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Medical supervision of workers requires that those persons with previous beryllium disease, other chronic respiratory illness, or abnormal chest x-ray findings be excluded from beryllium operations. The preplacement examination should include a 14 x 17 chest x-ray film so as to establish a base line against which subsequent changes, if any, can be compared. Routine “berylliosis examinations" have been of little help in the control of beryllium disease, and special examinations are probably indicated only after known overexposures or in the event of clinical complaints or weight loss. The regular annual medical examination is desirable, however, and respiratory illness should be gone over in considerable detail. The determination of vital capacity is of no value in the control of chronic beryllium disease, for a ventilatory defect in this illness is generally not demonstrable until the lung is markedly fibrotic and stiffened. As beryllium disease may be related to a hypersensitivity to the element, and since the beryllium patch test may produce sensitivity or, as has been suggested, disease manifestations in already sensitized persons, it is unwise to use this test in screening procedures.
It is to be emphasized that beryllium disease is a systemic intoxication and not a pneumoconiosis. The final word regarding its clinical character, course, prognosis and treatment was not been said, and new data are constantly being collected. The diagnosis of beryllium poisoning rests upon the establishment of beryllium exposure, the presence of beryllium in body fluids or tissue, and the demonstration of consistent histopathological findings. The clinical and radiologie pictures are so protean that they, together with the beryllium patch test, supply corroborative rather than diagnostic evidence.
Because of the delay in the onset of beryllium disease after exposure and as a result of the expanding uses of beryllium and its compounds, physicians concerned with occupational etiologies need to remain aware of the causes, course and therapy of this granulomatous man-made disease. Dr. Hardy's address in Massachusetts General Hospital, Boston 14.
Senator MUSKIE. Our next witness will be Dr. Robert A. Kehoe, of the University of Cincinnati College of Medicine, Cincinnati, Ohio.
Dr. Kehoe, we appreciate your coming here this morning and further enlightening the committee.
Dr. KEHOE. Thank you. Senator Muskie. You may proceed. May I say for the benefit of all of us that you may cover as much of your prepared testimony as you want orally but we will include it all in the record. We don't object to listening to it if you wish to read
STATEMENT OF DR. ROBERT A. KEHOE, UNIVERSITY OF CINCIN
NATI COLLEGE OF MEDICINE, CINCINNATI, OHIO
opportunity of being here. I have no hope whatever of being able to present to your committee other than in terms of documents and published materials, the information that is available on this subject.
I am afraid we would be here the rest of the week if I were to undertake to do this. So that what I shall do is briefly to outline where it appears to me that we stand in this situation at the present time, and refer briefly to the evidence that puts us, in my opinion, in that position; and then refer to you and your committee and its staff the published material on this subject which has been assembled for your use.
There is a much longer memorandum that I should not dare to undertake to present here this morning. A series of reproductions of the material that has been issued in various reports, and publications in this country and abroad have been put together for your benefit, primarily because much of it is very difficult to obtain
It goes back to 1924 and is not readily available in the journals that exist at the present time. Some of it has actually been lost but for our copies.
Senator Mrskie. Is it your intent to make this available for the files of the committee?
Dr. KEHOE. That is right. These volumes have been assembled for the purpose of making this information available. Another copy is available if it would be of any interest.
Senator MUSKIE. Would it make interesting night reading?
Dr. KEHOE. Several nights. It would not be a thousand and one, but it would be several.
I would like briefly to state my own position at the present time, if
It is the purpose of this statement to present briefly the salient facts concerning the hygienic aspects of the occurrence and distribution of lead in the environment of citizens of the United States of America, with particular reference to the contribution made by the use of leaded gasoline.
I am a physician, at present professor emeritus of occupational medicine in the department of environmental health in the college of medicine, University of Cincinnati. I have been a teacher and professor on the faculty of the college of medicine in the department of pathology, first, in physiology, and later and longer director of Kettering Laboratory, which has been concerned with industrial medicine and industrial hygiene from its founding in 1930 until my retirement in 1965.
It still continues. From 1948 until 1965 I was the director of the department of preventive medicine and occupational health, the latter being the area in which the Kettering Laboratory is engaged. I was also the chief medical consultant, with the title and corporate responsibilities of medical director of Ethyl Corp. from 1925 until I retired at the end of 1958, this having been imperative in the early years because I was the only person who was familiar with the toxicology of tetraethyl lead and with the occupational hazards associated with its manufacture and distribution. I continued in this capacity, while maintaining my work in the university.
The impression has existed in certain circles that little information is available on this subject, especially as to matters that relate to the safety of the public.
The fact is, however, that no other hygienic problem in the field of air pollution has been investigated so intensively, over such a prolonged period of time, and with such definitive results. This is not to claim that there are no significant voids in the available information, nor that all of the ultimate answers are at hand.
Nevertheless, it is clear that this specific set of problems has been brought to such a point of understanding, in relation to the public health, as to remove it from the realm of urgency and to consign it into that group of hygienic problems on which a watchful and effective surveillance should be kept. A considerable measure of assur: ance for the future may also be derived from the fact that methods of surveillance have been developed, over the years of investigation, which are characterized by a high degree of technical precision and physiological relevance.
Senator MUSKIE. Is it fair to say, Dr. Kehoe, that what you have just said is at variance with the position taken by the Public Health Service and the position taken by Dr. Hardy this morning, as to the state of knowledge that we ought to have before reaching final conclusions ?
Dr. KEHOE. Not precisely, no, sir. I would simply say that in developing the information on this subject, I have had a greater responsibility than any other person in this country. Since 1924, I and my associates have undertaken to answer the question that relates specifically to the public health.
Our interest has been broader, I may say, more extensive, in the field of industrial health, in which the problem is more serious than it is in the field of the public health. But, with respect to the findings in the field of the public health, I would say, at this point, that we are in the best position that we have been at any time in the 35-year period since leaded gasoline was introduced on the American market.
With respect to the information that is necessary to answer the questions that are available, they are not all answered and there are still investigations to do. But I repeat that the situation is in no sense urgent.
Senator Muskie. With respect to this sentence in your testimony “No other hygienic problem in the field of air pollution has been investigated so intensively over such a long period of time and with such definitive results."—is it your intention that that statement apply to industrial exposure to the problem, rather than to the exposure of the general public to lead in the atmosphere?
Dr. KEHOE. Not at all, sir. The industrial exposure is with us, it is a hazard. Lead poisoning in industry is still one of the most frequent occupational diseases with which we are presented in this country despite the fact that we know how to prevent it.
The question with respect to the public has been from the very start, from 1923 on, hypothetical, a potential risk which we have been undertaking to measure by every means which we can get at, and the evidence at the present time is better than it has been at any time that this is not a present hazard.
Senator MUSKIE. May I ask a further question on this? The Bureau of Mines and the American Petroleum Institute have just entered into a contract involving $480,000 of American Petroleum Institute money to conduct research in this field. Is that in your judgment a reflection of concern or simply routine?
Dr. KEHOE. Not with respect to lead. The concern here is with other aspects of the use of petroleum hydrocarbon fuels, which do present us with a series of problems some of which are unsolved.
Senator MUSKIE. I understood the contract does relate to lead.
Dr. Kenoe. It relates both to leaded and unleaded gasoline, with the idea of establishing whether the lead introduces an additional factor in the behavior of the hydrocarbons. There is no question however about the factor of risk of a sort from the petroleum hydrocarbons. The question at issue here which is being carried out along with the general investigation is whether lead enters into this problem and in any way affects the matter disadvantageously.
Senator Muskie. Would you say that, from the point of view of health it would be desirable, if not urgent-you have indicated it is not urgent-but from the point of view of health would it be desirable if a substitute for lead could be found for gasolines?
Dr. KEHOE. If by this means one could accomplish the same purpose—and mind you, I am not interested in the economics of the matter other than in the avoidance of upsetting the whole community, this is not my concern—there is nothing at the present time that would say to you or to me that we should hurry to eliminate lead from the gasoline in the country.
There is no evidence that this has introduced a danger in the field of public health. There is still the hypothetical question, and this is largely because we have long known that lead has the potentiality of grave danger, that it produces illness, that it still produces illness.
We have known only for a relatively short time, since I may say the work of the Kettering Laboratory in this field, that lead is an inevitable element in the surface of the earth, in its vegetation, in its animal life, and that there is no way in which man has ever been able to escape the absorption of lead while living on this planet.
This has always been the case and it will continue to be so despite our efforts. The question therefore is how much danger is there; how much does it take to create danger, and what is the margin of safety that exists at the present time between, that is, what would be dangerous and what is certainly not dangerous?
Senator MUSKIE. I am not certain you have answered my question, so I would like to ask it again.
Dr. KEHOE. I am not avoiding it. I am just trying to give you a full answer, sir.
Senator MUSKIE. I understand. Putting aside the question of economics, which we both agree should be put aside, if you have a nontoxic substitute for lead that would do the same job that lead does would you think it desirable from the point of view of health to make the substitution.
Dr. KEHOE. I should be indeed very cautious in arriving at any such conclusion. I would not be able to arrive at it, without investigation in advance of the fact. If investigation demonstrated the truth of what you have just said
Senator MUSKIE. I have asked you to assume the truth of what I have said. Obviously it is hypothetical and the record will be clear on that point.
Assuming the truth of what I have said, assuming in fact you had such a substitute, would you say from the point of view of health that the substitute ought or ought not to be accepted? Because then the only question involved would be economics.
Dr. KENOE. Yes, I am only saying I cannot make such an assumption, because there would have to be information on the various materials that have been recommended--that have been thought of in this connection, as substitutes for tetraethyl lead. None at the pres; ent time has turned out to be satisfactory, and none has been devoid of certain considerations in the field of public health which would have to be answered.
Now, I would only take this position. We have had experience with tetraethyl lead since 1923 which clearly indicates, to me, that it is not a
present hazard. We would not have that kind of information in relation to any other material that I can conceive of as being put in this capacity, and therefore, I am careful about the answer to your question.
If I could assume that everything is perfect about it, which I cannot do, then I would agree with you.
Senator Muskie. I think that is a hypothetical question you can make that assumption. Frankly I am disturbed that you are not sure enough about the body of knowledge upon which you are relying to answer such a hypothetical question.
As I said clearly, assuming as a fact-recognizing it has yet to be established as a fact-assuming as fact there is a substitute or there could be developed a substitute for lead that would do the same thing for gasoline that lead does, but without any toxicity, any toxic effects, would you say from the point of view of health that it would be desirable or not desirable to make the substitution?
I think that is a question that a man with your background like this ought to be able to answer.
Dr. KEHOE. I could answer it except that I take the point of view, as a matter of principle, that we must investigate every material that we introduce into our environment
Senator MUSKIE. I do not quarrel with that. Dr. KEHOE (continuing). Because there are unknown effects. Now to answer your question, if I could be quite sure that this was the case, I would be glad to dispense with a risk, the question of risknot the question of hazard because I think it does not exist—but the question of potential hazard, which is risk. I would be glad to trade any risk for the certainty of safety.
Senator MUSKIE. All right. I guess that is as close as we can come together.
Dr. KEHOE. The bulk of the investigative work which bears on lead in the general environment of man has been carried out, under the financial sponsorship of the manufacturers and distributors of lead containing antiknock compounds in the United States, in the Kettering Laboratory, in the Department of Preventive Medicine and Industrial Health of the College of Medicine of the University of Cincinnati, and under the terms of agreements between the executives of the industries concerned and the board of directors of the university, whereby the public responsibilities of the university have been preserved intact. This Department has been renamed, recently, the Department of Environmental Health.
Facts brought to light by these investigations have been confirmed by evidence derived from the examination of similar situations by official investigators in other countries, and from extensive tangential applications of the methods of our investigations, principally to the
When an investigation, undertaken jointly by the U.S. Public Health Service, and the health departments of the city of Philadelphia and the State of California and the Kettering Laboratory, was completed, and the results were published, in 1965, under the title of a “Survey of Lead in the Atmosphere of Three Urban Communities," these being Philadelphia, Los Angeles, and Cincinnati, the reliability of the past and current information, as well on the lead content of the atmosphere of cities, was established beyond further question. It is now possible