Ochiai E. Chemicals for Life and Living

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22 Holistic Chemical View of the World

Well, let us take some examples and see what this implies. The issues chosen are

organic foods and GM plants/foods, and synthetic chemicals in general and their

effects on everything they interact with: human bodies, ecosystems, and environ-

ments. These deal with chemicals and at least certain aspects of the issues can be

regarded to be within the realm of chemistry. Some speciﬁc examples have been

discussed in earlier chapters.

22.1 Organic Foods

“Organic” farming and their products, “organic” foods, are in vogue now. Having

read this book, you will realize that in fact all foods based on plants and animals are

indeed made of organic compounds, irrespective of the farming or raising methods.

From the chemistry point of view alone, therefore, there is no such thing as “non-

organic” food; all foods are organic. The “organic” designation in today’s market is

a misnomer, and is based on non-use of any artiﬁcial chemicals, both inorganic and

organic in the production.

Farming earlier was done without adding many artiﬁcial substances; it was indeed

“organic” faming. Fertilizers were natural products or their derivatives, and no weed

killer was used; weeds were removed by hand. Some natural products were used for

insect repellants. It was so only because no synthetic chemicals were available.

Since the early twentieth century, synthetic fertilizers, pesticides, and so on have

become widely available and used extensively in “conventional” farming. People

have now come to a vague realization that the product made without artiﬁcial treat-

ment (i.e., “organic food”) seems to be better (in quality) than the same produced

using artiﬁcial chemicals. Indeed some research data seem to demonstrate that the

so-called “really” organically produced food, tomato and fruit in particular, do con-

tain more nutritious compounds than their conventional counterparts (Benbrook

et al., 2008; see note below). Let us look at the potential problems of the “conven-

tional” farming and its products as against organic farming in several areas.

Plants require a number of nutrients for healthy growth as discussed in the main

body of this book. However, it had been recognized since the ﬁnal days of nine-

teenth century that the major essential elements for plant growth are nitrogen, phos-

phorus, and potassium (N–P–K). This knowledge has led to the development of

artiﬁcial fertilizers that supply these essential elements. Particularly important are

nitrogen fertilizers such as ammonium sulfate and ammonium nitrate; these are syn-

thesized in modern factories and are now used far and wide in large quantities. For

example, the so-called “Green Revolution” of rice (efﬁcient production of rice)

relied heavily on synthetic nitrogen fertilizers and others. Indeed, use of cheap syn-

thetic fertilizers in general has increased the efﬁciency of grain and other production

(quantity/unit area); a success story of chemistry. However, an excess of nitrogen

fertilizer tends to encourage vegetative growth only, producing mainly carbohy-

drates and carotenes, and less of other nutrients such as ascorbic acid. One serious

drawback of ammonium sulfate (most widely used fertilizer) is to reduce the fertil-

ity of soil as discussed earlier; other problems will be discussed later. As mentioned

27322.1 Organic Foods

in Chap. 6, a number of nutrients other than N–P–K are indeed required for healthy

growth, and these micronutrients are not taken account of when applying synthetic

fertilizers.

Plant growth will usually be hampered by a number of factors other than short-

age of nutrients (fertilizer); among them are insects, disease-causing microorgan-

isms, and weeds. The chemical industry has developed chemicals to reduce the

effects of such factors: pesticides, fungicides, and weed killers (herbicides), etc.

These are widely used in today’s farming, again to increase yield. Seeds and fruits

are often eaten by animals and birds as well. Chemicals are often sprayed to deter

such eating . The adverse effects of some of these chemicals (to the environment

and human health) are discussed in Chap. 16.

Interestingly, nature herself, i.e., plants themselves, often produce some chemicals

to deter insects, birds, and animals. Use of artiﬁcial chemicals often could discourage

plants to produce their own defense chemicals, as the artiﬁcial products applied may

provide such a defense. This is a virtually general reaction of living systems; i.e., they

try to economize their own production of chemicals as much as possible, if feasible.

For example, a substitute chemical such as an artiﬁcial hormone ingested would tend

to suppress the indigenous production of the hormone as discussed earlier in the

human body (Chap. 17). Likewise, insect repellants applied to a plant may reduce the

indigenous production of repellant such as polyphenolic substances, which, if

ingested by humans, can function as an antioxidant, a useful nutrient.

A chemical kills an insect attacking a plant; it is made for that purpose. The

chemical can, however, interact not only with the target insect, but also some other

insects or chemical substances that it gets in contact with. Such interactions may be

innocuous, or the chemical sprayed on may be easily washed away or may not be.

Here lies the basic problem; the whole picture of even a single chemical’s interac-

tions with all the components of the system (in this case, insect(s) and plant, plus

soil, the other surrounding plants and humans eventually eating it) may not be

sought or even be considered often in the process of developing such a chemical.

Use of a chemical is directed at a speciﬁc problem: supply of a nutrient, killing

bugs, or killing weeds. This is a typical chemical approach; ﬁnding out the cause of

a problem and then correcting that problem with a speciﬁc chemical agent. To obtain

an overall good result may require a number of chemicals targeted at different prob-

lems. The purpose pursued here in this efﬁciency-conscious society is often the

overall yield of product; i.e., increased quantity. The overall better yield of a plant

can often be measured as an increase in the bulk components (such as starch or cel-

lulose), which in turn dilute relatively minor components. Some of these minor

components may be involved in enhancing the nutritional value and the taste for

human consumption; examples are the content of vitamins, particularly vitamin C

or sugar component. This is particularly true in seed bodies, i.e., fruits and vegeta-

bles such as cucumber. Because such an individual body starts with a ﬁxed number

of cells, a larger fruit body contains on average larger cells and/or larger air space

between cells. And such intercellular spaces would contain few nutrients. This

means that the larger fruit (higher quantity in general) tends to contain less density

of nutrients.

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22 Holistic Chemical View of the World

Now let us get back to the so-called organic farming/food. The rationales for

such farming are not well spelled out; it is based on the vague notion that “natural”

is better than “artiﬁcial” in any way. The farming practices must have been devel-

oped naturally to the best degree attainable before the introduction of artiﬁcial

chemicals: fertilizers, insecticides, etc. Synthetic chemicals developed as above

should have exhibited their speciﬁc effects and most of them did so, but many of

them have turned out to cause a number of undesirable consequences. Hence it

might be wise to return to the practice without artiﬁcial chemicals.

Well, does this notion make sense? Does the so-called organic farming produce

better food? First of all, the organic farming practice is based on the accumulated

knowledge and wisdom of farmers over several millennia. The particular species

and the farming practice have been selected to best suit the local condition. Fertilizers

were produced from plants’ and animals’ wastes, which might contain all the neces-

sary ingredients for healthy growth of a plant, not only the major nutrients such as

nitrogen, potassium, and phosphorus, but also some of important minor ones such

as calcium, iron, magnesium, and zinc. A chemically pure, factory-synthesized fer-

tilizer would not contain these important micronutrients. Besides, the organic por-

tion of such traditional fertilizers would enrich the soil. In other words, the traditional

fertilizers not only provide necessary nutrients for plant growth but also make the

soil more fertile for future farming. This has something to do with the interactions

of the organic substances and the structure of soil. That is, whereas a synthetic fertil-

izer each provides a speciﬁc nutrient, the traditional fertilizer provides most of the

necessary nutrients. In the philosophical term, the synthetic fertilizer represents the

analytical way of nutrient-provision, while the traditional one represents a holistic

nutrient provider. Hence the traditional fertilizer would encourage overall healthy

growth, while an individual synthetic fertilizer, e.g., ammonium sulfate, encourages

only vegetative growth.

This is the ideal of organic farming, but the reality may be much less ideal; the

traditional, natural fertilizers applied may not be sufﬁcient in both quantity and

quality. Of course, it depends on the practice of farming.

There is a lot of anecdotal evidence for the superiority of organic foods: “organi-

cally grown tomato tastes much better than those grown in the conventional man-

ner”; etc. Is there a sound scientiﬁc basis for such a comparison? It turned out that

such a comparison is not easy to conduct satisfactorily in the scientiﬁc sense. In

other words, it is rather difﬁcult to compare different farming methods because the

basic condition (other than applied material) has to be set to the same level in scien-

tiﬁc sense; soil fertility, water, sunlight, temperature, plant arrangement, etc.

A survey by Benbrook and coworkers (see note below) of the reports on

comparison of “organic foods” vs. “conventional products” carefully evaluated the

scientiﬁc validity of each one. They found 236 scientiﬁcally valid pairs with regard

to 11 nutrients (potassium, phosphorus, the total proteins, vitamins, and antioxi-

dants), among literatures published in 1980–2007. The organic foods were

nutritionally better in 61% (145 pairs) of the cases of all the matched pairs. On the

one hand, the conventionally raised food contained more nutrients than its organic

counterparts, among 87 matched pairs (37%). In three quarters of these 87 cases

27522.2 GM Plants/Foods

where the conventional ones were more nutritious, the nutrients found more in the

conventional products were potassium, phosphorus, and total protein levels. These

nutrients are usually adequately provided by other foods and are not critical. On the

other hand, the major nutrients more abundant in the majority of the organic food of

the 145 pairs were polyphenols and antioxidants including vitamin C and E. In

terms of quantity of nutrients, one quarters of the organic foods contained 31% or

more of the nutrients than the conventional counterparts, and almost one-half con-

tained 21% or more. These researchers concluded: “Yes, organic plant-based foods

are, on average, more nutritious.”

(Note: Benbrook, Charles; Zhao, Xin; Yáñez, Jaime; Davies, Neal; Andrews,

Preston, (2008), “State of Science Review: Nutritional Superiority of Organic Food,”

http://www.organic-center.org).

This study indeed indicates the general superiority of organically produced foods

in terms of important nutrients, but of course the organic foods may not necessarily

be superior in all kinds of nutrients. Besides, careful and conscientious application of

organic farming methods and material is necessary to assure a better quality of the

products, as in any case. Issues to be carefully weighed for all farming to rely on this

method (organic) include: (1) whether the method is sufﬁcient for preventing or tol-

erating attack by insects and disease-causing microorganisms, and (2) whether organic

farming alone can provide enough nutrition for all the human beings on this planet

today and in the future. The latter depends heavily not only on the technical details

but also on the social conditions including distribution methods of food and others.

22.2 GM Plants/Foods

GM stands for “Genetically Modiﬁed.” Unraveling the secret of the functions of

gene has prompted some quarters to attempt to manipulate the genes in plants (and

some animals) for our purposes. Several important factors are mentioned in the

previous section, which facilitate plants’ healthy growth; nutrients (fertilizers), and

defense chemicals (insecticide, fungicide, and herbicide, etc.). The intention of

those who would use the knowledge of genetics has been to produce plants that

would grow healthily without much added extraneous chemicals, such as fertilizers,

insecticides, and herbicides, or in a certain case would withstand a speciﬁc herbi-

cide, by manipulating the genes.

For example, clover and some bean plants produce their own nitrogen fertilizers

(ammonia, NH

). You may have seen small round things attached to the roots of

clover. These small nodules contain an enzyme called nitrogenase that converts

nitrogen (N

) in the air into ammonia. If a gene of this enzyme was incorporated into

a plant gene system and if the plant was made to produce this enzyme, then the

requirement for nitrogen fertilizer would be greatly reduced for such a plant. This is

the kind of thinking behind the efforts to create “GM” plants. This particular (gene)

modiﬁcation has not yet been successful.

Alternatively, a gene may be introduced into a useful plant so that it can tolerate

an extraneous chemical such as herbicide. Then the plant can grow in the presence

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22 Holistic Chemical View of the World

of the herbicide while other plants, e.g., weeds can be eliminated by the applied

herbicide. Of course, one may simply incorporate an insecticide-producing gene

itself into the gene system of a plant, so that the necessity of applying insecticide

may be lessened for the plant.

As in the use of chemicals in conventional farming, the problems arise from the

paucity of experimental data on the overall effects of such a gene manipulation.

More detailed studies need to be conducted before a widespread use of such a

technique, though, in reality, some GM plants are now widely planted in many

countries.

Before some examples are discussed, let us focus on the widely held conviction

or rather justiﬁcation for the use of GM technology. That is: “the gene manipulation

has been practiced in the form of cross-species-breeding and selection over the mil-

lennia, and this new technique is no different, and it only speeds up and enhances

such an effort. Besides, the biological evolution itself is such a gene manipulation

by nature.” Natural crossbreeding has its limitation because it can happen only

among similar organisms. On the contrary, GM technique can incorporate e.g., a

bacterial gene into a plant; this is not usually feasible in nature. (Though, it could

have happened in nature in the event of formation of eukaryotic organisms by sym-

biotically incorporating prokaryotes. For example, mitochondrion is believed to be

a former aerobic prokaryote incorporated in a eukaryotic cell).

Natural selection would have eliminated a crossbred species if the product

species would not ﬁt. Nature in general would have selected a best-suited species in

the niche. “Being best-suited” implies a species that would survive best under the

circumstance, and, ideally, also implies a species that would provide the best quality

for the farmer who was attempting to crossbreed. On the other hand, a species that

is obtained by artiﬁcial gene manipulation is not directly subject to the elimination

process by nature (the ecosphere), and it may eventually become dominant or extinct

if left to the natural selection pressure. This process may take decades or much

longer or even shorter. However, it is likely that artiﬁcial interventions may preclude

the action of natural selection, thus forcing the GM species to be artiﬁcially

dominated by, e.g., using the same GM seed every growing season. Meanwhile how

a GM plant affects the ecology is uncertain. The plant-growing process is difﬁcult

to be conﬁned spatially because of cross-pollination, etc, and hence the gene

artiﬁcially embedded in a GM plant may be transmitted to other plants in the

ecosphere.

Another issue is that the newly incorporated gene would not only produce a

substance that must be usually beneﬁcial to the plant growth, but that it may also

produce other substances or interfere with the production of other substances and

may not necessarily be beneﬁcial for human consumption. These need to be care-

fully investigated and evaluated before a GM plant is allowed to be widely grown.

The reality is always less than ideal; for example, the process that is supposed to

incorporate a particular gene may inadvertently introduce factors (genes and others)

other than intended. And these other factors unintentionally incorporated may be

harmful, when the product of the GM plant is consumed. This is a technical issue;

techniques are not always perfect.

27722.2 GM Plants/Foods

(Note: Another basic problem is economical; in other words, a few large

corporations seem to be intent on controlling the world agriculture through attempts

to become the sole distributors of the GM plants, i.e., seeds. However, this is not a

scientiﬁc issue).

A few examples will now be discussed. One of the most widely used GM plants

is soybean resistant to herbicide “Roundup.” Roundup is a trade name of glyphosate,

which is effective and widely applied. If a useful plant like soybean is made resis-

tant to Roundup, the herbicide can be used very easily and worrilessly to eliminate

all other plants including weed that grow in the same lot. Glyphosate (its isopro-

pylamine salt) is an inhibitor of an enzyme 5-enolpyruvylshikimate-3-phosphate

synthase, which is necessary for the formation of aromatic amino acids such as

tyrosine, tryptophan, and phenylalanine. Hence glyphosate will kill the plants that

come into contact with it. Some microorganisms including Agrobacterium CP4

have a version of the enzyme that is not inhibited by glyphosate. Hence a plant with

the gene for this particular version of the enzyme will tolerate glyphosate, whereas

others will be killed by the herbicide. So the gene of a plant has been genetically

modiﬁed to incorporate the gene of this enzyme. This is the principle. Roundup-

resistant crop has been developed for soybean, corn, sugar beet, and others.

Glyphosate is supposed to be nontoxic to mammals and humans, as the shiki-

mate pathway is not present in them. Glyphosate inhibits the binding of phosphoe-

nol pyruvate to the active site of the enzyme, and phosphoenol pyruvate is one of the

pivotal metabolites present in all organisms, plants, and animals. Hence the residual

glyphosate in the food consumed by humans has the potential to effect the meta-

bolic pathways. It has been reported that indeed some toxicities are associated

with glyphosate (see for example: http://www.percyschmeiser.com/Toxic.htm).

Glyphosate has been shown to damage some beneﬁcial microorganisms in soil, to

interfere with uptake of nutrients by plants and also affect negatively the symbiotic

nitrogen ﬁxation. These factors were not taken into account while promoting

Roundup. The commercial formula of Roundup contains chemicals other than the

main ingredient glyphosate; they are a surfactant and others. A surfactant is used to

facilitate the incorporation of glyphosate into plant cells. Many surfactants are

known to cause disruption of reproductive processes in many animals including

human beings. Indeed a substantial increase in miscarriage, infant malformation,

and others has been reported among the people in some areas in Argentina where a

huge amount of Roundup was sprayed.

Another issue is that repeated use of a same herbicide Roundup may enhance the

development of a resistance against it among some plants including the weeds that

are intended to be the target of Roundup. Indeed the so-called superweeds that are

resistant to Roundup have already developed in some areas. This will necessitate an

increased use of the herbicide and eventually may also require use of other herbi-

cides. This will negate the original intention of this GM plant.

Another popular GM plant is “Bt”-cotton and others. “Bt” stands for “Bacillus

thuringiensis,” which is known to produce several toxins to kill some insects.

A toxin is modiﬁed in its DNA sequence by introducing introns, polyA signals,

promoters, and enhancers. The modiﬁed DNA is then incorporated into the gene of

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22 Holistic Chemical View of the World

cotton (or others). The thus-modiﬁed cotton will produce the toxin that is a little

altered to make it more active and more soluble in the plant cells. The toxicities of

Bt-toxins in the natural state have been evaluated in mammals and environments,

but that of the artiﬁcially modiﬁed in the GM crops has not been tested. It has been

assumed that the toxins produced in the GM plants should be equivalent to the natu-

ral ones, because the toxin-encoding domain of the DNA is the same both in the

natural and the artiﬁcial one. Nature is capable of producing Bt-resistant strains of

insects through evolutionary processes, and indeed reports have already been pub-

lished that indicate emergence of Bt-resistant insects.

In general, GM plants may work proﬁtably for a while, but it is very likely that

Nature would eventually defeat their advantages.

22.3 Synthetic Chemicals in General

Synthetic or artiﬁcial chemicals are those that have been synthesized by human

beings. Naturally occurring compounds can also be synthesized artiﬁcially. If such

a compound is pure, it should be chemically the same as the corresponding natural

one. The basic problems with the synthetic non-natural compounds stem from the

fact that they have not been present in Nature until humankind synthesized them in

recent centuries. Nature has been dealing with all the naturally occurring chemicals,

and as a result, Nature has been able to maintain its integrity in the presence of these

compounds.

The ways Nature deals with chemicals are physical (force and heat) and/or

chemical. Particularly important is the biological processes that are chemical process

at molecular level. Chemicals interact with the biological systems and are modiﬁed

to the forms appropriate for them and, if toxic, may be rendered harmless in some

cases. The biological and ecological systems, as a whole, know how to deal with

those chemicals inherent in Nature, though individual organisms may or may not be

able to cope with them all.

In order to sustain oneself, an organism produces chemicals harmful to other

organisms that compete with it for its survival. These chemicals often kill the target

organisms; these are naturally occurring chemical weapons. A few examples are

discussed in Chap. 17. Many antibiotics used in human civilization are chemical

weapons produced by microorganisms to kill other microorganisms (Chap. 7).

The target organism may counteract such a chemical, by evolving a mechanism to

render it harmless.

Humankind, having learned how to synthesize compounds, has produced an

enormous number of non-natural chemicals in the last one-and-a-half century.

Nature, the ecological system and the organisms in it including the human body, has

had no experience to deal with them when they ﬁrst appeared on the earth. Some of

them may be harmless to most organisms and simply be tolerated by them. Others

can become harmful to some organisms beyond a certain threshold level. Yet others

can be toxic even at a low level; they cannot be rendered harmless as the organisms

do not have mechanisms to detoxify them.

27922.3 Synthetic Chemicals in General

Some of these examples have been discussed in the main body of this book, but

another important issue has not been dealt with. That is the issue of “synergy.”

When two or more compounds act simultaneously, the combined effect may be

much greater than the sum of the effects of the individual compounds. In reality, it

is quite rare that a single agent acts at a single location and at a single instant. There

are always a multitude of compounds present even in a single cell, into which two

extraneous compounds are supposed to enter. The two compounds may interact

with one another, maybe forming another compound, and each of these compounds

interact with the compounds present in the cell in a variety of ways. Or one com-

pound elicits an effect and the other compound enhances or reduces the effect. There

are a number of ways that two or more compounds exert “synergistic” effects.

Chemistry has been focused on the effect of a single compound at a single location

and at a single time (instant and scale). Multiple and simultaneous effects of several

compounds have not been well researched and understood yet because of their

complexities.

Huge numbers and quantities of artiﬁcial compounds have been created and

dispersed on this earth, and their combined effects are only now becoming manifest,

but humankind as a whole does not have a clear picture of their extents and effects.

Understanding of this whole issue requires more than chemical knowledge.

281

E. Ochiai, Chemicals for Life and Living,

The author gratefully acknowledges the permission for the use of copy-righted

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Acknowledgement