Pesticides in Fruits and Vegetables

[daniellewiley]

A couple of weeks ago, my husband sent me to this site:

Food News

A quote from the site:

Most Contaminated: The Dirty Dozen

Consistent with two previous EWG investigations, fruits topped the list of the consistently most contaminated fruits and vegetables, with eight of the 12 most contaminated foods. Among the top six were four fruits, with peaches leading the list, then strawberries, apples and nectarines. Pears, cherries, red raspberries, and imported grapes were the other four fruits in the top 12. Among these eight fruits:

Nectarines had the highest percentage of samples test positive for pesticides (97.3 percent), followed by pears (94.4 percent) and peaches (93.7 percent).

Nectarines also had the highest likelihood of multiple pesticides on a single sample — 85.3 percent had two or more pesticide residues — followed by peaches (79.9 percent) and cherries (75.8 percent).

Peaches and raspberries had the most pesticides detected on a single sample with nine pesticides on a single sample, followed by strawberries and apples, where eight pesticides were found on a single sample.

Peaches had the most pesticides overall with some combination of up to 45 pesticides found on the samples tested, followed by raspberries with 39 pesticides and apples and strawberries, both with 36.

Spinach, celery, potatoes, and sweet bell peppers are the vegetables most likely to expose consumers to pesticides. Among these four vegetables:

Celery had the highest of percentage of samples test positive for pesticides (94.5 percent), followed by spinach (83.4 percent) and potatoes (79.3 percent).

Celery also had the highest likelihood of multiple pesticides on a single vegetable (78 percent of samples), followed by spinach (51.8 percent) and sweet bell peppers (48.5 percent).

Spinach was the vegetable with the most pesticides detected on a single sample (10 found on one sample), followed by celery and sweet bell peppers (both with nine).

Sweet bell peppers were the vegetable with the most pesticides overall with 39, followed by spinach at 36 and celery and potatoes, both with 29.

I realize that it is sponsored by Stonyfield, and that they have an alterior motive, but the studies and information posted on the site were really a wake up call to me. I am now terrified of eating certain foods non-organic, and that is pretty hard to do here in Toledo. I try to go to Ann Arbor frequently to stock up at Trader Joe's and Whole Foods, but it's not always convenient.

What do you all think? This has totally changed the way I eat, so I'm curious to read your opinions here.

[shelora]

Mad cow, avian flu, pesticides, Monsanto, GMO, the fear factor list goes on and on. Pretty soon you realize, we are all doomed.

I've eaten organic produce that tasted awful and probably pesticide ridden carrots that tasted wonderful and vice versa.

I also wash my fruits and vegetables before I eat them which may or may not do anything, - hey, isn't the tap water filled with chlorine?- but the bottom line is, we all have to eat.

It's a whole lot better to eat fresh fruits and vegetables than fast food or pre-packaged meals and those high in salt, fat and sugar.

Best bet where I live is to purchase food from local farms throughout the seasons. They may not be certified organic but the farms don't use pesticides and the food is super fresh.

Another way out is to start a small garden in your backyard or deck.

Keep the faith.

[daniellewiley]

Mad cow, avian flu, pesticides, Monsanto, GMO, the fear factor list goes on and on. Pretty soon you realize, we are all doomed.

I've eaten organic produce that tasted awful and probably pesticide ridden carrots that tasted wonderful and vice versa.

I also wash my fruits and vegetables before I eat them which may or may not do anything, - hey, isn't the tap water filled with chlorine?-  but the bottom line is, we all have to eat.

It's a whole lot better to eat fresh fruits and vegetables than fast food or pre-packaged meals and those high in salt, fat and sugar.

Best bet where I live is to purchase food from local farms throughout the seasons. They may not be certified organic but the farms don't use pesticides and the food is super fresh.

Another way out is to start a small garden in your backyard or deck.

Keep the faith.

←

I should probably state that I'm not really an alarmist type of person - this site just really got to me. We don't eat processed or fast food (except on rare, rare occasions), so it's not an issue for me of produce or not produce. Some issues I HAVE run into include telling my daughter she can't have strawberries yet b/c I can't afford organic strawberries in March (oh my god, are those expensive).

I always buy local when I can, but I don't really know that the local farms don't use pesticides. One of the local apple farms for SURE does - I've read interviews with them in the paper, and they use every pesticide you can imagine. So, I do love buying local, but if I'm doing so at the local fruit and veggie market and not at the farmer's market, I'm not able to question the farmer. And, we do have an organic garden ourselves, but being in Toledo, that's only for summer/early fall.

[fou de Bassan]

Danielle,

I sympathize with you completely. We, too, try to avoid pesticide-laden produce but in the midwest that isn't always an option that's affordable or convenient. OUr solution is to provision as much organic as we can and prepare what we can't carefully. I would suggest joining a co-op as that can lower costs considerably. And pester, pester, pester your local grocer to have things like organic potatoes and carrots on regular order. Then support them. this past autumn the organic lettuce at our grocer was actually less expensive than regular lettuce.

There are also CSA's and mail-order firms on the internet that have great produce but they tend to be expensive. (We do use them in Jan. and Feb. when there is little to be had in the stores.)

fou

[Patrick S]

What do you all think? This has totally changed the way I eat, so I'm curious to read your opinions here.

←

The reason that I am not afraid of synthetic pesticides residues in produce is that the amount of endogenous pesticides in produce -which standard toxicological tests show are just as toxic as synthetic pesticides- is roughly 10,000 times greater than that of synethetic pesticide residues. I don't really see it as worthwhile to spend ~50% more for produce that has only 0.01% less total pesticide content. Lois Gold and Thomas Ames, two of the world's leading toxicologists (Ames is the inventor of the 'Ames test' and the head of the National Toxicology Project), have written a lot on the matter, and managed to completely change my mind. In a 2002 summary of their work, they wrote:

Of all dietary pesticides that humans eat, 99.99% are natural: these are chemicals produced by plants to defend themselves against fungi, insects, and other animal predators (Ames & al. 1990a; Ames & al. 1990b). Each plant produces a different array of such chemicals. On average, the Western diet includes roughly 5,000 to 10,000 different natural pesticides and their break-down products. Americans eat about 1,500 mg of natural pesticides per person per day, which is about 10,000 times more than they consume of synthetic pesticide residues (Ames & al. 1990b). Even though only a small proportion of natural pesticides has been tested for carcinogenicity, half of those tested (38/72) have been found to be carcinogenic in rodents; naturally occurring pesticides that are rodent carcinogens are ubiquitous in fruits, vegetables, herbs, and spices (Gold & al. 1997b; Gold & al. 1992) (table 2). Cooking of foods produces burnt material—about 2,000 mg per person per day—that also contains many rodent carcinogens.

In contrast, the residues of 200 synthetic chemicals measured by United States Federal Drug Administration, including the synthetic pesticides thought to be of greatest importance, average only about 0.09 mg per person per day (Ames & al. 1990a; Gold & al. 1997b; Gold & al. 1992). In a single cup of coffee, the natural chemicals that are rodent carcinogens are about equal in weight to an entire year’s worth of synthetic pesticide residues that are rodent carcinogens, even though only 3% of the natural chemicals in roasted coffee have been adequately tested for carcinogenicity (Gold & al. 1992) (table 3). This does not mean that coffee or natural pesticides are a cancer risk for humans,but rather that assumptions about high-dose animal can cer tests for assessing human risk at low doses need reexamination. No diet can be free of natural chemicals that are rodent carcinogens (Gold & al. 1999; Gold & al. 1997b; Gold & Zeiger 1997).

Personally, I see the text quoted from FoodNews as being enormously misleading, in that it doesn't bother to say that no plant can ever be pesticide free, and that synthetic pesticides residues are vanishingly small compared to levels of endogeous plant pesticides.

Basically, I believe in buying fresh, and I believe in buying local, but I wont pay extra for 'organic' certification.

[daniellewiley]

Personally, I see the text quoted from FoodNews as being enormously misleading, in that it doesn't bother to say that no plant can ever be pesticide free, and that synthetic pesticides residues are vanishingly small compared to levels of endogeous plant pesticides.

I'd love for you to read through the whole site and then give me your feedback. I've been in marketing for 10 years, so I always choose the most alarming/alarmist quote .

One of my big concerns with synthetic pesticide is that they are generally petrochemical based, and that petrochemicals can raise our estrogen levels - not a good thing.

[fifi]

. . . . .

One of my big concerns with synthetic pesticide is that they are generally petrochemical based, and that petrochemicals can raise our estrogen levels - not a good thing.

←

Huh? There are some compounds derived from petroleum that can mimic estrogen but the jury is still out on that. Those compounds also occur in plants. And, you can make the same thing from plant products, as in cellulose. It doesn't matter where it comes from, the carbon atoms and hydrogen atoms hook up the same way.

For a layman's take on the issue that Patrick S referenced, check out Jeffrey Steingarten's essay "Salad the Silent Killer" in his book The Man Who Ate Everything. It is quite entertaining.

If you were to believe every hyped story out there, you would expect to see bodies littering the streets. Actually, I saw a story recently that the life expectancy in the developed world has gone up again. So I buy what is fresh and delicious looking and don't really care where it came from. I do pay particular attention to washing something that is labeled "organic" though. Who knows what it was fertilized with.

[daniellewiley]

Huh? There are some compounds derived from petroleum that can mimic estrogen but the jury is still out on that. Those compounds also occur in plants. And, you can make the same thing from plant products, as in cellulose. It doesn't matter where it comes from, the carbon atoms and hydrogen atoms hook up the same way.

As someone who has had a history of issues related to estrogen dominance, I try to be very careful about this, whether or not it is 100% proven or not. Why risk it? If they mimic estrogen and cause my body to go into a state of estrogen dominance, I'm going to have more migraines, more cysts, etc. It's not worth it to me or my family. It's the same reason I don't microwave things in plastic containers.

Thanks for mentioning the Steingarten piece. I'll need to check it out - I'm a big fan of his.

[fifi]

. . . . .

As someone who has had a history of issues related to estrogen dominance, I try to be very careful about this, whether or not it is 100% proven or not. Why risk it? If they mimic estrogen and cause my body to go into a state of estrogen dominance, I'm going to have more migraines, more cysts, etc. It's not worth it to me or my family. It's the same reason I don't microwave things in plastic containers.

. . . . .

←

As a person that is sensitive to things like that, some research into where those compounds occur naturally might be in order. Plants are the most amazing chemical plants on earth (pun intended?) and make that Dupont or whosever tangle of pipes and big round things look like a rank amateur. Mimicking hormones is one of their tricks to affect the development of the insects that bite 'em.

[Patrick S]

One of my big concerns with synthetic pesticide is that they are generally petrochemical based, and that petrochemicals can raise our estrogen levels - not a good thing.

←

This is another subject on which there are alot of misconceptions. The estrogenic potency of synthetic pesticides residues are again vanishingly small compared to the estrogenic potency of many of our dietary components. Gold and Ames (2002) discuss this as well. I'm not saying don't worry, but I would caution against the misconception that all or even most of the hormonally active things we need to worry about are synthetic. A glass of soymilk or wine, for instance, has thousands of times the estrogenic potential of any synthetic pesticides residue from any serving of produce.

The trace exposures to estrogenic organochlorine resi dues are tiny compared to the normal dietary intake of naturally occurring endocrine-active chemi cals in fruits and vegetables (Safe 1995; Safe 1997; Safe 2000). These low levels of human exposure seem toxicologically implausible as a signifi cant cause of cancer or of reproductive abnormalities (Reinli & Block 1996; Safe 1995; Safe 1997; Safe 2000). Recent epidemiological studies have found no association between organochlorine pesticides and breast cancer, including one in which DDT, DDE, dieldrin, and chlordane were measured in blood of women on Long Island (Gammon & al. 2002). . .

Some recent studies have compared estrogenic equivalents (EQ) of dietary intake of syn thetic chemicals to phytoestrogens in the normal diet, by considering both the amount humans consume and estrogenic potency. Results support the idea that synthetic residues are orders of magnitude lower in EQ and are generally weaker in potency. One study used a series of in vitro as says and calculated the EQs in extracts from 200 ml of Cabernet Sauvignon wine and the EQs from average intake of organochlorine pesticides (Gaido & al. 1998). EQs for a single glass of wine ranged from 0.15 to 3.68 µg/day compared to 1.24 ng/day for organochlorine pesticides (Gaido & al. 1998); thus, the organochlorine residues are roughly 1,000 times less.

That's from pages 87-88 of Gold et al, Misconceptions About the Causes of Cancer. Fraser Institute, Risk Controversy Series, available from:

Here.

[Patrick S]

For a layman's take on the issue that Patrick S referenced, check out Jeffrey Steingarten's essay "Salad the Silent Killer" in his book The Man Who Ate Everything. It is quite entertaining.

←

Ruth Kava has a funny article along the same lines, pointing out just a few of the all-natural carcinogens present in a typical holiday meal. I read it a few years ago, and it really got me thinking. Here are some of the examples she gives of known carcinogens in food we eat all the time:

Acetaldehyde (apples, bread, coffee, tomatoes)—mutagen and potent rodent carcinogen

Acrylamide (bread, rolls)—rodent and human neurotoxin; rodent carcinogen

Aflatoxin (nuts)—mutagen and potent rodent carcinogen; also a human carcinogen

Allyl isothiocyanate (arugula, broccoli, mustard)—mutagen and rodent carcinogen

Aniline (carrots)—rodent carcinogen

Benzaldehyde (apples, coffee, tomatoes)—rodent carcinogen

Benzene (butter, coffee, roast beef)—rodent carcinogen

Benzo(a)pyrene (bread, coffee, pumpkin pie, rolls, tea)—mutagen and rodent carcinogen

Benzofuran (coffee)—rodent carcinogen

Benzyl acetate (jasmine tea)—rodent carcinogen

Caffeic acid (apples, carrots, celery, cherry tomatoes, cof-fee, grapes, lettuce, mangos, pears, potatoes)—rodent carcinogen

Catechol (coffee)—rodent carcinogen

Coumarin (cinnamon in pies)—rodent carcinogen

1,2,5,6-dibenz(a)anthracene (coffee)—rodent carcinogen

Estragole (apples, basil)—rodent carcinogen

Ethyl alcohol (bread, red wine, rolls)—rodent and human carcinogen

Ethyl acrylate (pineapple)—rodent carcinogen

Ethyl benzene (coffee)—rodent carcinogen

Ethyl carbamate (bread, rolls, red wine)—mutagen and rodent carcinogen

Furan and furan derivatives (bread, onions, celery, mushrooms, sweet potatoes, rolls, cranberry sauce, coffee)—many are mutagens

Furfural (bread, coffee, nuts, rolls, sweet potatoes)—furan derivative and rodent carcinogen

Heterocyclic amines(roast beef, turkey)—mutagens and rodent carcinogens

Hydrazines (mushrooms)—mutagens and rodent carcinogens

Hydrogen peroxide (coffee, tomatoes)—mutagen and rodent carcinogen

Hydroquinone (coffee)—rodent carcinogen

d-limonene (black pepper, mangos)—rodent carcinogen

4-methylcatechol (coffee)—rodent carcinogen

Methyl eugenol (basil, cinnamon and nutmeg in apple and pumpkin pies)—rodent carcinogen

Psoralens (celery, parsley)—mutagens; rodent and human carcinogens

Quercetin glycosides (apples, onions, tea, tomatoes)—mutagens and rodent carcinogens

Safrole (nutmeg in apple and pumpkin pies, black pepper)—rodent carcinogen

Kava's article is

here.

Edited March 10, 2005 by Patrick S (log)

[Darcie B]

IMO, the issue is not just the amount of pesticide residue on the foods we eat, but the much larger amounts that are spread on the soils, affecting the quality of the soil itself, and possible runoff issues. Most pesticides are not target-specific; they will kill any bug. This includes many microorganisms in the soil that help plants with nutrient and water uptake, with soil compaction (think earthworms, which are very sensitive to pollution), and other things necessary for plants to grow and thrive. Even though the carrots that I eat may only have trace amounts of man-made petrochemical residues on them that won't adversely affect my health, I am concerned with the long-term effects on soil quality and on nutritional values (concerning fertilizers, not pesticides).

One example I can point to is the use of a particular fertilizer: anhydrous ammonia. Gives lots of nitrogen to plants so it must be good, right? Well, the chemicals other than the nitrogen tend to kill off many soil microorganisms, the soil ends up being compacted and the plants have a harder time getting the nutrients they need. So, ever-larger applications of anhydrous ammonia are needed each season to produce the same results. On some farms I have seen (in North Dakota) the soil looks like photos of the hardpan in Oklahoma during the Depression (severe drought conditions). You can hardly get a shovel into it!

I don't think you can have a discussion about the levels of pesticide residue on plants without considering the larger environmental factors. What good is it to worry about trace amounts of chemicals in your food if you are breathing copious amounts of hydrofluorocarbons from factory/tailpipe emissions? (As an aside, I find it quite ironic that so many "soccer mom" types are buying organic veggies for their kids and picking those veggies up in their Chevrolet Subdivision or Ford Excessive). That being said, I would rather be part of the solution, not the problem, so I buy as much organic as I can afford (and a lot of it tastes better, IMO). Think globally, act locally?

In addition, I think that it is a myth perpetrated by the Monsantos and ADMS that we just couldn't produce enough food w/o synthetic pesticides/herbicides/fertilizers. If we changed our large-scale monocropping method of agriculture, I think it is quite possible to produce enough to feed everyone with, if not total absence of such chemicals, at least vastly reduced quantities of them. Of course, this would also necessitate a huge shift in the consumer habits of the American public which is unlikely to happen.

And don't get me started on how much food we waste in this country...

Edited to add/clarify a couple of points

Edited March 10, 2005 by Darcie B (log)

[Patrick S]

IMO, the issue is not just the amount of pesticide residue on the foods we eat, but the much larger amounts that are spread on the soils, affecting the quality of the soil itself, and possible runoff issues. Most pesticides are not target-specific; they will kill any bug. 

←

That's right.

But you are aware (I assume) that organic does NOT mean, and never has meant, pesticide free? Organic certification allows for the application of a variety of toxic pesticides, so long as they are not synthetic. Pyrethrum, sulpher, copper, neem, sabadilla, rotenone, oil!, Bt bacteria spray, etc all are used in organic farming. Copper and sulpher --and I assume the rest also-- are also toxic to a wide range of non-target organisms. It doesn't matter how toxic to man or how damaging to soil a chemical is -- if it is produced by nature rather than man, it can be used in organic farming. I only bring this up because I am routinely surprised by how widespread is the misconception that organic farmers don't use pesticides, which is simply false. More info on organic pesticides at: Nature's Toxic Tools: The Organic Myth of Pesticide-Free Farming.

In addition, I think that it is a myth perpetrated by the Monsantos and ADMS that we just couldn't produce enough food w/o synthetic pesticides/herbicides/fertilizers.  If we changed our large-scale monocropping method of agriculture, I think it is quite possible to produce enough to feed everyone with, if not total absence of such chemicals, at least vastly reduced quantities of them. Of course, this would also necessitate a huge shift in the consumer habits of the American public which is unlikely to happen.

←

Oh, you could produice enough food without synthetics alright. The problem is that since yields per hectare are on average much lower with organic techniques, you'd need to clear a lot more land to make room for all the farm acres. You could not produce enough food to feed the country using organic agriculture without using a lot more land than is currently used. And of course, though they look nature-y, farms actually (usually) represent a decimation of biodiversity, a replacement of many plant species with just a few. I mean, rolling fields of corn or wheat or whatever is hardly biodiversity.

Edited March 10, 2005 by Patrick S (log)

[corinne]

You said it very eloquently, Darcie. I buy organic in large part so that my children and grandchildren will have a world that can viably produce healthy foods. For more on this, see "Fatal Harvest: The Tragedy of Industrial Agriculture" 2002 by the Foundation for Deep Ecology.

[Patrick S]

I'm not a moderator of course, but I would really be pleased if this thread remained focused with laser-like precision on the issue of pesticides in fruits and vegetables. Its an important issue and one that influences a lot of buying decisions. Not that the other stuff isnt important, but I hope the pesticide issue doesnt get diluted by discussion of other stuff. Just MHO.

[docsconz]

The reason that I am not afraid of synthetic pesticides residues in produce is that the amount of endogenous pesticides in produce -which standard toxicological tests show are just as toxic as synthetic pesticides- is roughly 10,000 times greater than that of synethetic pesticide residues. I don't really see it as worthwhile to spend ~50% more for produce that has only 0.01% less total pesticide content. Lois Gold and Thomas Ames, two of the world's leading toxicologists (Ames is the inventor of the 'Ames test' and the head of the National Toxicology Project), have written a lot on the matter, and managed to completely change my mind. In a 2002 summary of their work, they wrote:

.

←

The creator of the Ames Test is actually Bruce Ames. This may or may not be the same person. This is not meant to criticize the statement, just to set the record straight.

[corinne]

Patrick S., organic farms rely on much greater diversity of crops to maintain optimal soil conditions and keep down pest problems. One example is Natural Systems Agriculture which relies on the ecological benefits of natural ecosystems. Some soy and grain farmers are modeling their fields after the native prairie by featuring a diversity of grains such as soy, corn and sorghum.

[Patrick S]

The creator of the Ames Test is actually Bruce Ames. This may or may not be the same person. This is not meant to criticize the statement, just to set the record straight.

←

My bad. Bruce Ames is the author's correct name (and the Ames test inventor).

[corinne]

I don't see how one could (or should) separate the issue of added synthetic pesticides in conventionally farmed foods from the plethora of other problems with monocultures since the issue at hand is really whether or not it makes sense to buy organic.

[Patrick S]

I don't see how  one could (or should) separate the issue of added synthetic pesticides  in conventionally farmed foods from the plethora of other problems with monocultures since the issue at hand is really whether or not it makes sense to buy organic.

←

I respectfully disagree. The issue at hand was determined by the person who started the thread (Danielle), gave it the title 'Pesticides in Fruits and Vegetables,' and asked for opinions about the issue of 'Pesticides in Fruits and Vegetables.' The issue of 'Pesticides in Fruits and Vegetables' is obvious dissociable from what other pros and cons there are to conventional/organic agriculture.

Edited March 10, 2005 by Patrick S (log)

[Darcie B]

But you are aware (I assume) that organic does NOT mean, and never has meant, pesticide free? Organic certification allows for the use of a variety of toxic pesticides, so long as they are not synthetic.

Yes, I am aware of that, and I am sure that some organic farmers routinely use/abuse these "natural" pesticides. However, I also know that most people who farm/garden organically follow an IPM (Integrated Pest Management) model that limits the use to the minimal amount possible. You reduce the amount of any pesticide/chemical/intervention by practices such as crop rotation, plant selection for resistance to disease, effective plant combinations and so on. No organic farmer I know is thinking just about substituting a "natural" pesticide for a synthetic one. Most people who believe in organic farming (for right or wrong) are idealists, even zealots.

Also, many natural pesticides are target specific. Not all, but many are. Also, many of them are much less toxic than their synthetic counterparts.

Oh, you could produice enough food without synthetics alright. The problem is that since yields per hectare are on average much lower with organic techniques, you'd need to clear a lot more land to make room for all the farm acres. You could not produce enough food to feed the country using organic agriculture without using a lot more land than is currently used. And of course, though they look nature-y, farms actually (usually) represent a decimation of biodiversity, a replacement of many plant species with just a few. I mean, rolling fields of corn or wheat or whatever is hardly biodiversity.

←

That's part of the myth I'm talking about. If you take the same amount of land and use IPM, soil enrichment/replenishment, crop rotation, companion planting, enhance the biodiversity to produce more beneficial insects, etc., and use other practices, you can produce as much or more food per acre. Read the Square Foot Gardener to see how. Of course, that book is on a small scale and on a larger scale the bigger difference is not in the amount of land but in the amount of human labor that will be required to do this. It will take more people, but then again, we don't seem to have a people shortage on this planet...

I certainly don't think such a change will ever happen without some sort of catastrophic catalyst. Humans have for centuries looked to science to solve all sorts of problems, and it may be that science will find a way to overcome the problems that pesticides/herbicides/fertilizers bring. I'm no Luddite, nor am I a granola-munching, leg hair growing crusader with no clue about how the world works (OK I do eat granola. Make it with sorghum...a little cardamom or ginger...yum). I do try to convince people who express an interest in their food sources that there are options that are IMO better, and that they can do something to help the situation using their wallet if by no other means. I don't forsee an all-organic world, but if we can reduce the amounts of many toxins to more manageable levels, the Earth has a tremendous capacity to heal and cleanse itself. I think we should strive to find an equilibrium.

[Patrick S]

Also, many natural pesticides are target specific. Not all, but many are. Also, many of them are much less toxic than their synthetic counterparts.

←

Right, I think we can agree (I think?) that there are target-specific and non-toxic (to humans) pesticides in both the natural and synthetic classes. Now, are you claiming that --as a group-- natural farmer-applied pesticides are more target specific and less toxic to humans at the doses at which they are typically applied? If so, could you provide a reference in support of that claim? If not, then there is still no reason to prefer the natural over the synthetic variety, IMHO.

[Patrick S]

That's part of the myth I'm talking about. If you take the same amount of land and use IPM, soil enrichment/replenishment, crop rotation, companion planting, enhance the biodiversity to produce more beneficial insects, etc., and use other practices, you can produce as much or more food per acre. Read the Square Foot Gardener to see how.

←

Darcie B, later on, and in another thread, we will look at the published field trial data and see just how much 'myth' versus fact there is in the assertion that organic farming has lower yields/hectare on average. But as I said, for right now, in this thread, I want to focus on the topic established by Danielle. I say this just because I don't want you to think I'm rudely ignoring any of the points you made.

[Darcie B]

Last post, I swear. I agree, there are synthetic pesticides/herbicides are have low toxicity to humans. But the natural ones you mentioned above, Pyrethrum, sulpher, copper, neem, sabadilla, rotenone, oil!, Bt bacteria spray, all have extremely low toxicity to humans in the amounts usually applied. You are also correct that I was alluding to low toxicity in humans.

I do not have any data to support a claim that as a group natural pesticides are more target specific, but I was not trying to make that claim. My bad if it sounded like I was.

I was not trying to veer off topic with my first post, I was stating my point that I find it quite difficult to separate the amount of pesticide residue in produce from the larger pesticide application issues.

Edit to add: One last thing, I think we can all find data to support any claims. It is worthwhile to see who financed/supported the research that makes the claims. Hardly any research is unbiased, usually it starts with the results desired and works it way to them.

Edited March 10, 2005 by Darcie B (log)

[=Mark]

Interesting in that it was announced earlier this week that human life expectancy in the US has increased again. The obvious inference is that chemicals and pesticides in food are good for us...