really improves your immune system?
JS: I don’t like to talk about it in terms of preventing these diseases or protecting yourself from these diseases. It’s all about risk. So decreasing your risk. Who knows, I may get diseases, but the risk of getting those, having those health problems is decreased by eating organic.
TM: Do you think that, you know, if there were more studies, that there could be more conclusive results or conclusions that we can make about it? I mean, I already am very dedicated to organic for a lot of different reasons, and eat organic, and I think you do too, for a lot of different reasons. This certainly is another one. Would you say that probably this study will probably stimulate more research on antioxidants?
JS: Definitely. And if you read any research article to its conclusion, almost every one says, “What this study shows is that we need more research in this topic area.” And this is no exception. And I think what’s great about this research is that it’s getting people interested, and more researchers are reading this sort of data and getting ideas for how to retool the data and do more research in the area.
TM: The cadmium—you know, maybe some of our listeners don’t realize just how much food carries heavy metals in it. And I’m sorry to say this, but some of our favorite food, like asparagus, often will have levels of cadmium in it that probably are not desirable.
JS: That’s true. And they were looking at very small levels. So what they found is that organic crops actually had 48 percent lower cadmium than conventional crops, which sounds like a lot. Most crops don’t have high levels of cadmium, but the problem is that cadmium can accumulate in the body. So even at low levels, chronic exposure can be dangerous. And for those of you who don’t know what cadmium is, it’s a highly toxic metal that can cause kidney failure, bone softening, and liver damage. So it’s a pretty scary one.
TM: I know that conventional asparagus, I’ve seen some test results, can often have higher levels of cadmium. It’s very common.
TM: So what about the third, and that of course is the one that may be the most terrifying for me, and that is, what was found in the difference between pesticides in the organic versus non-organic?
JS: Conventional crops were four times less [correction: more] likely than organic crops to contain pesticide residues. So what that means to me is that the organic standards are working. So the organic standards don’t allow organic growers to use pesticides, but a lot of people wonder if those are actually working, if those are protecting you from being exposed to pesticide residues. So this study is conclusive proof that yes, they’re working.
TM: Okay, so let me back up a little bit so I understand. So organic had four times less pesticides. And did they test for specific or just in general, across the board pesticides?
JS: So they looked at the frequency of residues. So it’s not even that organic had four times less pesticides. It’s that organic produce were four times more likely to have no pesticide residues at all than conventional.
TM: Oh, okay. Wasn’t there another research study by a Professor or Dr. Lu from Harvard that also showed less pesticides in the urine of children?
JS: That’s right. So what he did is he looked at children who were eating a conventional diet and measured the pesticide levels of their urine. And then he put them on an organic diet for a week and measured the pesticide levels in their urine, and they were almost nonexistent. It was amazing what a difference eating organic for that short a period of time had on these children.
TM: Well, you know, I wore my family down, and so they actually—it took me a long time but they now are organic advocates. But you know, in the beginning, they would say to me, like, “We don’t have to worry about that. The USDA protects us.”
JS: My response is usually, “When would you want to be exposed to pesticide residues?” And one of the examples I use is DDT. So we used to think that was completely safe; we even sprayed it on children. So if you go online and you search “DDT” you’ll find all these pictures of trucks running down the street, spraying DDT, with kids playing in it, or DDT being sprayed over pools with kids swimming in it. And now we know that DDT is carcinogenic, it reduces reproductive success, it’s an endocrine disrupter. I mean, I have a list a mile long of the health problems associated with DDT.
And it’s very difficult to have studies on a short time scale about pesticide health problems. And a lot of the pesticides that we’re using now are pretty scary because they’re new and the tests that are being done on them are being done on the time frame of months rather than years or generations. And there’s even a concept that’s just starting to be published about called “disease inheritance.” And the way it works is that if you’re exposed to a certain chemical, then you’ll have your health problems, but you can actually pass those products on to your children and grandchildren and great-grandchildren.
JS: Yeah, and they’ve been studying it in mice so far. I haven’t seen any human studies because it’s very difficult to do generational studies. But it’s pretty striking results. And they actually did a study with DDT on mice, where they fed mice, or they exposed mice to DDT, and then they looked four generations down the line—so the mice’s great-great-great-grandbaby mice—and those offspring had higher rates of obesity. Which is fascinating, because—
JS: Yeah, those baby mice had never been exposed to DDT, but they were still showing symptoms from having their ancestors exposed to it.
TM: Wow, so are you saying that—well, this is probably one of those things of more research is needed—but that there might be a connection between obesity and exposure to different kinds of pesticides?
JS: Yes, especially with endocrine disruptors.
TM: Well, just for a second, because the endocrine gland is something that regulates, I believe, our weight and our sexual hormones. Is that right?
JS: Mm-hmm, that’s right.
TM: And so the little bit of science that I know and have read about has been that minute, in fact parts per billion, of certain pesticides mimic hormones and then interfere with the proper endocrine releases, or the way the endocrine system is supposed to work. It can interfere with that.
JS: Right, it’s becoming a hot topic. But that’s exactly right. It can mimic hormones like estrogen and then cause difficulties when you’re trying to have children. And it’s especially important for pregnant women and children or people who are thinking about having kids to avoid pesticides, because they can have a disproportionate adverse effect on the developing immune system. And there have been several reports that have pointed to this. So there’s this joint report by the American College of Obstetricians and Gynecologists and the American Society for Reproductive Medicine that suggest that environmental chemicals such as pesticides are a risk to pregnancy.
TM: When I grew up, which was in the 1950s and 1960s, nobody took fertility drugs. And I think that, I don’t know whether we can quantify it, but I do think that it’s becoming very, very common. And I just wondered, hasn’t 2,4-D also been widely tested?
JS: Yes. Exposure to 2,4-D is, there are several studies out there showing that there are serious risks associated with exposure. But even more scary than just the health risks associated with 2,4-D is the fact that now, like you said, we’re not just going to be exposed to one chemical at a time. We’re getting exposed to a cocktail of residues. And what’s scary is there hasn’t been a lot of research on the health effects of multiple pesticide exposure.
But just lately more researchers are starting to get interested in this, because they’re finding that pesticides can have a synergistic effect on human health. So when you’re exposed to one pesticide, you don’t just get the negative effects from that pesticide and then you’re exposed to another, and negative effects from that. You can get completely new negative effects that are worse than the individual, isolated effects from exposure to both of those pesticides.
TM: And so how about that? Is there enough research being done by the USDA and the EPA that make us feel that whenever we combine all these pesticides in the foods that we’re eating, even if they are very low doses, that… I mean, that seems like it would be very expensive and difficult research to do.
JS: It is very expensive. It’s very difficult, because every time you add another chemical into the mix it’s a whole other variable. So there isn’t very much research out there. And it’s scary how little research there is, especially because every single study that I see that looks at it has extremely worrying results.
There was another study that was also released this year, showing that the inert ingredients can increase pesticide toxicity to humans. And that study came out of France, and it showed that inert ingredients can increase toxicity by up to 1,000 times higher than the active ingredients alone. So when they look at the pesticide toxicity levels and the levels that are allowed for human consumption, they’re only looking at active ingredients.
TM: So they’re not… Inert means that it isn’t active. It supposedly just helps facilitate it.
What about the bees and the butterflies? Are they the canary in the cage on these things?
JS: Yes. So, as many people know, pollinators have been decreasing over the last decade, and a lot of people are very worried about the bees. And more and more research is coming out, showing that exposure to pesticides is the main cause of the decrease in bee populations.
And when you think about pollinators getting exposed to pesticides, it’s important to remember that it’s not just high levels of pesticides that are harming bees. So it’s not just acute toxicity, where a bee will land on a flower and keel over dead from the high levels of pesticides. Even low levels of pesticides, when bees are exposed to them chronically, over and over again, it can have small effects that really build up. It can have effects on the bees’ immune system; it can disorient the bees, making it more difficult for them to find flowers or communicate with their hive about where the flowers are.
TM: Or get back to their hive.
JS: Or get back to their hive! So there are all these very complicated aspects of bee colonies that pesticides are affecting. And colony collapse disorder is one of the scariest things, because you’re seeing entire hives disappear. And just this year, a study came out by Dr. Lu, whom you mentioned earlier, showing that neonicotinoids, which is a class of pesticide that is very commonly used and it’s becoming more and more common, can mimic the signs of colony collapse disorder. So that means that it’s very likely that neonicotinoids are one of the main causes of the disappearance of beehives.
TM: I’m very excited about the research that’s emerging now on the benefits of organic that have to do with organic’s ability to mitigate climate change. And I don’t know—Jessica, you know much more about it—but can you talk to us a little bit about what you do know about the kinds of studies that we’re seeing now?
JS: Sure. And this is one of the best success stories out there. And one of the reasons that organic is so good when it comes to mitigating climate change is because of the amount of carbon that gets sequestered in the soil. So organic farming really creates healthy soil with a lot more sequestered carbon.
TM: So just stop for a second just to make sure that everyone understands sequestered. It means just holding it in or sinking it in.
JS: Yes, so all the CO2 that’s in the atmosphere that’s causing this climate change to happen gets trapped in the soil, and it’s no longer in our atmosphere. And the Rodale Institute actually just released a paper showing that the carbon sequestration from organic conversion could completely account for the carbon release from human sources. So it was this very inspirational paper that shows that organic can have this huge effect on climate change mitigation.
TM: And certainly that has a lot to do with the soil, but also—I’m very much devoted to, of course, pasture and pasture-raised livestock.
JS: Yes, conversion to pasture is a great way to sequester more carbon. And the Organic Center actually has a research project right now that’s looking at sequestered carbon in organic soils, and part of that is going to look at pasture. So right now we’re looking at all-organic, but in the future we’d like to use that as a baseline research study to do spinoff studies. So looking at pasture, looking at specialty crops, looking at all these different crop-raising and organic-farming systems to see how to increase the amount of sequestered carbon in your farm or in the world in general. In California they just started this cap-and-trade program for carbon trading and carbon offsets. And my dream is for organic farmers to get carbon credits for farming organically.
TM: Didn’t Rodale also do a study with soil? Besides the fact that good, good soil will help sink carbon, but won’t it also hold water?
JS: Yes, and that’s another thing that we’re looking at with the study, where our soil health study right now is looking at humic acid. And humic acid is the part of soil that gives it all of these very good qualities. It’s part of organic matter, and it helps with things like holding water. And that’s very important for resilience—resilience to extreme weather events like drought, which are caused by climate change. So it’s another positive story about the benefits of organic when it comes to climate change, because even if we completely reduce or even negate the amount of carbon that’s going out into the atmosphere, we’re still going to see some climate change because this has been happening for a while. But with organic farming you actually find that plants are more resilient to the effects of climate change.
TM: I guess I’m going to say—well, I can hear my naysayers now saying, “But we need pesticides because we have to feed the world, and organic can’t do that.” What do you think, Jessica?
JS: It’s all about food waste. I think when people talk about lower yields in organic, they’re completely missing the picture, because we are making so much food in the world but we’re wasting so much of it. And one of our other projects looks at nitrogen pollution, but one of the interesting things to come from that study is the number one way to reduce your impact is to reduce food waste. So there’s plenty of food out there—it’s just that food is getting wasted on a massive scale.
Also, another interesting research trend that I’ve been seeing is, the longer farms are kept in organic management, the higher the yields. And that’s one of the things that’s interesting about some of the research that shows low yields in organic, is a lot of those are looking on very short time scales. So there’s starting to be research that’s published on long-term scales, so fifteen, twenty years, and they’re showing that the more you use best practices in organic management, the higher your yields are going to be.
Looking into the future, another thing that makes me very sad when people talk about organic not being able to feed the world is that it’s a very shortsighted view. Because if you look in the future, if you look at the kind of environmental consequences that come from conventional agriculture, if you look down the road, decades down the road, conventional agriculture is going to destroy our ability to create food at all.
Sticking to successes, one of the successes this year was the Farm Bill. And the Farm Bill provided a lot of research specifically for organic. But the amount of research that was provided is just a fraction of the amount of organic agriculture that’s being consumed. So it’s still just a drop in the bucket of what we need. So I think it’s important for the public to get involved.
And one of the ways they can get involved is by, first of all, choosing organic. So consumer choice speaks volumes when it comes to deciding where the funding goes for research, so choose organic. You can also help fund organizations, because every small bit helps. And this year the Organic Center had a crowdfunding campaign that was wildly successful, because people care so much about this. So we put together a crowdfunding campaign for citrus greening—you can look on our website to find out more about citrus greening problems. And people were really eager to support agricultural methods that don’t use toxic pesticides, that aren’t using synthetic fertilizers, that are healthy for both humans and the environment and pollinators.
TM: Well, you know, Carlo Petrini, who was the founder of Slow Food, he said that we shouldn’t think of ourselves as consumers. In fact, I love his quote. He said better cut your tongue out before you refer to yourself as a consumer. You’re a co-producer. So I think what you just said is some people who probably woke up and said, “I’m a co-producer; I think I’ll co-fund.” So that’s a really great story.
Jessica, it’s been really fun talking with you about this. And even though I think some of this is hard for us to—many of us, I know sometimes there are days when I feel like, oh, I don’t want to hear about this. But I also think that when we make informed choices, that feels good. So even though sometimes this is hard to hear, it’s much better to make an informed choice. And so for those out there who want more information, can you give your website again?
JS: Sure. It’s www.organic-center.org. And one of the things we do is any study that’s getting published out there that has to do with things that the organic community might be interested in, we translate that from scientific jargon into nontechnical terms. So we basically give you the bottom line of these research results. So if you look on our website, things are changing daily. We update it every day with new research. So check it out.
TM: That is really fantastic. And I so want to thank you for all the good work you’re doing on behalf of organic and all its research, so that we can be informed about the food that we eat. So thank you, Jessica, so much.
JS: It’s been so fun. Thank you so much for having me, Theresa.
TM: Thank you Jessica, for your wonderful contributions. And thank you, listeners, for tuning in. Until next week!