ULTRA-VIOLET LIGHT IN HEALTH AND DISEASE
That both the compound rays of ordinary sunlight and ultra-violet rays
(“artificial sunlight”) are highly effective in the treatment of a
number of complaints is now well known. They are both in general use
for the external treatment of rickets, tuberculosis, and a number of
other diseases. Light-rays are also applied to hasten the healing of
wounds.
The use of the sun as a healing agent seems first to have been
developed in a scientific way by Dr. Neils R. Finsen, a young Danish
physician who was later awarded the Nobel Prize in Medicine. His
original researches were undertaken toward the end of the 19th century.
Then Dr. Rollier opened the first sunlight clinic in 1903, and in 1910
established his school at Leysin, in the Alps. Dr. Rollier is now
treating about 1,000 patients, mostly afflicted with various forms of
tuberculosis of the bone. The sun cure is also used to some extent for
pulmonary tuberculosis, and with considerable success. (See my _Man’s
Debt to the Sun_, Little Blue Book No. 808, Chapter IV.)
According to Dr. Rollier, exposure of the diseased to the sun’s rays is
efficacious in the treatment of anemia, malnutrition, bone and gland
infections and various types of tuberculosis, and is a body builder for
convalescents. On the outskirts of San Rafael, California, is a novel
sun sanitarium, Helios Sanitarium, modeled after the Alpine sanitaria
of Dr. Rollier.
Two investigators have recently studied the comparative germ-destroying
power of the blood in healthy and ill persons, before and after
exposure to sunlight. It was found that the germ-killing power of the
blood was increased when the sun bath lasted for a certain length of
time. It was shown that too long or too short an exposure decreased the
blood’s power. It was decreased also in patients who had fever. Several
other conditions were found to influence the results. Physicians
believe that several points of practical value may emerge from these
experiments. One important and useful result is that they offer a new
method to guide and gauge the effects of treatment in tuberculosis and
other diseases.
The practice of X-ray treatment (since 1910 included under the more
general term _radiotherapy_) includes treatment not only by X-rays,
but also by all kinds of rays—treatment by heat, by the sun’s rays, by
ultra-violet rays, and even by violet rays. The rays of radioactive
substances used in medicine come under the etymological term of
radiotherapy. But in general practice, amongst radiologists, the term
is applied to treatment by X-rays alone. Nevertheless, it is now well
established that the ultra-violet rays are not only bactericidal, but
that they also play an important role in the treatment of certain
diseases, and in the maintenance of good health. On the other hand,
these rays produce a certain irritability among persons of the white
race in the tropics, which cannot be regarded as healthful in their
general effects.
Since the amount of ultra-violet light coming from the sun has been
shown by Abbott to be variable, it may be that some of the irritability
which seems to be general among the inmates of our public institutions
on certain days is due to this change in the sun’s outpour of
ultra-violet radiation. As Dr. E. E. Free remarked not long ago:
“Put these facts together. Ultra-violet rays affect life. The amount of
ultra-violet coming from the sun is variable. Does this mean that some
of the obscure, day by day variations of health can be due to this?
Some days everybody seems happy and cheerful. Other days everybody
is depressed. Still other days are breeders of ‘nerves.’ Maybe the
ultra-violet does it. Maybe not. Doubtless the investigators will find
out presently.”
Recent experiments at the Maine Agricultural Experiment Station,
conducted under the direction of Dr. John W. Gowen, have led to the
important discovery that milk from cows that have been treated with
ultra-violet light, from mercury-vapor quartz lamps, contains a much
larger amount of the substance—presumably a vitamine, or vitamines—that
prevents rickets in children and young animals. At any rate, it was
found that the milk from cows deprived of sunlight and ultra-violet
light was quite deficient in the anti-rachitic factor. Animals and
birds fed on the sunless milk uniformly developed rickets.
The Holstein-Friesian cows used in the experiments were of nearly the
same age and calving date and all received like treatment as to feed,
temperature, etc., and stood side by side in the same barn. “Throughout
the treatment,” says Dr. Gowen, “these cows did not leave the barn. For
one month none of the cows received ultra-violet light. For the second
month two cows received ultra-violet light 15 minutes a day, generated
from a Cooper-Hewitt alternating current light at three feet above
their backs. For the third month these cows received ultra-violet
light for 30 minutes a day under the same conditions. In the meantime
Rhode Island Red chickens were allowed to develop rickets, shown both
clinically and by X-ray photographs. They were divided into two lots,
one lot of these chickens receiving milk from the ultra-violet cows,
the other of two lots of chickens, milk from the control cows. Both
lots received all the milk they wished.
The chickens have now been under treatment 50 days. The lot receiving
milk from cows exposed to ultra-violet light are in good condition
with no appearance of rickets in X-ray plates. The lot receiving
normal milk has moved progressively toward more extreme clinical
and X-ray rickets. The experiment was repeated, using the milk from
these same cows on White Leghorn chickens showing clinical and X-ray
rickets. Five chickens were in each lot. After 38 days’ treatment four
of the lot receiving milk from the ultra-violet cows are almost cured
of rickets, showing only a very slight stiffness. The fifth chicken
shows some stiffness. Four of the lot receiving the normal milk show
constantly increasing symptoms of the more advanced stages of clinical
rickets.
These results point to the conclusion that more of the substance
necessary to cure rickets is absorbed by the cow exposed to
ultra-violet light and secreted by her in her milk. The cows
prevented from receiving ultra-violet light are not able to secrete
this anti-rachitic substance in sufficient quantities to cure or
allay the process of clinical rickets. The results thus point to an
environmental factor transmitted by the cow to her offspring through
the medium of her milk. They further suggest that the high incidence
of rickets in children during the late winter months is due to their
mothers not receiving ultra-violet light either during pregnancy or
while in lactation. Furthermore, it would appear that cows’ milk
produced especially for baby-feeding should be from cows which have
access to ultra-violet light either from the sun or from some other
source.
Dr. C. C. Little of the University of Maine, and his associates, fully
demonstrated the value of sunlight to animal life through experiments
on a flock of 233 chicks. The chicks were divided into three groups and
all were given the same diet. One group was kept in natural sunlight,
the second was kept in sunlight that went through window glass, and
the third was given both natural sunlight and extra ultra-violet rays
produced artificially. The last class grew the best. The class that got
only natural sunlight grew normally. The class kept behind window glass
all developed bone disease. The glass of the greenhouse allowed the
light of the sun and the heat of infra-red rays to get through. But it
screened out the ultra-violet waves.
The beneficent effects of invisible ultra-violet rays are seen in
both the organism exposed to them and the food consumed. This is true
whether the rays come direct from the sun or by means of a quartz lamp.
Ordinary glass lamps prevent the ultra-violet rays from passing out.
But not all kinds of foodstuffs by any means are favorably affected by
the rays. Only those foods which contain fat seem to be materially
improved. The value of milk and of cod liver oil is greatly enhanced by
exposure to the rays. Dr. Benjamin Kramer has been highly successful in
treating babies affected with rickets by subjecting milk itself to the
action of ultra-violet light.[3]
As early as 1923, it had been shown by feeding experiments with
various types of animals at the University of Wisconsin that sunlight
was acting either directly upon the animal or upon its food. The
same dietary was found to produce contradictory results. It was
established—especially by H. Steenbock and E. B. Hart—that sunlight is
indispensable to man and beast, in that it is the determinant of the
efficiency with which calcium can be assimilated and retained. (See
their report, _Journal of Biological Chemistry_, Vol. 62, page 577,
1925.) Calcium, it is pointed out, needs to be conserved because in
proportion to the body needs it is not found abundantly in foods and
feeds. Steenbock and Hart tell us that sunlight plays the particular
rôle of conservator “by virtue of its content of ultra-violet
radiations of approximately 250 to 302 millimicrons in wave-length,
but unfortunately these are not present in sufficient degree to provide
a wide margin of safety for the animal. As a result we have rickets
in the young and poor dentition, restricted lactation, abortion and
impoverishment of the skeleton in lime to a dangerous extent in the
adult.... The ultra-violet rays bring their effect through the medium
of certain compounds widely distributed in plant and animal tissue, so
that practically any foodstuff can be ‘anti-rachitically’ activated.
‘Make hay while the sun shines’ is more than a mere poetic slogan,
for hay made in the dark is devoid of rickets-preventing properties”
(_Science_, December 4, 1925).
The careful experiments of J. S. Hughes showed that chickens receiving
a standard scratch feed and mash, supplemented with sprouted oats and
buttermilk, developed rickets (weak legs) when deprived of direct
sunlight. Chicks receiving the same feed but given sun baths developed
normally, although they were confined in a very small pen, with little
opportunity to exercise. Light from ordinary electric bulbs had very
little, if any, beneficial action. Light from the Hereus mercury arc
lamp was very beneficial. Cod liver oil also proved to be effective in
preventing rickets in chickens as in mammals.[4]
That such fats as olive oil and lard may be activated by exposure
to ultra-violet rays and used as a substitute for cod liver oil in
the treatment of rickets is evidenced by experiments reported by the
Department of Agricultural Chemistry of the University of Wisconsin.
In the series of experiments now published, olive oil and lard were
exposed to the action of the ultra-violet rays from a powerful
mercury-vapor quartz lamp, for periods of time ranging from half an
hour to 17 hours.
After exposure to the rays these fats were fed to a group of
experimental rats in which rickets had been produced, and the activated
olive oil and lard were found to have the same beneficial results
that follow the administration of cod liver oil. The weight of the
rats increased and an analysis of the bones showed an increase in the
calcium content.
Some of the activated olive oil, which had been stored in a stoppered
bottle, showed no change in potency ten months later. It was found
also that the fats might be activated by the rays from the open carbon
arc, the iron arc, and sunlight; but that exposure for such prolonged
periods as 17 hours destroyed their potency. This destruction took
place even on cod liver oil.[5]
It has long been known that human tissue is more actively changed by
light when it has been “sensitized.” Quinine, esculin, fluoresceine,
etc., are examples of tissue sensitizers, in addition to their
other effects. The most powerful of all known sensitizers is
haemato-porphyrin—or simply “porphyrin.” This sensitizer is a purple
substance closely allied to the haemoglobin that gives blood its red
color. Subtracting its iron and albumin from haemoglobin by appropriate
chemical processes leaves porphyrin. This substance reacts strongly to
the ultra-violet rays, in rare cases causing a disease which turns the
teeth to a deep purple hue. Victims of this uncommon ailment have to
wear gloves constantly, and when going out of doors during the day time
must put on heavy veils.[6] Porphyrin is capable of dissolving the red
corpuscles of the most dissimilar animals in the presence of sunlight.
But neither the haemato-porphyrin nor the light alone is capable of
injuring the animals. Only the combined effect of the two can harm
them. A physician experimentally injected an exceedingly minute
quantity into himself and then exposed himself to a moderate light, and
became very ill.
Hausmann found that even the diffused sunlight of an early spring
day in Vienna was sufficient to cause the death of white mice which
had been subjected to small quantities of this strange substance.
Dr. E. C. Van Leersum, of Holland, proved by experiments with rats
that the utilization of lime by our bodies can be controlled almost
at will by this “sensitization” process. Rickets, or a condition
indistinguishable from rickets, can be produced or cured by proper
control of the sensitization.
SUNLIGHT AND INFANTILE PARALYSIS
An article by Science Service, quoted in _Science_, September 11, 1925,
says:
Another of the dreaded diseases of childhood, infantile paralysis,
which, like rickets, graduates large quotas of cripples, has responded
to the good influence of the sun’s rays. Dr. G. Murray Levick, medical
director of the Heritage Craft Schools at Chailey, Sussex (England),
who originated the treatment, said that no other method has ever had
as good results as this in the treatment of infantile paralysis.
Dr. Levick first deduced that neurasthenia in grown-ups and rickets
in the young are due to the same cause. Both these diseases, he
claims, are nutritional disturbances of the nerve centers affecting
the bones in the young, and the nervous systems in the old. The action
of sunlight on the skin forms a substance which is carried into the
blood and feeds the nerve centers as well as the bones. His success in
treating neurasthenia with sun’s rays led him to apply it to cases of
infantile paralysis, a disease which is a severe shock to the nervous
system and which results in muscular atrophy. Under the action of
sunlight a renutrition of nerve centers takes place.
Synthetic sunlight produced by him with an electric arc light of his
own invention proved as good as natural sunlight, and could be better
regulated to the patient’s endurance. He used two distinct kinds of
light-rays, the short ultra-violet rays for nerve nutrition, and the
long red and infra-red rays for muscle treatment. Red rays, as can
be seen when the hand is held up against the sunlight, penetrate
the flesh to a considerable extent, and can therefore stimulate the
sleeping muscle.
Dr. Levick warns that immediate success must not be expected. He has
found constant improvement where short daily treatments were continued
over a period of several years. While the method may not be effective
in extreme cases, it is nevertheless a test which will soon show after
a few treatments whether any rejuvenation of the nerve fiber is taking
place.
It is now admitted that the (red) heat-waves may play some part in
heliotherapy—exposure to direct sunlight for medical purposes. Dr.
Lazarus-Barlow, Professor of Experimental Pathology in the University
of London, concludes that even though heat-rays may also play some
part in curative processes, “experience of the treatment of wounds by
sunlight in France during the World War indicated that a degree of
benefit arises from exposure to sunlight which cannot be attributable
to warmth and ultra-violet rays. On the other hand, in the Finsen light
treatment of lupus (a tubercular affection of the skin of the face,
occurring in several forms) and in the treatment of tuberculosis at
high altitudes, ultra-violet rays play a predominant part.”
As the ultra-violet rays penetrate but a fraction of a millimeter into
the epithelium, “it is uncertain how the rays act.” The suggestion is
here ventured that since the recently discovered Millikan Rays are
particularly powerful under the same conditions that make application
of the ultra-violet rays practicable as a therapeutic agency, it may
later be found that these highly penetrating rays, of exceedingly short
wave length, aid greatly in effecting some of the cures now attributed
wholly to the longer (and less penetrating) ultra-violet rays or the
much shorter X-rays.[7]
Professor Lazarus-Barlow calls attention to the fact that it is
precisely those tubercular persons who tan easily who are said to
derive the greatest benefit from a sojourn at high altitude.
Very remarkable is a recently adopted machine which “pours ultra-violet
light through a funnel down the throat of a patient.” The new
apparatus, first used in London, is employed for treatment of various
mouth and throat diseases, “thus making it possible for patients to
take internal baths of artificial sunlight” (_Science_, February 26,
1926).
In England, where the sky is so often overclouded, it is natural that
much attention has been given to ultra-violet ray therapy. A recent
press dispatch tells us:
“London recently had 23 consecutive days on which no beam of the sun
could force its way through the mantle of cloud and fog which spread
over that section of England. Now the Britons are making artificial
suns that may be available for both indoor and outdoor illumination.
Arc lights throwing powerful ultra-violet rays are being installed in
beauty shops and hotels, and patrons are given opportunity to bathe
their bodies in this brilliance. These rays are being billed as more
potent than sun baths, and citizens who have small chance to see the
orb of day get their sunshine and their medicine at one swoop.”
Two Indian scientists, S. S. Bhatnagar and R. B. Lal, of the University
of the Punjab, Lahore, discovered in 1925 that germs grow faster
when exposed to “polarized” light than to ordinary light. (Ordinary
light—according to the undulatory theory—is due to vibrations
transverse to the direction of the ray, but varying so rapidly as
to show no particular direction of their own, the fronts of the
light-waves crisscrossing at all angles. When, by any means, these
vibrations are given a definite direction, the light is said to be
_polarized_, the fronts of the waves being all arranged in the same
direction, though the path of the rays may be plane, elliptical,
circular, or rotary, according to the method of polarization employed.)
The Indian experimenters took cultures of the germs of typhoid fever
and cholera, and exposed one set to ordinary light, and another to a
beam of polarized light. The latter multiplied much faster than did the
germs under ordinary light.
It was demonstrated in 1925 by Dr. Elizabeth S. Semmens, of Bedford
College, London, that the digestion of starch takes place more readily
under polarized light than in ordinary light.
Prolonged exposure to the ultra-violet rays will destroy any germs
known to science. (Cathode rays—which are shorter than ultra-violet
rays—will kill not only germs, but insects as well, by means of a
device developed by Prof. W. D. Coolidge.)
“Bacteria,” says Dr. Coolidge, “have been rayed, and an exposure of
a tenth of a second has been found sufficient to kill even highly
resistant bacterial spores. Fruit flies, upon being rayed for a small
fraction of a second, instantly showed almost complete collapse, and in
a few hours were dead.”
This may lead to the application of cathode rays as a germicide, but
their effect on higher forms of life shows that their unskilled use
would be most dangerous. For example, Dr. Coolidge relates:
“The ear of a rabbit was rayed over a circular area one centimeter
in diameter for one second. After several days a scab formed which
fell off a few days later, taking the hair with it. Two weeks later a
profuse growth of snow-white hair started which soon became much longer
than the original gray hair. Another area was rayed for 50 seconds. In
this case, scabs developed on both sides of the ear, which scabs later
fell out, leaving a hole. The edge of this hole is now covered with
snow-white hair.”
A very interesting problem to scientists relates to the question as
to whether or not insects are color-blind. It may be that we now have
at least a partial answer to this vexed question, and in terms of
ultra-violet radiations.
Dr. Frank E. E. Germann, of Cornell University, calls attention to some
recent experiments which show conclusively that at least one kind of
insects (flies) have a range of vision in the ultra-violet, just as
we have in the visible spectrum. It was also made “perfectly evident
that flowers do have their characteristic ultra-violet radiations”
(_Science_, March 26, 1926, page 325). It is due “to our own egotism
that we call the insect color-blind.”
A given type of insect might in reality be visiting flowers of the
same color as far as it was concerned, while to us it appeared to
be visiting flowers of all colors. “Might not two flowers, one red
and one blue, both give out the same group of wave lengths in the
ultra-violet, and thus be identical in color to an insect seeing only
the ultra-violet? Moreover, what is to prevent two different kinds of
red flowers from giving out two entirely different sets of wave lengths
in the ultra-violet, and thus appearing to have entirely different
colors to an insect?”
In a very real sense, science is only at the beginning of the
discoveries it will yet make in its investigations of the nature and
action of ultra-violet, cathode and X-rays.
FOOTNOTES:
[3] It is interesting to note in this connection that Kuzelmass and
McQuarrie have suggested that oxidation of cod liver oil gives rise to
ultra-violet radiation. (See _Science_, September 19, 1924.)
[4] Paper read before the 66th meeting of the American Chemical
Society, held in Milwaukee, Wis., September 10th to 14th, 1923.
[5] Dr. Harriette Chick and her co-workers of the Vienna University
Child Clinic discovered, first, that the action of cod liver oil on
the bone-lesions of rickets has an exact parallel in that of the
ultra-violet rays of sunlight, or of the rays from a mercury-vapor
quartz lamp; and, second, that the oil and the rays were effective
substitutes the one for the other. See my _Man’s Debt to the Sun_,
Little Blue Book No. 808, page 49.
[6] The only creature that has porphyrin as part of its normal
body-covering is a tropical bird called the touraco, parts of whose
feathers are dyed a brilliant red by a porphyrin-copper compound known
as turacin. This pigment is remarkable also because it seems to be the
only normal occurrence of copper as a coloring compound in feathers or
skin. Turacin is soluble in weak alkali, so that when it rains and the
bird comes into contact with such alkaline solutes as frequently occur
in nature, the turacin bleaches out! Although porphyrin is rare as a
normal coloring in adult animals, it is the commonest pigment found in
the shells of birds’ eggs. Almost all eggs, from the hen’s brown to the
robin’s blue, contain it.
[7] The length of the very short X-rays was accurately determined by a
new method developed by Compton and Doan in 1925, and was found to be
about three billionths of an inch.
Transcriber’s Notes
pg 19 Changed: In March, 1923, Dr. I. Seth Hirsh
to: In March, 1923, Dr. I. Seth Hirsch
pg 42 Changed: unable to refer to their soure
to: unable to refer to their source