..Abt VI 
LACRIMATORS. STERNUTATORS AND SCREENING SMOKES 
By 
Lt. Coradr. Arthur F. Abt, MC, U.S.N.R, 
Great Lakes Naval Training Station 
Lacrimators 
The lacr imator s are gases commonly known as tear gases which 
have been used in civilian life for mob control and are used for 
military training purposes. They may, however, be encountered 
in warfare because of their immediate harassing effect on the 
eyes. The lacrimators, as a group, have certain well defined 
properties in common, the most important of which are the 
following: 
1. They have the power to irritate certain tissues only, 
i.e., the eyes, and without producing noticeable 
lesions| their action is thus both elective and revens- 
ible since they affect only one organ, and the irrita- 
tion produced quickly disappears. 
2, Their threshold of action is low, i.e., they are ef- 
fective in extremely low concentrations, such as a few 
thousandths of a milligram per liter, and can produce 
an intolerable atmosphere in concentrations as low as 
one-thousandth of that required for the most effective 
lethal agents. 
3. They are quick acting, producing almost instantaneous 
physiological effects (in less than 1 minute) in the 
form of a muscular reaction of the eyelids, closing 
the eyes, and a glandular reaction from the lacrima- 
tory glands, producing a copious flow of tears. 
4, Physically, the lacrimators are, in general, liquids 
of relatively high boiling points and low vapor pres- 
sures. They are, therefore, essentially nonvolatile _ 
substances that form persistent gases, 
A marked peculiarity of the lacr imator s as a group is their rela- 
tive ineffectiveness against animals. Thus it was noted early 
in the war that concentrations which caused profuse lacrimation 
in men produced no visible effect upon horses and mu3.es. From 
careful tests, using brombonzyl cyanide as the agent, it was 
found that it was necessary to use a solution 100 times as strong 
to lacrimate a dog and 1,000 times as strong to lacrirnate a horse 
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to the same degree as a man. The reason for this great difference 
in the sensitiveness to iacrimation between men and animals has 
never been satisfactorily explained, though the fact is well es- 
tablished by tests and war experience. 
The most important lacrimators are chloracetophenone (CN), 
chloracetophenone solutions (CBS and CNB), and brombenzyl cyanide 
(CA). 
Brombenzyl cyanide was the last and most powerful lacrimator used 
in the first World War, It was introduced by the French in July, 
1918, as the culmination of their efforts to produce more powerful 
and effective lacrimators. It was also simultaneously adopted by 
the Americans as their standard lacrimator and was manufactured in 
the United States in the fall of 1918. Its persistency in the 
open is three days; in woods, seven days; and in the ground, from 
fifteen to thirty days. While brombenzyl cyanide was by far the 
most powerful lacrimator used in the last war, it has three very 
serious defectsi 
1. It corrodes iron and steel, requiring specially lined 
containers, 
2. It is not chemically stable, but slowly decomposes in 
storage. 
3. Its great sensitiveness to heat makes its use in 
artillery shell very difficult. If the bursting charge 
is not kept very small, it causes loss of the chemical 
filling through decomposition on explosion. 
Chloracetophenone. Because of the difficulties attending the use 
of brombenzyl cyanide, the Americans toward the end of the war 
began to investigate the properties of chloracetophenone as a 
combat gas. Owing to the short time it was under study in the 
war and the difficulty of its manufacture, no chloracetophenone 
was used in World War I, Shortly after the war, however, 
American investigators became convinced of its superiority as a 
tear gas and worked out a satisfactory process of manufacture. 
Unlike the lacrimators used in the last war, chloracetophenone 
is a solid, and remarkably resistant to heat and moisture. It 
does not corrode metals, including iron and steel, so it may bo 
loaded directly into shell, either by casting or pressing, with- 
out danger to the workmen handling it. In lacrirnatory power, 
chloracetophenone is about equal to brombenzyl cyanide. 
The lacrimators are classed as harassing agents, and are employed 
to cause temporary disability or discomfort, thus wearing down 
the morale and physical resistance of the enemy. By forcing the 
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use of masks, they also reduce the effectiveness of hostile forces, 
and make sleeping and rest difficult. They may be projected by 
hand grenades, artillery and mortar shell, and by airplane spray 
or bombs, hence may be used on locations far behind the forward 
line as well as against forward elements, Lacrimators may be used 
alone as harassing agents, or in some instances, with high explo- 
sive fire to assist in demoralization. 
General symptoms produced by the lacrimators include lacrimation, 
photophobia and blepharospasm, also some irritation of the nose 
and the freshly shaven face. In addition, chloracetophenone 
solutions CNS and CNB may cause some mild papulo-vesicular derma- 
titis, especially in warm weather, and occasional vomiting. 
Direct contact of the eyes with these solutions may cause perma- 
nent damage from corneal ulceration. These effects are more 
frequent and more exaggerated in warm weather and on sweaty skins. 
Men who are lacrimated do not require evacuation as casualties. 
They only need to leave the contaminated atmosphere and face the 
wind, allowing it to blow into their eyes. They should not rub 
their eyesj their clothing and equipment should be loosened so as 
to get rid of entrapped gas. Bathing the eyes in cold water or 
with a weak boric acid or sodium bicarbonate solution will aid. 
If this procedure is not possible, the mask should be put on the 
individual and rapid breathing maintained to aid removal of the 
agent from the eyes, which are kept open as much as possible. 
The vapor of the lacrimators produces a marked but self-limited 
irritation of the conjunctiva. When liquid lacrimators are 
splashed into the eye, the action is more corrosive and resembles 
the burn of a strong acid. The instillation of a solution of 
sodium sulfite (for eyes) at frequent intervals dissolves and 
neutralizes the irritating agent. 
S ter nut at or s or Irritant Smokes 
By the summer of 1917, the gas masks of all of the belligerents 
had been developed to a stage where they furnished adequate pro- 
tection against the lung-injurant gases. Also, the lung-injurant 
gases theretofore employed were slow acting and did not incapaci- 
tate until several hours after exposure. The problem was, there- 
fore, to find a quick-acting nonpersistent gas that would penetrate 
the mask, and the sternutators or irritant smokes were the solution 
of the German chemists to this problem. While the sternutators 
produced few serious casualties, by quickly penetrating the mask, 
nauseating the soldier, and causing frequent vomiting, they usually 
made it impossible to wear the mask, and upon its removal the 
soldier soon fell victim to the lung-injurant agents which were 
fired simultaneously with the sternutators. 
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As a rule, the sternutators are nonlethal in concentrations 
ordinarily employed in battle and have the following properties 
in common: 
1. Their thresholds of action are extremely low; a few 
thousandths of a milligram per liter produce certain 
and useful results. 
2. They are immediately effective; an exposure of 1 to 2 
minutes being sufficient to produce positive effects. 
3. Their action is reversible, since the irritation pro- 
duced disappears rapidly after termination of exposure. 
They do not destroy the nerve ends and, after the re- 
flexes caused by the irritation, the nerves recuperate 
their normal functions. 
4. Their action is elective, for they affect only the nerve- 
tissues and especially those controlling the respiratory 
system. 
The most important irritant smokes are Adamsite (DM) and 
Diphenylchlorarsine (DA). They produce sensory irritation of the 
nose, throat, and eyes. They may be used only in candles and hand 
grenades so may be employed only at close range. DM and DA are 
most valuable against masks with inadequate filters. Adamsite does 
not give a characteristic odor, but diphenylchlor arsine smells more 
or less like shoe polish. When not covered with a smoke screen, 
they may be recognized as thin clouds in the air. Like the lacri- 
mators, it is impossible to build up a lethal concentration of the 
sternutators except in closed spaces. 
DM and DA produce local irritation of the nose and nasal accessory 
sinuses, throat, and eyes. The symptoms consist of pain and a 
feeling of fullness in the nose and sinuses accompanied by severe 
headache, followed by sensations of intense burning in the throat 
and tightness and pain in the chest. Irritation of the eyes and 
lacrimation are produced. Sneezing is violent and persistent; 
the nasal secretion is greatly increased and quantities of ropy 
saliva flow from the mouth. Nausea and vomiting may also occur. 
Mental depression*of the victim is very pronounced. 
The patient should be removed from the contaminated atmosphere, 
kept away from heat, and his outer clothing should bo removed. 
Flush the nose and throat with a weak solution of sodium bicarbon- 
ate or of ordinary salt. The exposed parts should bo washed with 
soap and water. If the victim can not be removed to pure air, the 
mask must be worn between spells of actual vomiting and in spite 
of nausea and salivation. Inhalation of dilute chlorine from a 
small amount of bleach in a wide-mouth bottle is the most effective 
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therapeutic measure. Inhalation of chloroform, ether, or alcohol 
vapor is less effective. Aspirin may be given to relieve the 
headache and general discomfort. Codeine may be strongly indi- 
cated! and if necessary, should be used early. 
Screening Smokes 
From a chemical warfare viewpoint, smoke is a concentration of 
exceedingly minute solid or liquid particles suspended in the air. 
Its purpose is to obscure the vision of the enemy or to screen 
friendly troops and terrain from enemy observation. Its mission 
is thus essentially defensive and in this respect is directly op- 
posite to that of gas| for, while gas disables and kills men, 
smoke protects them by a sheltering mantle of obscurity. As with 
gas, the methodical planned use of smoke in battle was a develop- 
ment of World War I. History does record sporadic attempts to use 
smoke tactically in combat, as when, in 1700, King Charles XII of 
Sweden crossed the Dvina River in the face of the opposing Polish- 
Saxon army under the protection of a smoke screen generated by 
burning large quantities of damp straw. But the results of such 
early, isolated incidents were always too uncertain to justify the 
adoption of smoke as a recognized agency of warfare. The British 
were the first to use smoke clouds artificially generated from 
special apparatus so as to mask their gas attacks and lead the 
Germans to believe a gas attack was being put over where actually 
no gas was used. In such operations the British were able to ad- 
vance unmasked behind the harmless smoke while the Germans, fearing 
gas, were put to the disadvantage of wearing masks. Smoke was also 
used for other deceptive purposes such as to draw wasteful artillery 
fire on unoccupied sectors by generating a smoke screen to indicate 
that an attack was imminent. The Germans soon adopted these same 
tactics and in turn used them effectively. By the fall of 1917, 
the tactical use of smoko on the Western Front had become so Y/ell 
established that General Pershing cabled the War Department on 
November 3, 1917, asking that largo quantities of phosphorus bo 
quickly manufactured for filling smoke ammunition for the American 
Army, Although drop bombs filled with white phosphorus were used 
to some extent in the World War I, the tactical employment of smoke 
by airplanes was not developed to any appreciable degree. On the 
whole, the tactical use of smoke during the last war lagged behind 
the tactical use of gas. It is safe to say the possibilities of 
the planned use of smoke in battle wore only beginning to be real- 
ized at the close of the war. It is also a fact that, while the 
Germans took and held the initiative in the use of gas throughout 
World War I, the Allies excelled the Germans in the use of smoke, 
both from a qualitative and quantitative standpoint. This is ex- 
plained by the Germans as owing to the lack of phosphorus in 
Germany and its availability and employment in enormous quantities 
by the Allies. 
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The more important screening smokes are an admixture of imperfect In- 
humed oil and water vapor, white phosphorus (WP), sulfur tr ioxide- 
chlorsulfonic acid (FS). titanium tetrachloride (FM).« and HC mixture 
In general, these smokes are not toxic in the ordinary field con- 
centrations, but may be dangerous in the heavy concentrations 
formed at the immediate site of dispersion. The gas mask gives ade- 
quate protection against all of the screening smokes, FS smoke is 
more irritant and corrosive to the eyes, skin, and respiratory 
tract than is FM or HC. A form of chemical attack which presents 
great possibilities is the use of toxic smokes, DM and DA, con- 
cealed in a smoke screen. 
White phosphorus creates the densest smoke per weight of the agent, 
is a low temperature incendiary and can produce nasty burns on 
personnel. It burns in the presence of oxygen3 therefore, for 
burns with this agent immerse the affected parts in water to stop 
the burning of the phosphorus and pick out the solid particles 
from the flesh. Wet cloths may serve the purpose if immersion in 
water is not possible. Phosphorus melts at approximately 111°F| 
therefore if hot water is used, the melting particles may be re- 
moved with a cloth or sponge. 
The prompt application of approximately a 10% solution of copper 
sulphate in water will form a thin coating of copper phosphides 
on the phosphorus particles, which will stop their burning at 
once. The coated particles can then be picked out of the flesh. 
The copper sulphate solution should be applied by soaking a 
pledget of cotton, a sponge, or a piece of cloth in the solution 
and then placing it on the phosphorus. A minute or two is suffi- 
cient time for the formation of the metallic covering coat. After 
removal of the phosphorus, the burns should be dressed. All severe 
cases should be evacuated. 
Liquid titanium tetrachlorido (FM) produces acid-like burns of the 
skin and eyes. The smoke generated by the liquid FM is unpleasant 
to breathe and may cause some irritation of the nose and throat, 
but it is not dangerous. However, exposure of the eyes to spray 
will cause conjunctivitis with lacrimation and photophobia. Acid 
skin burns are produced by contact with the liquid. The eyes or 
skin should be washed freely with water and then with two percent 
sodium bicarbonate solution. 
Sulfur trioxido chlorsulfonic acid solution (FS) in liquid form 
produces acid burns of skin or mucous membranes upon contact. 
The symptoms are usually limited to an irritation of the skin, 
manifested by a biting and prickling sensation. The treatment of 
eye burns from liquid FS is most important. Irrigation with water 
should be instituted at once and continued for half an hour, fol- 
lowed by repeated flushing with 2% sodium bicarbonate solution for 
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3 to 4 hours. Upon completion of this treatment a small amount 
of 2/o aqueous mercurochrorae solution should be dropped in the eye 
to detect possible corneal ulceration. If painful, 2% butyn may 
be instilled. Cod liver oil ointment or castor oil or yellow 
oxide of mercury ointment should then be instilled and the in- 
jured area covered with a light pad. Skin burns should first be 
washed with water and then with sodium bicarbonate 
later treatment should be that of ordinary burns. 
HC Mixture produces no symptoms other than a slight suffocating 
sensation from high concentrations of the smoke. Therefore no 
treatment is needed. 
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