Document dDmoqBpJVQkNKGg3E4Op1z89
FILE NAME: Oil Industry and American Petroleum Institute (API)
DATE: 1941 Oct
DOC#: API175
DOCUMENT DESCRIPTION: The Medical Bulletin Article - Occupational Eye Hazards with Special Reference to Hazards Other than from Foreign Bodies and Traumatic Injury
THE MEDICAL BULLETIN
Vol. 5
OCTOBER, 1941
No. 2
EDITORIAL
CONTENTS
The Industrial Medical Service of the Standard Oil Company/of New Jersey and Affiliated Companies. . . 92 Review of June 1941 Issue of THE MEDICAL BULLETIN
The Necessity of Accurate Records on Hospital Cases. . 95
(Spanish Translation)
A. W. Schoenleher, M.D.
The Tuberculosis Program of Standard Oil Company
(New Jersey)........................................
99
James M. Adams, M.D.
The Use of Yaccine in the Prevention of Epidemic Influenza ............................................. 106 Rohert C. Page, M.D.
The Medical Department's Role in the Education of
Employees' Children ...............................
115
Felipe Ovalle, M.D.
Study of Physical Examinations of Employees of Compania
Nativa de Petroleos, S. A.
EnriqueA. Puzzi, M.D. (English)
122
(Spanish)
135
Occupational Eye Hazards with Special Reference to Hazards Other than from Foreign Bodies and Traumatic I n j u r y .............................................. 148 Roy S. Bonsib, M.A., E.M.
Epidemic Conjunctivitis...............................
169
J. Thomas Diaz, M.D.
Prohlems of the Visiting N u r s e ..................... 173 Anna M. Callahan, R.N.
Staff N e w s ............................................ 176
disminuira
3, elevando
In las otras
"T" al lado idica que el , al anotar
de sfilis f+" indica un gente.
MEDICAL BULLETIN
lI(-8
OCCUPATIONAL EYE HAZARDS WITH SPECIAL REFERENCE TO HAZARDS OTHER THAN FROM FOREIGN BODIES AND TRAUMATIC INJURY
THEIR OCCURRENCE, EFFECTS ON THE EYES AND NECESSARY PROTECTIVE MEASURES 4
Roy S. Bons lb, M.A., E.M. New York, New York.
Introduction
Industry, in its efforts to obtain maximum efficiency for its national defense effort, must recognize that "eye crip ples may become unwitting saboteurs," Doctor Hedwig S. Kuhn told the Industrial Nursing Section meeting of the recent National Safety Congress in Chicago.
Industrial efficiency now demands the utmost of human ef ficiency, consequently, since vision is essential to human efficiency, the early recognition of occupational eye hazards and the prompt provision of protective measures is of prime importance.
Score of this Discussion
Eye injuries occur over a wide range of industrial occu pations, and virtually none are exempt unless adequate mea sures of prevention are in effect. The most frequent cause Of eye damage is the direct injury produced by foreign mater ials such as solids and corrosive substances such as acids or alkalies entering the eyes. Accidental injuries occur accord ing to the kind of work done, though they may be classified as contusions, punctures, incisions and lacerated wounds with _ Or without infection, and the presence or absence of foreign 'bodies; and burns of the various structures of the eyes and
|i-it8 surrounding area. (3) Since these types of eye injury or
damage are generally recognized and have been discussed fre quently and voluminously, they will be excluded from this ^iBcussion. Although not as prevalent, there are other seri|OUB occupational eye hazards, which, unfortunately have not geceived adequate consideration. It is important to recogplze the fact that poisonous dusts, gases and vapors may
resented at the Session on "PROTECTION FOR THE EYES OF WORKIN INDUSTRY"-12th Annual Greater New York Safety Conven-
|On and Exposition-New York,N.Y. Hotel Pennsylvania b/Q^/kl
149
MEDICAL BULLETIN
directly or systemically affect the eyes and vision; that
radiant energy in the form of ultra-violet rays, may damage the eyes of the industrial
that and infra-rea worker:
certain parasitic and Bacillary diseases may affect the ey
that and produce damage of this delicate organ; and finally
lack of proper illumination may produce Miners' Nystagmus Si
e ffo r t and other diseases of the eye due probably to unusual
as a result of abnormal physiological condition.(4)
Due to time .limitations it will not he possible to discuss
all of these occupational eye hazards; neither will it be
possible to discuss those war gases and war materials which
have a marked effect on the eyes, such as chloracetophenone,
and which industry will probably be called upon to produce
within the next few months. However, we shall attempt to
briefly consider some of the more commonly encountered haz
ards, especially those from a few of the extensively used
industrial poisons; because the growing use of poisonous
chemicals in industry now presents one of the most serious
hazards to the eyes of workers.(5) This hazard is aggravat
ed by the fact that thousands of men and women who are work
ing with these poisons, are wholly unaware of that fact,
wholly unaware of the disease hazards to which they are ex
posed, and unaware of the steps they should take to guard
against the harmful effects of these poisons. Some attention
will also be devoted to the eye hazards produced by weld
ing operations due to the widespread and ever increasing
use of this process.
****
DISTINCTION BETWEEN OCCUPATIONAL DISEASE AND ACUTE IN DUSTRIAL INJURY - The definition of a subacute or chronic occupational disease as distinguished from an acute indus trial injury due to a single accident has been considerably broadened by state legislatures, (l)
Effects of Gases, Vapors, Fumes and Dusts in the Eyes
Toxic gases, vapors, fumes and dusts are met in a great many industries, both casually and as a constant menace to the eyes. They are encountered notably in chemical, acid, alkali, and solvent manufacturing and handling plants in textile industries involving the production of artificial silk, bleaching and dyeing, singeing in print works, in
||iphur plant E w locally K b ; others,
" at 13) tiie l
a and is ex' on the oute:
y act in bothe body.
_jc&lly> caus-
f'that lines the 'cause total b. f.nerve, and ret f BBdiate effect * vision.
The effects of blood in th severe inflamm by acid vapors notably chlori being very pen hydrofluoric a Diethyl sulpha posed to them. ' Some of the been produced
fulminate of m percussion cap; have been respi junctivitis aci The basic anil: produce inflame Other aniline < and paranitroa: vitls owing to dust may cause Spicules of pi
corneal ulcer chamber of the serious injuri to corneal ope exposure to tl of the liquid
OCCUPATIONAL EYE HAZARDS
150
nd vision; that t and infra-red al worker: that ,y affect the eye and finally that Miners' Nystagmus to unusual effort .tion. (0 Dossible to discuss oher will it "be r materials which
3hlorace tophenone,
upon to produce shall attempt to
encountered hazextensively used use of poisonous the most serious lazard is aggravatromen who are work-e of that fact, rhich they are exLd take to guard ons. Some attention produced "by weldi ever increasing;
ASE AND ACUTE INihacute or chronic ; >m an acute Indus-^ i "been considerably!
Turnes
.re met in a great onstant menace bQjj in chemical, andling plants ;ion of artific^^ l print works,
sulphur plants and in smelting operations. Some of them act only locally upon the eyes, like the fumes of acids and alka lies; others, like wood alcohol act upon the eye indirectly. That is, their effect follows absorption and general poison ing and is exerted upon the retina and optic nerve and not upon the outer structures of the eye. Others, like lead, may act in "both ways, according to the mode of entrance i n to the "body. The fumes of molten lead may irritate the eye locally, causing an inflammation of the delicate membrane that lines the eyelids, or some time after absorption may cause total blindness through inflammation of the optic nerve, and retina. (6) Again they may cause temporary im mediate effect through the circulation, producing double vision.
Irritant Effects
The effects vary with the agent in operation from excess of blood in the delicate membrane that lines the eyelids to severe inflammation. Such a condition is frequently caused by acid vapors, especially hydrochloric, and by the halogens, notably chlorine arid bromine, and by ammonia; the latter being very penetrating. It may also arise from exposure to hydrofluoric acid, hydrogen sulphide and sulphur dioxide. Diethyl sulphate vapors cause eye affections to those ex posed to them. (7)
Some of the most active types of eye irritation have been produced by certain industrial dusts. Eor example, the fulminate of mercury and silver used in the manufacture of percussion caps and Christmas fire-crackers respectively have been responsible for outbreaks of a severe type of con
m junctivitis accompanied by much pain and discharge of tears. Mi
The basic aniline dyes, methyl violet in particular, may produce inflammation of the cornea as well as conjunctivitis. Other aniline compounds producing conjunctivitis are tetryl |,and paranitroaniline. Chimney-sweeps suffer from conjuncti-
1 Vitis owing to the irritation caused by the soot. Pitch
4ust may cause severe conjunctivitis in those exposed to it. spicules of pitch may penetrate the cornea, giving rise to fjOOrneal ulcer or an accumulation of pus in the anterior ,^aD*ber of the eye. The dust from grinding asphalt produces
'flous injuries to the cornea. Nitronaphthalene gives rise P O corneal opacities, either as the result of long continued g P O B u r e to the vapor, or as a result of accidental splashing
the liquid into the eye. Workers in pitch or asphalt
`1
15L
MEDICAL BTILTETTTJ
dust, especially those breaking up pitch, should be suppuJi
with goggles of the proper type. (7 )
Systemic Effects of Industrial Poisons
A large variety of industrial poisons gives rise to trahi!
sient affections manent effects.
oil of the eyesight, and some of them to pert
Various poisons may give rise to any one
more Of these conditions, depending upon the strength of
poison and duration of the exposure. Especially hazardous'
are the fumes of dinitrobenzol which is used in the manufac
ture of high explosives. produced much eye trouble
modern Other substances which formerly
have been eliminated from
processes tected by
of manufacture the wearing of
as or the operators are better pro-1
respirators and goggles, as well
by the installation of exhaust fans. Such substances are
iodoform, volatile coal tar products used in dyeing, and
arsenic, formerly used in cosmetics and in the coloring of wall papers, artificial flowers, and paints. (6)
Prominent among the group of protoplasmic poisons which
produce blindness through inflammation of the nerve behind
the eyeball, acute or chronic, are: alcohol, nicotine, car
bon disulphide, tri-chlorethylene and the arsenical com
pounds. There is another group of internal poisons which produce blindness through other forms of inflammation and
disease of the retina. Poisons of this group, instead of
acting directly on the nerve fibers affect the nerve secon
darily through contraction of the small blood vessels of the
nerve or retina, or through changes in the blood. In this
group may be found lead, quinine, cocaine, sodium salicylate,
snake, venom, silver salts, mercurial preparations, amyl ni trite and nitrous oxide gas. (8)
Toxic Amblyopias
Toxic amblyopia is a partial or complete blindness caus ed by a poisonous substance which interferes with the func tion of the retina, the optic nerve or the more central optic pathway. Every new drug used in medicine and every new chemical used in industry is a possible cause of toxic dimness of vision so that this subject is constantly growing in scope. Victims are becoming more and more compensation conscious and the ophthalmologist, in order to be fair to both employer and employee, must have a thorough understand
ing of this subject. (9)
****
aid. He supplied
isons
es rise to tranf them to per se to any one or
strength of the ially hazardous
in the manufacwhich formerly ed from m o d e m re better pro xies, as well as substances are in dyeing, and the coloring of
(6)
; poisons which le nerve behind ., nicotine, car-
arsenical com . poisons which Lnflamma tion and jup, instead o f ; :he nerve secon)d vessels of the jlood. In this r
n i-j >dium salicylate, ,;
ations, amyl
ilindness cauS"f ,rith the funori
more central ine and evel?j ause of stantly growing e compensation^ to be fair | ugh understand
OCCUPATIONAL EYE HAZARDS
152
Classification of Toxic Amblyopia
Carroll (9) divides toxic amblyopias into three groups,
X - Those caused by poisons which produce cortical or cen tral blindness, II - Those caused by poisons depressing the entire visual field, but more especially the peripheral fields, and III - Those caused by poisons depressing exclu
sively or chiefly the central visual field. (9)
"In cortical blindness there is a complete or al most complete loss of vision but the pupils react to light because the lesion is above the light center. One of the several causes of this condi tion is uremia (presence of urine constituents in the blood). Acute carbon monoxide poisoning as a cause of toxic amblyopia is a definite entity, but whether chronic carbon monoxide poisoning ever causes optic nerve damage is questionable...Com plete blindness in a person suffering from acute alcoholism whose pupils react normally to light is probably due to acute alcoholic amaurosis (blind ness occurring without any apparent injury to the eye). The prognosis (prospect of recovery) is excellent and the patient is usually well in 25 hours. It is important to differentiate this type of poisoning from methyl alcohol amblyopia.
"The second group of toxic amblyopias are those
caused by poisons depressing the entire visual
>
field but more especially the peripheral field.
Barbiturates are usually a cause of amblyopia
,, only when used in very large doses. A cause
found among makers of artificial leather, rubber
cementers, dry cleaners, engravers,lacquer makers
and vulcanizers is BENZOL (Benzene). Dinitro-Ben-
zol also may be a causative agent. Blood loss
which occurs in patients whose general health is
below par or whose red blood cell count and hemo
globin are markedly reduced sometimes causes this
condition. ...Carbon tetrachloride which is used
both for cleaning purposes and as an anthelmintic
(.remedy for worms) may be a causative poison in
some cases of amblyopia.
"Methyl alcohol is a recognized cause of optic
12
MEDICAL BULLETIN
atrophy (a wasting or diminution in size) as evi denced by the occurrence of this condition among painters who, when working in closed spaces, in _ hale the fumes of wood alcohol. The same danger exists for persons using wood alcohol in lamps...
"In the third group of toxic amblyopias are those poisons which depress, exclusively or chiefly, the central visual field. Carbon disulphide, used widely in the rayon industry and also in the preparation of rubber, explosives, hides, insecti cides and in the wool industries produces this type of amblyopia. It is usually accompanied by poly neuritis. ..and other evidences of toxemia. Lead poisoning is found to be a cause of amblyopia in patients who are compositors, plumbers, storage' battery makers and even in children who have eat en the paint from their cribs.
"Thallium which is used by women having excessive hair growths as a depilatory and in industry as a rat poison usually produces peripheral neuritis preceding any visual disturbance.
"Tobacco-alcohol poisoning is the most common and the most important toxic amblyopia seen in this country. ...Recent research has shown that it is possible for patients with this condition to con tinue smoking and drinking and recover completely providing an adequate amount of vitamin B is taken."
****
Effect of Lead
Lead poisoning, which is the greatest poison hazard in all industry may be acquired in a great many trades, is particularly liable to injure the eyes of painters, file cutters, plumbers, electro-typers, typesetters and cleaners, pottery glazers, storage battery makers, paint grinders, and makers of red, white, orange and yellow lead, makers of lead pipe, tinsmiths (solderers) and cutters of sheet lead
or various lead article manufacturers. (6) The effects of
poisoning by lead are very widespread in the body, but tend particularly to be localized in the nervous system. Inflam-
ize) as eviition among spaces, in ; same danger . in lamps...
is are those chiefly, the Lphide, used ilso in the ies, insectinces this type aied "by polyxemia. Lead amblyopia in ers, storage who have eat-
.ng excessive industry as a ral neuritis
3t common and
seen in this own that it is iition to con ver completely inB is taken."
poison hazard id; ; many trades, is* of painters, fii stters and cleaners, srs, paint grinders,
low lead, makers of
ters of sheet la
6) The effects ol
the body, but tend ous system. InflaJ
OCCUPATIONAL EYE HAZARDS
Ilk
mation of the optic nerve of one or hoth eyes is not uncom mon in chronic lead poisoning and is associated with inflam mation of the retina which may produce total "blindness. Paralysis of the ocular muscles and dimness of vision has also "been found in lead poisoning; recovery usually occurs.
(7 ) Lead causes serious central, as well as peripheral, eye
diseases, such as inflammation "back of the eyeball and paralysis. It may he inhaled in fumes, or may enter the system through the mouth.
Effect of Volatile Substances
Many volatile substances when they reach the blood through absorption may seriously affect vision acting either di rectly upon the structure of the eyes or affecting it through cerebral deficiency in quality or quantity of blood in brain vision centers. Of this group of volatile poisons, wood alcohol forms the most striking example, as it produces a l most instantaneous, and frequently, permanent blindness when
inhaled in quantities. (6) Vapors of some of the volatile
solvents are absorbed through the lungs and cause damage to the body, the eyes included. Any substance that will cause swelling due to accumulation of a fluid in the tissue of the brain and other organs will cause a similar response in the
eye tissues. This may cause dilation or constriction of the
blood vessels and if prolonged or repeated may result in damage' to the eyes. The eye is the only window through which we can actually look inside the body and see the physiological changes which are taking place as the result
of the poisonous material, not only in the eye, but elsewhere in the body, particularly in the brain.
Effect of Alcohol
The alcohol which is usually responsible for blindness is
Hethyl or "wood alcohol". Ethyl alcohol also produces
blindness through its action on the optic nerve.
However,
only chronic alcoholic individuals are likely to suffer from severe amblyopia, and even then it is well known that
Persons who combine the use of alcohol and tobacco to excess
re the most frequent victims from these poisons.
In the
Pest few years our conception of dimness of vision due to
ethyl alcohol and tobacco has been modified. Certain investi-
Betors have shown that a deficiency of the vitamin. Bp and vitamin B 2 complex in regular diet is actually responsible for
155
MEDICAL BULLETIN
found in nerve tissues, and after death the Brain retains &
large percentage of this alcohol. A highly differentiated;
nerve substance like that of the optic nerve is
particularly liable to be affected by it. (6) It
thought for a long time that wood alcohol attacks
htahserefboerene' the eyen
especially, but recent researches have demonstrated, exclu-"
in sively that this is not a special attack on the eye but that
the eye is merely indicative of the response that goes on the brain and other tissues, and that the blindness produced
or the affect on the vision is simply discerned more readily.
There is nothing so outstanding or dramatic as any effect on
the eyes.
Effect of Carbon Disulphide
ber of eye injuries occur in the rayon industry to workmen in ! the spinning room where irritations are caused by a combi nation of mist containing about eleven per cent sulphuric acid in addition to the carbon disulphide. British investi gators found that, as the result of an isolated exposure to a concentration of only one part of carbon disulphide by
volume in 3>000 parts air of a few hours duration, severe
headache and mental dullness or confusion usually result. If such exposures are of daily occurrence, the symptoms be come increasingly severe with inflammation of the nerves,
distorted vision and mental disturbances. (10)
Effect of Dinitro-Benzol
Used in manufacturing aniline dyes and the production of high explosives, injures the vision by inhalation and produces a distinct toxic effect on the vision similar in many respects to that caused by carbon disulphide. Its effects are found in varying degree in all those who suffer periodically from
OCCUPATIONAL EYE HAZARDS
156
subacute attacks of poisoning. Susceptibility may aggravate
the symptoms, but no worker can claim perfect immunity. Com paratively few complain of any impairment to their sight, but
probably about one in ten are unknowingly affected.Snell (1 1 )
In all cases absence from exposure removes these symptoms in
a varying length of time, and usually a restricted exposure
will alleviate them. (12)
Effect of Carbon Monoxide
Carbon monoxide produced by the imperfect combustion of
gasoline may be so prevalent in garages and automobile repair
shops as to produce disturbances of the optic nerve and the
retina. (13) The literature on carbon monoxide asphyxia
contains a fair number of reports of permanent damage to
vision. Drinker (1^) has found that as a rule, serious eye
injury requires severe poisoning, that is, poisoning in
which there is a long period of unconsciousness. But there
are rare cases which are exceptions to this rule.
We are
told that in most instances of visual disturbance following
carbon monoxide asphyxia, the injuries (lesions) are in the
vital part of cells of the different ocular nerves. The
effects may be permanent, as in the case of other cerebral
damage due to carbon monoxide, or they may be quite tran
sient. When permanent, they are to be distinguished from
hysterical phenomena, so often found after mild by the -presence of nervous or mental symptoms
poisoning, indicating
damage to the nervous system, or by definite lesions in the eyegrounds.
The term "chronic monoxide poisoning" as usually used,
very loosely describes the permanent after-effects of severe
exposure of an acute nature or it is used just as freely to
describe the ill health resulting from repeated minor ex posures of an acute nature but where certainly very seldom
toy symptoms remain when the exposure ceases.
*-***
jjhflaamation narked with noints or dots on or near the surface
157
MEDICAL BULLETIN
the diagnosis of acute, subacute or chronic conjunctivitis.
This condition has been found among workers with lacquers in
the furniture and metal industries, in the rayon industry
in mushroom canning, among workers in the straw hat industry
and in agricultural workers on reclaimed marsh lands in
California. Rankine (l6) who reported on 1,598 workers in
the acid house in the rayon industry, listed the symptoms aa
blurred vision and halos, grittiness, abnormal intolerance
of light, discharge of tears, eyelid muscle spasm, aching
back of the eyes and headaches. Burning and stabbing pains
increase toward the end of the day and working-week and the
symptoms are most marked during the winter months when the
ventilation of workrooms is poorest.
All writers stress
evidence of individual predisposition in the form of frequent
recurrences in some persons and immunity of other neighbor
ing workers. (15 )
The outstanding offending agents appear to be hydrogen
sulphide, principally in the rayon and sugar industries,
also mines and tunnels, benzol and similar solvents and
diluents of varnishes, shellacs and lacquers. Many writers,
such as Klein (17) and Buchlers (18) stress the effect of
drops of chemicals on the cornea, and the drops scattered
by spinning and spraying rather than the gases involved in
artificial silk industrial processes as the factor respon
sible for the eye conditions found. According to McDonald
(19)) hydrogen sulphide containing droplets of the acid bath
are responsible for keratitis among the workers in the rayon
industry] he found the condition more marked in damp weather
and stated that a concentration of ten parts per million is
permissible. Others of the important agents considered in
textbooks and in the literature are hydrogen fluoride, tar,
pitch, mercury and silver sublimate, certain kinds of wood
and lead nitrate. The victims all get well with change of
occupation, and there is complete return to health in from
seven to ten days. (15)
Occupational Dystrophy
Davidson (15) asserts that true occupational dystrophy such as is reported in textbooks and in the literature, has not been observed. Cases of dystrophies as after effects of accidents have, however, been encountered. For example, examinations prove that a degenerative process goes on in the cornea with lime incrustation in the course of years in connection with lime burns. These manifestations may be
Relayed and presen between injury and
Occi
At the 1956 mee1 Dr. Lane (20) of tl port on an occupal tear apparatus, etc patients. The cas tumors or cancers mentary deposits,
report issued (21)
in the United State where oils have a h have such high canc oils. American oi oils. Refining in process the workme of the largest oil with records extend small number of can tensively to sunligl
being exposed to knc
and tar have more tl found in all the otl to the large number mas, as well as alai growths which can e: lieved that the occi: carpenters is due tc composition roofing of building papers, to the sunlight. Pa tribution of ocular irritant and frequer A small distributioi whose occupation in\ Concentrated coal pi distillation of coal house workers show parts of the body bi from ten to fifteen
OCCUPATIONAL EIE HAZAKK3
158
delayed and present problems in the differential diagnosis between injury and disease.
****
Occupational Cancer of the Eye
At the 1956 meeting of the American College of Surgeons, Dr. Lane (20) of the University of Michigan presented a re port on an occupational study of cancer of the eye, l i d ,
tear apparatus, etc., setting forth the results on 1,000
patients. The cases were divided equally between malignant tumors or cancers and tumors characterized by abnormal ,pig mentary deposits. These studies were continued and a later
report issued (2 1 ) from which we learn that oils produced
in the United States except in the middle west oil region where oils have a higher paraffin and asphalt base, do not have such high cancer-producing properties as do foreign oils. American oils contain less sulphur than do foreign oils. Befining in the United States is largely a closed process; the workmen have little contact with the oil. One of the largest oil companies, employing thousands of workers, with records extending over many years show a surprisingly small number of cancers. Occupational groups exposed ex tensively to sunlight and the elements at the same time being exposed to known cancer-producing agents such as pitch
and tar have more than 2.8 times the total number of cases
found in all the other groups. Special attention was called to the large number of farmers and laborers having carcino mas, as well as a large number of carpenters having tumors or growths which can either be benign or malignant. It is b e lieved that the occupational hazard in the case of the carpenters is due to the handling of creosoted shingles, of composition roofing which contains much tar and asphalt, and of building papers, also other lining products in addition to the sunlight. Painters have a potentially increased dis tribution of ocular cancer. Chrome is a, decided chemical irritant and frequently enters into the composition of paint. A small distribution of ocular cancer was found among those whose occupation involved a considerable use of chemicals. Concentrated coal products such as pitch and tar derived by distillation of coal are potent cancer-producing agents. Gashouse workers show a rather high cancer incidence in other parts of the body but not in the eye. As a rule it takes from ten to fifteen years' exposure to an irritant before
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MEDICAL BULLETIN
precancerous or cancerous injuries (lesions) develop. Doctor lane's report is evidently a very interesting
statistical study of the occupational Background of a series of cases showing cancerous changes in the eyes. However, it is questionable whether the figures given make any particu lar case as to the occupational origin of these cancers. The distribution of the cancer cases among the occupations mentioned is so varied and of such low order in those occu pations having a known exposure to cancer-producing materials as compared with the cases not so exposed, it is doubtful that this study shows any particular occupation to be a cau sative factor in the location of cancer in the eye.
Effects of Heat on the Eyes
One of the moat frequently reported causes of the occupa
tional type of cataract or the crystalline lens of the eye
becoming opaque is exposure to intense heat as In the remov
al of molten material from the furnace. However, heat is
apparently being discounted more and more as a cause of cancer
per se. Grlass workers are probably the best known victims
of this type of occupational eye hazard. Mehofer (22) b e
lieves that the excessive perspiration of glass makers plays
an important part in producing this change in the lens.
A
third cause may be the brilliant white light that dazzles
workers in glass and which, by fatiguing the retina of the eye,
reflexly influences the lens. Molten iron and working near
electric and other types of furnaces expose workmen to ex
cessive heat which burn the lids and cornea and cause cata
racts and degeneration of the retina. Protective glasses and
helmets may prevent such occurrences. (23)
Effects of Radiant Energy
Radiation from an intensely heated solid or vapor may be divided into three portions: (a) invisible infra-red rays, (b) visible light rays, and (c) invisible ultra-violet rays. The presence of the infra-red rays, although they are invis ible, may be recognized by the sensation of heat which they produce on the skin. The visible light rays enable us to see; but we have no sense that detects the invisible ultra-violet rays, so we know them only by their effects. Exposure of the unprotected eyes to very intense light sources, rich in ultra violet radiant energy, produces an acute and painful inflam mation of the eyes. Long continued exposure or frequent short
OCCUPATIONAL EYE HAZARDS
16 0
exposures to ultra-violet rays of even moderate intensity may Have a similar effect on the eyes. The disease produced is a form of inflammation of the lining of the eyelids commonly
called Electric-Ophthalmia or Photophthalmia. (13) Black (24)
says that the effect upon the eyes is practically the same as a sunburn, when the unprotected body is exposed to the; sun's nays, and, like a sunburn, is not noticed until several hours after exposure. The heat radiation from work where the ra diant energy hazard exists is so great that heat insulating material is required for all parts of the protectors which touch the face of the operator.
A series of experiments have been made by the United States Bureau of Standards upon various kinds of colored glasses. It
was found that most black, amber, green, greenish-yellow and red glasses are efficient for protecting the eyes from ultra violet light. For shielding the eyes from infra-red rays: yellowish-green, sage-green, gold-plated and bluish-green glasses are the most serviceable, although color is no cri terion of efficiency. Glasses having a gray or neutral tint are the most agreeable, as they do not alter the color of ob jects. It has also been found that workmen in welding pro cesses prefer a yellowish-green glass to any other color. The cobalt glass so commonly used by furnace men is not effective
in providing protection from ultra-violet radiant energy.(25 )
In fact the cobalt blue is the least suitable color for this
protection. (13)
.
Photophthalmia
Photophthalmia is an inflammation of the conjunctiva pro
o fduced by the burning effect radiant energy.(2) It is
of the likely
harmful ultra-violet rays to develop in.workers ex
posed to intense light or heat and is quite similar to snow-
blindness. It is not a serious disease in itself but if a
person is exposed for long periods or frequent intervals, it
may lead to severe trouble. A peculiar form of this disease,
known as "Klieg Eyes", is found among'motion picture actors
to a certain extent. In this case it is caused by exposure to the intense studio lights which are rich in ultra-violet
^ys. (13)
Occupational Cataracts
continued exposure to intense slow development of cataracts.
l6l
MEDICAL BULLETIN
Because the disease is especially associated with workers in molten glass, it is commonly referred to as "Glass-Blowers' Cataract", although it has Been found to occur in other in dustries such as chain-making, smelting, tin plate making gas welding and cutting. There seems to he considerable dif ference of opinion and controversy as to whether or not cataracts may he formed from such exposure. However, it is
reported (13) that the development of a cataract, which is
an opacity of the crystalline lens, is so gradual that often the vision is reduced to one-tenth before advice is sought. Such a condition can he prevented by the continuous use of suitable goggles or other visual protective devices during
periods of exposure. (13)
Eye Hazards Due to Electric Arc Welding
There is a high localized energy discharge with emission of light and a temperature as high as 6300E. (3482PC.) in the field of an electric arc. Thus one would expect radiant energy, volatilization of materials, gaseous fixation and decomposition products, and molten metal spray to be the most serious hazards present.
****
Eye Exposure in Welding
The changes in the eye due to radiation exposure have been discussed frequently and have been ascribed to various wave lengths. The welding flame, as encountered in the course of work, presents but little, if any, exposure to either infra red or ultra-violet, but it is now believed to injure the eyes chiefly through intense glare or radiation within the visible range. The length and intensity of exposure is of course important as is the distance from the sources of radiation. It must be remembered that the sources of radia tion include not only the welder's own work, but also direct or reflected rays from neighboring workers. Lipkovitch (26)
has estimated that the welder has a potential exposure of 30 to 60 per cent of his work day from his own or his neighbor's
operation. Pozzi (27) has reported inflammation of the cornea and the lining of the eyelids due to ultra-violet
radiation occurring in an individual 30 feet lateral to the welder. The minimal safe distance has been estimated at 00
feet. (28) According to an abstract from the American
OCCUPATIONAL EYE HAZARDS
162
Journal of Ophthalmology (September, 1935), Natason states that 35 per cent of 210 welders examined had inflammation of the conjunctiva, and 203 out of 295 eyes had diminished cor
neal sensitivity.
Acute Eye Injuries Due to Ultra-Violet Rays
The usual injuries produced by ultra-violet rays from the electric arc during welding operations are typically a blepharitis (inflamination of the eyelids) and keratoconjunc tivitis. Symptoms occur from four to eight hours after ex
posure and last from 2b to U8 hours. Prolonged exposure or
secondary infection may cause prolongation of symptoms and even the development of corneal ulceration. This type of eye injury is rather common among welders and may result in the development of chronic inflammation of the lining of the eyelids. Most welders have noted a severe inflammation of the eye by rays beyond the violet of the spectrum at one time or another but have lost no time from work because of the difficulty. Tho exposure necessary to produce this con dition is variable, a mere "flash" has been reported to cause discomfort. Certainly individual susceptibility and the presence of chronic eye diseases predispose to the de
velopment of such conditions. (29)
Chronic Eye Injuries
On repeated exposure a chronic indefinitely localized in flammation of the outer layer of the sclera has been reported. Other eye conditions reported to occur as a result of welding exposure are inflammation of the retina, pigment changes in the retina, inflammation of the cornea, and even detachment of the retina. Color blindness, blind or partially blind areas in the visual field, weakness or speedy tiring of the visual organs, attended by pain in the eyes and headache, dimness of vision and other visual derangements have also been reported. Sudden intense stimulation of the unprotected eye by the welding arc may produce blindness similar to snow or ice blindness (due to ultra-violet and visible rays) or electric, eclipse or flash blindness (due to the entire spectrum, ultra-violet, visible and heat rays). These con ditions may be only temporary; however, in the case of infra red rays a permanent heat, death or destruction, of the
retina may occur. Roy (30) and Wurdemann (3 1) have reported
permanent retinal damage and blindness in individuals
163
MEDICAL BULLETIN
"5 '1 watching electric welders at a distance of a few feet with the unprotected eye.
Cataracts
The occurrence of cataracts due to exposure in welding is not easily disposed of. Opinions are divided; it is gen_ erally agreed that the shorter ultra-violet radiation does not reach the lens (some of the longer ultra-violet rays may he absorbed and produce changes in the lens proteins) and. that shorter infra-red rays do reach the lens and are trans formed into heat and may cause some damage to the lens nu trition. However, one usually finds a combination of causes such as general disease or nutritional states of the body
also may play a role.(29)
Eyestrain
Eyestrain due to fineness of the work, the diminished luminosity and sudden changes in light intensity are de
scribed in the literature.(32) Chautin (33) noted some delay
in visual adaptation in a small group of welders. Others deny that such a condition exists, and that protective screen and colored glass effectively protect the workers' eyes by absorbing ultra-violet, visible and infra-red rays as is shown in their examination of visual acuity and visual fields of many welders. They found no more abnormalities of vision
in groups of welders than is found in any average group.(29)
Other Eye Injuries
Another source of eye damage is the transference of infec tions from one worker to another by exchange of goggles and other protective equipment. Each welder should be furnished with his own visual protective equipment which must be sterilized at intervals. Equipment which has been sterilized will be much more acceptable among the workers, since goggles are a very personal piece of protective equipment and work men do not care to use such an article that has been worn by others. It has been found that giving each person his own equipment, and having it sterilized frequently, adds immeasu rably to the worker's acceptance and use of the equipment. Foreign bodies in the eyes occur not only from molten metal and slag from his own or neighboring work but also from sharp fine slag particles which break off when the 'brittle
MEDICAL B U H E TIN
itching electric welders at a distance of a few feet with le unprotected eye.
Cataracts
The occurrence of cataracts due to exposure in welding is it easily disposed of. Opinions are divided; it is genally agreed that the shorter ultra-violet radiation does it reach the lens (some of the longer ultra-violet rays may : absorbed and produce changes in the lens proteins) and tat shorter infra-red rays do reach the lens and are transirmed into heat and may cause some damage to the lens nu'ition. However, one usually finds a combination of causes ich as general disease or nutritional states of the body
.so may play a role. (29)
Eyestrain
Eyestrain due to fineness of the work, the diminished iminosity and sudden changes in light intensity are deribed in the literature.(32) Chautin (33) noted some delay . visual adaptation in a small group of welders. Others ny that such a condition exists, and that protective screen d colored glass effectively protect the workers' eyes by sorbing ultra-violet, visible and infra-red rays as is own in their examination of visual acuity and visual fields
many welders. They found no more abnormalities of vision
. groups of welders than is found in any average group.(29)
Other Eye Injuries
Another source of eye damage is the transference of infecons from one worker to another by exchange of goggles and her protective equipment. Each welder should be furnished th his own visual protective equipment which must be erilized at intervals. Equipment which has been sterilized
11 be much more acceptable among the workers, since goggles
e a very personal piece of protective equipment and workn do not care to use such an article that has been worn by hers. It has been found that giving each person his own uipment, and having it sterilized frequently, adds immeasubly to the worker's acceptance and use of the equipment, reign bodies in the eyes occur not only from molten metal i slag from his own or neighboring work but also from arp fine slag particles which break off when the brittle
OCCUPATIONAL EYE HAZARDS
161+
slag is cleaned or removed from a "bead. (29)
Protective Equipment
Because of the intensity of ultra-violet and infra-red rays from the electric arc, it is imperative for the operator and his assistant to use a hand-shield or helmet which pro tects the skin of the face and neck, and which is also equip
ped with a suitable filter lens (shades 6 to lh) that will
provide adequate eye protection. In the selection of these lenses, it is necessary to depend upon laboratory tests as the transmission of ultra-violet and infra-red radiation can not be determined by visual inspection. Depth of color does not necessarily indicate removal of the invisible rays which nay be injurious to the eyes. Reliable dealers are able to supply filter lenses which have been shown by tests to' con form to requirements of the American Standard Code (ASA Z21938) for the "Protection of Heads, Eyes, and Respiratory O r gans of Industrial Workers" (Handbook H2h, National Bureau of Standards, Washington, D.C.)
Effects of Insufficient Illumination
Perception of detail depends upon the size of the image
cast upon the retina of the eye and upon the power of accom
modation of the eye; for these reasons it is important
that the illumination should be sufficient to make all neces
sary detail not merely visible, but easily seen.
If this
cannot be done the eyes will be brought closer to the work,
with consequent eyestrain and headache may be increased. (7 )
The theory that near-sightedness may be caused by insuffici
ent illumination has been pretty well exploded. Nystagmus is
one of the most frequent and best known indirect results of
insufficient illumination.
Nystagmus
Nystagmus is the term applied to a singular twitching or constant oscillation from side to side of the eyeball, usually accompanied by considerable dimness of vision. It Is often found among workers who constantly subject their eyes to ab normal and unaccustomed motions, such as miners, painters, locomotive drivers, draughtsmen, jewelers, typists, and tex
tile workers.(3^)
165
MEDICAL BULLETIN
Necessary Eye Protective Measures
Since eye damage may be due to the direct action of 8ub^
stances such as solids or corrosive liquids, toxic gases va1*
pors or dust -which produce occupational poisonings (intoxica^
tions); ^or to various forms `of radiations orto infectious of
parasitic agents, or, finally, to fatigue and occupational
eye strain, it is obvious from a consideration of these causad
tive means that the control of toxic gases, dusts, and vapoi
in industry -will control the eye damage due to such toxic'
substances. Toxic materials in industry should therefore be
controlled by proper enclosure or isolation, ventilation anj-
substitution. Protective goggles and shields of various*
types should be provided to prevent the entrance of solid-
material into the eyes. Special types of goggles are now-
avaliable to protect the eyes from acids and alkalies and
their vapors. Protection against radiant energy, as has al
ready been indicated, may be achieved only by the use of
suitable radiation-filtering screens and goggles.
In the
case of infectious and parasitic agents, protection may be
achieved by the methods usually employed by health authori
ties against parasites of man and animals and, finally, in
the case of occupational eye fatigue and eyestrain, protec
tion may be achieved chiefly by the provision of suitable il
lumination in adequate amounts.
.
According to Resnick (35) preventive hygiene -when' toxic
substances are used in industry consists mainly of complete
cleanliness in all parts of plants -where the poisons are used
or stored. Floors, walls, machinery, clothing and skin of
exposed workmen should be thoroughly cleaned as often as
practicable. When the toxic substance is in the form of fumes
or vapors, adequate ventilating systems should be installed,
and all pipes, tanks and receptacles of any kind should be
absolutely leak-proof. Close-fitting, airtight goggles are
advisable when other means of protection cannot be employed.
When the toxic substance is a liquid, floors, should be made
of cement or of some other relatively inert material, and
should be protected by paint resistive to the liquids present.
They should also be so constructed that the liquid, escaping
from a receptacle, will not present danger to nearby workmen.
Certain employees are abnormally susceptible to certain
poisons; such workers should be transferred to other employ
ment. Men and women with respiratory diseases or skin di
seases, or who use alcohol to excess or who are generally
allergic, are usually predisposed to the harmful effects of
MEDICAL BULLE Till
Necessary Eye Protective Measures
Since eye damage may be due to the direct action of sub-
nces such as solids or corrosive liquids, toxic gases,va-
s or dust which produce occupational poisonings (intoxica-
ns); or to various forms of radiations or to infectious or
asitic agents, or, finally, to fatigue and occupational
strain, it is obvious from a consideration of these causa-
3 means that the control of toxic gases, dusts, and vapors
industry will control the eye damage due to such toxic
stances. Toxic materials in industry should therefore be
trolled by proper enclosure or isolation, ventilation and
3titution. Protective goggles and shields of various
3s should be provided to prevent the entrance of solid
srial into the eyes. Special types of goggles are now
Liable to protect the eyes from acids and alkalies and
Lr vapors. Protection against radiant energy, as has al-
Ly been indicated, may be achieved only by the use of
sable radiation-filtering screens and goggles.
In the
3 of infectious and parasitic agents, protection may be
Leved by the methods usually employed by health authori-
s against parasites of man and animals and, finally, in
case of occupational eye fatigue and eyestrain, protec-
i may be achieved chiefly by the provision of suitable il-
nation in adequate amounts.
ccording to Besnick (35) preventive hygiene when toxic
tances are used in industry consists mainly of complete
nliness in all parts of plants where the poisons are used
tored. Floors, walls, machinery, clothing and skin of
sed workmen should be thoroughly cleaned as often as
ticable. When the toxic substance is in the form of fumes
apors, adequate ventilating systems should be installed,
all pipes, tanks and receptacles of any kind should be
Lutely leak-proof. Close-fitting, airtight goggles are
3able when other means of protection cannot be employed,
the toxic substance is a liquid, floors, should be made
sment or of some other relatively Inert material, and
Ld be protected by paint resistive to the liquids present,
should also be so constructed that the liquid, escaping
a receptacle, will not present danger to nearby workmen,
rtain employees are abnormally susceptible to certain
ns; such workers should be transferred to other employ -
Men and women with respiratory diseases or skin di-
s, or who use alcohol to excess or who are generally
gic, are usually predisposed to tto
`
OCCUPATIONAL EYE HAZARDS
l66
many poisons. (35) Considerable interest is now being taken
in the psychological and psychiatric problems raised by workers having eye injuries, and especially those working under poor light. This is a most interesting problem, a satisfactory solution of which should aid in reducing eye injuries and visual impairment.
C o n e lusion
Good vision is an important factor in industrial effici ency; consequently, the protection of the eyes and the cor rection of defective vision, as well as the maintenance of lighting and ventilating conditions appropriate to the work performed is of considerable importance to industrial m a n agements. Through the organization of eye examinations and adequate treatment of injured eyes, as well as the protection of the eyes under abnormal working conditions, much can be accomplished in the protection of the health and working ef ficiency of employees, prevention of accidents, reduction of absenteeism, savings in compensation costs, and improvement in the quantity and quality of products. The full coopera tion of employers, plant physicians, plant engineers, Indus trial nurses, and department foremen is required if these
ends are to be served. (3 )
As industry comes to be held responsible more and more for the effects of the ever-growing use of poisonous materials through their designation as compensable occupational disease hazards, progressive employers will find it profitable and advisable to make use of every known means to protect their workers exposed to these poisons. Meanwhile, it is the responsibility of every safety engineer, of every physician or surgeon having any industrial practice, and of every industrial nurse, to become familiar with all the poisonous substances used in their respective plants and to take all possible steps to protect the employees who are exposed to
these poisons. (5)
( 1) ( 2)
( 3)
DAVIDSON, M. : Occupational Keratitises and Corneal
*
Dystrophsis, Arch, of Ophth. 2 1 : 673-683 (April loxll
DORIAND, W.A.N. : The American Illustrated Medical
*
Dictionary 13th Ed. W.B.Saunders Co., Philadelphia and London. (I925)
LANZA, A. J. and J. A. GOLDBERG-: Industrial Hygiene,
Oxford University Press, New York, pp 210-229.(1939VI ( 4) GREENBURG, L. : Priceless Possessions, National Safety *
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( 5) RESNICK, Louis: Fifteen Years' Progress in Eyesight
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* ' (June 1939)
I'm ) -.i n d u s t r i a l EYE HAZAR]
1
National Safety C<
?24)3LACK, N. W.: The Ey<
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the Extens. Div.,1
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H 25) NATIONAL BUR- OF STA
ard Safety Code f
and Respiratory 0
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n
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