Chapter 4: Protection Against Toxic Agents
“Unfortunately, except for blister gases, there is no practical method of detecting gases other than the sense of smell,” wrote Brig. Gen. Alden H. Waitt early in the war.1 But sensory tests were hazardous and uncertain, particularly for chemicals with little odor or which were masked by the enemy or by field conditions, and the CWS had long sought rapid, foolproof chemical and physical tests.
By March 1942 a number of blister gas detectors, all of which were based on color changes in a dye base and had their origins in British and American developments in 1918, had been standardized. They included the M4 vapor detector kit, capable of registering even faint concentrations of nitrogen and sulphur mustards; M5 liquid vesicant detector paint; M6 liquid vesicant detector paper; and M7 vesicant detector crayon, sensitive to mustard and lewisite.2 Although the CWS had not discovered a better dye base than that developed by the British, NDRC chemists at the University of Chicago, at the University of Virginia, and at Ohio State improved its composition and developed new detector materials.3
An excellent detector kit proved to be the M9, developed with NDRC help in the CWS laboratories at Edgewood and MIT and standardized in July 1943.4 The Army considered this compact, efficient, and widely used kit one of the significant developments of the CWS defensive research program. Any soldier could learn to operate it after brief training, and it proved itself during the war in the inspection of chemical munitions at U.S. Army depots at home and abroad.
Superior to the M4 vapor detector kit in every respect, the M9 was an adsorption type of detector, consisting of a hand pump and nearly two hundred small tubes of reagent dyes in silica gel, capable of detecting even slight concentrations of such war gases as the mustards, phosgene, and cyanogen chloride.5 The discovery by Weldon G. Brown at the University of Chicago of a sensitive and specific detector for any war gas reacting to alkali (such as the mustards) was of signal importance in the development of the kit.6 Tests devised later for lewisite, carbon monoxide, and hydrogen cyanide were at once incorporated in the kit.
After a requirement was established in March 1943, the laboratory at MIT also got up an agent sample collection kit, the MIT-E12, which enabled the user to get samples of airborne agents as well as agents in contaminated soil and to keep them without loss or decomposition until they could be delivered to a field laboratory. This was standardized in August 1945 as the M12 agent sampling kit and, along with a newly developed M10 chemical agent analyzer kit and the Mil smoke identification kit, was made a component of the M3 mobile laboratory unit.7
Unknown to the American Army, the Germans had discovered nerve gases, a new class of toxic compounds. The CWS first learned of the existence of these agents after the war was over. None of the reagents in detector kits, nor any other U.S. detector devices, were sufficiently rapid or reliable to warn in time of the presence of nerve gases. In liquid form these agents reacted with the detector paint in the American kit, but no substance in it could detect the agents in spray or vapor form. Had these gases been used it is likely that only the onset of clinical symptoms would have revealed their presence. Despite the accomplishments of the United States in developing sensitive methods of detection, the definite evidence in 1945 that the Germans had nerve gases reopened the whole problem of detection.
As for enemy methods of detection, the Germans had a powder containing a dye which, when sprinkled on liquid mustard, changed color. German vesicant detector cards worked in the same manner as American vesicant detector paper, but were more sensitive to some reagents, and gave a more sharply defined color. For testing the air outside fortifications, the Germans had an apparatus with six pumps, operated electrically or
Types of gas masks, April 1918. From left, American, French, early British, and German.
manually, which forced air through six tubes of reagents. A German detector kit, comparable to CWS model M9, contained tubes of reagents and a small hand pump to force air through the tubes.8
The Japanese also had detector kits, a number of which were captured during the war. One of these, tested at the CWS-MIT laboratory late in 1943, was larger and heavier than the CWS model M9, had no reagent for nitrogen mustard, gave uneven results, and allowed misleading interpretations of tests owing to the faintness of some reactions. On the other hand, a naval-type detector examined shortly thereafter, although also without a test for nitrogen mustard, compared favorably with the M9 in design, simplicity, and effectiveness of operation, and had several good points that were considered for possible inclusion in later American models.9
The Gas Mask
Gas masks were the earliest devices for protecting soldiers against toxic agents. The German Army supplied crude masks to the troops who released chlorine at Ypres, the first chemical attack of World War I.
Army photographer wearing service gas mask with M1A2 face-piece, Camp Robinson, Arkansas, January 1942.
Between 1915 and 1918 the warring nations developed a variety of masks, some completely covering the head and others covering only the face. American troops in France first wore French and British gas masks, then the American C. E. (Corrected English) mask, and finally the R.F.K. box respirator, a modification of the British mask by Ralph R. Richardson, E. L. Flory, and Waldemar Kops of the CWS. The R.F.K. gas mask consisted of a canister, a fabric facepiece with nose clip, mouthpiece, and hosetube, and a carrier for the two units.10 It provided adequate protection against the agents used on the Western Front, but was uncomfortable if worn for long periods. After the war came the 1919-model gas mask, consisting of a facepiece and hosetube of rubber, covered on one side with elastic stockinette, a canister, and a carrier assembly. The trapezoidal facepiece was fitted with circular eyepieces of laminated flat glass, deflectors to discharge air over the eyepieces to prevent fogging, an outlet valve, an angletube, and a head harness. The canister was of the radical flow type containing a filter unit for the removal of solid and liquid particles from incoming air and charcoal and soda lime absorbents for the disposal of gases. This mask was designated MI-I-I and adopted as standard in 1921. It was supplied in five sizes and with improvements remained the standard U.S. Army gas mask until 1940. After the United States entered World War II, substantial quantities of this service mask, then designated the M1A2-9A1-4, were still available in reserve stocks.11
In improving the mask during World War II the CWS sought to
Soldier wearing service gas mask with A42112 facepiece during maneuvers, Camp Polk, Louisiana, June 1942.
make it more comfortable, increase the degree of protection, and to make it lighter. One of these steps was to develop a fully molded face-blank. It eliminated the vulnerable chin seam, the angletube, separate deflectors, and multiple metal parts in the eyepiece assembly, and it also brought the lenses of the eyepiece closer to the wearer’s eyes, thereby enlarging his field of vision and reducing the dead air space in the facepiece. This molded facepiece also resulted in lower manufacturing costs by permitting mass production methods of assembly, in contrast to the hand work required in the older masks. The new service mask was heavy and not waterproof, but it was an excellent device for protecting the wearer against toxic vapors.
Because there was urgent demand for the new fully molded facepieces, the CWS provided only three sizes of molds for its manufacturers.12 These molds were based on fitting tests on a limited number of workers at Edgewood Arsenal. Variation in the manufacturers’ molds made it possible to fit 90 percent of the troops with the so-called universal size, and large and small sizes were provided for special cases. Their wearability was confirmed in tests on more than a thousand soldiers at Camp Edwards, Mass. Difficulties in tooling for the production of these facepieces precluded further changes.
The chief gas mask problem, the CWS felt, was not the faceblank but better absorbents and filters for the canister. The possibility of meeting with new Axis toxic agents and the development of war gases by the United
States made it desirable to find better canister materials. The first attack on the problem was on the absorbents, and NDRC contracts were set up for fundamental studies at the University of Illinois, at Johns Hopkins University, and at Northwestern University.13
Whetlerite, a copper impregnated, activated charcoal, was the absorbent then used in the M9A1 canister.14 Mixed with 20 percent soda lime, this filling removed such standard gases as chloropicrin, phosgene, mustard, and lewisite. It furnished only a fair degree of protection against hydrogen cyanide and cyanogen chloride, a degree thought particularly dangerous in the case of hydrogen cyanide because glass grenades containing this agent had been found among captured Japanese munitions. Initial studies at Northwestern University confirmed the British finding that the addition of silver to the charcoal in the canister greatly improved protection against phosgene and hydrogen cyanide, and the CWS adopted this new composite whetlerite early in 1942.15 Studies later that year indicated that soda lime, included in the canister since World War I to assist in the adsorption of volatile acid gases such as phosgene and hydrogen cyanide, was no longer needed and it was removed.16
The NDRC meanwhile tackled the problem of increasing the cyanogen chloride absorbing power of canisters to meet the possibility that the CWS might adopt this substance as an agent. Research at Northwestern University led to the addition of chromium to the silver and copper already in the charcoal, a measure which considerably improved the cyanogen chloride protection of the canister, even under the severest semitropical weather conditions that could be simulated in the laboratory. The service adopted this third type of charcoal (Type ASC) in July 1943 and incorporated it in the M9A2 canister.17 Shortly thereafter, scientists developed highly satisfactory wood and coal charcoals as substitutes for the unobtainable coconut charcoal used before the war.18 As a result, the charcoal and its impregnites in the 1943-44 canister gave the United States an absorbent considered better than those in either the German or Japanese canisters.
The second phase of canister improvement involved filters, incorporated to remove solid toxic particles breathed into the gas mask canister.19 The filter paper in all canisters in 1940 consisted of a cellulose fiber mat known as alpha web, which had recently been improved by impregnating it with fine carbon particles. This filter assured substantial protection against toxic smokes, such as adamsite, but it increased the resistance to air flow and it offered only limited protection against liquid particles. The development of new mechanical smoke generators necessitated further work on the filter, because fine oil particles of the smoke deteriorated the impregnated paper. Gas mask experts tested rock wool, fiber glass, and other materials as paper substitutes, and finally found that asbestos, a material in British, German, Japanese, and Russian filters, added to the alpha web made the canister safe against minute droplets of oil.20
The CWS-MIT Development Laboratory, in cooperation with industrial paper companies and Arthur D. Little, Inc., produced three types of asbestos bearing paper, each of increasing effectiveness. After 1942 they were used successively in place of the carbon-impregnated filter paper in the M9A2 and M10A1 canisters.21 Further research led to the substitution for the asbestos of a paper fiber made from esparto grass, obtained from Morocco. The new firer had less air resistance in the canister while it maintained a filtering -Tacit), comparable to asbestos. The service further improved this filter material by treating it with dimethyl silicane, which rendered the paper highly water repellent—a useful property when troops had to ford streams while carrying the gas mask.
The M2 type service mask previously described was, from the point of view of the technical staff of CWS, an excellent product. Anticipating that gas would be used in the war, the service had designed a mask that would provide troops with the most complete protection possible against gas attack. The mask was rugged and efficient, but it was heavy (weighing almost five pounds with its steel box canister), bulky, inconvenient, and therefore unsuited to the combat requirements of World War II. Troops in training in 1940 and 1941 wore the mask unwillingly and only for gas exercises, leaving it behind on combat maneuvers. When the War
Department insisted that the mask be worn in all exercises, the ground arms reacted at once. The design had to be changed if troops were to fight effectively while wearing it.22
The requirement established in January 1942 for a lighter and less cumbersome mask for combat troops resulted in the development of the lightweight service gas mask. With a smaller, rounded canister, a shorter hose and a simpler carrier, this mask weighed 3½ pounds, yet because of better absorbents and new filter materials, it provided almost the same, though not as prolonged, protection as the heavyweight service mask.23 One shortcoming of the new mask was the increased breathing resistance, caused principally by the smaller canister. Nevertheless, when Cavalry, Infantry, and Armored Force Boards, as well as Airborne Command tests of the new mask were completed, the Army Ground Forces recommended that the mask be issued as quickly as possible.
The mobility of modern warfare, its jungle operations, and particularly the increase in amphibious operations brought demands from the theater commanders and the Army Ground Forces for an even lighter and more compact gas mask, and especially for one that could be waterproofed. The requirement suggested a snout type mask such as was used by German assault troops. This type would not have an awkward hosetube, would weigh less than two and a half pounds, be waterproof or carried in a waterproof carrier, offer the same protection as the lightweight service mask, and not interfere with the soldier’s firing in a prone position.24
The problem was turned over to the CWS-MIT Development Laboratory. In a series of tests of experimental models by the 544th Engineers of the 4th Amphibian Brigade in combat exercises at Camp Edwards, it appeared that a cheek-mounted canister gas mask of the type used by the British, rather than a snout type, would provide the least interference with combat activities. Technicians therefore modified the lightweight service mask faceblank by boring a hole in the left cavity and fitting the canister rigidly to the cheek of the blank. A new aluminum M11 canister, adapted from the German design and two-thirds lighter than the previous steel canister, had a water-repellent smoke filter and a wide, deep bed of charcoal. It was much lighter, yet it provided almost as much protection as the lightweight service mask canister. Finally, they made a waterproof
Service gas mask with M4 facepiece worn by women in training at Camp Breckinridge, Kentucky.
carrier for the mask from butyl rubber-coated cotton duck. Its multiple folding closure made the entire contents of the carrier watertight. It was later reported that in mishaps during amphibious operations, the buoyancy provided by this carrier saved the lives of a number of soldiers.25 The assembled units, weighing three pounds, were standardized as the M5-117 combat gas mask in July 1944, after production had already started.26 Over half a million of the combat masks were produced, and this was the mask which was issued to certain assault elements for the invasion of Normandy and which was carried ashore in later amphibious operations.
Among a number of special masks developed before the war was the optical gas mask, standardized in 1939. This mask, originally requested by the Navy and later by AGF for Signal, Coast Artillery, and Antiaircraft personnel using aircraft warning and fire control instruments, contained
small, optically ground lenses for instrument observation and a diaphragm for speech transmission. The poor fit and bulkiness of this mask led to a lighter model designed at the CWS-MIT Laboratory for use by the Coast Artillery and standardized in January 1944. The Chemical Warfare Board found the mask satisfactory, but the Armored Board in a later test did not consider it wholly acceptable and further development was abandoned. As the AGF reported in August 1945, “no existing gas mask is entirely satisfactory for use by armed personnel who are required to employ optical instruments in the performance of their assigned duties.”27
The diaphragm gas mask was a special mask first designed for the Armored Force and produced in January 1941.28 By means of a thin vibrating diaphragm element in the facepiece of this mask, somewhat better speech transmission was possible than in the service mask. Yet this mask had certain deficiencies. At a conference on 23 March 1943 the facts were brought out that the mask was unnecessarily burdensome, that it might make the wearer an easier object of sniper fire, that its voice transmission qualities were only slightly better than the standard service mask, and, above all, that it seemed impossible to turn out a diaphragm with an assurance that it would remain gas tight.29 After a review of this mask by using arms and services in June 1943, when the critical components, complex manufacture, and slight acoustical properties of the mask were pointed out, the Signal Corps, Army Air Forces, Armored Force, Cavalry, and Infantry rejected it. The CWS stopped production and apportioned existing stocks among the Field Artillery, Coast Artillery, and Antiaircraft Artillery, who still wanted a diaphragm mask.30 When in 1945 requests continued for a better speech mask, the CWS developed a new lightweight diaphragm gas mask, having improved acoustical properties. It was intended to replace earlier diaphragm masks carried by tank crews and by radio and telegraph operators. The war ended before it could be put into production.
Another special mask, first requested in 1940 and again by the Chief Surgeon, ETO, in 1944 was the headwound mask, for soldiers in field hospitals with head, face, jaw, or neck injuries.31 It consisted of a vinylite hood
Walt Disney with staff members of Chemical Warfare Service, January 1942, meeting to discuss a Mickey Mouse gas mask for children. From left: Col. George J B. Fisher, Col. Maurice E. Barker, Walt Disney, General Porter, and General English. Note picture of mask, left background.
with a wide, transparent vinylite eyepiece, an M11 canister, and a vinylite carrier. Although the CWS did not solve completely the problem of obtaining a gas tight seal for patients with neck wounds, it nevertheless standardized the mask at the request of the SGO in August 1944 and supplied them to the theaters.32 Continuing work resulted in a much better neck seal on this mask, but since the danger of gas warfare receded the improved model was destined only for limited procurement.33
The CWS first planned a civilian gas mask in 1937. By 1940 the service had decided that the design of the Zapon-type mask, as it was called, was not satisfactory, and had replaced it by another of rubberized fabric.34 At the request of the Office of Civilian Defense, the service redesigned this gas mask with its snout-type canister in five sizes for civilian use and obtained permission to produce it with laminated and, later, sheet rubber
facepieces, to eliminate the uncomfortable chin seam of the fabric model.35 With the growing shortage of rubber, the CWS-MIT Laboratory worked out a process for manufacturing faceblanks from impregnated felt. The CWS produced large numbers of this type of civilian gas mask under experimental contract before closing the program. Other civilian masks included the Mickey Mouse mask for children, designed by Walt Disney, and the infant protector, a pliofilm respirator for children too young to be fitted with a mask.
On the basis of World War I experience, the CWS had devised gas masks for horses and mules, as well as leggings, capes, eyeshields (since the horse gas mask did not cover the eyes), and other protective equipment. The mask was in the process of standardization early in 1943 when the mechanization-minded AGF canceled all requirements for horse protective equipment. Late in 1944, as the 10th Mountain Division prepared to go overseas with its complement of horses and mules, AGF reversed the order.36 Subsequently, the service standardized capes and eyeshields for the Mountain Division animal trains. It also designed masks for the dogs used on security patrols and for messenger work overseas, and a baglike mask to protect Signal Corps pigeons.37
Estimates of the relative value of American, Japanese, and German gas masks varied somewhat with the specimen and the examiner, but on the whole scientists felt that the U.S. masks, despite their weight, discomfort, poor vision, and other disadvantages, were “probably the best worn by any army.”38 The Japanese Army masks, though lighter, more compact, and well constructed, would not stand the wear and tear of American masks, and the canister gave somewhat less protection, particularly against hydrogen cyanide and cyanogen chloride.39 One model of Japanese noncombatant mask was superior in material, workmanship, and protection to the American counterpart, but other models were inferior.40 The Japanese had specialized masks, including a Navy diaphragm and a horse mask.
In the opinion of Generalleutnant Herman Ochsner the American mask “was highly effective in protection against gas and in that respect would meet even the highest demands.”41 But it was too heavy for the German Army, which favored a compact model with a drumlike canister fastened directly to the mask. The early German canister gave lower protection than the American, although it was improved later in the war.42 The Germans had gas masks for noncombatants, headwound casualties, horses, dogs, and pigeons.
Collective Protectors
The collective protector was a machine designed to draw contaminated air from outside a gasproofed shelter and purify it for circulation within. The collective protectors available at the start of the war were the M1A1, a 1,210-pound unit for use in large permanent installations such as seacoast forts, headquarters, and field hospitals, and the M2A1, a 615-pound unit, for temporary field tent installations.43 In 1942 the CWS-MIT Development Laboratory provided the M3 field collective protector, a small 10-man unit for installation in Ordnance machine shop trucks, office trailers, mobile surgical units, and CWS mobile laboratories. The chief difficulty lay in obtaining an air-tight seal in these vehicles. The CWS Development Laboratory at last devised a special canister with an Electrolux dust-precipitator air blower which supplied purified air through corrugated rubber hoses to facepieces worn by the tank occupants.44 The Armored Medical Research Laboratory approved the device after tests in 1944 at the Ordnance Desert Proving Ground, Calif., but then reversed its decision on the basis of later tests at Camp Polk, La., when it found no physiological or operational advantages, under high humid conditions, over the individual combat mask. Edgewood Arsenal produced more than 1,100 M1A1’s and 2,500 M3’s during the war.45
At the request of the Office of Civilian Defense late in 1941, the CWS-MIT Development Laboratory devised a collective protector for civilian air raid shelters. Under power operation it would protect adequately 40 to 50 persons; when hand-operated, 20 to 25 people. The service constructed a
number of experimental models of the lightweight machine before the requirement was rescinded.46
The Germans developed a number of collective protectors for civilian gasproof shelters, armored vehicles, and small fortifications. The pumps used to draw outside air through the canister were generally centrifugal air blowers operated by electricity, with a crank for turning the fan by hand if the electricity failed. An unusual model had a double-action bellows with a long handle that could be pumped up and down to draw air through the protector.
Japanese collective protectors were similar to those used by European nations and the United States. An ingenious model capable of purifying air for forty persons derived the power for pumping the bellows from a geared bicycle mechanism.47
Eyeshields, Dust Respirators, and Individual Protective Covers
The British, naturally more apprehensive than the United States about gas warfare, supplied their troops from the beginning with such items as eyeshields, protective capes (covers, in American military terminology), helmet hoods, light oilskin jackets, overboots, oilskin trousers, oilskin valises for antigas equipment, gasproof sacks for vehicles, oilskin stretcher covers, and antigas-pathway paper rolls. Even though the CWS procured many of these items for the British on lend-lease, the CWS itself later adopted only the first two items.
When this list of British equipment was submitted to the U.S. arms and services in an effort to establish their requirements, representatives of the Navy, Armored Force, Quartermaster, Field Artillery, and Engineers expressed an interest in almost every item, the Infantry and Medical Corps indicated interest in several items only, and the Signal and Ordnance wanted almost none.48
Believing that the enemy would attack with low-flying aircraft spraying vesicant agents, the CWS urged adoption of the eyeshield, so that troops on the march and in the field would have special protection against this hazard. After rejection of this item in the summer of 1942 by the Desert Warfare Board, which felt that its dust goggles offered equal or superior protection, AGF repeatedly turned down the eyeshield. When the
CWS suggested that other arms would need it, the AGF insisted that either goggles, the protective cover, or the soldier’s helmet brim offered adequate eye protection against spray attack.49 Finally, after General Eisenhower asked for eyeshields for his North African theater forces, “regardless of any objection to them,” the CWS procured and issued them.50
The first eyeshields that went overseas consisted of simple cellulose acetate eyepieces bent to fit tightly over the temples, rimmed with a felt strip, and held in place by an elastic head strap. Toward the end of the war the service designed an eyeshield which could be folded and carried in the pocket. This item was made in both clear and green-tinted acetate, the green for protection against snow glare and sunlight, and it could be worn over spectacles. Two small ventilation holes in the upper corners of the eyepiece reduced the fogging experienced with the first model.51 Because of the cheapness and excellent design of the eyeshield, the AGF later recommended that it replace the expensive sunglasses and dust goggles being issued. It proved to be one of the most useful of troop items. Eyeshields were intended originally to ward off drops of liquid mustard or other vesicant agents, but they would have been of signal importance if the German Army had suddenly uncovered its nerve gases, one drop of which in the eye could be lethal.
German antigas eyeshields came in a pouch containing two colorless and two yellow-green eyeshields. In designing the shields the German Army kept in mind the fact that they could protect the soldier’s eyes against intense sunshine and snow glare as well as against chemicals. The Germans manufactured only a limited quantity of eyeshields and, as far as known, never issued them.52
A nongas warfare item turned over to CWS for design and procurement was the M1 dust respirator, first requested in 1940 by the Armored Force, and soon after by the Infantry, for protecting troops against coarse, wind-driven particles. Initially, it consisted of a relatively large rubber face-blank with a felt filtering medium stitched to the blank. Later the service reduced the bulk and weight of this respirator by using lightweight felt on a wire and rubber frame, with rubber outlet valve and headband.53
Near the end of the war, technicians designed a simple, expendable respirator that the Cavalry Board found to be more durable and more comfortable and to give greater protection than earlier models.54
The Army first issued individual protective covers to theater troops late in 1942. Developed at the request of the Air Forces for the protection of air base personnel against vesicant spray from aircraft, the cover became a Quartermaster item of general issue. It consisted of a specially treated, large, cellophane bag folded into a small 4 by 7½-inch packet. A tear-tape device enabled a soldier with rifle or carbine to open the cover and don it sack-fashion in ten to twelve seconds. This cover, though it protected the soldier, enveloped and virtually immobilized him; it was an emergency measure and no substitute for protective clothing.55
German troops had no protection similar to American and British covers and capes, but relied on a gasplane or antigas sheet made of treated crepe paper, parchment paper, wax paper, rubberized fabric or plastic coated fabric, about four feet by seven feet in size. Troops could have used these sheets to cover supplies or weapons, and could convert them into protective capes by cutting a hole in the center.56
The Japanese Army had protective capes and sheets. The cape, four and one half by eight feet in size, came with a triangular-shaped hood which the soldier could slip over his head, while the rest of the cape could be wrapped around his body. The cape was constructed from brown, lightweight paper, and, not sturdy enough to withstand decontamination, would have to be thrown away after use. The sheet, made of rubberized fabric eight feet square, was intended as a cover for the soldier or equipment during an attack.57
Protective Clothing and Impregnites
The two-layer cotton permeable suit of World War I, its outer layer impregnated with 45 percent rosin and 55 percent rosin oil, reportedly gave almost complete protection against mustard vapor for forty minutes.58 The demonstrable superiority of the permeable protective suit of World War II, an impregnated herringbone-twill outfit offering effective protection
against both mustard vapor and fine mustard spray, derived in part from improvements in design. The CWS attacked basic design problems in cooperation with the NDRC, the Navy, and the Quartermaster Corps, which procured, stored, and issued the clothing. The high standards of design set by the service seemed all but unattainable. Even as the war ended, work was still in progress to eliminate the small degree of leakage past the closures and seals of the jacket and shorts. However slight, such leakage might produce serious blister injuries, since the areas of the body most vulnerable to the effects of mustard were the scrotal and neck regions.59
The superiority of World War II protective clothing over world War I type resulted mainly from an impregnite, a chloroamide designated CC-2. The search in World War I and after for a chemical that would react rapidly with mustard, and which was sufficiently stable on fabric to ensure reasonably good storage qualities, led to the discovery of CC-2 in 1924 and its intermittent manufacture on a pilot plant scale at Edgewood Arsenal.60 In 1928 the CWS accepted CC-2 as a standard impregnite. The formula for CC-2 was one of the most closely guarded secrets of the Chemical Warfare Service. Under Navy and NDRC auspices, between 1940 and 1945, scores of new compounds were tested in search of possibly better impregnites, but none proved superior to CC-2.
In contrast to the Americans, the Germans did not issue impregnated clothing. They carried on experimental work, but a shortage of materials kept them from getting very far. The few articles that they impregnated experimentally were stiff, smelly, and caused dermatitis.61
Protective Ointments
World War I efforts to devise an ointment that would prevent mustard lesions were unsuccessful, and the attempts in the years between the wars were equally discouraging.62 In the light of American knowledge in 1940, sag paste (salve antigas), as the ointment of 191,8 was called, was “even worse than useless,” though its issue to troops may have been “useful
psychologically.”63 In 1940 the CWS renewed the search first in its own and in Navy laboratories and then with the help of the Committee on the Treatment of Gas Casualties (CTGC), the Committee on Medical Research (CMR), and the National Defense Research Committee (NDRC). The aim was to find something that would penetrate the skin as fast or faster than mustard and neutralize the mustard and its decomposition products before destruction of the cells and tissues. This objective was based on the World War I theory that mustard penetrated the cells and released hydrochloric acid which then killed the cells and caused blisters.
Despite World War II efforts scientists still were unable to determine the precise mechanism of mustard action, although they suggested a promising theory that the primary action might be on essential cellular enzymes rather than on the cell as a whole.64 What seemed necessary to combat the action, therefore, was still believed to be a quick-penetrating neutralizer. Scientists speculated that this substance had to be a chlorine compound since chlorine alone seemed to destroy mustard effectively with the least injury to the skin.
In 1940 researchers began a series of tests with two promising ointments, azochloramid with triacetin as its vehicle, and dichloroamine-T, also in triacetin. The latter, produced by the Monsanto Chemical Co., appeared to be the less irritating of the two and to possess some effectiveness, but it was never entirely satisfactory owing to difficulties in obtaining quantities of the basic ingredient in a sufficiently pure form. The service issued large quantities of protective ointments containing variants of the dichloroamine-T formula and successively designated M1, M2, M3, and M4.65 These ointments were the best available at the time and under temperate climatic conditions were satisfactory decontaminants. Later tests revealed that under hot weather conditions they might be excessively irritating to the skin.66
In the summer of 1941, meanwhile, Navy chemists in the laboratories at Edgewood and in their own research laboratories at Bethesda, Md.,
devised a series of chlorine compounds, one of which, S-330, was highly effective against mustard and could be better tolerated on the skin.67 The Army adopted an ointment, M5, containing S-330 as its base in December 1943. The following year the service issued the M5 protective ointment kit, containing four 3/4-ounce tubes of M5 ointment and one 3-gram tube of BAL eye ointment, to troops in the field.68
Good as it was, M5 ointment acted primarily to destroy vesicant liquid on the skin; it could not to any significant degree neutralize mustard that had penetrated the skin. The soldier had to apply it within two to five minutes. After that the blister agent penetrated the skin and its action was irreversible. Nevertheless, it was a highly serviceable ointment.69
The Japanese Army issued individual decontamination kits to its troops for destroying vesicant agents on the skin. The kit contained powder that formed a paste with water, and absorbent cotton for swabbing the paste on the mustard area. The paste could not be applied as quickly as ointment, since the soldier had to mix the ingredients before use, and this was a vital factor in the tropics where mustard had to be destroyed within a minute or two if burns were to be prevented. Furthermore, a paste had little prophylactic value in contrast to an ointment.70
The German Army issued two decontaminating agents to its troops. The first was stabilized calcium hypochlorite, in tablet form, referred to as Losantin. These tablets had to be made into a paste with water, applied to the skin for a few minutes, and then washed off. The second decontaminant was a thickened ointment of chloroamine-T, which was swabbed on, allowed to stand, and finally washed off. Neither the Japanese nor the German personal decontaminants approached the American M5 ointment in efficiency and all-around usefulness.71
Medical Kits and Supplies
Prior to 1942 the only first-aid kit for gas casualties was one prepared in 1933 by the CWS’s Medical Division for use in chemical plants at Edge-
wood Arsenal. Although the service revised and tested the kit in 1938 as a possible military item, there appeared to be no military requirement for it and the work was stopped.72 Thus as war approached the CWS did not have a chemical warfare medical kit, nor did the Medical Department supply catalog of 1939 contain more than one or two of the drugs and preparations that had been reported by the Edgewood laboratories up to that time as effective remedies for gas casualties.
The service drew up a list of equipment and materials that should be included in regimental medical-detachment supply. The list was approved by The Surgeon General and the Medical Department Board, whose responsibility it was to standardize such equipment. They recommended that the drugs and impervious gloves and aprons in the list be packed in a Medical Department chest for issue to each regimental medical section, while the more bulky equipment such as the permeable protective clothing for medical personnel handling gas casualties, the headwound masks, and the field collective protector be held in rear area depots until required.73 In March 1942 the service standardized the first gas casualty chest, containing drugs, gloves, and aprons. The chest was modified in December 1943 as the M2 gas casualty set, and in May 1944 it was completely revised when its unwieldy trunk-type construction, weighing almost 300 pounds, was scaled down to a 45-pound Alpine pack-type set. This final gas casualty set consisted of 2 canvas pack inserts containing 6 impermeable aprons, 6 pairs of impermeable gloves, and the gas casualty treatment kit.74
The CWS procured more than 10,000 gas casualty treatment kits. The contents of the 1945 kit, representing the best efforts of wartime medical research in the treatment of chemical agent injuries, and containing in lesser or greater quantities the material also found in the first-aid kit and veterinary set, included BAL ointment (for removal of arsenicals from the skin), petrolatum and amyl salicylate (for removal of mustard from the skin), sodium sulamyd (to prevent blister gas eye infection), copper sulfate solution (to remove WP particles from the skin), copper sulfate powder (to replenish solution), sulfadiazine tablets or penicillin (to prevent secondary infection), a floating white soap (for decontamination), BAL eye ointment (for any liquid blister gas contamination of eyes), eye and
nose drops (to relieve pain of blister gases), chloroform (to relieve irritant smoke distress), amyl nitrite ampules (for hydrocyanic acid poisoning), ophthalmic discs, fluorescein, and atropine sulfate (for treatment of eye injury), calamine concentrate (for relief of mustard burn itching), forceps (to remove WP particles from the skin), a 4-ounce plastic bottle (for preparing calamine solution), and a screening water testing kit (to detect agents in water supplies).75
Shortly after the appearance of the gas casualty chest in 1942, a small gas casualty first-aid kit, evolved from the earlier plant kit, was standardized and issued on the basis of one to each twenty-five individuals and as an accessory of vehicular equipment. Its contents, based on developments reported in TM 8-285, were dichloramine-T in triacetin, hydrogen peroxide solution, copper sulfate solution, M1 eye solution, amyl nitrite, pontacaine ointment, and M4 protective ointment.76 Three years later, in 1945, this same first-aid kit contained BAL ointment, chloroform, amyl nitrite, copper sulfate, eye and nose drops, calamine lotion, and the MS protective ointment kit, the latter consisting of four tubes of MS protective ointment and one tube of BAL eye ointment.77 Over 250,000 of these kits were procured for shipment overseas.
In developing special kits and chests, the CWS’s Medical Division obtained standard medical items from the Army Medical Purchasing Office in New York, but in designing the sets, in packaging, and in stocking special items, it had to have direct contact with industrial firms. It called upon Bauer and Black, the Davis Emergency Equipment Co., Du Pont, Lambert Pharmacal, Dow Chemical, Rohm and Haas, the New England Collapsible Tube Co., Merck, Squibb, Lederle, and others. In the final procurement of the gas casualty chests, kits, and other items of issue developed at Edgewood, the Army’s medical department did the contracting. The responsibility of the CWS’s Medical Division was limited to ascertaining the military requirement and developing and standardizing special equipment and supplies.
In contrast to the American Army’s medical kits and sets, the German Army depended on individual issue of emergency items. The German soldier, for example, was told to wash the skin with soap and water immediately after contamination. A special soap, known as Mersol, was issued
for use at decontamination centers. Ten Losantin tablets for making a decontamination paste were issued to German troops, as well as an ointment of chloroamine-T in water, for the same purpose. Small, cloth covered ampules containing ammonia, chloroform, alcohol, and ether were issued to counteract the effects of the sneezing gas DM, and a suspension of chalk in copper sulfate solution was issued for WP burns.78
Protection of Food and Water Supplies Against Toxics
In 1938 the CWS began work on purification of water and continued it until early in 1945.79 Scientists devised an emergency method for purifying water for small units, employing carbon and special filter cartridges in a Lyster bag, and then chlorinating the water thus treated. However, no better method could be devised for removing agents from large bodies of water, such as found at a water supply point, than the standard procedure used by municipal water control stations (activated carbon and alum), and this was a Corps of Engineers responsibility.80
The service’s efforts to detect the presence of toxics in water were more successful. In February 1942, with assistance of an NDRC group under A. M. Buswell of the University of Illinois, the CWS began work which led to the development of a kit with which a soldier could detect contaminants. Chemists at Illinois devised specific tests for detecting the presence of sulphur and nitrogen mustards, arsenicals, selenium, and other heavy metals in water, while J. H. Yoe at the University of Virginia found a test for fluorine compounds in water.81 On the basis of this work, the Army adopted a treatment-control water-testing kit in March 1944. This kit made possible the quantitative analyses necessary to determine treatment dosages for contaminated water and to establish the effectiveness of such treatment.82 A year later the service produced a food testing kit to detect the presence of sulphur and nitrogen mustards, as well as other toxic agents, on foods and food containers.
Treatment of Gas Casualties
In 1939 the CWS was confronted with the same problems in treating, gas casualties that it had faced back in 1918. Researchers discovered no treatment for pulmonary edema caused by phosgene poisoning, for bronchopneumonia that set in following the inhalation of mustard vapors, or for lesions or ulcers of the eyes and skin caused by liquid or gaseous vesicant agents. The CWS began to attack each of these problems, later receiving assistance from the NDRC and the Committee on the Treatment of Gas Casualties.
By the close of World War II the medical research teams which engaged in basic studies on the therapy of phosgene and other chemical irritants at Northwestern, at Yale, at Chicago, and at the University of Pennsylvania had learned many things about the physiology of phosgene poisoning—principally that the mode of action was the vigorous and usually fatal injury of the lung tissue, resulting in waterlogging of the lungs. They learned little or nothing about treating it, other than that among animals surviving the flooding of the lungs, the anoxia or oxygen starvation of the tissues that resulted would respond to pure oxygen inhalation.83 The Boothby-Lovelace oxygen therapy apparatus, developed at the Mayo Clinic and the Aero Medical Research Laboratory at Wright Field, Ohio, and standardized as Medical Department equipment, was a partial answer to the problem. A subsequent development, to provide more efficient consumption of oxygen in the field, was an oxygen therapy apparatus with distributing hose, to permit simultaneous administration of oxygen to twenty patients.84 Oxygen was the one effective therapy for phosgene poisoning. Codeine might relieve the cough, morphine could be administered to quiet the patient, and when the edema subsided, antibacterial therapy (penicillin or sulfadiazine) could be administered in order to prevent pulmonary infection. Beyond this there was little that could be done.
Useful in the plants where phosgene was manufactured was the discovery that hexamethylenetetramine (HMT) was an effective prophylactic against phosgene poisoning. The compound rapidly combined with
phosgene as it entered the lungs and blocked its action on the tissue. While such a preventive had certain values in the factory and laboratory, it was of little use to the soldier who could not be continually inoculated against first one agent and then another in this manner.85
Mustard, the most important of the blister gases, is a disabling rather than a killing agent, its action painless and undetected since it is rapidly absorbed by the skin. The liquid, spray, and vapor produce severe eye injury, blisters on the body, and injury to the lining of the respiratory tract exposing it to infection. In World War I the bronchopneumonia that followed inhalation of mustard gas was responsible for most deaths from this agent.
Perhaps more work was done on the blister gases between 1940 and 1945 than in all the previous years put together. The CWS and its cooperative agencies studied the therapy necessary to prevent secondary infection, and methods of decontaminating liquid mustard absorbed through the skin.86 Before the discovery of the sulpha drugs only supportive treatment, that is, careful nursing, cleanliness, and warmth, was possible for the secondary infection, usually bronchopneumonia, following inhalation of mustard gas. Of the new drugs, sulfathiazole seemed to have the greatest protective value against the secondary infection. As the supply of penicillin increased, pneumonia cases which showed resistance to the sulpha compound could also be treated successfully. With these drugs available the secondary infection was no longer to be greatly feared.
The antimustard preparation, M5 protective ointment, while not the final answer to mustard decontamination and prevention of mustard effects on the skin, was the most satisfactory preparation devised during the war for this purpose. Researchers found no clear-cut superiority for any therapeutic agent in the treatment of mustard burns of the skin, but they concluded that the use on third degree burns of sulfadiazine ointment and petrolatum containing silver nitrate was the best treatment for the burn-like injury.87 As for contamination of the eyes by liquid mustard gas, nothing proved much more effective in preventing the rapid and
destructive penetration of mustard into the cornea than immediate irrigation of the eyes with water.
Lewisite, discovered too late for use in World War I, received its share of attention from researchers. In the winter of 1940-41, a group working under R. A. Peters at Oxford University experimented with a compound called DTH (dithioglycerol) or BAL (British antilewisite) which was quite effective in preventing arsenical poisoning by lewisite.88 Under the direction of the Committee on the Treatment of Gas Casualties, extensive studies of the new substance were undertaken in CMR and NDRC contract agencies, as well as at the Edgewood laboratories.
One of the first American results of the BAL investigation was the development by the Du Pont laboratories under CWS contract of M1 eye solution, a 5 percent solution of 2,3-dimercaptopropanol in ethylene glycol.89 Shortly after this a series of experiments indicated that a 5 percent BAL ointment was much less difficult to apply to the eyes and that, despite the pain of lewisite eye contamination, untrained personnel could probably apply effective quantities of the ointment to themselves. The service standardized BAL eye ointment in July 1943.
Hydrogen cyanide, another of the Army’s toxic agents, became the subject of a long series of toxicological and medical investigations. Hydrogen cyanide was the fastest acting nonpersistent agent known, because after a breath or two respiration could no longer be suppressed and before the man could mask he might be unconscious.
The recommended treatment for acute cyanide poisoning was the insertion of crushed ampules of amyl nitrite under the gas mask. The protective or therapeutic effect of amyl nitrite seemed to lie in its ability to form methemoglobin in the blood, converting the cyanide into relatively harmless cyanmethemoglobin. It was known that a compound called p-aminopropiophenone was highly active in forming methemoglobin, and experiments at Edgewood determined that a man could tolerate sufficiently large injections of this substance, named PAPP by the Medical Research Laboratory, to provide complete protection against the effects of the cyanides. Even more important, PAPP was almost equally effective when taken by mouth.90 This, however, was prevention and not therapy for cyanide
poisoning, just as HMT was an effective prophylactic against phosgene, and therefore suitable for protection in the laboratory but impractical in the field.
While it is true that positive and immediate militarily useful results from chemical warfare medical research were relatively meager in view of the great effort made, under the threat of gas warfare the CWS had no choice but to explore every toxic agent suspected of being of interest to the enemy and every known or conjectured aspect of gas casualty aid and treatment. To this end the full resources of medical science in this nation and in the British Commonwealth were made freely available, enabling the Chemical Warfare Service to command a degree of assistance never achieved before. The common effort was rewarded on two levels: first, there was an enormous accumulation of original scientific data, new instrumentation, and more precise methodology, the benefits of which may be estimated only in the event of gas warfare in the future; and, secondly, substantial contributions were made both to fundamental and clinical progress in medicine.91