INDUSTRIAL MERCURIALISM 
Report of an Investigation 
GENERAL INTRODUCTION 
PROPERTIES AND USES OF MERCURY 
HISTORY OF MERCURY POISONING- 
TOXICOLOGY OF MERCURY 
ENGINEERING AND CHEMICAL STUDIES 
MEDICAL STUDY 
URINARY EXCRETION OF MERCURY 
SUMMARY 
OHIO. DEPARTMENT OF HEALTH 
R J*n«TMAjRKWITH.' M.D. 
HeaJA*| 
, OMi o 
1940 FOREWORD 
The ultimate goal of the Ohio Department of 
Health is the prevention of occupational diseases by 
the control of those conditions in industry which af- 
fect the health of workers unfavorably. 
The Industrial Hygiene Program of the Ohio 
Department of Health is assigned to the Adult Hygiene 
Division and this report is presented in the hope that 
it may be of value to physicians and others responsible 
for the protection of the health of industrial workers. 
Acknowledginent of the painstaking effort in 
the conduct of this investigation and preparation of 
this report is made to the technical staff of the Adult 
Hygiene Division as follows; 
J. B. Kistler, M.D. 
W. G, Fisher, M.D. 
C, B. Young, A.B. 
C. A. Sraucker, A.B., M.S. 
A. B. Morrison, B.Ch.E., M.S. 
Signed: R. H. Markwith, M.D. 
Director of Health GENERAL INTRODUCTION 
An investigation of conditions affecting the health of employes, 
reviewed in the following paragraphs, was ■undertaken by the Ohio Depart- 
ment of Health at the request of the management of a company engaged in 
the manufacture of an electrical apparatus containing copper amalgam and 
made by a secret process. 
A communication from the company stated that employes were suf- 
fering from "sore mouths”. The communication added that the employes be- 
lieved they were suffering from mercury poisoning, while the company of- 
ficials thought the sore mouths might be due to an epidemic of Vincent’s 
Angina or trench mouth. 
Besides gingivitis, preliminary examination of sixteen of the 
employes’ group by a Health Department physician elicited the occurrence 
of many other cardinal symptoms of mercurialism, and this, in conjunction 
with the known presence of mercury in the processing operations, was 
considered justification for a tentative diagnosis of mercury poisoning. 
In order to exhaust every resource leading to the establishment of a 
definite diagnosis and a final solution of the problem, smears were made 
of the mucous membranes of the buccal cavities of all of this group. 
These smears were examined by the Ohio Health Department Laboratories 
in Columbus and found to be negative for the organisms of Vincent in 
each instance. Other organisms normally inhabiting the mouth were pres- 
ent in profusion and thus faulty technique could not have been responsi- 
ble for failure to demonstrate pathogenic organisms responsible for the 
gingivitis, (105) Mouth smears of all employes made at later dates were 
reported negative except two which were reported as suspicious. This 
proportion of suspicious findings is not unusual in an examination of any 
105 smears. 
The results of the preliminary examination of the sixteen em- 
ployes arbitrarily selected are sufficiently interesting to be summarized 
as follows: All, except one, complained of excessive flow of saliva and 
sore gums, mostly in the region of the molar teeth. Perceptible gingival 
lesions were not apparent in more than three or four instances. One 
lesion involving the tonsil was noted. Dysentery of recent occurrence 
was stated by five (two of bloody diarrhea). Constipation was stated by 
three. History of digestive disturbance was obtained in three instances. 
Fine tremors were noted in four instances. Skin eruptions having the 
appearance of itch or scabies wore manifested by throe or four. No 
psychic phenomena or erethism was observed or elicited by questioning. 
Following the preliminary examination of this group of employes 
and the establishment of a diagnosis of mercurialism affecting more or 
loss severely a considerable number of workers, plans wore formulated for 
a detailed study which would solve the problems presented by such a situ- 
ation and lead to adequate control of this dangerous exposure. PROPERTIES AND USES OF MERCURY 
This report is concerned only with mercury in its elementary 
state and combined with certain metals to form amalgams. Mercury is a 
silver-like liquid at ordinary temperatures which boils at 557,2°C. 
(675°F.) and freezes at -58.85°C. (-37.9°F,). At room temperature 25°C. 
(77°F.) the vapor pressure of mercury is 0,0018 mm. and the maximum theo- 
retical concentration of mercury vapor at this temperature is approxi- 
mately .021 mg, per liter of air. This increases rapidly with increase 
of temperature so that at 60°C. (140°F.), a temperature frequently asso- 
ciated with certain manufacturing processes, one could attain a concen- 
tration of 0,350 mg, of mercury vapor per liter of air. 
When mercury is associated with certain metals such as copper, 
silver, and gold the resulting products are known as amalgams. In this 
form, the vapor pressure of mercury is lower than that of free metallic 
mercury at the same temperature. In fact, the vapor pressure of an 
amalgam is dependent on several factors including the nature of the metal 
or metals associated with the mercury, the amount of mercury present and 
the temperature of the amalgam. It should be emphasized, however, that 
all amalgams have an appreciable vapor pressure and at elevated tempera- 
tures they may become a significant source of mercury vapor in the air. 
Other properties of mercury such as electrical characteristics, 
chemical properties and compounds are omitted here since they have no 
significant relation to the hygienic aspects of this study. 
Mercury is used extensively in a variety of ways. Some of the 
uses of metallic mercury and its compounds are included as follows; Manu- 
facture of mercury salts, instruments and thermometers, medicine, mercury 
vapor lamps, amalgams, extraction of gold and silver from their ores, 
catalysts, production of fulminate, electric rectifiers, electrical equip- 
ment, pharmacy, electrolytic chemical processes, felt manufacture, mercury 
boilers, cosmetics and petroleum refining. 
HISTORY OF MERCURY POISONING 
Many of the uses of mercury indicated in this paper are of recent 
origin. However, mercury has been known and used for many years, and its 
poisonous properties have long been recognized. It was used for industrial 
purposes in Egypt in 1600 B,C,, in Greece 400 B.C., in Romo 100 B.C., and 
in the Roman Empire 100 A,D, In 430 B.C., Hippocrates wrote a short de- 
scription of mercury poisoning in workmen. Pliny, the Younger, in writing 
of the disease of slaves mentioned mercurialism along with plurabism and the 
consumption of potters and grinders. 
Mercury was used for medicinal purposes in India 500 B-.C., in 
Persia 200 A.D., in Arabia 650 A.D., and in North Africa and Spain 8 A,D. 
About 850 A.D., mercury was used medicinally as an ointment, and in 
1170 A.D., it was used in the treatment of chronic skin diseases. In 
1495, there was an increased demand for mercury following its use in the 
treatment for syphilis (Paracelsus). 
Early in the sixteenth century, Andrea Mattily wrote a descrip- 
tion of chronic mercurialism in the workers of the Idria mercury deposits of Austria. In 1690, Ramazzini discussed industrial mercury poisoning 
and in 1761 Giovanni Scopali wrote a description of mercurial tremor in 
Idria workers. 
Quick silver has been mined in Spain since Roman times and 
Spain today ranks first in the production of mercury. For many centuries 
work in the Spanish mines was carried on by slaves and convicts. Later, 
when free labor was introduced, the hours of work were limited, due to 
the large amount of incapacitating illness among the men, A practice was 
developed in which eight days of four and one-half hours each, thirty- 
six hours in all, constituted a month’s work. 
Italy ranks second in the production of mercury. Here, a 
system of alternation of work was developed in 1897 by which the men were 
shifted periodically after one month of furnace work to two months of 
outside work and back again. The result was that the number of cases of 
mercurial!sm foil from 122 in 1896 to 5 in 1908. The United States now 
holds third place in the World*s production of quick silver, the greater 
part of the metal coming from California and Texas. The quick silver 
mines of California are not deep, a few running down about 500 feet be- 
low the outcrops. Ninety-five per cent of the output is from cinnabar, 
HgS, which carries little if any mercurial hazard in mining. Quick 
silver is also found in droplets where the men say "the silver runs 
free’'. These deposits were worked during the World War because of the 
great demand for quick silver to make mercury fulminate for percussion 
caps which is its largest use. The mouths and lips of workers after 
two weeks became swollen and inflamed and their teeth so sore that solid 
food could not be chewed. One doctor reported that the men not only be- 
came poisoned themselves, but they carried home so much mercury in their 
clothes that their wives became salivated while washing their clothes. 
The metallurgy of mercury is simple, but considerable potential 
exposure exists in the roasting process. Volatilized mercury is encoun- 
tered in furnace work, in cleaning out the condensers, and in working at 
the steam tables. 
TOXICOLOGY OF MERCURY 
lexicologically, mercury is classed as an irritant poison. It 
may be absorbed as vapor or in the form of soluble compounds of mercury. 
In the presence of certain substances, the solubility of mercury compounds 
is increased. The greater the degree of solubility the greater will be the 
rate of absorption. 
Mercury forms albuminates in reaction with cellular protoplasm 
and probably circulates in the blood stream as mercury oxychloralbuminato, 
Mercury is stored by the kidneys, liver, spleen and bones. The rate of 
excretion of mercury is influenzed by exercise, intake of calcium and hy- 
drogen ion concentration of the blood. Characteristically, the manifes- 
tations of poisoning by mercury arc noted at the point of excretion. 
Mercury is excreted by the kidneys, bowels, skin, saliva, milk, and bile. 4 
The nephritis so often encountered is believed to be directly relatable to 
excretion by the kidney, salivation to excretion by way of the salivary 
glands, and colitis to excretion by way of the largo bowel. The central 
nervous system manifestations of mercurialism are due to a diffuse en- 
cephalopathy, in the opinion of some authorities, with predominance of 
symptoms referable to the cerebral centers most affected. 
Youth, female sex, alcoholism, and infection appear to bo 
etiological factors, increasing susceptibility or lowering resistance 
to the poison. 
SYMPTOMATOLOGY OF MERCURIALISM 
The symptomatology of mercury poisoning is voluminous and may 
be arbitrarily classified as due to acute poisoning from relatively large 
doses of the poison within a short period of time and chronic poisoning 
due to smaller doses continued over a longer interval. 
For practical industrial consideration, entrance into the body 
may be limited almost entirely to inhalations of vapor and less frequently 
to inhalations of finely divided dust. Ingestion, inunction, and sub- 
cutaneous injection, although recognized as clinical sources of entrance, 
are of little significance in industry. 
The symptoms of acute mercury poisoning vary, of course, with 
the amount and rate of absorption of the poison and the mode of entrance 
into the system. Stomatitis, salivation, and discoloration of buccal 
mucous membranes, polyuria, albuminuria, anuria, diarrhea, and abdominal 
pain arc characteristic of acute poisoning. 
Chronic mercury poisoning is characterized by nervous disorders 
as evidenced by psychic disturbances or erethism and tremors, vasomotor 
disturbances, headache, digestive disturbances, insomnia, loss of weight, 
pallor, weakness, polyuria, mercury line on guns and, among females, 
disturbances of menstruation and climacteric. If the poisoning is con- 
tinued long enough, gingivitis and loosening of the teeth arc also en- 
countered in the chronic form as well as in the acute form. 
Differentiation between acute and chronic mercury poisoning is 
based on the amount and rate of absorption rather than upon any inherent 
difference in the symptomatology of the two forms of intoxication. 
Symptoms may range from the slightest to the most severe and oftentimes 
it may be impossible to draw a sharp line of demarcation between the two 
forms. 
In the investigation herein described, the complex of symptoms 
encountered were of such a degree of severity as to fall neither into 
the classification of acute nor chronic poisoning. The predominant im- 
pression inclined rather more to the acute than to the chronic, so a 
compromise "sub-acute” classification was adopted for the diagnostic 
designation of this series of cases. ENGINEERING AND CHEMICAL STUDIES 
Mercury was used in the form of a copper amalgam in the proc- 
osses studied. The amalgam was prepared by mixing copper powder and free 
mercury in the presence of dilute sulfuric acid. The amalgam was then 
dried in a steam-heated vacuum dryer. Mercury was vaporized during the 
drying period since about 10 pounds of mercury was collected in the 
attached condenser every few months. The workmen were exposed to the 
mercury vapor from the dryer only during loading and unloading periods. 
The dry amalgam, graphite, and various bonding agents were thoroughly mixed 
under pressure at a temperature of 180°F. Again mercury vapor escaped in- 
to the working room during the period of unloading the mixer. 
The amalgam-graphite mixture was pressed into cakes while hot. 
The final product was formed from the pressed cakes by sawing, grinding, 
drilling, etc,, and then baked in ovens at a temperature of 50C°F. In 
order to keep the temperature constant, the ovens wore not exhausted. 
Mercury vapor determinations were made, using the Nordlandor 
apparatus and the following results were obtained; 
Series I 
Sample No. 
Description 
MgHg/lO cu#m. 
1 
Vicinity of amalgam maker 
0.0 
2 
Vicinity of mixer (unloading) 
20. 
3 
Vicinity of grinder and south end 
of building 
12. 
4 
Vicinity of press 
12. 
5 
Vicinity of storage room 
45. 
6 
Vicinity of ovens 
85. 
7 
Vicinity of grinders (10 ft* from 
ovens) 60, 
8 
Vicinity of vacuum dryer (open) 
17. 
It was evident from the above data that the ovens were the 
largest contributing factor in creating harmful mercury vapor concen- 
trations, It was recommended that the ovens be removed from the working 
room to a small building adjacent to this department and that all of the 
grinding wheels, saws, etc., bo properly exhausted. 
Three weeks later, the above recommendations having been carried 
out in the interim, another series of samples were taken with the Nord- 
lander apparatus and the following results obtained: Series II 
Sample No* 
Description 
MgHg/lO cu.m. 
1 
Vicinity of press 
0.0 
2 
Vicinity of press 
0,0 
3 
Vicinity of press 
0.0 
4 
Vicinity of mixer (loading) 
0.0 
5 
Vicinity of ovens (not baking amalgam 
product) 
0.0 
6 
Vicinity of carborundum sawyer 
0.0 
7 
Vicinity of ovens (baking amalgam 
product) 
23.0 
8 
Vicinity of semi-automatic grinder 
0.0 
9 
Vicinity of mixer (unloading) 
3.8 
The only mercury vapor exposures found on this visit were in 
the vicinity of the ovens and near the mixer during unloading. The 
ovens, however, were removed to another building and the attendant was 
exposed to the mercury concentrations found there only a few minutes a 
day. No workmen were employed in the building to which the ovens had 
been moved. 
Four weeks later another series of mercury vapor determinations 
were made with the following results: 
Series III A (Mercury Vapor With Nordlander Apparatus) 
Sample No. 
Description 
MgHg/lO cu.m. 
1 
Vicinity of presses 
trace 
2 
Vicinity of tumbler (mixing graphite 
and bond) 
0.0 
3 
Second floor 
0.0 
Due to the dustiness of certain operations, it was thought 
advisable to determine the amount of mercury in the air present as amal- 
gam dust. Since the Nordlander apparatus was sensitive only to mercury 
vapor, the mercury dust samples were collected with the Groenburg-Smith 
impinger. Seven samples taken during this visit gave the following re- 
sults ; 
Series III B (Amalgam Dust With Impinger Equipment) 
Sample No. 
Description 
MgHg/lO cu.m. 
1 
Vicinity of press 
trace 
2 
Vicinity of press 
0.12 
3 
Vicinity of tumbler 
1.08 
4 
Four feet from tumblers 
trace 
5 
Vicinity of mixer (charging) 
270. 
6 
Five feet from mixer (charging) 
4.0 
7 
Vicinity of band saw operator 
0,13 The mercury dust concentrations were found to be very high at 
the point of emission and were much lower a few feet away. The high 
density and large particle size of the amalgam dust were undoubtedly 
the cause for this decrease. 
Three additional series of mercury vapor and amalgam dust 
determinations were made, the final determination being carried out ap- 
proximately eight months after the first investigation* The following 
results were obtained: 
Series IV A (Mercury Vapor With Nordlander Apparatus) 
Sample No. 
Description 
MgHg/lO cu.m. 
1 
Vicinity of presses 
0,0 
2 
Vicinity of mixer 
0,0 
3 
Vicinity of tumbler 
0,0 
4 
Vicinity of grinder 
0.0 
5 
Vicinity of grinder 
0,0 
6 
Vicinity of vacuum dryer 
0.0 
7 
General atmosphere 
0.0 
8 
General atmosphere 
0.0 
Series IV B (Amalgam Dust With Impinger Equipment) 
Sample No. Description MgHg/lO cu.m. 
1 
Vicinity of drilling operation (first floor) 
0,0 
2 
Vicinity of crimping operation (first floor) 
0,0 
3 
Vicinity of automatic soldering (second floor) 
0.0 
4 
Vicinity of tamping machinery (second floor) 
0,0 
5 
Vicinity of hand soldering (second floor) 
0.0 
6 
Center of room (second floor) 
0,0 
7 
Vicinity of hand soldering (second floor) 
0,0 
8 
Vicinity of crimping operation (second floor) 
0.0 
9 
Vicinity of breaking operation (first floor) 
0.0 
10 
Vicinity of crimping operation (first floor) 
0.0 
11 
Vicinity of mixer (charging) 
234. 
12 
Vicinity of mixer (four feet away while 
charging) 
3,6 
13 
Vicinity of grinder operator 
0,0 
14 
Six feet from grinder 
1.0 
15 
Vicinity of tumbler (loading) 
2.7 
16 
Five feet from tumbler (loading) 
0.27 
17 
Vicinity of tumbler (not loading) 
0,0 
18 
Five feet from tumbler (not loading) 
0.18 
19 
Vicinity of tumbler (unloading) 
0,54 
20 
Five feet from tumbler (unloading) 
0,0 
21 
Vicinity of mixer (unloading) 
28.0 
22 
Three feet from mixer (unloading) 
0.51 
23 
Vicinity of mixer (after unloading) 
0.06 
24 
Three feet from mixer (after unloading) 
0,54 
25 
Vicinity of semi-automatic grinder 
0,0 
26 
Vicinity of ovens 
0.15 
27 
Vicinity of mixer (in operation) 
0.21 
28 
Vicinity of carborundum saw 
0.0 8 
Series V A (Mercury Vapor With Nordlander Apparatus) 
Sample No. 
Description 
MgHg/lO cu.m. 
1 
Vicinity of grinders 
0.0 
2 
Middle ©f factory 
0.0 
3 
Vicinity of saw bench 
0.0 
4 
General atmosphere, north side 
0.0 
5 
Middle of room, second floor 
0.0 
6 
General atmosphere, north side 
0.0 
7 
Top of press 
2.5 
8 
Eight feet from press 
0.0 
9 
Same as No. 7 except hot plates have 
been taken away 
1.0 
Series V B (Amalgam Dust With Impinger Equipment) 
Sample No, 
Description 
MgHg/lO cu.m. 
1 
Vicinity of emery wheels 
0.07 
2 
Vicinity of emery wheels 
trace 
3 
Vicinity of presses 
0,0 
4 
Vicinity of presses 
0.0 
5 
Vicinity of band saw 
0,0 
6 
Vicinity of band saw 
0.0 
7 
Vicinity of presses 
0.0 
8 
Vicinity of presses 
0.0 
9 
General atmosphere (second floor) 
0.0 
10 
General atmosphere (second floor) 
0.0 
11 
Vicinity of tamping operation (second 
floor) 
0,0 
12 
Vicinity of tamping operation (second 
floor) 
0.0 
13 
Vicinity of presses 
0.0 
14 
Vicinity of presses 
0.0 
Series VI A (Mercury Vapor Yfith Nordlander Apparatus) 
Sample No, 
Description 
MgHg/lO cu.m. 
1 
New oven building 
0,0 
2 
New oven building 
0.0 
3 
Now oven building 
0,0 
4 
New oven building 
0,0 
5 
Vicinity of soldering operation 
(second floor) 
0.0 9 
Series VI B (Amalgam Dust With Impinger Equipment) 
Sample No, 
Description 
MgHg/lO cu.m. 
1 
Vicinity of vacuum dryer (emptying) 
trace 
2 
Vicinity of vacuum dryer 
0.36 
3 
Vicinity of lead soldering machine 
0.0 
4 
Vicinity of solder heating 
0.0 
5 
Breathing level of solderers 
0.0 
6 
Vicinity of solder heating 
0.0 
7 
General atmosphere (front of building) 
0.0 
8 
General atmosphere (front of building) 
0,0 
9 
General atmosphere (rear of building ) 
0,0 
10 
General atmosphere (rear of building ) 
0,0 
MEDICAL STUDY 
Procedure of medical studies followed in general that of the 
U.S. Public Health Service study in the hatter’s fur cutting industry. 
The medical forms (history, physical examination, and laboratory) were 
somewhat similar to those used in the classic "hatter’s fur cutting study". 
Both history taking and physical examination wore done by the same physi- 
cian. Mimeographed forms were utilized to record essential data and to 
systematize the conduct of examinations. Space was provided for name, 
sex, age, race, marital status, occupational history, past medical history, 
habits, questions for females, present history, subjective symptoms, 
physical findings, and laboratory data. Particular attention was given 
on history and physical examination to signs and symptoms which might be 
caused by or result from deleterious exposure to mercury. 
Age Groups and Length of Employment 
Thirty-four of the females (89,5 per cent) were in the age groups 
20-29 years, while 46 males (63,7 per cent) were in this same age group. 
Sixteen males (23,9 per cent) were in ago group 30-39 years. The others 
were in older or younger ago groups. 
Twenty-one females (55,3 per cent) had been employed over one 
year; 3 females (7,9 per cent) employed less than 1 year but more than 6 
months, while 14 females (36,8 per cent) wore employed less than 6 months. 
Ten of the latter 14 females (26,3 per cent) were employed less than 4 
months, when quantity production began. Fifty-throe males (79,1 per cent) 
had been employed over 1 year; 14 males (20,9 per cent) employed less than 
6 months; 11 of these latter 14 (16,4 per cent) employed less than 4 months. 
Past History 
Nothing of unusual significance was found in analysis of the 
past history. Present and Immediate Past History 
In the present and immediate past history, numerous symptoms 
were elicited, more frequently among the female workers. Mention will be 
made of the most frequent complaints. 
Gingivitis was a frequent complaint at time of examination or a 
recent occurrence according to the history obtained in 19 females (50,7 per 
cent) and 22 males (50,5 per cent). On examination, gingivitis of some 
degree was found in 9 females (23.7 per cent) and 5 males (7,5 per cent). 
This gingivitis usually took the form of injected irregular areas along 
base of gums, observed best on the buccal surface. The only two female 
employes compelled to lay off work because of symptoms showed definite, 
dusky, coppery colored, deeply injected areas along entire base of gums. 
A few exhibited small light anemic appearing areas which they stated were 
sore. A few complained of sensitivity of teeth when eating. 
Loss of weight was stated by 8 females (21 per cent) and 18 males 
(26,8 per cent). 
Ptyalism was believed to be present by 7 females (18.4 per cent) 
and 4 males (5.9 per cent). On examination, it was definitely observed to 
a slight extent only on 5 females (7.9 per cent) and 2 males (2,8 per Cent). 
Symptoms Referable to Gastro-Intestinal Tract 
Symptoms referable to gastro-intestinal tract were complained of 
by many of the employes. They will be mentioned briefly in order of fre- 
quency. 
Abdominal cramps of some degree were first in frequency and were 
complained of by 19 males (28,3 per cent) and 10 females (26,3 per cent). 
Second in frequency was constipation - 13 males (19.4 per cent) and 13 
females (34,2 per cent) according to history. Several gave a history of 
alternate constipation and diarrhea. 
Nausea, third in frequency, was complained of by 11 males (16.4 
per cent) and 8 females (21 per cent). None had actual vomiting. Diar- 
rhea, fourth in frequency, had been noted by 10 males (14,9 per cent) and 
7 females (18,4 per cent). Diarrhea with slight amount of blood had been 
noted by 7 males (10,4 per cent) and 2 females (5,2 per cent). Sixth was 
abdominal swelling, usually of slight degree, 5 males (7,4 per cent) and 
5 females (13.1 per cent) had noticed it. Loss of appetite, seventh in 
frequency, was admitted by only 2 males (2,9 per cent) and 6 females 
(15,7 per cent). 
Symptoms of Psychic Irritability 
Symptoms of psychic irritability were frequent; a greater per- 
centage of complaints being elicited among the female group. These are 
mentioned in order of frequency. Restlessness was the most common com- 
plaint - 15 females (39,4 per cent) and 11 males (16,4 per cent). Irri- tability, second in frequency, was believed to be more noticeable by 
12 females (31*5 per cent) and 11 males (16.4 per cent). Third, 13 fe- 
males (34*2 per cent) and 8 males (11*9 per cent) mentioned excitability 
as a symptom. Fourth, 14 females (36,8 per cent) and 7 males (10,4 per 
cent) stated they were somewhat discouraged at times. 
A small number of workers (14 females - 36,8 per cent), and 
7 males - 10,4 per cent) complained of bad dreams occasionally. Some com- 
plained of buzzing in the ears on occasion, A few other symptoms were 
elicited. 
Physical Examinations 
The group of 105 employes examined would be considered at least 
average in general appearance and intelligence. The chief physical find- 
ings and those of chief interest are of the nervous system. 
Fine intention tremor of fingers of a slight or moderate degree 
was noted in 32 females (84.2 per cent) and 44 males (65,7 per cent). 
Twenty-three females (60.5 per cent) and 46 males (68*7 per cent) were 
recorded as showing a fine tremor of tongue. Two females showed a tremor 
of lips and one of these a tremor of face muscles. 
Patellar reflex was noted increased in 19 females (50 per cent) 
and in 33 males (49.3 per cent). Increased bicep reflex was noted in 15 
females (39.5 per cent) and 29 males (43,5 per cent). 
Simple injection of mucous membrane of nose was noted in 12 fe- 
males (31,6 per cent) and 22 males (32,8 per cent). This may in part be 
due to inhalation of graphite dust, etc,, in the air incident to grind- 
ing, drilling and other operations. 
Gingivitis as previously mentioned and described was noted in 
9 females (23,7 per cent) and 5 males (7.5 per cent). 
Many employes had considerable dental repair, a few, false 
dentures. The company had previously insisted on dental examination and 
repair if indicated in an effort to secure good mouth conditions among em- 
ployes. The teeth, in general, were found in good condition. Pyorrhea was 
practically absent, being noted to a slight extent in about 6 people. 
Slight enlargement of the thyroid was noted in 1 female and 8 males. Over- 
activity of the gland was not considered as evident in any case, nor as a 
cause of tremor. 
Blood pressure readings taken with standard mercury sphygmoman- 
ometer generally fell within normal limits - 6 males (9 per cent) gave a 
reading of 130; while 6 males (9 per cent) and 4 females (10,5 per cent) 
gave a reading below 110. 
A few cases only of dermatitis were noted; not apparently asso- 
ciated with mercury poisoning. One case of psoriasis and two cases of 
scabies were found. A diagnosis of pulmonary tuberculosis was made on one 
female. Her physician subsequently confirmed this diagnosis by chest 
roentgenograms and physical examination. Laboratory Study 
Blood counts and clinical urine examinations were not particu- 
larly noteworthy. A slight increase in lymphocytes was noted in 20 males 
(29,9 per cent), and 11 females (28.7 per cent) had a relative lymphocy- 
tosis of over 40 per cent. Basophilic aggregation counts made according 
to the technique usually employed by the Ohio Department of Health were 
not noteworthy, being below 1 per cent in most instances. 
Albumin was found in urine of 8 females (21.1 per cent) and 9 
males (13.4 per cent). The tests for albumin were made by the sulphosali- 
cylic acid method. 
URINARY EXCRETION OF MERCURY IN EXPOSED WORKERS 
It has been indicated in the engineering study that two types of 
mercury exposures prevailed in this study. First, the exposure to mercury 
vapor originating from the heating of copper amalgam which was promptly 
removed; and second, exposure to copper amalgam dust which continued to 
prevail to some extent after the vapor exposure had been eliminated. It 
is apparent that the knowledge of urinary excretion of mercury of exposed 
workers would be of material aid to evaluate the extent of each type of 
exposure. Since it was impractical to secure representative urinary 
specimens for analysis of mercury from all exposed workers, a group of 
twenty-three employes, all working on the same shift and representing all 
the operations in the various parts of the work rooms, were chosen. 
The collection of the samples were carried out as follows; 
Sample bottles of one liter capacity previously cleaned were distributed 
to the employes chosen for the study. They were instructed to exercise 
every possible precaution to avoid the contamination of the sample with 
mercury and to return the collected urine to a designated room in the 
factory twice a day. The amount of each sample was recorded and one- 
fourth was saved for analysis. The remainder was discarded. This pro- 
cedure was continued for four days and the combined samples representing 
one-fourth of all urine excreted over a period of four days were returned 
to the Laboratory for analysis. It is apparent that the final sample 
contained one-fourth of the total output of urine for the four-day period, 
and, in reality, contained one-fourth of each voided specimen for the en- 
tire period of collection. The procedure used in the analysis of these 
samples is described as follows: Two hundred and fifty milliliters of the 
sample returned to the Laboratory was oxidized with potassium permanganate 
and sulphuric acid. Two milligrams of copper were added and the mercury 
precipitated with hydrogen sulfide. The combined sulphides were suspended 
in water and treated with chlorine gas. The excess chlorine was removed 
and the mercury was determined by titration with standard dithizone solu- 
tion in chloroform. Blank and control samples were carried through with 
each series of samples. 
Four series of determinations on the same group of employes were 
made at various intervals. The first series was started on January 29th, 
the second on March 6th, the third on May 9th, and the fourth on August 
8th, 1939. The January and March series represented four-day specimens. the May and August series were only three-day specimens. The results of 
the analyses for each individual are indicated in the following table 
and are listed in order of the decreasing concentration of mercury in 
milligrams per liter of urine as found in the first series. It will be 
noted that the table indicates the mercury findings in terms of milli- 
grams per liter of urine. They could also be expressed in terms of milli- 
grams of mercury excreted per day. Although cooperation on the part of the 
employes was generally very good, in certain cases it was suspected that 
the entire output of urine was not returned in the sample bottle. This 
would seriously affect the results of the daily output of mercury, but 
would not have such a serious bearing on the average concentration of mer- 
cury per liter over a four-day period. The following table lists the con- 
centrations of mercury found in the urine for each individual studied in 
the four series of determinations. 
Summary of Individual Urinary Mercury Excretions 
Weeks Elapsed After 
cury Vapor 
4 9 
Termination 
Exposure 
18 
of Mer~ 
31 
Employee 
Milligrams of Mercury per Liter 
of Urine 
A 
1.11* 
e—w 
wm mm 
.05* 
B 
.84 
.35 
.28 
.12 
C 
.79 
*66 
.28 
.12 
D 
.78 
.42 
.18 
.15 
E 
.77 
.51 
.45 
.15 
F 
.72 
.42 
.15 
.12 
G 
.61 
.35 
.15 
.05 
H 
.60 
.37 
.07 
.04 
I 
,59 
.26 
• 60* 
.05 
J 
.58 
.34 
.17 
.17 
K 
.56 
.42 
.22 
.13 
L 
.56 
.42 
,22 
.17 
M 
.47 
.32 
.11 
.08 
N 
.44 
.13 
.05 
.03 
0 
.44 
.51 
.22 
.07 
P 
.42 
— 
.13 
.04 
Q 
.41 
.16 
.04 
.02 
R 
.36 
.11 
.07 
.03 
S 
.36 
.31 
.10 
.01 
T 
.36 
.20 
.10 
.05 
U 
.28 
.18 
.11 
.01 
V 
.14 
.07 
.04 
.01 
W 
.12 
.11 
.05 
.01 
Average 
.53 
.33 
.17 
.07 
*Not included in averages. Time Elapsed After Termination of Exposure - Weeks 
Time Elapsed After Termination of Exposure - Weeks 
URINARY EXCRETION OF MERCURY AFTER TERMINATION OF EXPOSURE The averages of the foregoing data may also be represented in 
graphic form. The rate of mercury excretion in milligrams per liter of 
urine is plotted against the time elapsed after termination of signifi- 
cant exposure to mercury vapor in the two graphs shown herein. The 
first chart is a rectilinear graph of the data, whereas the second is a 
semi-logarithmic graph of the same data. It is noted that the rate of 
excretion approximates a straight line function of the log of the time 
elapsed. 
These graphs may also be expressed as an equation; 
(1) R = -.51 log T + .83 
R = rate of mercury excretion in milligrams 
per liter 
T = time in weeks elapsed after termination 
of exposure 
The question at once arises whether this data might not be used 
to determine mercury excretion at the time of termination of exposure 
from the rate of excretion at any particular interval. For example, if 
the rate of excretion for an individual, after his exposure has been 
terminated for 10 weeks has been determined and found to be ,30 milli- 
grams of mercury per liter of urine, by following back parallel to the 
line on the chart the rate of excretion at 4 weeks is found to be approx- 
imately 0,51 milligrams of mercury per liter of urine. The same infor- 
mation can also be obtained from the following equation: 
(2) R = -.51 log T + .83 t a 
a = difference in rate of excretion at 
specified time T 
The value of (a) may also be obtained independent of the graph 
from equation (1). In the example of ,30 milligrams of mercury for the 
period of 10 weeks the value of (a) is -,015. Then substituting in 
equation (2) the excretion of mercury 4 weeks after termination of ex- 
posure would bo - 
R = -.51 log 4 + .85 -.015 
R = .51 
In making these calculations it has been assumed that the graph 
for any individual under consideration parallels that of the group aver- 
age for this study. An examination of the summary of individual mercury 
excretions reveals that this is not strictly true. It is noted that in 
general, the slope of the curve varies somewhat with amount of mercury 
initially excreted. It is evident therefore that this equation derived 
from the average data collected from the 23 individuals selected for this 
study must be used with proper reservation when applied to any other in- 
dividual cases. The value of extrapolation on this graph is questionable, 
particularly in the regions approaching the point of termination of ex- 
posure and the time at which no more mercury will be excreted. However, 
it may give a rough approximation of these limits. SUMMARY 
1* An investigation of the facilities, materials, and proc- 
esses of an industrial establishment engaged in the manufacture of an 
electrical apparatus revealed the presence of a mercury hazard. 
2. Opportunity was afforded for the observation of employes of 
this plant during and following significant exposures to mercury in the 
form of vapor and amalgam dust. 
3. Exposure to mercury vapor over a period of one year re- 
sulted in positive signs and symptoms of mercury poisoning in the workers 
examined. 
4. Sore mouths, fine tremors of fingers and tongue, digestive 
disturbance, constipation, dysentery, skin eruptions, excessive flow of 
saliva, loss of weight, nausea and psychic irritability were the symptoms 
of mercurialism found in this study. 
5, Mercury vapor samples taken with the Nordlander apparatus 
gave concentrations up to 85 milligrams of mercury per 10 cubic meters 
of air. These concentrations are not surprising since a considerable 
quantity of the amalgam was heated to 500°F., at which temperature the 
vaporization of mercury is comparatively rapid. 
6, Amalgam dust samples taken with the Greenburg-Smith im- 
pinger after elimination of the mercury vapor exposure indicated that 
amalgam dust by reason of its greater weight settles out rapidly and 
concentrations rapidly decrease as the distance from the source of pro- 
duction increases. It is doubtful if mercury dust played a very im- 
portant role in the production of symptoms of mercurialism among the 
employes. 
7. Institution of control measures resulted in the practical 
disappearance of symptoms of mercurialism among employes observed and 
the virtual disappearance of detectable quantities of mercury fumes and 
dust from the general atmosphere of the factory. 
8. Excretion of mercury in the urine was followed for a period 
of eight months after the mercury vapor exposure was terminated. The 
amount of mercury in the urine ranged from 1,11 to 0,01 milligrams per 
liter and the rate of mercury excretion was found to be a function of the 
log of the time elapsed after the termination of the exposure. BIBLIOGRAPHY 
Alekseev, R.I.; Determination of Mercury and Silver by Means of Dithi- 
zone in the Presence of Other Metals. Zavodskaia Laboratoria, 7, 
pp. 415-17, 1938. 
Fraser, A.M.; The Determination of Mercury in Air and Urine. Jour. 
Ind, Hyg., Vol. 16, pp. 67-76, 1934. 
Fraser, A.M., Menville, K.I., and Stehle, R.R.: Mercury Laden Air; 
Toxic Concentration, Proportion Absorbed, and Urinary Excretion. Jour. 
Ind. Hyg., Vol. 16, pp, 77-91, 1934. 
Gelman and Dervig; The Problems of the Fate of Mercury Fumes and Mer- 
curial Compounds in the Organism. Jour. Ind. Hyg,, Vol, 19, p, 215, 
1937. 
Gettler, A.O., and Lehman, R.A.: A Simplified Procedure for the Deter- 
mination of Mercury in Urine. Am. J. Clin. Path., Tech. Supplement 8, 
pp, 161-64, 1938. 
Goldman, F.H.; The Determination of Mercury in Carroted Fur. U.S. 
Treasury Department, Public Health Reports, Vol. 52, pp, 221-23, 1937. 
Hamilton, A.: Industrial Toxicology. Harper and Brothers, Publishers, 
New York, pp, 72-81. 
Kober, G.M. and Hayhurst, E.R.; Industrial Health. Blakiston's Son 
and Co., Philadelphia, 1924. 
McCarrol, C.F.; Hazard of Mercury Vapor in Analytical Petroleum Labo- 
ratories. U.S. Department of Interior, Bureau of Mines, Report of In- 
vestigations 3475, Oct., 1939, 
McNally, W.; Toxicology. Industrial Medicine, Publishers, Chicago, 
pp, 199-219. 
Neal, Paul A.; Chronic Mercury Poisoning - Outline of Lecture Given Be- 
fore the Industrial Hygiene and Sanitation Seminar, Washington, 1936. 
Neal, Paul A.; Mercury poisoning from the Public Health Viewpoint. 
Am, Jour. Pub. Health, Vol, 28, pp, 907-18, 1938. 
Nordlander, Birger W.j Selenium Sulfide - A New Detector for Mercury 
Vapor. Ind. and Eng, Chem., Vol. 19, pp, 518-21, 1927. 
Winkler, W.O.: Report on (the Determination of) Mercury (in Foods), 
J, Assoc. Official Agr. Chem., Vol. 21, pp. 220-28, 1938.