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The growing crisis of Pesticides in Agriculture

The good earth is under siege. Its crops are being attacked by increasing myriads of insects.
Fighting back is man. His weapons a bristling arsenal of more than 50,000 commercial chemicals.
How did it happen? Is there no way out of this unending struggle?


CHEMICAL warfare" is a fact of life. It is, today, man's last arsenal against crop-destroying insects.

These chemicals affect not only insects but man himself. They affect everyone — and that includes you. No matter who you are or where you live, you consume, in your food, pesticides originally meant for insects. And you carry these chemicals around in your body.

More than a billion pounds of pesticides have already accumulated in the earth's air, water, soil, living plants and animals; and the amount grows daily.

What these poisons are doing to the entire web of life — and to personal health — is only beginning to be known.

But what is already known ought to tell us that, unless we drastically change our ways, we are heading for disaster.


Life Chain Threatened

The most common of the pesticides are DDT and other chlorinated hydrocarbons.

These are especially vicious pollutants. They are very stable compounds and are not easily broken down. And because of their persistence, they cause dangerous biological concentrations in the food chain. They end up ultimately in the human body. Here is what happens:

Ocean water, for example, contains phytoplankton — the producer of over half the world's oxygen supply and the first link of the chain of life in the sea. Not only does DDT decrease oxygen-producing photosynthesis, it has a tendency to be accumulated in biological organisms and passed up the food chain — from phytoplankton to zoo-plankton, shrimp, small fish, larger fish and then fish-eating birds. By the time we get to the birds, the concentration may have accumulated an astounding 10 million times over the original amount present in the ocean water.

Likewise on land, these poisons are extremely destructive to microorganisms and other minute forms of life and life-processes in the soil. Interference with these little-understood — but vitally important — links in the ecological cycle have profound effects.

Land birds, for example, accumulate DDT by eating DDT affected earthworms, caterpillars, etc. Since man eats some animals high up on the food chain, the potential danger to man is obvious.


Chemicals of Extinction

Chemists had something great, they thought, when they introduced these highly toxic chemicals. Insects perished by the millions when DDT and related chlorinated hydrocarbons were first applied.

Chemists of course knew that the chlorinated hydrocarbons are almost insoluble in water, but highly soluble in lipids (fats or fat-like materials). Since all organisms contain lipids, the chlorinated hydrocarbons — including DDT — always move from nonbiological, inorganic substances into biological organisms where they are retained.

That is why animals in every part of the earth — including penguins in the Antarctic — have traces of DDT in their body fat.

Man is no exception. The average Briton has 5 ppm (parts per million) DDT in his fatty tissue, the average American 10-12 ppm, and the average person in India 25 ppm. Collectively, more than 20 tons of DDT is being carried around in the fatty tissues of Americans.

Research on the subtle or long-range effects of chlorinated hydrocarbons is just beginning — especially in regard to man. But what is happening to birds and animals ought to sound the alarm.

Pesticides have virtually wiped out certain bird species by upsetting an intricate hormone-enzyme relationship which causes thin-shelled eggs that crack and fall apart easily. They have caused fatal nervous breakdowns in wildlife by interrupting the nerve communication system. Recent research indicates DDT causes a marked alteration in the sexual mechanisms of rats and a proneness to cancer in animals from mice to cattle.

Dr. Charles Wurster, one of the leading authorities on chlorinated hydrocarbons, says of these chemicals: "All are nerve poisons. They cause instability or spontaneous 'firing' of nerve cells, and increased doses result in tremors or convulsions — typical symptoms of acute poisoning that can occur in organisms ranging from houseflies to man. In general, if an organism has nerves, the chlorinated hydrocarbons can kill it" (Weeds, Trees and Turf, August 1969).

Dr. Joseph J. Hickey, professor of wildlife ecology at the University of Wisconsin puts it bluntly: "DDT is a chemical of extinction."

Stanford biologist, Peter Raven, asserts: "There is rock-solid evidence on what these chemicals do to other animals. It would be a bad mistake to think that man is unique."

As the harmful effects come to light, many around the world are beginning to speak out against the use of DDT and the chlorinated hydrocarbons. But has this public outcry — and even limiting or outlawing DDT in certain states and countries — curtailed the use of pesticides as a whole?

Not at all! Man heedlessly and recklessly develops and uses new and more potent pesticides than ever before with little or no concern for the ultimate outcome.


Nerve Gases Used as Pesticide

In many areas, organic phosphors are being substituted for DDT and chlorinated hydrocarbons. These were originally developed in World War II as German nerve gases. Chemically, they are cousins to the nerve agents GD and VX involved in the current chemical and biological warfare controversy.

Some fifty million pounds of organic phosphors are being spread unchecked as pesticides on America's farms and gardens annually.

Because these pesticides break down much more quickly than chlorinated hydrocarbons, many assume they are safer. The truth is that these odorless and colorless chemicals are potentially even more dangerous.

Dr. Alice Ottoboni, California State Public Health Department toxicologist, says of organic phosphors : "As a class, they are more immediately harmful to man and animals than the persistent ones." Minute amounts can kill almost instantly either by contact or by being swallowed.

Also, a nonpersistent pesticide does not just "disappear." As it breaks down "It becomes another chemical that may be less or more toxic than its parent," warns Dr. Ottoboni. Very little is known of the environmental fate of these degraded products of pesticides, either persistent or nonpersistent.

But in spite of not knowing what the ultimate outcome will be, man blindly continues to use ever more potent chemicals in ever greater quantities.


The Vicious Cycle

Another major problem with using pesticides is that natural enemies of the pest are often killed along with the pest. Since these natural enemies were partially successful in controlling the pest population, wiping them out temporarily leaves the pest free of important natural restraints. Under these circumstances, the pest will develop a resistance through mutation and again multiply before the natural enemies can multiply to control them.

This resistance of insects to pesticides is a mounting worldwide problem. Between 1908 and 1945 only 13 species of insects had developed resistance. Now the figure stands at almost 150!

The current practice employed to control these new hardy pests is to develop a new, more potent pesticide. Instead of controlling or killing the insect pests, a vicious cycle is created — stronger insects, more toxic pesticides and an increasing threat to all life forms on this planet.


No Way Out?

Here then is our dilemma: We are told that if pesticides were completely withdrawn from use, crop and livestock production would drop from 25 to 50 percent — that commercial production of apples, peaches, cherries, grapes, cranberries, raspberries, strawberries, citrus and a host of other products would come to a halt — and that millions would have their diet drastically altered or reduced.

But if we continue to use pesticides we also are in deep trouble. Survival is at stake.

Not only will pollution reach critical proportions, but as insects develop resistance faster than new pesticides can be developed, it is just a matter of time until these insects will begin to destroy food crops wholesale. And mankind will be utterly unable to stop them.

Some look to biological control to provide an out. But so little money and effort is being spent on research in this area — and progress comes so slowly — that this appears to be a false hope. In addition, there are whole categories of pest problems with no remote prospect of biological control.

Have we then painted ourselves into a corner? Is there no way out? Is there no way that insect plagues can be stopped without using pesticides?

The surprising answer is that there IS a way out.

Let's begin to explore what the solution is by asking some very basic questions — and finding some very simple, yet profound answers.

Do insects have a purpose? What causes insects to attack plants and become "pests"? Few seem to know.


The Purpose of Insects

Insects constitute 70 to 80 percent of all animal species. They are so numerous that no one knows how many species there really are. More than 800,000 have already been classified and 10,000 more are being classified annually.

There are almost as many insects on every square mile — three billion — as there are humans on earth.

Insects multiply rapidly. A single pair of flies is potentially capable of producing 191,010,000,000,000,000,000 offspring in just four months! If they all survived, the earth would be covered to a depth of 47 feet!

This cannot happen because the laws governing nature never permit a single species, plant or animal, to dominate any environment completely. Weather factors — such as temperature and rainfall — limit the distribution of an insect species. Toads, lizards, frogs, moles, snakes, birds, bats, shrews and other creatures feed largely on insects. Some birds eat their own weight in insects every day. Predatory insects prey on other insects. Larvae of parasitic insects develop in the eggs, the young or the adults of other insects. Viruses, fungi and bacterial diseases also help control the insect population.

In fact, if the insects were not kept in check by these natural forces, it is doubtful whether any conceivable volume of chemicals could possibly keep down their populations. Yet we are seldom aware of nature's own controls.

All these natural checks do their work without threatening man. Insecticides, which contribute only a very small part of the total controlling force over harmful insects, are threatening all life. Doesn't it make sense for man to encourage the balance of nature rather than devastate nature's natural controls at every turn?

It is not generally realized that less than one percent of the insect species are considered pests to man. We can figure the crop loss due to these pests with a fair degree of accuracy (about $4 billion annually in the U.S.). But the positive benefits of insects are often overlooked because they are more difficult to estimate.

It is easy to forget that bees, wasps, flies, butterflies and other insects pollinate plants that provide us with fruits and vegetables; or that some insects are vital links in the food chains of fish, birds and land animals; or that others act as scavengers of animal and vegetable debris and others as aerators of soil; or that still others are parasites or predators of damaging insects.

Instead of studying the habits of insects and implementing natural control methods, many now simply mow them down with spray guns.

For the most part, the function of "harmful" insects is all too little understood. Now, happily, some few scientists are beginning to realize the relationship between soil fertility, crop production and pests.


Why Insect "Pests"?

In his landmark book An Agricultural Testament, the famous British agriculturist Sir Albert Howard relates how in five years' time at a research station in India he "had learnt how to grow healthy crops, practically free from disease, without the slightest help from mycologists, entomologists, bacteriologists, agricultural chemists, statisticians, clearing-houses of information, artificial manures, spraying machines, insecticides, fungicides, germicides, and all the other expensive paraphernalia of the modern Experiment Station." In other words, Sir Albert worked with the principles any small farmer could use economically.

From his experience, he observed that: "Insects and fungi are not the real cause of plant diseases but only attack unsuitable varieties or crops imperfectly grown. Their true role is that of censors for pointing out the crops that are improperly nourished and so keeping our agriculture up to the mark. In other words, the pests must be looked upon as Nature's professors of agriculture: as an integral portion of any rational system of farming.

"The policy of protecting crops from pests by means of sprays, powders, and so forth, is unscientific and unsound as, even when successful, such procedure merely preserves the unfit and obscures the real problem — how to grow healthy crops" (p. 161).

These conclusions are not dreams of a man who failed. Sir Albert was knighted for these very agricultural researches — for effectively proving the usefulness of the system.

Many who have worked with the soil have noticed the tendency of insect pests to prefer plants that are weak, sickly, unhealthy, unbalanced or just a little "under the weather."

This deficiency or imbalance may be so subtle or so slight that it cannot be measured or analyzed by present scientific methods. Because science cannot ascertain this imperfection — and, judging by the paltry amount of research being done in this area, is not interested in finding out — it usually pretends that no imperfection exists. But it does exist. And the bugs know it!

Now take the cause-effect relationship a step further. What is it that causes plants to be weak and inferior — prone to insect attack?