most of us this is of less importance than the innumerable small-scale exposures to which we
are subjected day by day, year after year. Like the constant dripping of water that in turn wears
away the hardest stone, this birth-to-death contact with dangerous chemicals may in the end
prove disastrous. Each of these recurrent exposures, no matter how slight, contributes to the
progressive buildup of chemicals in our bodies and so to cumulative poisoning. Probably no
person is immune to contact with this spreading contamination unless he lives in the most
isolated situation imaginable. Lulled by the soft sell and the hidden persuader, the average
citizen is seldom aware of the deadly materials with which he is surrounding himself: indeed, he
may not realize he is using them at all. So thoroughly has the age of poisons become
established that anyone may walk into a store and, without questions being asked, buy
substances of far greater death-dealing power than the medicinal drug for which he may be
required to sign a ‘poison book’ in the pharmacy next door. A few minutes’ research in any
supermarket is enough to alarm the most stouthearted customer—provided, that is, he has
even a rudimentary knowledge of the chemicals presented for his choice.
If a huge skull and crossbones were suspended above the insecticide department the customer
might at least enter it with the respect normally accorded death-dealing materials. But instead
the display is homey and cheerful, and, with the pickles and olives across the aisle and the bath
and laundry soaps adjoining, the rows upon rows of insecticides are displayed. Within easy
reach of a child’s exploring hand are chemicals in glass containers. If dropped to the floor by a
child or careless adult everyone nearby could be splashed with the same chemical that has sent
spraymen using it into convulsions. These hazards of course follow the purchaser right into his
home. A can of a mothproofing material containing , for example, carries in very fine print the
warning that its contents are under pressure and that it may burst if exposed to heat or open
flame. A common insecticide for household use, including assorted uses in the kitchen, is
chlordane. Yet the Food and Drug Administration’s chief pharmacologist has declared the
hazard of living in a house sprayed with chlordane to be ‘very great’. Other household
preparations contain the even more toxic dieldrin.
Use of poisons in the kitchen is made both attractive and easy. Kitchen shelf paper, white or
tinted to match one’s color scheme, may be impregnated with insecticide, not merely on one
but on both sides. Manufacturers offer us do-it-yourself booklets on how to kill bugs. With
push-button ease, one may send a fog of dieldrin into the most inaccessible nooks and crannies
of cabinets, corners, and baseboards. If we are troubled by mosquitoes, chiggers, or other
insect pests on our persons we have a choice of innumerable lotions, creams, and sprays for
application to clothing or skin. Although we are warned that some of these will dissolve varnish,
paint, and synthetic fabrics, we are presumably to infer that the human skin is impervious to
chemicals. To make certain that we shall at all times be prepared to repel insects, an exclusive
New York store advertises a pocket-sized insecticide dispenser, suitable for the purse or for
beach, golf, or fishing gear.
We can polish our floors with a wax guaranteed to kill any insect that walks over it. We can
hang strips impregnated with the chemical lindane in our closets and garment bags or place
them in our bureau drawers for a half year’s freedom from worry over moth damage. The
advertisements contain no suggestion that lindane is dangerous. Neither do the ads for an
electronic device that dispenses lindane fumes—we are told that it is safe and odorless. Yet the
truth of the matter is that the American Medical Association considers lindane vaporizers so
dangerous that it conducted an extended campaign against them in its Journal.
The Department of Agriculture, in a Home and Garden Bulletin, advises us to spray our clothing
with oil solutions of DDT, dieldrin, chlordane, or any of several other moth killers. If excessive
spraying results in a white deposit of insecticide on the fabric, this may be removed by
brushing, the Department says, omitting to caution us to be careful where and how the
brushing is done. All these matters attended to, we may round out our day with insecticides by
going to sleep under a mothproof blanket impregnated with dieldrin. Gardening is now firmly
linked with the super poisons. Every hardware store, garden-supply shop, and supermarket has
rows of insecticides for every conceivable horticultural situation. Those who fail to make wide
use of this array of lethal sprays and dusts are by implication remiss, for almost every
newspaper’s garden page and the majority of the gardening magazines take their use for
granted. So extensively are even the rapidly lethal organic phosphorus insecticides applied to
lawns and ornamental plants that in 1960 the Florida State Board of Health found it necessary
to forbid the commercial use of pesticides in residential areas by anyone who had not first
obtained a permit and met certain requirements. A number of deaths from parathion had
occurred in Florida before this regulation was adopted.
Little is done, however, to warn the gardener or homeowner that he is handling extremely
dangerous materials. On the contrary, a constant stream of new gadgets make it easier to use
poisons on lawn and garden—and increase the gardener’s contact with them. One may get a
jar-type attachment for the garden hose, for example, by which such extremely dangerous
chemicals as chlordane or dieldrin are applied as one waters the lawn. Such a device is not only
a hazard to the person using the hose, it is also a public menace. The New York Times found it
necessary to issue a warning on its garden page to the effect that unless special protective
devices were installed poisons might get to the water supply by back siphonage. Considering
the number of such devices that are in use, and the scarcity of warnings such as this, do we
need to wonder why our public waters are contaminated?
As an example of what may happen to the gardener himself, we might look at the case of a
physician—an enthusiastic sparetime gardener—who began using DDT and then malathion on
his shrubs and lawn, making regular weekly applications. Sometimes he applied the chemicals
with a hand spray, sometimes with an attachment to his hose. In doing so, his skin and clothing
were often soaked with spray. After about a year of this sort of thing, he suddenly collapsed
and was hospitalized. Examination of a biopsy specimen of fat showed an accumulation of 23
parts per million of DDT. There was extensive nerve damage, which his physicians regarded as
permanent. As time went on he lost weight, suffered extreme fatigue, and experienced a
peculiar muscular weakness, a characteristic effect of malathion. All of these persisting effects
were severe enough to make it difficult for the physician to carry on his practice. Besides the
once innocuous garden hose, power mowers also have been fitted with devices for the
dissemination of pesticides, attachments that will dispense a cloud of vapor as the homeowner
goes about the task of mowing his lawn. So to the potentially dangerous fumes from gasoline
are added the finely divided particles of whatever insecticide the probably unsuspecting
suburbanite has chosen to distribute, raising the level of air pollution above his own grounds to
something few cities could equal. Yet little is said about the hazards of the fad of gardening by
poisons, or of insecticides used in the home; warnings on labels are printed so inconspicuously
in small type that few take the trouble to read or follow them. An industrial firm recently
undertook to find out just how few. Its survey indicated that fewer than fifteen people out of a
hundred of those using insecticide aerosols and sprays are even aware of the warnings on the
containers.
The mores of suburbia now dictate that crabgrass must go at whatever cost. Sacks containing
chemicals designed to rid the lawn of such despised vegetation have become almost a status
symbol. These weed-killing chemicals are sold under brand names that never suggest their
identity or nature. To learn that they contain chlordane or dieldrin one must read exceedingly
fine print placed on the least conspicuous part of the sack. The descriptive literature that may
be picked up in any hardware or garden-supply store seldom if ever reveals the true hazard
involved in handling or applying the material. Instead, the typical illustration portrays a happy
family scene, father and son smilingly preparing to apply the chemical to the lawn, small
children tumbling over the grass with a dog. . . .
The question of chemical residues on the food we eat is a hotly debated issue. The existence of
such residues is either played down by the industry as unimportant or is flatly denied.
Simultaneously, there is a strong tendency to brand as fanatics or cultists all who are so
perverse as to demand that their food be free of insect poisons. In all this cloud of controversy,
what are the actual facts? It has been medically established that, as common sense would tell
us, persons who lived and died before the dawn of the DDT era (about 1942) contained no trace
of DDT or any similar material in their tissues. As mentioned in Chapter 3, samples of body fat
collected from the general population between 1954 and 1956 averaged from 5.3 to 7.4 parts
per million of DDT. There is some evidence that the average level has risen since then to a
consistently higher figure, and individuals with occupational or other special exposures to
insecticides of course store even more. Among the general population with no known gross
exposures to insecticides it may be assumed that much of the DDT stored in fat deposits has
entered the body in food. To test this assumption, a scientific team from the United States
Public Health Service sampled restaurant and institutional meals. Every meal sampled
contained DDT. From this the investigators concluded reasonably enough, that ‘few if any foods
can be relied upon to be entirely free of DDT.’ The quantities in such meals may be enormous.
In a separate Public Health Service study, analysis of prison meals disclosed such items as
stewed dried fruit containing 69.6 parts per million and bread containing 100.9 parts per million
of DDT! In the diet of the average home, meats and any products derived from animal fats
contain the heaviest residues of chlorinated hydrocarbons. This is because these chemicals are
soluble in fat. Residues on fruits and vegetables tend to be somewhat less. These are little
affected by washing—the only remedy is to remove and discard all outside leaves of such
vegetables as lettuce or cabbage, to peel fruit and to use no skins or outer covering whatever.
Cooking does not destroy residues.
Milk is one of the few foods in which no pesticide residues are permitted by Food and Drug
Administration regulations. In actual fact, however, residues turn up whenever a check is made.
They are heaviest in butter and other manufactured dairy products. A check of 461 samples of
such products in 1960 showed that a third contained residues, a situation which the Food and
Drug Administration characterized as ‘far from encouraging’. To find a diet free from DDT and
related chemicals, it seems one must go to a remote and primitive land, still lacking the
amenities of civilization. Such a land appears to exist, at least marginally, on the far Arctic
shores of Alaska— although even there one may see the approaching shadow. When scientists
investigated the native diet of the Eskimos in this region it was found to be free from
insecticides. The fresh and dried fish; the fat, oil, or meat from beaver, beluga, caribou, moose,
oogruk, polar bear, and walrus; cranberries, salmonberries and wild rhubarb all had so far
escaped contamination. There was only one exception—two white owls from Point Hope
carried small amounts of DDT, perhaps acquired in the course of some migratory journey.
When some of the Eskimos themselves were checked by analysis of fat samples, small residues
of DDT were found (0 to 1.9 parts per million). The reason for this was clear. The fat samples
were taken from people who had left their native villages to enter the United States Public
Health Service Hospital in Anchorage for surgery. There the ways of civilization prevailed, and
the meals in this hospital were found to contain as much DDT as those in the most populous
city. For their brief stay in civilization the Eskimos were rewarded with a taint of poison. The
fact that every meal we eat carries its load of chlorinated hydrocarbons is the inevitable
consequence of the almost universal spraying or dusting of agricultural crops with these
poisons. If the farmer scrupulously follows the instructions on the labels, his use of agricultural
chemicals will produce no residues larger than are permitted by the Food and Drug
Administration. Leaving aside for the moment the question whether these legal residues are as
‘safe’ as they are represented to be, there remains the well-known fact that farmers very
frequently exceed the prescribed dosages, use the chemical too close to the time of harvest,
use several insecticides where one would do, and in other ways display the common human
failure to read the fine print.
Even the chemical industry recognizes the frequent misuse of insecticides and the need for
education of farmers. One of its leading trade journals recently declared that ‘many users do
not seem to understand that they may exceed insecticide tolerances if they use higher dosages
than recommended. And haphazard use of insecticides on many crops may be based on
farmers’ whims.’ The files of the Food and Drug Administration contain records of a disturbing
number of such violations. A few examples will serve to illustrate the disregard of directions: a
lettuce farmer who applied not one but eight different insecticides to his crop within a short
time of harvest, a shipper who had used the deadly parathion on celery in an amount five times
the recommended maximum, growers using endrin—most toxic of all the chlorinated
hydrocarbons—on lettuce although no residue was allowable, spinach sprayed with DDT a
week before harvest. There are also cases of chance or accidental contamination. Large lots of
green coffee in burlap bags have become contaminated while being transported by vessels also
carrying a cargo of insecticides. Packaged foods in warehouses are subjected to repeated
aerosol treatments with DDT, lindane, and other insecticides, which may penetrate the
packaging materials and occur in measurable quantities on the contained foods. The longer the
food remains in storage, the greater the danger of contamination.
To the question ‘But doesn’t the government protect us from such things?’ the answer is, ‘Only
to a limited extent.’ The activities of the Food and Drug Administration in the field of consumer
protection against pesticides are severely limited by two facts. The first is that it has jurisdiction
only over foods shipped in interstate commerce; foods grown and marketed within a state are
entirely outside its sphere of authority, no matter what the violation. The second and critically
limiting fact is the small number of inspectors on its staff—fewer than 600 men for all its varied
work. According to a Food and Drug official, only an infinitesimal part of the crop products
moving in interstate commerce—far less than 1 per cent—can be checked with existing
facilities, and this is not enough to have statistical significance. As for food produced and sold
within a state, the situation is even worse, for most states have woefully inadequate laws in this
field. The system by which the Food and Drug Administration establishes maximum permissible
limits of contamination, called ‘tolerances’, has obvious defects. Under the conditions
prevailing it provides mere paper security and promotes a completely unjustified impression
that safe limits have been established and are being adhered to. As to the safety of allowing a
sprinkling of poisons on our food—a little on this, a little on that—many people contend, with
highly persuasive reasons, that no poison is safe or desirable on food. In setting a tolerance
level the Food and Drug Administration reviews tests of the poison on laboratory animals and
then establishes a maximum level of contamination that is much less than required to produce
symptoms in the test animal. This system, which is supposed to ensure safety, ignores a
number of important facts. A laboratory animal, living under controlled and highly artificial
conditions, consuming a given amount of a specific chemical, is very different from a human
being whose exposures to pesticides are not only multiple but for the most part unknown,
unmeasurable, and uncontrollable. Even if 7 parts per million of DDT on the lettuce in his
luncheon salad were ‘safe’, the meal includes other foods, each with allowable residues, and
the pesticides on his food are, as we have seen, only a part, and possibly a small part, of his
total exposure. This piling up of chemicals from many different sources creates a total exposure
that cannot be measured. It is meaningless, therefore, to talk about the ‘safety’ of any specific
amount of residue.
And there are other defects. Tolerances have sometimes been established against the better
judgment of Food and Drug Administration scientists, as in the case cited on page 175 ff., or
they have been established on the basis of inadequate knowledge of the chemical concerned.
Better information has led to later reduction or withdrawal of the tolerance, but only after the
public has been exposed to admittedly dangerous levels of the chemical for months or years.
This happened when heptachlor was given a tolerance that later had to be revoked. For some
chemicals no practical field method of analysis exists before a chemical is registered for use.
Inspectors are therefore frustrated in their search for residues. This difficulty greatly hampered
the work on the ‘cranberry chemical’, aminotriazole. Analytical methods are lacking, too, for
certain fungicides in common use for the treatment of seeds—seeds which if unused at the end
of the planting season, may very well find their way into human food.
In effect, then, to establish tolerances is to authorize contamination of public food supplies with
poisonous chemicals in order that the farmer and the processor may enjoy the benefit of
cheaper production—then to penalize the consumer by taxing him to maintain a policing
agency to make certain that he shall not get a lethal dose. But to do the policing job properly
would cost money beyond any legislator’s courage to appropriate, given the present volume
and toxicity of agricultural chemicals. So in the end the luckless consumer pays his taxes but
gets his poisons regardless. What is the solution? The first necessity is the elimination of
tolerances on the chlorinated hydrocarbons, the organic phosphorus group, and other highly
toxic chemicals. It will immediately be objected that this will place an intolerable burden on the
farmer. But if, as is now the presumable goal, it is possible to use chemicals in such a way that
they leave a residue of only 7 parts per million (the tolerance for DDT), or of 1 part per million
(the tolerance for parathion), or even of only 0.1 part per million as is required for dieldrin on a
great variety of fruits and vegetables, then why is it not possible, with only a little more care, to
prevent the occurrence of any residues at all? This, in fact, is what is required for some
chemicals such as heptachlor, endrin, and dieldrin on certain crops. If it is considered practical
in these instances, why not for all?
But this is not a complete or final solution, for a zero tolerance on paper is of little value. At
present, as we have seen, more than 99 per cent of the interstate food shipments slip by
without inspection. A vigilant and aggressive Food and Drug Administration, with a greatly
increased force of inspectors, is another urgent need. This system, however—deliberately
poisoning our food, then policing the result—is too reminiscent of Lewis Carroll’s White Knight
who thought of ‘a plan to dye one’s whiskers green, and always use so large a fan that they
could not be seen.’ The ultimate answer is to use less toxic chemicals so that the public hazard
from their misuse is greatly reduced. Such chemicals already exist: the pyrethrins, rotenone,
ryania, and others derived from plant substances. Synthetic substitutes for the pyrethrins have
recently been developed, and some of the producing countries stand ready to increase the
output of the natural product as the market may require. Public education as to the nature of
the chemicals offered for sale is sadly needed. The average purchaser is completely bewildered
by the array of available insecticides, fungicides, and weed killers, and has no way of knowing
which are the deadly ones, which reasonably safe.
In addition to making this change to less dangerous agricultural pesticides, we should diligently
explore the possibilities of nonchemical methods. Agricultural use of insect diseases, caused by
a bacterium highly specific for certain types of insects, is already being tried in California, and
more extended tests of this method are under way. A great many other possibilities exist for
effective insect control by methods that will leave no residues on foods (see Chapter 17). Until a
large-scale conversion to these methods has been made, we shall have little relief from a
situation that, by any commonsense standards, is intolerable. As matters stand now, we are in
little better position than the guests of the Borgias.
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