CHAIRMAN
BOWDITCH: Our first speaker this afternoon, as compared with some
of those whom we heard this morning, is a relative newcomer to
industrial medicine. Following periods of private practice and
general medicine in the Army, he had his first industrial work in the
Plastics Division of the duPont Company at Arlington, New Jersey, and
is now medical director of the Electric Storage Battery Company in
Philadelphia.
Dr. Francis B.
Lanahan will speak on Preventive Medical Armor for the Lead Industry.
Preventive
Medical Armor for the Lead Industry
By Francis B.
Lanahan, M.D.
Medical Director,
Electric Storage Battery, Co., Philadelphia, Pa.
November 1948
November 1948
I should like to preface my prepared presentation by a few remarks
which I am stimulated to make in light of the tone of the discussions
which preceded the luncheon period. My relative youth and brevity of
experience in industrial medicine prompts me to make the obvious
remark, that my position here at this microphone draws heavily on the
courage of my convictions. At Philadelphia, the Electric Storage
Battery Company has two plants. We have, to our conviction,
over 2,000 people
With that preface to
describe the environment that my presence here represents, I should
like to present this for your consideration.
Purges are known
chiefly within the walls of Communistic domination. Ulcerations on
the body of nations inflicted by extended arms of the Marxian Octopus
as excised by healing Christian action. Curative or destructive are
today's searching forces.
Curative and
constructive are the aims of The Electric Storage Battery Medical
Division in Philadelphia. Preventive medical principles form the
foundation of the Division's reorganization instituted one year ago.
Assessment of all established procedures was instituted. On the body
of the Preventive Medical Program, lead control methods hung like a
withered aim, helpless to prevent illness.
Though harsh is our
criticism of established methods, sincere is our admiration for
investigators who applied these methods in the light of past
knowledge. It is believed these same investigators with their proven
abilities will, with the stronger light of present knowledge, lead
the industry forward into the arena of preventive medicine.
As our present
control methods are known to be common to the lead industry in
general, our convictions and corrective measures are presented here
for general consideration.
Entering the field
of lead toxicology, we carried deep rooted convictions concerning the
soundness of preventive medical principles and the wealth of benefit
they hold for industry. We looked for methods of control indicative
of levels of lead absorption within limits compatible with health.
Methods in use were found to be non-specific of lead absorption and
demonstrative of existing tissue damage. Invariably, the horse was
out of the barn. Nor did we know which horse to look for. When
analytical methods were resorted to, it was for specific diagnostic
purposes; indeed, too late with too little for preventive medical
aims. We found the use of hemoglobin determinations, stippled cell
counts and physical examinations established as the medical methods
of choice, and we followed them, lacking knowledge of better means.
These revealed established disorders of structure and function.
Lead in air
determinations were in use. These necessarily were brief and
infrequent when related to the individual's total work exposure. They
could not reflect negligent working habits. Hygiene instructions
fell on torpid health attitudes as on the well known duck's back.
The knowledge that these methods and working habits were widely
existent in the lead industry gave small and unwanted consolation.
To establish preventive medical principles a wide chasm appeared
before us. It was the void between lead exposure and toxic lead
absorption, between results of spot air samples and actual lead
absorption during the total work period, influenced by negligent
working habits.
It was the darkness
obscuring failing tissue defenses of the worker whose prolonged
exposure to generally safe environment could be causing insidious
damage. A bridge was needed to span the chasm and give firm footing
for the preservation of health. Nature is found to give the bridge.
An instrument of the Divine Scientist, human metabolism, spans the
chasm. The man on the job is the best impinger and precipitator of
the lead to which he is exposed. His period of collective samples
represents his total working period. His faulty working habits are
reflected. These facts are recorded in analytical studies of his
excretions.
The direct
relationship between atmospheric and oral lead contamination and lead
excretion in blood, urine and feces has been revealed by the meticulous
studies of Dr. Robert Kehoe and his
associates at the Kettering Laboratory. Ranges of excretions related
to casual and to occupational exposures and compatible with health
have been indicated by them.
Criteria for dealing
with workmen on the planes of their lead absorption and excretion
have been established by them on the basis of long experience. The
use of these analytical studies are known to all of us. Essentially,
our application of them has been for diagnostic purposes. When we
have been alarmed by anemia, high stipple count or clinical evidences
of disorders which could mean lead intoxication, we have resorted to
them.
Few of us have
applied the analytical measures as preventive controls. Known
outstanding exceptions have been the programs developed by Dr. Hamlin
in the American Brake Shoe Corp. and in the Ethyl Corp., but to a
lesser degree in certain other industries, by Dr. Kehoe. The
majority of us have placed the burden of our negligence on the
complexity of analytical procedures. We can no longer afford to
retain our present methods in the guise of lead control. We must
recognize them for their inadequacy as preventive measures and resort
to them in their true function as secondary diagnostic tools. This
change is forced upon us by the present availability of a simplified,
rapid analytical method to determine lead in urine spot samples.
This is the
procedure described by Dr. Jacob Cholak and his associates at the
Kettering Laboratory in the January, 1948 number of the Journal of
Industrial Hygiene and Toxicology. Though rapid, the method demands
studied care to avoid contamination and technical errors. Yet, it is
practical within the abilities of all of us who are determined to
strive for the highest plane of medicine and hygiene.
It is our purpose to
use this method for the regular observation of our workmen. Relying
generally on spot urine samples, we will study larger volumes or
frequent spot samples of urine in the event a single spot result
suggests an increasing range of excretion.
When high range of
excretion is indicated by the additional studies, samples of blood
and urine will be obtained for more precise analysis.
As the rapid method
is known to confuse bismuth with lead, it will be routine to inquire
of any medication being taken by the workers. The incidence of
bismuth in the routine studies is expected to be small. When high
values are obtained, the longer method of analysis will be employed,
thus excluding bismuth or any other metal than lead.
To minimize
contamination of the samples by work clothing it is planned to
collect the samples before work clothes are worn or after showers.
Collection of samples at the beginning of a shift is likely to
exclude high concentrations or dilutions of the samples. Equipment
necessary to apply the use of the rapid method is approximated to
cost $3,000. As the analyses must be made in an atmosphere free of
lead, the cost of air conditioning a room in the production area
would have to be accounted. A 500 sq. ft. area is considered
adequate for the analytical laboratory. A technician working under
the supervision of a chemist can make 30 to 40 determinations daily.
To avoid phosphate precipitation, the samples must be analyzed as
soon as possible after they are voided and always within 24 hours. A
general survey of the plant by this method will establish the mean
excretory levels of the men working in specific areas. On this basis
a schedule of interval studies can be established. Attending to
necessary precision, the ease with which the analyses can be made
will allow for a flexibility of the scheduled studies to check
variations in production methods and environmental factors.
This routine
applicable to group studies will be applied to individual workmen
whose excretory levels fail to conform to mean group values. Air
analyses will be used to accomplish its present purpose but it will
gain a firmer footing of usefulness in distinguishing the atmospheric
factor of contamination in suspected environments.
The suspicion will
have been cast by high mean values among the workmen of the
particular area. Should our facilities and the personnel permit us
to develop our own analyses by the longer methods, as has been shown
to be practical by Dr. Hamlin and Mr. Weber of the American Brake
Shoe Corp., the combined equipment is judged to cost about $10,000.
As in the general
field of industrial medicine, small plants with limited budgets can
share the benefit of this quality of medicine and hygiene by pooling
their needs and spreading their expenses through the use of centrally
located industrial clinics.
The qualification of
such existing clinics for our particular need or the stimulus to
develop them is a fertile field of activity for the Lead Industries
Association.
As we progress
toward the accomplishment of our program we do so with the
stimulating conviction that our efforts will establish a regimen of
preventive medical control which will — Keep men fit for their jobs
and jobs fit for men.
CHAIRMAN
BOWDITCH: The principal discussion of Dr. Lanahan's paper will be
by a man from whom you heard this morning. He is a specialist in
industrial medicine and toxicology of many years' standing, a member
of the Committee on Lead Poisoning of the American Public Health
Association, associate professor of medicine at Marquette University
and consultant to Globe-Union. Inc. and to a number of other
industries and insurance companies. Dr. Elston L. Belknap.
DR. ELSTON L.
BELKNAP [Globe-Union, Inc., Milwaukee, Wis.]: Mr. Bowditch,
members of the Lead Industries Association, friends and co-workers: I
believe that Dr. Lanahan is to be congratulated for his convictions
and his determination to approach this in a very basic way. I wonder,
and perhaps he can answer me shortly, whether his method of urine
examination, spot samples and group samples, will replace the
time-honored method of physical examinations for lead lines, blood
studies for hemoglobin, types of red cells, stipple cells and
history, or whether it is used to supplement it. I am interested to
know how soon, also, he thought he could recheck his workers with
this method.
For instance, if he
has 2,000 workers and 40 can be done a day, it would take about fifty
days before he could get back and re-check a worker. Perhaps he will
supplement that with the other usual forms of treatment in the
meantime. My experience with lead in the urine has been to get it,
if possible, about twice a year on a lead worker, preferably a
twenty-four hour urine that has been collected at home, away from the
plant. It is then studied by the Fairhall modification of the
chromate method, which, though it takes three or four days, we have
felt from experience has been the most fundamentally safe procedure
because it is primarily an analytical chemical method. I understand
that Dr. Fairhall has modified this so that the analysis can be done
in a matter of hours. This, I believe, will answer the objections to
this method.
It seems to me the
question comes back to this. When you have done an examination of
lead in the urine, what do you have? Do you have a diagnosis of lead
poisoning or do you have a diagnosis of lead absorption? Certainly,
the Public Health Committee, of which Dr. Kehoe is chairman,
specifically said that no one laboratory finding made the diagnosis
of lead poisoning and, as already has been brought out here by a
number of speakers, including Dr. Mayers, whom I have always admired
primarily for her ability as a clinician, that one must view the
patient as a whole. No one should attempt to make a diagnosis of
lead poisoning by any one laboratory finding. I have seen workmen who
have become ill with relatively low urine leads.
The man that I
mentioned this morning, for instance, I believe had about — 0.25
mg. of lead with no symptoms, and the day he got in the hospital, he
had 0.14 mg. of lead per litre of urine. I do not believe that that
was the result of any magical treatment that he received in that
interval. I think that is simply the variation in urine findings
that one must expect in these cases.
On the other hand, I
have seen men working for thirty years in the storage battery
industry with urine values as high as 0.5, 0.6 and 1.0 mg. of lead
per litre of urine, who have never been disabled, ill, lost any time
and have shown no anemia, who have had no wristdrop, no lead
encephalopathy.
They have normal
blood pressure and a normal routine urine. One such man is still
turning out a good day's work at the age of sixty-five, and he dates
back to the time when conditions were not as we would desire them,
when 25 years ago, 75 percent of the men had evidence of heavy lead
absorption. We know also that our lead in the air at times is much
more than it should be, 3, 10, 12, 15, 18 mg. per 10 cu. feet. Of
course, we have corrected that now with air line respirators using as
much suction at the source of the dust as possible. In modern
production methods, even when you are improving a situation, often
the worker has to use the respirator.
Of course, no one
can deny if the respirator is used continuously and no effort is made
to correct conditions of lead exposure, it is a confession of
engineering weakness. If you wish, however, to keep men from being
sick, I am afraid you are going to use respirators occasionally in
the storage battery industry while protective suction equipment is
being fitted into production. In fact, if that man I was talking
about this morning, could have a job found for him, and I think it
can be found, where he is using not an ordinary respirator which he
is likely to discard, perhaps, because he does not get enough air
through it, and is given an air-line respirator, that would be just
the same to me as if he were moved out from the lead exposure. I
have done that again and again, and the man is still making good
money and he is satisfied; the company is satisfied, because he goes
on and continues his convalescence even while working. We covered
this morning, I think, what constitutes lead poisoning or true lead
intoxication. Lead absorption is one thing; disabling lead
intoxication is another. We are not using those terms to escape any
responsibility. We are simply wanting to be precise, as we like to
be in any field of medicine.
A sign of lead
absorption, certainly, is lead line, a finding which can be easily
determined by spot illumination, even a flashlight, or better still,
a head mirror and a small hand lens which costs about ninety-five
cents, incidentally. One can then definitely say there is or there
is not a deposit of linear or round row of dots in the gum tissue
next to the teeth.
Of course, one
should know that the individual has not been taking bismuth for the
treatment of syphilis. Otherwise, the physician cannot rule out the
fact that the apparent lead line may be a bismuth line. I believe I
have seen some perfectly marvelous lead lines that excited me then I
found out when the Wasserman report came back and after a little
private conference with the individual, that he was getting bismuth
as treatment for syphilis. In fact, some of the men doing
syphilology insist that a patient is not receiving sufficient bismuth
unless he shows a bismuth line.
One does not always
see a lead line if a man has good teeth. A case that I had had
perfect teeth and showed no lead line until after he was disabled.
The pyorrhea, decay and detrius around teeth seem to be a precipitate
of what is apparently lead sulfide in the gum. However, that is
merely an evidence of lead absorption. Certainly, if there is no
bismuth to be confused with, and if one sees a lead line, one knows
that the worker has had too much lead absorption and the physician
should be on his guard regarding a possible disabling lead
intoxication. That is fully as important to me as the determination
of the lead value in the urine. It is certainly a good deal less
expensive.
In doing medical
work in industry, one has to learn to fit in with production
schedules. The men are not always anxious to come in for periodic
re-examinations even though it may be on company time, and the
company is not too anxious to have them. However, I want to see the
men as often as necessary. That may be every day in some cases,
though usually every two weeks and in some cases every month or three
months, depending on the concentration of exposure. But to make an
examination of the man for a lead line, to talk to him, really to get
that patient-doctor relationship that Dr. Johns spoke about this
morning, to take his blood pressure and to make a note and record the
facts is usually a matter of only a very few minutes.
Then, if one's
technician is working at the same time on another group of men and
gets the hemoglobin and the stippled cells, one can fit, as you see,
right into production. Nobody warms the chair very long. But we have
our information, and we see the man as often as we need to in our
best judgment. We have men who have been having their ears stuck for
blood every two weeks, for twenty years, and, if we miss them, we
hear from them. If we forget to call them in, they come in
complaining, "Why don't you call me in?" That is something
you would not expect, but those old-timers know the conditions that
were there before we started this system, and they know that it pays
to have this medical observation. So much for lead line, which is a
simple procedure and which I should like to illustrate presently.
Like a lead line, a few stippled cells, say, 5 to 10 per 50 fields,
are also an indication of lead absorption but are not likely to mean
lead intoxication. They are much simpler to study than lead in the
urine. Lead in the urine is extremely valuable in mass group studies.
It is valuable for research purposes and, certainly for medico-legal
cases for doubtful cases.
I hope I have
intimated that I have no quarrel with people who are interested in
doing lead in the urine. I think that it is a valuable and helpful
adjunct, but as Dr. Fairhall has said, urinary lead excretion is one
of six cardinal factors in the diagnosis of lead poisoning and,
standing by itself, a urinary lead indicates nothing but lead
absorption. I should like to emphasize the symptoms of lead
intoxication. As I said this morning, if a man is sick, if he is
really ill, if he is weak, if he is nauseated and vomiting, and if he
has a real constipation or occasionally if he has diarrhea, and even
more rarely, if he has a fleeting arthralgia, or joint pains, with
all the other factors, if we know that he has been exposed to lead,
if he shows evidence of lead absorption in some one of those ways,
with those symptoms, plus a rising stippled cell curve, then we know
that he probably has true lead poisoning. Then it is just and wise
to admit it to the patient promptly and tell him what he has and see
that he gets immediate relief. Fortunately, relief can be given to
the most severe type of violent lead colic in 20 to 30 minutes after
the injection of calcium gluconate.
I am especially
interested in trying to make this clear to you today because this is
what I try to make clear to my medical students and what we also try
to make clear to the doctors in our county and state medical
societies. The doctors are the harder problem, incidentally.
We make the
distinction between lead absorption and lead intoxication, because,
in a perfectly sincere manner, the average doctor who, perhaps, has
seen one or two cases of lead absorption and intoxication in his
life, if any, even in medical school, often relies primarily on the
statement of his patient, "Yes, I work with lead." "What
do you mean you work with lead?" "I work with paint."
"What kind of paint?" "I don't know. All paint has
lead, hasn't it?" Unfortunately, the doctor does not always
pursue that type of questioning until he is forced to on the witness
stand, and then it is somewhat embarrassing to him as a physician to
admit his error in being led astray by his patient.
In our State our
Industrial Commission examiners are often called on to act as
attorney for an applicant, and I have heard them go through that
questioning before a hearing comes to pass. If the applicant cannot
answer intelligently, they say, "You have no case. Go find out
what kind of paint you are working with." If the doctor has the
facts he should speak with authority but the average doctor does not
realize that he is regarded by a layman as an authority. One of our
problems is to make the average physician realize the weight that is
put upon his words. A patient often comes to him and says, "Doctor,
I have been working with lead, and I have a bellyache. Don't you
think I have lead poisoning?" The physician often replies,
"Well, I don't know; perhaps you have," and then passes it
off. He does not even think of the possibility of this going to
court. He finds a little anemia, with or without stippled cells: he
may not even look for lead line and probably forgets to have a urine
lead. Then suddenly he finds himself called up to a court hearing
and he has to make good the mistaken idea the patient had, that his
physician thought he had lead poisoning. Such a physician is in for a
bad half-hour on the stand, with a competent cross-examination by an
experienced attorney.
The physician, if he
wishes to speak with authority, must make his diagnosis one that will
stand up not only in court but that he could get up and argue for
before his county medical society. There is the jury of his true
peers, and every word he says to them has to stand the severest kind
of scrutiny.
Even though he knows
that he cannot make a diagnosis on one laboratory finding alone, he
must depend on exposure, plus the following facts: There must be
evidence of lead absorption shown in the urine and gums or a few
stippled cells. There must be actual signs of intoxication, usually
a disabling colic and usually terrific constipation, obstipation, we
call it, which does not respond to any cathartic. That makes up the
ordinary kind of lead intoxication. Ninety per cent of the cases are
lead colic. Hunter, of England, has said that there are ten times as
many lead colic cases as lead palsy cases. Most of us see very few
lead palsy cases, fortunately. I have seen, perhaps, half a dozen in
twenty-five years.
When we have looked
at this thing from the point of view of industrial exposure, then we
have to go at it from the standpoint of differential diagnosis.
Does this man have a
gallbladder colic? Does he even have a coronary occlusion referred
pain to the abdomen? Does he have a pancreatitis? Does he have kidney
colic? And, in the case of a palsy case, are we dealing with,
perhaps, an alcoholic, or infectious neuritis? It is a helpful sign
that with most cases of lead palsy, there is no pain, and the palsy
is primarily extensor rather than flexor.
I have gone into
some detail on this because the usual physician has not had
experience with this type of industrial exposure. By and large, by
his own admission, the average doctor knows very little about it
except what he reads in the textbooks. These, in many cases, are
perhaps twenty years behind the times.
The problem, then is
one of education of our young physicians as well as education of the
laymen, of management and of the worker to distinguish the points I
have been making.
In regard to
residuals, in my experience, the 90 percent of the cases which go to
make up lead colic come through without any permanent residual.
True, they may have temporary anemia. The lead palsy cases may have
a residual, but not always, if treated properly.
Lead
encephalopathies, the third and rarest of the three types of lead
intoxication, may have a serious residual, if they recover at all,
such as mental
involvement, but, again, they may come through, as did some of the
ethyl-fluid cases, without any residuals at all. I would not like to
leave anybody with the impression that we do not meet lead poisoning
anymore in modern industry. I agree with Dr. Johnstone, that in the
small industry we are likely to have it all the time. It frequently
appears in unusual places in many small plants.
The accompanying
photographs show how we go in what we think is a 1, 2, 3 manner.
[caption] Fig.
1--The old and new method of inserting separators between storage
battery plates.
Fig. 1 — I show
this photograph of inserting separators between storage battery
plates because I think any layman who has never done anything with
lead — and the average doctor has to be regarded as a layman in
this area — can tell, by looking at the left-hand picture, that
conditions in that picture are not nearly as good as they are in the
right-hand picture. You can see in the picture on the left-hand side
that a plank has been thrown on the floor; lead dust can fall on the
plank and be kicked up and inhaled. In the right-hand picture there
is a slotted rack so the dust falls through to the floor where it
will not be kicked up as dust and then can be washed down at the end
of the working day. In the right-hand picture again we have slotted
down-draft suction tables. I think you can see for yourself that
that man on the right has a much safer job. In spite of that, we
insist that they wear respirators, whenever possible, though,
practically, the engineering precautions there have cut the lead
exposure remarkably.
[caption] Fig.
2--The definite, punctate deposit of lead sulphide appearing as small
black dots, in the mucous membrane next to the teeth.
Fig. 2 — Often we
have the problem as to diagnosis of a lead line. "Doctor, have
you ever seen one?" Some doctors admit that they have not, but I
think this picture proves that there is such a thing. You see here
the definite, punctate deposit of lead sulphide in the mucous
membrane next to the teeth. The dirt and detritus stippled cells
which is quite enough often to be associated with disabling lead
colic.
Figs. 4 and 5 —
This periodic re-examination chart gives you an idea of the value of
recheck studies. These examinations are made about every two weeks
with the date at the top; then at the side the particular symptoms
that we are looking for, either weakness, headache, drowsiness, if
there was a brain involvement and the usual gastrointestinal
symptoms, such as constipation or colic.
We do watch the
weight though the weight does not give any specific information, only
to indicate something as to the general physical condition of the
man. Then we test each man for extensor weakness of the wrist at the
same time we are taking his blood pressure and looking at his teeth.
Teleky, I think, was the one who brought out most clearly the
importance of testing the extensors prophylactically. We make a note
as to the pallor, the number of teeth opposite which there is a gum
lead line, and the strength of the wrist extension. We observe the
blood pressure finding also because we are interested in finding
whether these cases are going to go on and develop an increased
amount of hypertension and arteriosclerosis as some have alleged in
the older literature. To date we have not seen that in our
experience.
At the bottom of the
chart we have a place to record stippled cell count and the
hemoglobin. In one particular case, early in the.
[caption] Fig. 3 —
Photomicrograph showing stippled blood cells.
[Missing Page 51-52,
probably mostly figures, with a small amount of text leading up to
page 53 here:]
and the hemoglobin.
In one particular case, early in the game, when we did not take
warning quick enough, he was running 10, 21, 30, 110, 217 stippled
cells and we still let him stay on the same job. He began with
diarrhea, which was an intestinal influenza, and at first he had no
lead line. Then he suddenly blew up with constipation and afterwards
he had his lead line.
The anemia was a
late development here. That is the most important thing. I think,
in the blood picture regarding lead. We all agree that lead
stippling, or stippling of red cells is not a specific indicator for
lead absorption or intoxication. You may find it with Hodgkin's
disease. Benzol poisoning, tumor, malignancy, any type of severe
anemia, will eventually show nucleated red and stippled cells, but
with the lead intoxication, you get your stippled cell rise early,
long before the hemoglobin drops.
In this case he did
not have his drop to 65 and 60 hemoglobin until after he was
disabled. If we had been relying on the hemoglobin, we would have
allowed him to go a lot further than we did, absorbing even greater
amounts of of lead.
Following calcium
gluconate intravenously, the patient went back to work and worked for
two or three years. He was in excellent physical condition before he
left our employ. He went back to the same type of work,
incidentally, but with a respirator. The particular man had been
working at a job where nobody thought he had a lead exposure. He was
working in the forming room, normally a wet room, but he was the one
man in the department who was dropping dry plates into a battery
case. He did not show up for examination until he got sick. We did
not like that; we like to be able to put our finger on these cases of
impending intoxication three or four months ahead of time.
I think I should
like to close with the statement that there is no short cut to
clinical medicine. As Dr. Mayers has said, every single case has to
be viewed as a whole, from the viewpoint of general differential
diagnosis, and one must study the whole picture, not any one
laboratory finding, not even stippled cells alone. Knowing these
things to be frets, we can, with good conscience, go about our job of
keeping the worker healthy and at work.
CHAIRMAN
BOWDITCH: We are so behind schedule that I think we had better
confine our further discussion to a brief reply by Dr. Lanahan, if he
so wishes. Anything more can be at the end of the afternoon, if we
have time.
DR. LANAHAN:
Dr. Belknap posed several questions in relation to my presentation.
The one that strikes me as most important is whether or not we plan
to use urine lead determinations to make our diagnoses of
intoxication, or resort to other measures. He has touched on the
heart of what I feel is our presentation. The problem of which we
are intolerant in our present program is that it is a diagnostic
program. When we apply our proposed analytical studies as we are
determined to apply them and are faced with a diagnostic problem, we
will admit to ourselves that we have failed somewhere along the line,
foiled in prevention.
Our persuasion to
head in this direction is based on the studies that have been made by
Dr. Kehoe and others who have established the ranges of blood and
urine lead levels that are compatible with health, that are seen in
people with known occupational exposure, accepting these ranges as
our starting point. We hope to keep our people within a range of
lead excretion compatible with such standards. As we see them
working their way above such standards, we hope to make more
extensive studies to catch the bugs in our rapid method. At this
stage we feel that we will be ahead of clinical symptoms and stipple
cell changes. We will be before the stage of diagnostic procedures,
using preventive methods. Dr. Belknap has asked, if urine
determinations will replace physical examinations. As I mentioned in
the preface to my presentation, in spite of, let's say, the abundance
of our medical personnel, we feel that we are not able to watch our
people as intimately as necessary to prevent diagnostic problems.
We are looking for
something which will give us a signpost by which we can have our
fingers on everyone before they become diagnostic problems, and we
hope that our proposed method is the measure by which we may
accomplish this.
When we find groups,
and the individuals within the groups, having excretory ranges above
those which have been declared as compatible with health, we will
resort to our present program of physical examinations and complete
blood studies, repeating them as frequently as we wish. Again, let
me say, when we have a diagnostic problem, we will admit that our
preventive medical program has a hole in it.
Dr. Belknap asked
how soon we can plan to review these people, if it requires one
technician for 30 or 40 determinations daily?
Our present program,
which I have described as involving study of stippled cells,
hemoglobin determinations and personal communications with these
people, entails the entire activity of two laboratory technicians.
We estimate that it takes them 20 minutes for each technician lo do
each laboratory study, which results in the determination of the
hemoglobin and the stippled cell count. We believe urine studies
will involve no greater lime and will require no additional technical
personnel.
Our chemist, who at
present does our lead in air determinations, can oversee the
precision of our laboratory analytical studies, for I do not presume
to be so qualified. I might add this. In Fig. 1, Dr. Belknap
presented to you the picture of an assembly line, with grating in the
floor and the down-draft in the table. Men were wearing respirators.
It is my routine to
accompany the general safety committee which, incidentally, is a
management-labor coordinated committee, in visiting every procedure
throughout both plants once a month. I would love to find that each
time we passed the assembly line and any other process we had, we
would see our men actually wearing respirators, where they have been
issued.
The respirator is
either, obviously, down on his chest or it is in a position where he
can quickly duck his nose under it as we are going by.
We have down-draft;
we have water under the grates, and we have respirators. Our air
levels worry us. We have people getting sick. We are doing what all
of you are doing, and we are not satisfied with it.
CHAIRMAN
BOWDITCH: This seems an appropriate moment to repeat Mr. H. J.
Weber's very excellent definition of the industrial respirator. He
has aptly described this device as "A muzzle type ornament worn
loosely pendant from the neck, used in dirty industries to
distinguish the laborers from the office employees."
I am sorry that we
cannot continue this discussion further at this time, for I know that
there are one or two others who could contribute valuably to it, but
we must get on ...