Chapter 14 Thirteen Through a Narrow Window

The biologist George Walter once compared his highly specialized research topic, "the eye-catching visual pigment," to "a small window from which a person is far away, and he He could only see a little light from the window. But as he got closer to the window, he saw more and more; until finally, as he got closer to the window, he could see the whole universe." That is to say, we should focus our research efforts first on the individual cells of the body, then on the finer structures within cells, and finally on the fundamental reactions within these institutions—only if we do so. Only then do we appreciate the serious long-term effects of accidentally introducing external chemicals into our internal environment.

Medical research has only recently given attention to the study of the function of individual cells in the production of the energy that is essential to the existence of life.The extraordinary mechanism of energy production in the human body is a fundamental issue not only for health, but for life as a whole.It is even more important than the most vital organs, because without the normal and efficient function of energy-producing oxidation, no function in the body can function.Yet many of the chemicals used to eliminate insects, rodents and weeds have the property that they hit oxidation directly and disrupt the wonderful function of this system.

The research work that brought us to our present understanding of cellular oxidation is one of the most impressive achievements in all of biology and biochemistry.The roster of people who have accomplished this work includes many Nobel laureates.For a quarter of a century it has been advancing step by step, relying on earlier work that became its cornerstone.Now, almost all the details are still to be delved into.It is only in the last decade that the whole research effort has been consolidated so that biological oxidation has become part of the common knowledge of biologists.However, a more important fact is that before 1950, medical personnel with basic training did not even have the opportunity to actually appreciate the profound importance of the changes and hazards caused by the destruction of biological oxidation.

Energy production is not done by any specialized organ, but by all the cells of the body.A living cell is like a flame, burning fuel to produce the energy necessary for life.Although the metaphor is poetic, it is not precise enough, because the cell only completes its "burning" under the condition of generating the appropriate heat required by the human body to maintain normal body temperature.Thus, thousands upon thousands of such mildly burning little flames produce the energy needed for life.If these little flames ceased to burn, says chemist Eugene Rabinovich, "hearts can no longer beat, plants can no longer grow against gravity, amoebas can no longer swim, no sense can run through nerves, No more thoughts can flash in the human brain." In cells, the transformation of matter into energy is a continuous process, one of the renewal cycles in nature, really like a wheel that keeps turning.Sugar fuel, in the form of glucose, fills the wheel particle by particle, molecule by molecule, and as it circulates, the fuel molecules undergo breakdown and a series of subtle chemical changes.These changes are carried out step by step in a very regular way, and each link is dominated and controlled by an enzyme with a specialized function. This enzyme only does one thing and does not care about anything else.In the middle of each stage, energy is produced and waste products (carbon dioxide and water) are discharged, and the changed fuel molecules are transported to the next stage.When this spinning wheel has made one full turn, the fuel molecule is exhausted and enters a new state where it is ready to combine with a new incoming molecule and start the cycle all over again.

This process is one of the miracles of the living world.In this process, the cell performs production activities like a chemical factory.It's a miracle that all the working parts are so tiny, the cells themselves are almost so tiny that they can only be seen with the help of a microscope.What's more, much of the oxidation process takes place in a tiny space, in tiny particles called mitochondria inside cells.Although such mitochondria have been known for 60 years, they have been ignored in the past as components of cells with unknown and probably insignificant roles.It was only in the 1950s that their study became an exciting and fruitful field of science; they suddenly began to attract enormous attention, with 1,000 papers appearing in a five-year period on this subject alone article.

Human beings have revealed the mystery of mitochondria, and once again demonstrated their outstanding creativity and tenacious perseverance.Just imagine such an extremely small particle, even through a microscope with a magnification of 300 times, it is difficult to see; but now there is such a technology that can separate the above-mentioned particle from other components and take it out separately , and the analysis of its components can also determine the highly complex functions of these components.It is simply unimaginable.Now, thanks to the electron microscope and the improved skills of biochemists, the work has finally been done.

Mitochondria are now known to be an extremely small enzymatic inclusion, a variable assemblage of all enzymes necessary for the oxidative cycle, precisely and orderly arranged in the mitochondrial wall and interval.Mitochondria are the "powerhouses" in which most energy-producing actions take place.After the first and first steps of oxidation are completed in the cytoplasm, fuel molecules are introduced into the mitochondria.It is here that the oxidation is accomplished; it is here that a great deal of energy is released. The endlessly turning wheel of oxidation in the mitochondria would lose all its meaning if it were not turning for this all-important purpose.The energy produced at each stage of the oxidative cycle is commonly referred to by biochemists as ATP (adenosine triphosphate), a molecule that includes three groups of phosphates. The energy-providing role of ATP is due to the ability of ATP to convert one of its phosphates into another, transferring electrons back and forth in the process and creating bond energy.Thus, in a muscle cell, when a terminal set of phosphates is delivered to the contracting muscle, the energy required for contraction is produced.So there is another cycle—a cycle within a cycle, that is, one molecule of ATP releases one group of phosphates and only keeps two groups, and becomes the diphosphate molecule ADP; but when this wheel turns further, another A phosphate group is incorporated again, and potent ATP is restored.This is just like the battery we use, ATP stands for charged battery and ADP stands for discharged battery.

ATP is the universal energy transmitter. From microorganisms to humans, ATP is found in all organisms. It provides mechanical energy for muscle cells and electrical energy for nerve cells.Sperm cells, fertilized eggs ready for a burst of activity that will develop into a frog, a bird, or a baby, hormone-producing cells, etc., all powered by ATP of. A small part of the energy of ATP is used inside the mitochondria, and most of the energy is immediately released into the cell to provide energy for various other activities of the cell.In some cells, the location of the mitochondria favors their function because they are positioned so that energy is delivered precisely where it is needed.In muscle cells, they cluster in groups around contractile muscle fibers; in nerve cells, they are found adjacent to other cells to provide energy for the transmission of excitatory impulses; in sperm cells, they are concentrated in propelling the tail and head where the parts are connected.

The process of charging an ATP-ADP battery is the coupling process in oxidation: in this battery, ADP and free phosphate groups are combined to form ATP. This tight combination is what is called coupled phosphorylation. .If this combination becomes uncoupling, this means that there is a loss of energy available for supply. At this time, breathing is still going on, but no energy is produced, and the cell becomes an idle motor, generating heat without functioning. .Then the muscles cannot contract; the impulse cannot run along the nerve channels;The consequences of uncoupling can be a real disaster for all organisms from embryos to humans, and sometimes it can lead to the death of tissues, or even whole organisms.

How does decoupling occur?Radioactivity is a coupling destroyer.Some believe that the death of cells exposed to radiation is due to the disruption of coupling.Unfortunately, a large number of chemicals also have this ability to block energy-generating oxidation, and pesticides and herbicides are typical examples of this class of chemicals.As far as we know, phenol has a strong effect on metabolism, and the rise in body temperature it causes is potentially fatal; this is caused by the result of an uncoupling action - "idle motor".Dinitrophenol and pentachlorophenol are examples of this class of chemicals that are widely used as herbicides.Another disruptor of coupling among herbicides is 2·4-D.Among chlorinated hydrocarbons, DDT is a proven coupling breaker, and further research may reveal additional breakers in this class of substances.

But uncoupling isn't the only thing that extinguishes the little flames of the millions of cells in the body.We already know that each step of oxidation is directed and facilitated by a specific enzyme.When any of these enzymes—even a single one—is destroyed or weakened, the oxidative cycle in the cell comes to a halt.No matter which enzyme is affected, the consequences are the same.The oxidation process in circulation is just like a rotating wheel. If we insert an iron rod between the spokes of this wheel, no matter which two spokes we insert, the result will be the same.For the same reason, if we destroy an enzyme that is active at any point in this cycle, the oxidation will cease.Then no more energy is produced, and the end result is very similar to uncoupling. Many of the chemicals commonly used as insecticides are this iron rod that breaks the oxidation wheel. DDT, methoxychlor, malathion, phenothiazines, and various dinitro compounds are among those insecticides which interfere with one or more enzymes involved in the oxidation cycle and are being used in large quantities. .They thus emerge as a potential effect.They are able to block the entire process of energy production and deprive cells of available oxygen.This hazard has a large number of disastrous consequences, only a small number of which can be mentioned here. Simply by systematically inhibiting the supply of oxygen, experimenters were able to turn normal cells into cancerous ones, as we will see in the next chapter.Clues to other drastic consequences of depriving cells of oxygen can be seen in animal experiments on developing embryos.By lack of oxygen, the regular processes of tissue growth and organ development are disrupted; deformities and other abnormalities ensue.If a human embryo is deprived of oxygen, it can develop birth defects. There are some indications that an increase in such disasters is now being noticed, although no one expects to discover the full causes.In one of the more ominous omens of the period, the Office of Census launched a national survey of birth anomalies in 1961, accompanied by a note that the statistic provided the facts necessary to shed light on congenital anomalies range of occurrence and the environment in which they arise.Some of the research in this area undoubtedly involves measuring the effects of radiation, although it should not be overlooked that many chemicals can have the same effects as radiation.Some of the defects and deformities that the Census Office grimly anticipates will appear in the children of the future will almost certainly be caused by chemicals that seep into our external and internal worlds. It is likely that some of the symptoms of reproductive decline are also associated with disturbances in biological oxidation and with depletion of the all-important ATP stores.Even before fertilization, the egg needs to be heavily supplied with ATP to be ready for that huge effort and huge energy expenditure that must be expended once the sperm enters the egg and fertilization occurs.A sperm cell's ability to reach and enter an egg depends on its own supply of ATP, which is produced in mitochondria concentrated in the neck of the sperm.Once the fertilization process is complete and the division of the cells begins, the energy supplied in the form of ATP will largely determine whether the development of the embryo can continue to completion.Embryologists have studied fertilized eggs of frogs and sea urchins, some of their most readily available materials, and found that if the ATP content is reduced below a certain limit, these eggs stop dividing and die soon. Not unconnected from the embryology laboratory to the apple trees on which the robin's nest holds all its blue-green eggs, but the eggs lie there cold and flickering with life After a few days it is now off.Also at the top of a tall Florida pine, where a great mass of twigs and sticks was neatly arranged, held in this nest three large white eggs, also cold and lifeless.Why don't the robins and eagles hatch eggs?Were the eggs, like those of the laboratory frogs, simply aborted due to the lack of a common energy transmitter, the ATP molecule? Is the reason for the lack of ATP due to the following reasons?The amount of pesticide already stored in the parent birds and in those eggs is enough to stop the little wheels of oxidation on which energy depends. Instead of guessing whether pesticides have accumulated in bird eggs, it is clearly easier to examine these eggs than to look at mammalian egg cells, whether the eggs are obtained under laboratory conditions or in the wild, as long as When these pesticides were detected in bird eggs, DDT and other hydrocarbons were found to accumulate in large quantities and in high concentrations.Pheasant eggs tested in California contained 349 parts per million of DDT.In Michigan, eggs taken from the fallopian tubes of robins that died of DDT poisoning contained DDT concentrations in excess of 200 parts per million.DDT can also be found in eggs left unattended in nests as old robins die from poisoning.Chickens poisoned with aldrin used on a neighboring farm also passed these chemicals on to their eggs. Experiments on hens fed DDT produced eggs containing as much as 65 parts per million. DDT. When we know that DDT and other (perhaps all) chlorinated hydrocarbons can interrupt the cycle of energy production by inactivating a specific enzyme or by disrupting the coupling of energy production, it is difficult to imagine that any containing How can a large number of poisonous bird eggs complete the complex process of its development: the infinite number of divisions of cells, the careful construction of tissues and organs, the synthesis of the most critical substances to finally form a living life.All of this requires a lot of energy—that is, the mitochondrial sacs that generate ATP from the ongoing metabolic cycle. There is no reason to assume that these catastrophic events are limited to birds. ATP is a universal transmitter of energy, and the metabolic cycle that produces ATP has the same effect whether it is in birds or in bacteria, whether it is in humans or mice. .So the fact that pesticides accumulate in the embryonic cells of any organism would be just as detrimental to us, which means comparable effects on humans. These chemicals get into the tissues that give rise to the embryonic cells, which means they also get into the embryonic cells themselves.Among pheasants, rats, and guinea pigs under controlled conditions, among robins in areas sprayed for elm disease, and in western forests active in western forests sprayed for elm bud worm Accumulations of the pesticide have been found in deer and in the reproductive organs of various birds and mammals.In a robin, the testes contain more DDT than in any other part of the body; pheasants also accumulate large amounts of DDT in their testes, exceeding 1500 parts per million. In experimental mammals, atrophy of the testes was observed, possibly as one of the consequences of this accumulation of DDT in the reproductive organs.The mice most exposed to methoxychlor had unusually small testicles.When a young rooster was fed DDT, its testicles were only 18 percent of their normal size, and their testosterone-dependent combs and wattles were only a third of their normal size. Sperm themselves are also significantly affected by the lack of ATP.Experiments have shown that the motility of male sperm is reduced by ingestion of dinitrophenol, because it disrupts the energy coupling mechanism and inevitably leads to a reduction in energy supply.Other chemicals that have been studied have also been found to have the same effect.Indications of these possible effects on humans can be seen in ancient medical reports, or in the decline of sperm production, or in agricultural aviation sprayers spraying DDT. For human beings as a whole, the wealth that is infinitely more precious than individual lives is our innate genetic material, which is our link between the past and the future.Through a long evolutionary period, our genes not only made us what we are, but also hold the future in their tiny form.However, at present, the harm caused by human factors has become a threat of our time, "this is the last and greatest danger to human civilization". Once again chemical drugs and radiation show their strict but unavoidable similarities. A radiation attack exposes a living cell to various types of damage. Its ability to divide normally may be disrupted, its chromosome structure may be altered, or genes carrying genetic material may undergo sudden changes known as "mutations." Mutations will allow cells to develop new traits in their offspring.If the cells are extremely sensitive, the cells may be killed instantly; otherwise, the cells eventually become malignant over the course of many years. The harmful consequences of these radioactive effects have been reproduced in experimental studies with a number of so-called radioactive or radioactive chemicals.Many chemicals used as pesticides, herbicides or insecticides fall into this category and have the ability to damage chromosomes, interfere with normal cell division, or cause cells to mutate.These damages to the genetic material can cause disease in the individual organisms exposed to the pesticide and can also affect future generations through its effects. Only a few decades ago no one knew these effects of radioactivity, nor the effects of these chemicals; in those days atoms had not yet been isolated, and chemicals which could mimic the bred in test tubes at home.In 1927, however, Dr. H. J. Muller, a professor of zoology at the University of Texas, discovered that exposing an organism to X-rays caused it to mutate in subsequent generations.With this discovery by Muller, a new field of scientific and medical knowledge was opened.Müller was later awarded the Nobel Prize in Medicine for his achievements.Later, the world quickly dealt with that gray fallout that caused controversy, and in this world, even if you weren't a scientist, you now knew about the potential dangers of radioactivity. Although little attention was paid to it, there was a subsequent discovery in the early 1940s.At the University of Edinburgh, Carrute Oberch and William Robertson, in their research on mustard gas, found that the chemical caused permanent metamorphosis of chromosomes that was indistinguishable from that caused by radiation.In experiments with fruit flies (an organism that Müller had also used in his early studies of the effects of X-rays), mustard gas also caused mutations in these flies.Thus, the first chemical mutagen was discovered. There is now a long list of the same mutagenic chemicals as mustard gas, which are known to alter the genetic material of animals and plants.To understand why chemicals can alter genetic processes, we must first understand the underlying evolution of life when it is in the living cell stage.If the body is to grow, if the source of life is to be passed on from generation to generation, the cells that make up the tissues and organs in the body must have the ability to proliferate continuously.This role is accomplished by means of cell mitosis or nuclear differentiation.In a cell about to divide, important changes occur first in the nucleus and eventually spread throughout the cell.Inside the nucleus, chromosomes magically move and divide in order to arrange themselves in the old pattern that can pass on the determinant of heredity -- the gene -- to daughter cells.In this way, each new cell will contain a complete set of chromosomes in which all the genetic information is coded.By means of this method, the integrity of the biological species is preserved; by means of this method, dragons beget dragons, phoenixes beget phoenixes, and sons of mice can make holes. A special type of cell division occurs during the formation of embryonic cells.Because the number of chromosomes is a constant for a certain type of organism, the egg and sperm that combine to form a new individual can only enter the new combination with half the number of chromosomes.This process is accomplished with great precision by means of changes in the behavior of chromosomes that occur during the division process that produces new cells.At this time, the chromosome itself does not split, but a chromosome separated from each pair of chromosomes enters each daughter cell intact. The key to the development of an entire life is revealed in a single cell.The process of cell division is the same for all life on earth; neither man nor amoeba, nor giant metasequoia nor tiny yeast cell, without this cell division, can no longer exists.Thus, anything that interferes with cell mitosis is a serious threat to the organism's prosperity and its progeny. "Some major features of cellular organization, such as dimensional divisions, have existed for half a billion years, perhaps closer to a billion," said George Gaylord Simonson and his colleagues Peter Tandre, Tiffany In their extensive book titled "In this sense, the living world, though certainly fragile and complex, has been incredibly durable in time - even more so than mountains Persistence. This permanence depends entirely on the almost unbelievable precision with which genetic information is reproduced from generation to generation." But never in all these millions of years has this "incredible precision" been under such immediate and massive threat as it was in the middle of the twentieth century from man-made radioactivity, man-made and human-dispersed chemicals blow.Mr McWarren Burnett, a distinguished Australian physician and Nobel laureate, considered the above to be "one of the most significant medical features of our time, the As a by-product of the production of chemical drugs never experienced, the whole barrier which protects the internal organs of the body from the altering elements has been more and more frequently breached." The study of human chromosomes is still in its early stages, so it has only recently become possible to study the effects of environmental factors on chromosomes.It was not until 1956, thanks to new techniques, that it became possible to determine precisely the number of chromosomes in human cells - 46 - and to observe them in such detail that the presence or absence of whole chromosomes or parts of them was checked out.The whole concept of genetic hazards caused by certain factors in the environment is relatively new and is rarely understood except by geneticists, whose opinions are rarely taken up.The hazards of radioactivity in all its forms are now convincingly well understood—although sometimes denied on some unexpected occasions.Dr. Muller often laments that "not only so many policy makers in government departments, but so many medical professionals reject the principles of genetics".The fact that chemicals can act in the same way as radioactivity is now little known to the general public, and likewise not understood by most medical and scientific practitioners.For this reason, the effects of commonly used chemicals (more precisely, chemicals in the laboratory) have not yet been evaluated, but it is extremely important to evaluate these effects. Mr MacWarren is not alone in assessing this potential danger.An eminent British authority, Dr. Peter Alexander, has said: "Chemicals that have a similar effect to radioactivity can represent a greater danger than radioactivity." Vision warns that various chemicals (including those typified by pesticides) "can increase the frequency of mutations as much as they are caused by radiation... In modern times when people are exposed to unusual chemicals, our genes Suffering from such mutagen has reached a level that we know almost nothing about." The general neglect of the problem of chemical mutagen may be due to the fact that chemical mutagen was originally discovered only as a matter of academic interest.Nitrogen mustard was never sprayed from the air over entire populations; its use was in the hands of experimental biologists or physiologists, who used it for cancer treatment. (Examples of patients with chromosomal disruption treated in this way have recently been reported.) But pesticides and herbicides are already in close contact with large numbers of people. With a little attention to the problem, a certain amount of specialized data can be collected on pesticides showing that they impair vital cellular processes in a variety of ways—from microscopic chromosomal damage to genetic mutations; lead to the consequences of the final catastrophe. Generations of mosquitoes exposed to DDT have transformed into a strange creature known as a hermaphrodite -- which is half male and half female. Chromosomes of plants treated with various phenols were severely damaged, genes were changed, a large number of mutations and "irreversible genetic changes" occurred.Mutations also occurred in fruit flies, the classic material for genetic experiments, when exposed to phenol; these flies developed mutations so dangerously that they were exposed to a common herbicide or urethane , to the point of death.Urethane belongs to the class of chemicals known as carbamates from which a growing number of pesticides and other agricultural chemicals are emerging.Two carbamates have actually been used to prevent sprouting of potatoes in storage—precisely because they have been shown to interrupt cell division.One of these, maleic hydrazide, is estimated to be a powerful mutagen. Plants treated with hexachlorobiphenyl (BHC) or BHC become oddly shaped, with lumpy, tumor-like protrusions on their roots.Their cells have grown in size, enlarged due to the doubling of the number of chromosomes.This chromosome doubling phenomenon will continue in future cell divisions until the cell division has to be stopped due to its size. The herbicide 2·4-D also produced lumps in treated plants, causing chromosomes to shorten, thicken, and clump together.Cell division is severely retarded.The total effect is considered to be very similar to that produced by X-rays. This is only a small illustration, and more cases can be cited.Extensive studies aimed at examining this mutagenic effect of pesticides have not been performed to date.The facts cited above are all by-products of research in cell physiology or genetics, and research directly addressing this issue is imminent. Some scientists who are willing to acknowledge the potential effects of environmental radiation on the human body are skeptical that mutagenic chemicals can do the same.They cite plenty of facts about the ability of radiation to penetrate the body, yet doubt whether the chemicals can reach embryonic cells.Once again we are hampered by the fact that we have very little direct evidence for this problem in humans.However, the discovery of a large amount of DDT accumulation in the reproductive organs and embryonic cells of birds and mammals is a strong evidence that at least chlorinated hydrocarbons are not only widely distributed in organisms, but also have come into contact with genetic material.Professor D. E. Davis of Penn State University has recently discovered that potent chemicals that prevent cell division and are used to a limited extent in cancer treatment can also cause infertility in birds.The chemical stops cell division in the reproductive organs, if not at lethal levels.Professor David has successfully carried out field experiments.It is evident, however, that there is little reason to hope and believe that the reproductive organs of all living things are immune to the various chemicals in the environment. Recent medical discoveries in the field of chromosomal abnormalities are very interesting and far-reaching.In 1959, several British and French research groups found that their independent studies had reached the common conclusion that some human diseases occurred due to the destruction of normal chromosome number.In some of the diseases and abnormalities studied by these men, the number of chromosomes did not correspond to the normal value.This fact explains why it is now known that all patients with typical Mungi-type deformities have an extra chromosome.Sometimes this extra chromosome is attached to another chromosome so that the normal number of 46 chromosomes remains.The general rule, however, is that this one extra chromosome exists independently, bringing the number of chromosomes to 47.The original cause of these patient defects must have come from the previous generation. It appears that for some patients (both American and British) with chronic leukocytosis, another mechanism is at work.The same chromosomal abnormality has been found in some blood cells.This metamorphosis involves partial deletion of chromosomes.In the skin cells of these patients, the number of chromosomes was normal.This result shows that the chromosomal defects do not occur in the embryonic cells that form these organisms, but only in certain cells, (in this case, the first victims are blood cells). Occurs during the life of the organism itself.Defects in one chromosome can render them incapable of the "instructions" that direct normal behavior. Since the opening of this new field, the variety and number of bodily defects associated with chromosomal disruption has grown at an astonishing rate, and is now beyond the scope of medical research.Only one complication known as Kranvert disease is associated with a duplication of one sex chromosome.The organism that caused the disease was male, but because it had two X chromosomes (the chromosomes became XXY instead of the normal XY male chromosomes), it became somewhat abnormal.Very high stature and mental deficiencies often accompany the infertility that occurs in this case.Conversely, organisms that get only one sex chromosome (that is, type XO, rather than XX or XY) are actually female, but lack many secondary sexual characteristics.This condition is often accompanied by various physical (and sometimes mental) defects, and the reason is of course that the X chromosome carries genes for various characteristics.This is the so-called inversion complication.These conditions were described in the medical literature long before the diseases were revealed. On the subject of chromosomal abnormalities, a large amount of research work has been done by workers from many countries.A University of Wisconsin research group led by Dr. Grouse Berto has been studying various congenital abnormalities, often including mental retardation, which appear to be caused by a partial doubling of a chromosome引起的，仿佛是在一个胚胎细胞形成的时候，一个染色体被打碎了，而其碎片未能适当地重新分配。赵种不幸可能会干扰胎儿的正常发育。 根据现有知识，一个完全多余的人体染色体的出现通常是致命的，它能阻止胎儿的生存。在这种情况下已知只有三种方式可以使胎儿继续生存，蒙古型畸形病当然是其中之一；另外，一个多余的附加染色体碎片的存在虽然会造成严重伤害，但不一定是致命的，根据威斯康星州研究者们的看法，这种情况可以很好地解释至今尚未被查清的一些病例的本质原因，在这些病例中，一个儿童带着复合的缺陷出生，这些缺陷通常包括着智力发育迟缓。 到目前为止，科学家一直都是在关心与疾病和缺陷发育有关的染色体变态的鉴定工作，而不怎么深究其原因，这是研究工作的一个新课题。假定认为在细胞分裂过程中引起染色体古怪行为的染色体损伤应该由某个单独的因素来负责，这种想法是不妥的。然而，我们难道能够无视这样一个现实吗？——我们现在正使化学物质充满我们的环境，这些化学物质有能力直接打击染色体，并以精确的方式影响染色体，造成上述情况。为了得到一个不生芽的土豆或一个没有蚊子的院落，难道我们付出这样的代价不是过高了吗？ 如果我们愿意的话，我们是能够减少对我们基因天性的这种威胁的；这种基因经过了约20亿年的活原生质的进化和选择之后，方才进入我们身体，这种基因仅在目前暂时属于我们，以后我们必将把它传给后代。我们现在竟不能保护基因的完整性。虽然化学物质的制造者们根据法律要求检验了他们产品的毒性，但是，法律却没有要求他们去检验这些化学物质对基因的确切影响，所以他们实际上也没有这样去做。