Why You Probably Don't Know That Pesticides Have Changed

Note how grape pesticide use has shifted almost entirely to the EPA
categories IV (practically non-toxic), and III (slightly toxic)

In my last post I gave an example of how much safer pesticides have become over time.  That would come as news to most people because they have a negative, out-dated and stereotyped image of pesticides.  I think there are three reasons for this:

1. Very few people have any role in the control of agricultural pests
2. There is a widespread, convenient fiction that organic farming means no pesticides
3. The unlikely "team" that has driven change in pesticides has, for various reasons, failed to communicate their success

1. Who Controls Crop Pests? Probably Not You

If you live in the rich world and are involved in crop production, you are part of a tiny minority of highly efficient producers. Because of this, there are very few people who have observed the changes in the nature of pesticides over time or who are familiar with the current portfolio of options.  I follow a number of farm press publications and blogs, and the discussion of pesticides there is completely different than in any mainstream source. Those who choose to play a role as commentators on agriculture should take the time to be well informed on modern pesticide use and safety.

2. The Convenient, "No Pesticides" Fiction

The production of organic crops definitely involves the use of pesticides. In many cases it requires more frequent applications and/or higher use-rates per acre than for conventional. The pesticides organic farmers are allowed to use come from a list deemed by committee as being "natural," but they are still pesticides and they are not necessarily safer for us or for the environment than options available to other farmers. Natural does not automatically mean safe, that is why natural options also have to go through EPA registration. There are quite a few pesticides that are widely used by both kinds of farmers.  These facts are not broadly understood.

Most consumers have the impression that choosing organic means avoiding pesticides, and the broader organic marketing chain and advocacy wing is often happy to promote this misconception.  At a farmer's market one often sees signs saying, "no sprays," or "pesticide free," statements that are rarely true. Various promoters and marketers of organic often argue that consumers should choose organic "to avoid pesticide residues" even though choosing organic actually means you know less about what residues are likely to be present because none of our residue monitoring efforts look for some of the materials most commonly sprayed on organic crops (e.g. copper fungicides, biocontrol agents, Bt toxins...).

At a mainstream grocery store I recently saw a sign over the organic produce display saying "grown without chemical fertilizers or pesticides," as if there were some category of physical matter which isn't a chemical.  Even defenders GMO crops are often guilty of saying that a Bt crop "reduces the use of pesticides" when, in fact, it is simply a different means of delivering a pesticide - another very safe one, but still a pesticide. The consumer needs to know if there is any pesticide residue of concern on a given food. Year after year, an extensive USDA survey of pesticide residues on food in commercial channels  show levels that are too low to be of concern. Consumers have no reason to hesitate to consume the domestic or imported conventional food supply in the US. Unfortunately this analysis is routinely distorted by the Environmental Working Group to promote organic as a means of "avoiding pesticide residues."  Recent data from Canada shows that there are frequently pesticide residues on organic produce there.  Again, the question is whether the levels are high enough to matter.

3. The "Team Effort" You Never Hear About That Made Pesticides Safer

As a 37-year participant in various parts of the process of changing the nature of pesticides, I've seen an unlikely collection of entities, each of which should take some of the credit for the progress that has been made.  For each I'll briefly describe their contribution(s) and also speculate on why you probably don't know about it or appreciate it.

• The Environmental Movement:  becoming visible after the publication of Rachel Carson's "Silent Spring" in 1962, a broad coalition of NGOs, politicians and academics drove the awareness and impetus for the creation of regulatory bodies such as the EPA (est. 1970) which began to regulate pesticides. In a variety of ways these groups have continued to be an important voice that puts pressure on regulators to deal with additional issues as they arise through advances in the sciences of human and environmental toxicology. However, you won't hear these groups talking about how much things have improved. They tend to focus on the next issue rather than on past progress, even if they could take some real credit along with the rest of the "team." 

• The Major AgroChemical Companies:  These players have been investing hundreds of billions of dollars over decades to discover, evaluate, and commercialize new pesticide options.  Their search has been for products that work better, which are more selective, and which can meet ever more sophisticated health and environmental standards. Without this investment, between pest resistance development, new pests and regulatory constraints, farmers would never have been able to accomplish the sort of productivity gains that have been seen. These players are actually constrained by the EPA from talking about new products as being safer than the older ones. They also usually have a mixed portfolio of newer and older products.  Besides, in an anti-business climate their messaging is typically ignored.

• Government Regulators:  If you step back and look at what agencies like the US EPA have accomplished over the decades, it is rather impressive.  On the whole, the EPA has done its job in a way that is science-based and free from excessive political influence.  As is probably the fate of any such regulator, the various "sides" on issues are all going to be unhappy with something about your decisions or bureaucratic procedures.  Honestly, the EPA does not seem to have the skill or orientation for public promotion of what they have achieved (although this summary is pretty good).  In any case the political Right tends to want to get rid of the agency, and the Progressive Left seems to think that they have all been "bought-off."  I have some direct experience with EPA staffers and a window on their process through friends who serve on advisory panels. This system isn't perfect, but it deserves a great deal more respect than it gets.

• Academics and Other Public Research Institutions (University, USDA, EPA, Research Institutes...):  Public, industry, and grower groups have funded basic and applied research  critical to the progress that has been made on understanding toxicology, environmental fate, modes of action, and efficacy of pesticides.  Many chemical leads have come from basic work on natural products. Most biological control ideas emerged from this sector. The integration of pesticides with the many other means of pest control was often researched here. You may not have heard much about this because scientific publications are not designed for the public, but there are some USDA and University publications designed for more general readership. 

• The Public and Private Entities Closest To Farmers:  The farming community is provided with applied research results, technical advice, and logistical support by a range of groups such as State and County Extension Agents, AgChem Retailers, Crop Consultants, experts supported by Grower Organizations and sometimes major purchasers of their crops (other government and university experts overlap in this area as well).  The evaluation and integration of new pest control methods of all types and combinations is greatly aided by this group. They are highly focused on their grower base, so most people would never hear about them.

• Farmers Themselves:  The role of farmers is perhaps the most important because they are the ones who integrate ever changing pests, climate, regulations and pest control options. They also absorb the associated economic risk. The farmers are the ones for whom pests are an ever-present reality. They certainly have economic incentive to limit their pest-related losses, but also economic incentive to do so in a cost effective way. They care about the environment and human health as much as anyone.  Fortunately they have a stream of new options to help them pursue those goals and the willingness to innovate to make them work.  Instead of getting any appreciation for these efforts, farmers are routinely demonized by critics who have not bothered to get an in-depth understanding of their challenges or of the tools they actually use.

Consumers don't have to understand how much pesticides have changed or why in order to get the benefits that come with increased productivity and safety.  However, it wouldn't hurt them to know about this so that they could enjoy the food available to them.

Chemical Free Egg Image from Bob Doran

You are welcome to comment here and/or to email me at savage.sd@gmail.com

An Example Of How Much Pesticides Have Changed

The pesticides that farmers use to protect their crops have changed a great deal over the last few decades.  While improvement is something we expect from technologies as diverse as pharmaceuticals to electronics, few people are aware of the positive developments in the chemicals used for crop protection.  Dramatic change began with the establishment of the EPA in 1970 which led to the elimination of many problematic, old pesticides.  Also, there has been a steady stream of new product introductions with both safety and efficacy advantages.

To document how pesticides have changed, I decided to download historical information for one of my favorite crops - premium wine grapes. California has had mandatory pesticide use-reporting in place since 1990. The resulting data can provide a window on at least 22 years of this evolution. I chose 5 counties that would represent much of the premium acreage in both the North Coast (Napa, Sonoma, Mendocino - 121,700 acres in 2011) and the Central Coast (Monterey, Santa Barbara - 62,288 acres in 2011).

Grapes have a wide range of pests, including several kinds of insects, mites, nematodes, fungal diseases, and viruses, the vectors of which require control. Weeds are also an issue. Because traditional varieties are highly valued, conventional plant breeding is not an alternative to get around these pest problems. As with other crops, the management of these pests involves much more than just pesticides.  Even so, pesticides will always be necessary tools. Pest control in grapes is important for both yield and quality, and in some cases for the long-term survival of plantings that are very expensive to establish.  As with other crops, control of grape pests also preserves efficient use of other resources such as uniquely suitable land and scarce water, as well as expensive nutrients, fuel and labor.

Fortunately, for reasons I will describe in a subsequent post, the pesticides available to farmers today are both effective and relatively safe - much safer than what they were a few decades ago, and much safer than most people imagine.

The Overall Use-Trend

As you can see in the graph above, overall, pesticide use on grapes (in terms of pounds of active ingredient) has been declining since 1995.  The numbers; however, are rather large compared to other crops - 40 to 100 pounds of active ingredient per acre per year (The recent controversy about pesticide use on Maize nurseries in Kauai was over a 1.9 lb/acre/year use pattern). There is one simple reason that these numbers are so large - sulfur.

There is a fungal disease called Grape Powdery Mildew which infects even under California's dry summer conditions.  Elemental sulfur, applied either as a dust or as a wettable spray, has been the mainstay for control of that disease for centuries. As you can see in the graph to the right, sulfur accounts for most of the very high pesticide load, particularly in the 90s. Sulfur is considered a "natural product" and is thus approved for organic.  In fact it is almost all that an organic grower can use for this disease. It has to be applied frequently and at very high rates. Sulfur is considered relatively safe, but it is a skin and eye irritant which is problematic for vineyard workers.  I've spent lots of time working in vineyards and the sulfur makes that unpleasant. The tendency of the dust to drift is annoying for neighbors of vineyards.

Notice that after 2000, the amount of "other foliar applied" pesticide increases.  Much of this represents modern options for mildew control that have allowed growers to dramatically reduce their overall use of sulfur.



The Non-Sulfur Trends

Taking a closer look at everything that wasn't sulfur, we see that the pounds per acre of other foliar pesticides more than doubled and the soil-applied pounds per acre dropped 4x between 2000 and 2011 (the latest year of data available).  But of course when it comes to pesticides, "pounds" isn't really a very informative measure. Pesticides differ dramatically from one another, particularly with regard to acute toxicity.




The EPA classifies pesticides into four categories based on their toxicity (see an explanation of how this is measured at the end of the post).  Their acute oral toxicity is a major part of that classification:

1. Category I, "highly toxic" materials, Oral ALD50 less than 50 mg/kg                                       
2. Category II, "moderately toxic" materials, Oral ALD50 50 to 500 mg/kg
3. Category III, "slightly toxic" materials, Oral ALD50 500 to 5000 mg/kg
4. Category IV, "practically non-toxic" materials, Oral ALD50 greater than 5000 mg/kg

What About Most People's Image of Pesticides?

When most people hear "pesticide" their mental image is something like the old, highly toxic, organophosphate (OP) insecticides.  The graph at the right looks specifically at what percent of all the pesticide applications (sprays, not pounds) were made with these sorts of products. Note that the classic, Category I OPs were never more than 6% of the sprays and have been under 1% for the last 10 years of data. Even the moderately toxic category II OPs have never represented much of the total spray load. In the last few years they have declined to an all time low.  These products make up an even smaller fraction of the total pounds of pesticides applied (under one percent for all 22 years).  Thus, what most people imagine when they hear "pesticide" is actually a very rare type of product in terms of actual use.

The Changing Product Mix Used on Grapes By EPA Category

The graph above tracks the proportion of non-sulfur pesticides used on these grapes by EPA category.  Even when all the Category I pesticides are included, they have never made up more than a tiny percentage of what is sprayed on grapes. If we had data like this going back to the 60s or 70s there might have been more - but highly toxic products have not been used much in this or most other crops for a long time.

Category II pesticides were a reasonably good part of the mix until recently.  The EPA calls these "Moderately Toxic."  That may sound scary, but many familiar food and beverage chemicals fall into this toxicity range including capsaicin in hot peppers (140mg/kg) and caffeine in coffee (161mg/kg).  Several products used on organic grapes also fall into this category.  Even so, this has been a declining category over time.

The EPA category III products are called "slightly toxic." Very familiar natural products like citric acid, acetic acid, vanillin or even table salt fall in this range. There has been some increase in the use of products in this category.

The category IV products are classified as "practically non-toxic" and this has been the area of most rapid growth since the mid 1990s.  Many of the products that have displaced sulfur use fall into this category.  Many of the products that have replaced the old OPs fall into this category. These relatively benign materials are really the face of modern pesticides - not what most people imagine.

The category II, III and IV products include a mix of synthetic products and natural products which could qualify for organic.  The total area of organic grapes is small, but in this and other crops there is a substantial overlap between the pesticides used in conventional and organic.

Another Way To Look At The Data

The EPA categories are rather broad, so another way to look at this is to "weight" the amounts based on their relative oral toxicity.  In the graph to the right I have taken the foliar, non-sulfur numbers and multiplied them all by the value 500/Oral ALD50.  500mg/kg is the dividing line between "slightly" and "moderately" toxic in the EPA categories.  Thus a product with a toxicity of 4000 mg/kg is counted as 1/8th of its weight in pounds.  A product with a toxicity of 40mg/kg is counted as 12.5 times its weight in pounds.

From this approach we see that even though almost three times as many pounds of foliar applied, non-sulfur pesticides are being used on grapes in recent years, there has really been no increase in the overall "toxic load" involved.

In the 22 years covered by this data set, there have been some dramatic changes in the nature of pesticides used. The crop and product in this case may be quite special (and delicious), but the trend is not unique to wine grapes.  We would see a similar change in most crops.  This sort of change didn't happen by accident.  It represents a great deal of work by a diverse collection of players in the public and private sphere. I'll go into that in detail in the next post in this series.

You are welcome to comment here and/or to email me at savage.sd@gmail.com

Napa vineyard image from Almonroth via Wikimedia Commons
All graphs mine based on CalPIP data correlated with acreage data from California County Ag Commissioners Reports

Primer on the Measurement of Acute Toxicity

There are many dimensions of toxicity, but the most basic is how toxic something is when consumed.  This is what would be of concern for pesticide residues.  This is called Acute Oral Toxicity and it is determined by feeding different amounts of a chemical to a population of rats or mice.  The dose relative to the animal's body weight that kills 50% of the subjects getting that dose is called the LD50.  It is expressed as milligrams of chemical per kilogram of body weight.  For these numbers the larger the value, the less toxic the compound.    For reference, table salt has an oral ALD50 of 3,000 mg/kg.  For a 120 pound (54 kg) person that would mean a toxic dose of 163 grams which is about 1/4 of a normal, 1 pound canister of salt.  For that same person, the toxic dose of caffeine (oral ALD50 191 mg/kg) would be 10.4 grams - what one would get from 32 servings of nice coffee at Starbucks.  In both cases, the salt or coffee would need to be consumed very quickly to achieve that dose.  Some of the most toxic insecticides ever used had oral ALD50s in the range of 5-10 mg/kg.  Most pesticides today have oral ALD50s of more than 5,000 mg/kg (Category IV) and are less toxic than table salt, vinegar, citric acid, vanillin and many other familiar food ingredients.

Five Ways Farmers Control Pests Other Than With Pesticides

There are many pests in the world which attack plants or compete with them for the resources they need to grow.  This is true for plants growing in natural stands, but also for the plants that people grow as crops.  If pests are left unchecked, crop productivity is compromised. Without good pest control, it would take a lot more land to feed humanity - land we simply don't have.  Pest damage can also compromise the storage or shelf-life of foods leading to more wasteful inefficiencies.  Pests can also make foods dangerous through the production of mycotoxins (see contaminated corn below)

Corn infected with Aspergillus flavus can be contaminated
with one of the more toxic and carcinogenic chemicals known

One way that farmers prevent these problems is with the use of pesticides, and this is true in both organic and conventional production systems.   However; farmers also control pests in many ways other than using pesticides.  These tools and strategies differ based on the crop and the geography where it is grown, but they include at least the following five categories:

1. Avoiding the pest
2. Finding genetic resistance
3. Modifying the climate
4. Disrupting the pest's life cycle
5. Fostering beneficial organisms 

1. Avoiding The Pest

Not all pests occur in all places.  Pests like insects and diseases have co-evolved with the plant species that they are able to attack, often in the geography where the crop was first domesticated.  Sometimes by moving the crop to a new location, the pest can be avoided.  This happened several times with coffee rust and with potato late blight when that crop was first brought to Europe from S. America.  Eventually the pest tends to catch up, and with the intensity of modern travel, pest redistribution is inevitable.  The more stable way to avoid a pest is to grow the crop in a new climate that does not favor the pest.  When fruit and vegetable crops are grown in Mediterranean climates (e.g. California, Italy, Spain...) where there is little or no rain in the growing season, many diseases are avoided.  This of course requires irrigation, but if that is done with subsurface drip, weed growth is also largely avoided (see below).

Another good example is the potato industry which is in the San Louis Valley of Colorado surrounded by high mountains.  This isolates the crop from aphids and the viruses they spread and is particularly good for seed potato production.

2.  Finding Genetic Resistance

Wheat stem rust is a potentially devastating disease that was successfully
controlled using genetic resistance for several decades

One of the reasons for a concerted effort to maintain extensive seed banks is to maintain the genetic diversity in a crop which may include resistance traits to various pests.  For instance, when the resistance to wheat stem rust was finally overcome by the UG99 strain of that fungus, wheat breeders went to the seed banks to find a new resistance gene and have been cooperating internationally to get that trait bred into the myriad types of wheat grown around the world.  There are also often genetic solutions for soil-borne pests which involve grafting the desirable type of a fruit or vegetable onto a rootstock that provides resistance.  This is most commonly used for perennial crops, but in recent times this sort of grafting for genetic resistance is also being used with tomatoes, cucumbers and even eggplants.

Genetic engineering provides a means of using genetic pest resistance in situations where ordinary breeding for such a trait is either impossible or far too slow.  For instance there is a gene for resistance to a bacterial disease of peppers which has been moved to tomatoes making them resistant to that same bacterium.  Potatoes are difficult to breed, but by transferring a gene from wild potatoes from the Andes, disease resistance has been moved into modern, commercial-type potatoes (see below).

Potatoes genetically engineered to resist late blight
using a gene from their wild relatives

Breeding resistance to coffee rust is possible, but doing that with conventional breeding methods will not be fast enough to help the small-holder coffee farmers whose way of life is now threatened by that disease.  Unfortunately, the rich world part of the coffee industry has elected not to use genetic engineering to speed up that process.

3.  Modifying The Climate

Wine grape growers often use trellising methods and removal of lower leaves to change the microclimate where the grape clusters are developing.  This helps to prevent a fungal disease called "Botrytis bunch rot."   There are a whole range of growing practices called "protected culture" that range from a simple rain shield to a passive greenhouse to a high-tech greenhouse with complete climate control.  These measures provide relief from certain diseases that would otherwise be fostered by rain.  In some cases the system excludes insect pests all together (see below).  Although this approach is too capital-intensive for many crops, it is very effective for high value vegetable and fruit crops and this is a rapidly growing segment of agriculture around the world.

Tomatoes grown without soil and protected from insect pests

4.  Disrupting The Pest's Life Cycle

Perhaps the most common way that pests are controlled in annual crops is through the use of crop rotation.  For instance, corn is typically rotated with soybeans throughout much of the midwestern US.  This prevents population increases of certain pests because every other year certain pests don't have a suitable host available.  For potatoes it is often necessary to have several seasons of other crops planted between each potato crop, otherwise pests become too damaging.  Another way that insect pests can be controlled is through an approach called Mating Disruption.

Synthetic versions of the insect's mating hormones are placed throughout a field or orchard so that the males can't detect the gradient of that hormone which guides them to females.

In certain cases it is possible to release large numbers of male insects which have been intentionally raised and sterilized.  These males then out-compete the wild ones to mate with the females and so very few offspring are generated within the population.  For pests that are quite specific to a given crop and which don't succeed on other crops or weeds, it is possible to organize a time of year when no examples of that crop are growing throughout a given geographical area.  The crop-free period results in a crash in the pest population.

5.  Fostering Beneficial Organisms

Even pests have pests, and often there is a way to encourage those "natural enemies" sufficiently to keep crop pest populations at tolerable levels.  For example, the cottony cushion scale was once a big problem in the California citrus industry, but the problem was greatly reduced once a natural predator of the scale called the Vidalea Beetle was introduced into the state.

Cottony Cushion Scale

Vedalia beetle

The grape leafhopper can be a very damaging pest, but when growers plant wild blackberry vines near their vineyards, they encourage the build-up of a certain kind of parasitic wasp which attacks the blackberry leafhopper species in addition to the grape leafhopper.  This can keep the grape leafhopper numbers sufficiently low to make pesticidal control unnecessary.  Some insect predators or parasitoids are raised commercially for release on farms.  Some diseases and nematodes are controlled by applying biocontrol agents such as bacteria or fungi which act as hyperparasites.   When potatoes were genetically engineered with a Bt protein to resist the Colorado Potato Beetle, farmers noted that secondary pests were no longer a problem because the natural enemies were no longer being killed by broader spectrum insecticides.  Unfortunately, when fast food companies chose to use their leverage to end the growing of Bt potatoes, a resurgence of these secondary pests was one of the consequences.

Pest control in agriculture is a multi-dimensional effort, and pesticides are just one of the important tools, procedures and choices that farmers employ.  Some of these tools have been in use for a very long time and some are new.  With climate change, the control of pests will become even more difficult. As global population grows and standards of living increase, it will be even more important for farmers to avoid the sort of losses and food waste than can be caused by pests.  Fortunately the tool box available is diverse and constantly improving.

You are welcome to comment here and/or to email me at savage.sd@gmail.com


Image of corn with aflatoxin-producing Aspergillus flavus infection from Iowa State University IPM
Drip irrigated tomato image from safs.ucdavis.edu
Wheat stem rust images from USDA-ARS
Grafted tomato image from Wikimedia Commons
Engineered blight resistant potato image from The Sainsbury Laboratory
Vertically trellised grapevines with leaf removal image from Extension.org
High tech tomato greenhouse image from Wikimedia
Mating disruption graphic from WSU Tree Fruit Research and Extension Center
Cottony Cushion Scale image from Invasive.org
Vedalia beetle image from Wikipedia

What Trans-fats Should Teach Us About The Pitfalls of Food Labeling

On November 7th, the FDA announced that it will remove partially hydrogenated oils from the GRAS list (Generally Regarded As Safe).  These oils contain trans-fats.  The agency has concluded that the voluntary replacement of such fats has not progressed far enough to adequately protect Americans from the negative cardiac health dangers that they pose. This is a good, if seriously belated, decision. It is worth looking back at the history of this food ingredient to see how we came to be eating trans-fats in the first place and what role food labeling (mandatory and marketing) played in that story.

The Origins Of The Low Fat Diet Push

In the 1960s, medical and public health officials became alarmed at the high rates of cardiac-related sickness and deaths in the American population.  A correlation was found with high-fat diets and soon there was widespread advice to avoid two particular categories of fat – cholesterol and saturated fats. In retrospect this was a severe over-simplification and a demonstration that correlation does not mean causation. Unfortunately a “low fat diet” caught on as “the answer” with the public and with food marketers. More and more food products entered the market with voluntary labels such as “Low Fat,” “Cholesterol-Free,” “Zero Fat,” and “Low in Saturated Fat." This trend didn’t turn out to be health-promoting. In many foods with lowered fat content, additional sugar was added to make it more palatable. For many years, eggs were demonized because of their cholesterol content when in fact they are an excellent and reasonably priced protein source. All the decades of focus on avoiding fats or certain fats did nothing to stem the obesity epidemic, and reductions we do see in heart attacks and strokes are thus probably linked to other factors.

How Misguided Food Labeling Led To Our Consumption Of Trans-Fats

When the negative focus on fats began, animal fats were major sources of cholesterol and saturated fat in our diets (butter, lard, bacon fat).  Tropical oils, such as palm and coconut, were additional sources of saturated fats. The pressure to find alternatives to these oils coincided with an increasingly abundant supply of oil from the domestic soybean crop.  Soybeans were a minor US crop before World War II, but by the 1970s they had become the major source of protein for animal feeds. A soybean contains ~20% oil and so it rapidly became the lowest-cost oil in the American food supply. 

Soy's Limitations

There are, however, issues with soybean oil. It has properties that make it unsuitable as a simple substitute for animal and tropical fats in various applications (if you are interested there is a short course on the chemistry of oils and fats at the end of this post). It couldn’t be used to make a substitute for stick butter because it was liquid at room temperature.  Soybean oil was also poorly suited for deep fat frying applications because it didn’t have the necessary “fry life” to fit in the burgeoning fast-food industry of that time.  After a relatively short period of high temperature cooking, it would develop off-tastes.  In other products it tended to turn rancid faster that other alternatives.

Food scientists had earlier developed “partial hydrogenation," a process through which most of those issues could be addressed (hydrogenated oils began to be sold early in the 20th century).  Hydrogenation allowed food companies to turn soybean oil into margarine and then to market it against butter as a perceived healthier option.  In the anti-fat environment, oil processors could sell partially hydrogenated oil to the fast food industry, which then promoted the supposed health advantages of their switch to “vegetable oil.”  The converted oils were also extensively marketed in products with the marketing claim, “No Tropical Oils.”  This was somewhat of an intended health claim, and also a means of competing with the low cost imported oils from palm and coconut. The hydrogenated oil also had some unique properties which were particularly useful for certain baked goods.

Between low cost and these positive-sounding messages, hydrogenated soybean oil found its way into a host of foods in the US diet. When mandatory nutrient content labeling was established in 1990, Congress failed to fund the education component envisioned in the bill.  Thus, the official "back label" only served to further propel the sales of various fat-avoidance products and trans-fats, and did nothing to stem the disinformation on the front, marketing-oriented labels.

Early on,  the substitutions being made by these commercial entities were done with confidence that they were a good thing. Unfortunately, that was not true. 

The Solution Becomes The Problem

Unfortunately, during the hydrogenation process “trans” versions of certain fats are generated.  The term trans has to do with a specific chemical configuration in the fat molecule.  In most oils and fats that configuration is generally of the “cis” configuration and rarely the “trans” (again, more details below).  It was this subtle difference which was later found to change the way that these fats functioned in our bodies.  Most of the fat we eat is simply converted to energy, but some is incorporated in the membranes that surround each of our cells.  Some of the fat can also end up in plaque deposited in our veins and arteries.  The health issues for trans-fats played out importantly in those functions.

In retrospect, Americans would have been much better served in terms of flavor and health if they had stuck with the animal fats and tropical oils instead of hydrogenated oils (French fries have never been as delicious as when they were cooked in beef tallow!)

Eventually, evidence began to emerge that trans-fats were problematic for human health when consumed in larger quantities. This only very slowly built up to the point where regulators raised red flags and began to require trans-fat labeling in 2006.  Many food companies shifted away from trans-fats and to market foods as having "zero transfat." Now the FDA is finally moving to fully eliminate an undesirable ingredient which became common because of earlier labeling trends.

What Should We Learn From This?

So, did we learn from the low fat marketing experience?  Seemingly not much.  Instead we have continued down the path of magical thinking about food.  We go through fad after fad about what single bad actor ingredient to avoid or what magical good component to eat, somehow believing that these simplistic formulas can put us on the path to health.  The press, various celebrities and "experts" are often guilty of over-selling such ideas as they emerge incompletely formed from the fields of nutrition or medicine. Well-meaning or simply opportunistic food marketers are then more than willing to follow or even promote each fad.  I call that "the marketing of non-existance." We continue to be sold new non-existence options such as  “Low Carb,” “no High Fructose Corn Syrup,” “Gluten-Free,” and “non-GMO.” These are dietary strategies based on the mindset that foods are something to be feared or at least viewed with suspicion.  

These fads distract us from the fundamental healthy diet principles of moderation and diversity.  They distract us from the fact that the most dramatic way that most Americans could improve their health prospects would be to consume more fruits and vegetables.  Perhaps its time to start buying what we eat for what it is as a whole food, not for what it is not.

You are welcome to comment here and/or to email me at savage.sd@gmail.com.  I tweet about new posts @grapedoc

A Short Course About Oils And Fats

Fats and oils are similar with fats being solids at room temperature and oils being liquid.  In both cases they consist of triglycerides - three "fatty acids" connected to a glycerol backbone.

What makes the various fats and oils different from one another is what kind of fatty acids they contain.Fatty   acids are chains of carbon atoms with a polar carbonyl group at one end.  They differ in the length of the chain and in how many double bonds there are between the carbons.   

As shown above, the dominant fatty acid in animal fats is stearic acid with 18 carbons and no double bonds (saturated).  Oleic acid which is a major component of olive oil or modern Canola and Sunflower oil also has 18 carbons, but has one double bond (mono-unsaturated).  Linolenic acid was one of the problematic components of soybean oil which needed to be fixed by partial hydrogenation.  It has 18 carbons and three double bonds (poly-unsaturated).   "Tropical oils" are generally shorter chained - Palm oil has mostly 14 carbon amino acids and coconut oil has mostly chains of 12 carbons.

The cis- and trans- fats differ in the orientation of the hydrogen atoms (white) attached to the carbon atoms (black) that are connected by a double bond.  The normal cis- configuration has both hydrogens on the same side of the chain.  The trans- configuration has the hydrogens on the opposite side of the chain and this gives the fatty acid a different bend and influences its fluid properties when it is part of a membrane.  There are some natural trans-fats, particularly in meat and milk from ruminants because rumen bacteria convert unsaturated fats to saturated forms, going through some trans- intermediates along the way.  There are actually health benefits associated with the production of Conjugated Linoleic Acid (CLA) in this process.

My Comment To The USDA In Support Of Deregulation Of The Arctic Apple

I would like to express my strong support for the deregulation of the non-browning apples developed by Okanagan Specialty Fruits, Inc.  As a consumer I would very much like to have the choice of buying apples which would maintain their appearance, taste and nutrient content longer after being cut.  As a long-term agricultural scientist I completely agree with the USDA's assessment that these apples are not any sort of plant pest. 

Since apples are not grown from seed, but rather propagated by grafting and other clonal means, any minor cross-pollination between blocks of modified and non-modified apples is functionally a non-issue.  Different varieties of apples are routinely planted side-by-side with no concerns about "contamination." 

I know that the issue of organic certification has been raised, but there is no rational reason why that should be a concern.  The precedent for the unintentional presence of unapproved pesticide residues on organic fruit is that even if it occurs it does not effect the certification of the farm in question.  If that is the logic for residues that may be consumed, then the logic should prevail for the presence a few, down-regulated genes in a small number of cells in the germ of a seed.  This is particularly true because the seed is not consumed (apple seeds are cyanogenic so it wouldn't even be a good idea to eat them if someone wanted to).

Consumers should get to decide whether they are interested in this trait.  They will have that choice because it will be marketed explicitly as an improvement via genetic engineering.  This is an optional trait, but it is a key test of whether our regulatory system and commercial channels will stick with a science-based approach or yield to activist political and brand pressure tactics.  There are other traits coming such as resistance to citrus greening which may be critical for the survival of a crop industry, and what happens with the Arctic Apple could effect the chances of that solution becoming available to farmers.

I realize that there has been some opposition to the Arctic Apple from apple industry organizations - not because of any plant pest or consumer safety concerns, but because of "brand risk."  I think the broader apple industry would do well to remember that for a long time they tried to build an "apple brand" based on an intentionally narrow group of varieties - Red Delicious being the primary standard based on color and shape more than on flavor.  When that strategy collapsed in the wake of the "Alar Scare," innovative growers branched out and began offering consumers a wide range of varieties with different appearance and flavor.  It turned out to be an extremely healthy shift that strengthened the "apple brand" among consumers.  Adding non-browning options for consumers to choose is a continuation of that successful marketing strategy.  

You are welcome to comment here and/or to email me at savage.sd@gmail.com.  I tweet about new posts @grapdoc

Resources:

Okanagan Specialty Fruit Website

Description of the regulatory status of the Arctic Apples at this point in time 

Link to the Regulations.gov site where you can comment

The People Side Of GMO Crops: Part I

As with any new technology, the development and commercialization of biotech crops is a story about people.  Its a story about people with ideas and vision; people who did hard and creative work; people who took career or business risks, and people who integrated this new technology into the complex business of farming.  By various artifacts of my educational and career path, I've been in a position to know many of these people as friends and colleagues over the last 36 years.  Their story is important, but it tends to get lost in much of the conversation about biotech crops.

Many narratives about "GMOs" leave out the people side, presenting it instead as some faceless, monolithic phenomenon devoid of human inspiration, intention and influence. Thats not how it happened.  Other narratives about "GMOs" demonize those who made biotech crops a reality. Such portrayals are neither fair or accurate.  The real stories of these people matter, because trust in a technology is greatly influenced by what people believe about those behind it.

That is why I'd like to write about what I have observed about these real and trust-worthypeople over the years. I'll start with the period 1976-1982.

It Started On "The Farm"

Stanford has the nickname, "the farm" but its no Ag School!

I first heard of genetic engineering in 1976 while a senior at Stanford University in a graduate level biochemistry class. The professors lecturing on the exciting new science of molecular biology were Paul Berg, Stanley Cohen and Herbert Boyer.  These basic researchers were doing purely lab work with no commercial motivation, but in the process, they ended up inventing "recombinant DNA technology." At the point of my introduction, the science was still young (key experiments started in 1971).  The Stanford researchers discovered the enzymatic "tools" to cut and paste genes and other key pieces of DNA.  From the beginning it was clear that these discoveries had a huge range of potential applications in basic research, medicine, pharmaceuticals, bio-materials and bio-processing.  It also had potential for agriculture. It was an exciting time, but it took many years for all this to unfold in practical applications.  Berg later received the Nobel Prize for his work and the patents that came from the work of Cohen and Boyer became some of the most widely licensed in history (they became a huge source of research dollars for Stanford).  Genetic engineering, GMO if you will, started in the labs of people who were focused on academic research.

Safety First

The setting for the first conference on biotech safety

It is significant to note that these and other early genetic engineering researchers took special precautions from the very beginning to make sure that they were not creating something in their labs which could be dangerous.  Paul Berg was instrumental in organizing the 1975 Asilomar Conference, a gathering of scientists designed to carefully consider all the ramifications of this new science of "genetic engineering." The outcome of that conference helped guide the NIH (National Institutes of Health) to set guidelines for lab safety regarding biotechnology.  The original rules were severely restrictive, and were only relaxed a bit after much experience and increased understanding.  I'd be interested whether any of my readers are aware of other technologies for which such precautions were taken at such an early a stage?  This standard of thoughtfully trying to anticipate any risks or issues carried forward as the science developed.

Off To Davis To Become An Aggie

The iconic water tower at Davis

Many biology students from my generation went on to pursue the various applications of genetic engineering.  Although I was fascinated by what I had learned about this basic science, I was interested in a much more applied science called Plant Pathology - the study of diseases of plants.  So, in 1977 I started graduate work at the University of California, Davis - an actual ag school.  My research was field oriented and I got my first exposure to farming and farmers.  However, one aspect of my project involved lab work, and the particular equipment I needed was in the adjoining labs of Dr. Robert Shepherd and Dr. Tsune Kosuge.  Both labs worked on topics which were of great importance to the brand new science of plant genetic engineering.  So, my education about biotech continued.

My lab-mates at Davis were pursing very basic research needed to answer two key questions:  "How can we get new genes into the nucleus of a plant cell?" and "How will we get those genes to express" - to be turned on in the cells of the plant as desired?  

A Virus Disease of...Cauliflower?

My little bit of bench space was in Shepherd's lab which worked on virus diseases including Turnip Mosaic and Garlic Mosaic Virus (the smell of the later often permeated the lab as samples were ground up for analysis).  The lab was also one of a few around the world that worked on CaMV (Cauliflower Mosaic Virus).  That is a rather minor disease, but it was of interest because it is a DNA plant virus while most plant viruses are RNA viruses.  Several of my lab mates were "sequencing" that virus, meaning that they were figuring out the pattern of A,T,G and C bases in its genetic code.  The methods they used are humorously crude by modern standards and it took them more than a year to get the sequence - something that would probably take less than a day with modern equipment.  In any case, there was a hope that once the genetic code of CaMV was understood, it might be possible to use that virus as a way to move a new, desired gene into a plant.  After all, the virus manages to do that for its own purposes.  That goal never materialized because the virus protein capsule was too small to "package" a useful gene, but CaMV turned out to be important for a different reason.

You can't fit much DNA in these little virus particles

A gene "promoter" is a part of the DNA sequence that sits in front of a gene and tells tells cells how and when to express that gene - usually meaning to have the cell make the protein for which it codes.  It turned out that a promoter from CaMV called "35S" eventually became the most widely used promoter for transgenic crops of the first generation - both in research and commercial use. At the time, however, the team in the Shepherd lab was just doing basic research, mainly with the hope of getting out some good publications.  35S was actually first described and patented by a group at Rockefeller University.   

Nature's Genetic Engineer

Graphic about how Agrobacterium works, now that we understand 

The neighboring lab (Dr. Kosuge's) also had equipment I needed.  The graduate students, technicians and post-docs there all worked on a soil microbe called Agrobacterium tumifaciens which causes a disease of many plants called "Crown Gall."  Agrobacterium is nature's "genetic engineer."  When it gets into a plant injury it is able to inject a circular piece of its DNA (a plasmid) into the exposed cells.  Then, the genes from the bacterium start functioning in the plant.  The bacterium "engineers" the plant to provide itself with both a protective home and an exclusive food supply based on two unique amino acids only it can use.

A crown gall on a grapevine "engineered" by Agrobacterium

Many labs were trying to figure out the details of how Agrobacterium does that, and Kosuge's group was one of them.  The goal was to "disarm" that "Ti Plasmid" so that it would no longer make the plant sick, but maintain its natural function of inserting genes. Only by understanding the detailed regions of the Ti plasmid would it be possible to only insert desirable genes.  Other approaches were being tried in other labs.  Ultimately, a tamed version of Nature's genetic engineer became the most desirable way to put new traits into a plant.   The researchers in Kosuge's lab were all just making small contributions to that ultimate development.  Many labs around the world were working on the same thing. 

The atmosphere in both of these labs was one of excitement about a distant goal of making a positive contribution to the future food supply, but it was also a group of people excited about being on the cutting edge of a field of science.  Commercial applications were a distant concept at that point.  As with those at Stanford, these researchers were concerned about making sure their work was safe.  Dr. Kosuge was instrumental in convening a major conference of "Risk Assessment in Biotechnology" that was held in Davis in 1988 and which I'll describe later.  Most of the people coming out of these labs went on to the sort of academic jobs all of us were shooting for at the time, but some moved on into the next chapter of plant biotechnology which began in the very early 1980s - the small, start-up companies.  I hope to write about that phase sometime soon.

You are welcome to comment here and/or to write me at savage.sd@gmail.com

Image of the Stanford Quad in 1978 from Wikimedia Commons
Asilomar State Beach image from Wikipedia
UC Davis water tower image from the UC Davis website
Agrobacterium graphic from Nature
Grape crown gall image from Bill Moller of UC Davis (he was one of my advisors there)