Document 341KwJQgR0eNZQeQ1VVgGbzn

FILE NAME: Welding (WELD) DATE: 1936 Apr 1 DOC#: WELD001 DOCUMENT DESCRIPTION: Journal Article - X-Ray Appearances of the Lungs of Electric Arc Welders 'IB B LANCET] D B S. D O IG & M CLAUGHLIN : LUNGS O F EL EC TR IC ARC W EL D E R S [APRIL within an hour or two; hut this degree of acidity was 'not invariably maintained throughout the day. we are both of about average weight (10 st. 2 lb. dnd 10 st. 91b.) wo concluded that somewhat larger doses should generally be given for the treatment of patients. Four patients were treated with ammonium mandelate, and in all four a sterile urine was effected jn a week or less, though all had a chronic infection. Case 26, a man of 13 st., required doses of 51 grains four times daily (loz. of the elixir). Case 27, a child of 6 (weight 3 st. 7 lb.) with acute nephritis as well as B. coli infection, was given 17 grains four times daily. Case 28 had 34-grain doses. In Case 29 the urine was alkaline to litmus before treatment, and 51-grain doses supplemented by 30 grains of ammonium chloride were necessary to produce a satisfactory acidity and cure the infection. In the light of this short experience, together with what is already known of mandelic acid treat ment,' we feel justified in saying that ammonium mandelate, suitably prepared, is a convenient means of administering mandelic acid, and that in the majority of cases the use of ammonium chloride can thereby be obviated. The suitable dose of ammonium mandelate is probably the same as that of the sodium salt--namely, about 50 grains four times in the day, the equivalent of about 3 grammes of mandelic acid. TREATMENT OF PYELONEPHRITIS IN GENERAL The disease " pyelitis " affecting, as it does, the parenchyma of the kidney as well as the renal pelvis, ureter, and bladder, is better known as pyelonephritis. The term cystitis may be restricted to the occasional infection of the bladder only, by catheter or other wise, before an ascending spread has taken place. Acute pyelonephritis is often associated with high temperature, rigors, and general symptoms of which severe headache is one of the most frequent. For such severe cases, alkalis if given in sufficient .doses are so efficient in bringing down the temperature and controlling the distressing symptoms that we have not used mandelic acid therapy, fearing to cause a temporary exacerbation of symptoms or to induce vomiting. It should be noted that it is often necessary to give as much as 30 grains of potassium citrate and 30 grains of sodium bicarbonate every two hours in order to produce the effect. We have recently seen two patients in whom the pyrexia remained despite an alkaline urine, until the dosage was pushed to this extent. When the acute stage has been controlled, a few cases rapidly clear up spontaneously, especially in women after delivery. In many more, however, pus cells and bacilli remain in the urine, and a chronic pyelonephritis develops. Often there are acute exacerbations and for years the patient suffers from poor health and has intermittent attacks of frequency, dysuria, pyrexia, or urticaria. A few eventually develop renal failure. As nearly all these chronic infections are now avoidable, we would like to stress the importance of not discharging any case of pyelonephritis, especially when acute, until it is known that the urine is sterile. If, after an acute attack has settled down, bacilli are still present, mandelic acid therapy should be employed at once, before waiting for chronic changes to develop. For those who show a marked tendency to recurrence we are trying the effect of giving two consecutive days of mandelic acid treatment in each month. Between these brief courses, fluid intake should bo liberal, and both constipation and the over-use of aperients should be avoided as far as possible. SUMMARY Of 29 cases of urinary infection treated with mandelic acid 24 showed sterile 'urine within 2-21 days. Of the successful cases 2 had also a con current nephritis in an active stage, which was not adversely affected by the treatment. Of the 5 failures at least 3 were unsuitable cases in which cure was not to bo anticipated. Ammonium mandelate was found to be as effective as the sodium salt, and when it was used it was usually unnecessary to give the unpleasant ammoniumchloride. The proper use of these remedies will prevent chronic pyelonephritis. REFERENCES 1. H elm holtz, H . F ., and C lark, A. L. : P roc. Staff .Meet. Mayo C lin., 193i, v i., 605 a n d 609. 2. F u ller, A. T . : T h e L ancet, 1933, 1., 855. 3. Rosenheim , M. L . : Ib id ., 1935, i., 1032. 4. L yon, D. M ., a n d Dunlop! D. M . : B rit. Med. J o u r., 1935- il,, 1096. X RAY APPEARANCES OF THE LUNGS OF ELECTRIC ARC WELDERS By A. T. D oig, M.B. St. And., D.P.II. MEDICAL SU PERINTENDENT, OAKWOOD HALL SANATORIUM, ROTHERHAM ; AND A. I. Gr. McLaughlin, M.B. Sydney, M.R.C.P. Lond. H .M . MEDICAL INSPECTOR OP FACTORIES, HOME OFFICE (w it h il l u s t r a t io n s on p l a t e ) A t t e n t io n has been directed recently to the acute pulmonary conditions which may occur in welders as a result of their occupation. Adler-1lemnark1 in 1929 described the illness and death of an electric arc welder from pulmonary oedema which he attributed to nitrous fumes. In 1934 Bridge 21 recorded a number of cases of acute poisoning by nitrous fumes occurring in oxy-acetylene welders who were working in a confined space in a ship. Williman's recent case3 of acute fatal pneumonia in an electric arc welder was that of a man who had been welding galvanised iron in a confined space; and Titus, Warren, and Drinker 1 have shown after a series of animal experi ments that the pulmonary oedema associated with welding (not necessarily of galvanised metal) in confined spaces is caused by the gases (nitrogen peroxide and ozone) generated at the electric arc and not by the fine particles of iron oxide found in the fume. The symptoms associated with the welding of galvanised metal appear to be comparable with those'of metal fume fever and were described by Bridge2b in 1921, by Koelsch in 1923,5 and also by Drinker 0 and his co-workers in 1927. Similar symp toms in welders working on galvanised metal have been noted by Dickson 7 and by Anderson.8 Metal fume fever is a transient malady and is characterised mainly by malaise, pyrexia, and shivering attacks. Some ,of the occupational risks in welding--e.g., metal fume fever and poisoning by nitrous fumes-- are common to both electric arc and oxy-acetylene welding, but each method has its proper risks. Wirtschafter and Schwartz9 state that the oxyacetylene welder is exposed, under various working conditions, to poisoning by the products of incomplete combustion of the oxy-acetylene flame, especially 772 THE LANCET] D E S . DOIG & MCLAUGHLIN : LUNGS OP ELEC TR IC ARC W ELD ER S [APRIL 4, 1936 carbon monoxide and acetylene, and also by impurities in commercial acetylene. Westhofen,10 who made a statistical study of tbe health of 146 electric arc welders, shows th at a large number of them suffer from colds and inflammatory conditions of the upper respiratory tracts, a fact which he believes can be explained by the irritating properties of the metal fume and by the sudden changes of temperature to which welders are exposed. Chronic pulmonary lesions directly associated with the occupation have not been recorded up to the present time as occurring in electric arc welders. This fact is not surprising because the process is a comparatively new one and it is only during the last ten years that it has been widely adopted. I t may be noted also th at covered electrodes have only been used for about ten years. We present in this paper the results of a clinical and radiological examination of the chests of 16 electric arc welders. They are apparently healthy men and are actively engaged at their occupation. Nearly all of them are young men who were apprenticed to electric welding at 14 years of age and who have worked at no other trade. The X ray films of 6 of them show a generalised fine mottling over both lung fields; the remaining films show less marked changes, but none could be considered to be a picture of a completely normal chest. The conditions which have to he considered in the differential diagnosis include miliary tuberculosis, asbestosis, silicosis, and other pulmonary conditions caused by dust or fumes. Tbe X ray film in the first case, in view of the family historv ,was for some time thought to be an example of miliary tuberculosis. In tbe present early stage of the investigation we are not prepared to be dogmatic about tbe interpretation of tbe radiographic and clinical findings, especially because no opportunity for histological examination of the lungs has arisen. In this paper we merely wish to record the results of our examinations as far as they have gone and to discuss in a general way the possible factors in the cetiology. THE FIRST TWO CASES Ca se 1.--Aged 44. This man was seon by one of us (A. T. D.) at the Rotherham Tuberculosis Dispensary on June 28th, 1933, because his sputum had been stained slightly with blood for a few days. He felt well except for slight debility which had followed an attack of influenza six months previously. Family History.--ft is father and grandfather, both of whom had been 'tin miners in Cornwall, had died from silicosis. Occupational History.--He left school at 14 years of age and for 1 year stoked boilers in a clay mine {above ground). For 18 years (until 1925) he worked as a black smith, but during this time lie had done occasional electric welding jobs. He has been an electric are welder for 11 years. X Ray and Other Examinations.--On June 28tli, 1933, an X ray film showed fine mottling * evenly distributed over both lung fields. The sputum was oxamined on July 4th, 1935, for tubercle bacilli and for asbestos bodies, with negative results. The glass shield used by the man to protect his eyes during electric welding was examined on Sept. 29th, 1933, at the Govornmont laboratory. The report stated that " the fume deposited on the glass con sists essentially of magnetic iron oxido (Fe30 4). Slight evidence of the presence of silica was obtained but this was probably derived from the glass slide, the surface of which was damaged by red-hot particles thrown off from the electrodes." Further X ray films were taken of his chest on Dec. 26th, 1933, and also on Sept. 3rd, 1934 * We have used the word " nodule " as a convenient term to describe the individnal shadows without reference to their size. " Stippling " is -used to indicate the very line " riodulaiion " seen in several cases, whereas " mottling " is used to describe a coarser type of " nodulatiou." (Fig. I. on Plate). The appearances differed in no essential point from those of the original film. I t was thought however that the punctata shadows soon in the later film wore slightly larger, especially in the fifth right costal space closo to the hilum. The patient has not lost any time from work and when seen recontly was found to be in fairly good health. Since 1933 he has been wearing a mask over his nose and mouth during actual work at electric welding. Physical examina tion rovoaled few abnormal signs with the exception that the breath sounds were harsh over the apices and bases of the lungs, and that a few post-tussic cropitations could be hoard at both bases. The movement of the chest was equal on both sides but the degree of expansion was some what limited. Ca se 2.--Aged 35. This man was asked to attend for X ray examination because of the nature of his work. His occupational history shows that after leaving school lie worked in an office for 6 years; for another 3 years lie was engagod in a steel works as a cold steel roller, and for the 11 years ho has been working continuously as an electric are welder. For the last year he has been working as storekeeper because he thought the fume from welding was affecting his health. There is no family history of tuberculosis. He has a slight cough and occa sional morning sputum, but otherwise is in good health. He was first radiographed in September, 1934, the film (Fig. II. on Plate) showing features similar to those of Case 1. The lung fields generally show a fine mottling, the individual shadows being irregular in size and having soft outlines. The mottling is distributed fairly uni formly, although the upper two-thirds of each lung field are rather more affected than the lower thirds. Both lungs are equally affected. A recent radiogram of the chest (Jan. 6th, 1936), taken a year after he had given up electric welding, shows th at the mottling noted in the first film is still present but less marked. In some of tbe larger nodules a minute central core is visible. Clinical examination of tlio cliest shows that the expansion is equal on both sides but is rather less than normal. The percussion note is not impaired, and the breath sounds are harsh with prolongation of expiration over both lower zones, especially in the mid-axillary lines. Post-tussic crepitations are hoard at both bases. Examination of the sputum (March 12th, 1936) shows that it contains largo numbers of macrophages or dust colls which are packed with fine granules of iron oxide. No asbestos bodies are seen. On. account of tlie findings in the first 2 cases, 14 more welders were asked to attend for examination. Brief notes of the history and of the results of the X ray examinations of the chest are given. In a few cases the results of clinical examination of the chest have been added. FOUR " POSITIVE " CASES Four showed X ray appearances comparable with those seen in the first 2 cases, and are therefore classed as positive. Case 3.--Aged 25, Electric arc weldor for 9 years. No other occupation. No family history of tuberculosis. Has a slight cough with copious black sputum, especially after welding inside tanks. Movement diminished over the left upper part of tho chest. No impairment of percussion noto. Breath sounds harsh over left upper region and also at both bases posteriorly. Crepitations were heard at both bases in tho axillary linos but more cloarly on tho loft sido. Radiography (Jan. 6th, 1936). Skeleton, heart, and diaphragm normal. Shadow of lung roots not onlargod. Prominent (? calcified) opacity in the upper pole of left root. Fine bronchial ramifications slightly accentuated generally. Fine stippling throughout both lung fields, the nodules being irregular in size and shape. The stippling is slightly more marked in the upper half of tho right lung. Case 4.--Agod 23. Electric welder for 7 years. Health good and no family history of tuberculosis. Slight cough with morning sgutum. Radiography (Jan. 8th, 1936). Skeleton, heart, and diaphragm normal. The shadow of the right hilum is definitely enlarged. The if' W*- 'j s & E LANCET] 1M m is. D O IG & M C L A U G H L IN : LU N G S O F E L E C T R IC ARC W E L D E R S [APRIL 4, 1936 7 7 3 bronchial markings arc not increased. Over both lung fields there is generalised stippling. The nodules aro irregular in size and shape and consist of single and ' aggregated units. Their outlines are soft but some of the larger ones have a hard central core. Case 5.--Aged 26. Electric arc welder for 9 years, gad an attack of acuto bronchitis 5 years ago, since when has had a persistent cough with black sputum. -Radiography (Jan. 8th, 1936). Skeleton, heart, and diaphragm normal. Bronchial markings prominent. Bight lung clear. Over the upper half of the left lung fine stippling is seen. Both hilar regions normal. Case 6.--Aged 28. Electric arc welder for 12 years. Health good. No symptoms apart from slight cough and sputum. Examination of the chest shows that the expansion is good and equal. Percussion note good, Breath sounds well transmitted with a slight prolongs tion of the respiratory murmur. No adventitious sounds Heart sounds normal. Radiography (Jan. 15th, 1936) Skeleton, heart, and diaphragm normal. Bight inter lobar septum visible. Generalised fine stippling through out both lung fields, the shadows being irregular in size and having soft margins. THREE " SU SPICIO U S" CASES . Three more oases showed X ray changes which were not so definite as those presented by the first .6 cases. We havo classified them as suspicious. . Case 7.--Aged 26. Electric arc welder for 9 years. ; No other occupation. No family history of tuberculosis. Has had a cough with morning sputum on and off for v" 10 years. The cough is worse after he has done a welding, job in an enclosed space, and the sputum then becomes black. Finds that he gets very tired, especially on night shifts. Radiography (Jan. 6tli, 1936). Skeleton, heart, and diaphragm normal. The bronchial shadows are accentuated generally in both lung fields. There is fine ' stippling distributed over the left upper zone, especially hV' in the area immediately surrounding the upper polo of the left root. Case 8.--Aged 25. Electric are welding for 11 years. No family history of tuberculosis. Has only a slight ' oough which is worse after working in an enclosed space, and brings up a certain amount of black sputum mainly In the mornings. Examination of the chest revealed no abnormal physical signs. Radiography (Jan. 6th, 1936). Skeleton and heart normal. Bight dome of diaphragm slightly blurred. Slight enlargement of thehila, especially on the left side. There is only a slight increase in the ^bronchial trunk shadows, but the fine bronchial ramiP'!t fications, especially in the mid-zones, present a honeycombed appearance. A few faint soft and fairlv coarse nodules are present in both lung fields. Those are mainly *^fitatd peripherally and give a coarse mottled effect. The mottling in this case is not nearly so well marked, l^i\: aor the nodules so fine as in the definitely positive casos. away from work for a week. Has a slight cough with morning sputum. Radiography (July 13th, 1934). Heart rathor bulbous and slightly enlarged to the right. The right dome of the diaphragm is elevated, and the right costophronic angle obliterated. The shadow of the left hilum is enlarged. The bronchial trunks in both lungs are markedly accentuated. Close examination reveals a suggestion of fine stippling in the upper lung fields, but this feature is not definite. Case 11.--Agod 23. Electric arc welder for 9 years. Healtli good and no family history of tuberculosis. Has no symptoms. Radiography (Jan. 8th, 1936). Skeleton, heart, and diaphragm normal. Bight interlobar septum very faintly soon. Fine bronchial ramifications show a slight honeycombing but no definite nodulation. An appearance of nodulation is present, especially in the third and fourth right intercostal spaces as a result of the crossings of the fine bronchial ramifications. Case 12.--Aged 25. Has been an electric arc welder for 10 years. Ho altondod the dispensary because his wife was suffering from open pulmonary tuberculosis. Has no cough or sputum. Radiography (March 18th, 1933). Skeleton, heart (small), and diaphragm normal. Bronchial shadows not definitely increased in the lower zones. A slight degree of stippling is present in the second right intercostal space and also in the second and third left intercostal spaces. Case 13.--Aged 23. Electric arc welder for 81 years. No otlior occupation. No family history of tuberculosis. Has no cough as a rule, but brings up black sputum after doing electric welding inside tanks or boilers. Radiography (Dec. 23rd, 1935). Skeleton, heart, and diaphragm normal. Bronchial markings generally intensified. No dofinito stippling present. In certain areas--e.g., the fifth right and fifth loft intercostal spaces--the lung paren chyma shows a fine " honeycombing." Case 14.--Aged 31. Electric arc weldor for 3 | years. Health good. No symptoms. No family history of pulmonary tuberculosis. Examination of tho chest shows no abnormal signs. Radiography (Jan. 15th, 1936). Skeleton normal. Loft auricular region of the heart shadow appears to be enlarged. Increased bronchia^ striation but no parenchymatous mottling. Ca se 15.--Aged 27. Electric arc welder for 11 years. Health good. Slight cough and sputum. Examination of the chest reveals no abnormal physical signs. Radio graphy (Jan. 15tli, 1936). Skeleton, heart, and diaphragm normal. Slight increase of bronchial markings but no parenchymatous stippling. Case 16.--Agod 32. Electric arc welder for 9 years. Health good. Slight cough and sputum. Clinical exami nation showed no abnormal physical signs. Radiography (Jan. 15th, 1936). Skeleton, heart, and diaphragm normal. Definite increase of bronchial striation with very slight fine honeycombing but no definite stippling of the lung parencyhma. CASE 9.--Aged 22. Electric are welder for 8 years. 'Health good, and only has a cough after doing welding 'iniide a tank. Radiography (Jan. 8tli, 1936). Skeleton, heart, and diaphragm normal. Bronchial shadowing is jf?; Prominent in the right upper lobe, and some calcified a! Bjjfiules are present in the right liilum and upper periv/. -hilar area. Fine bronchial ramifications are increased ngwwrally, and both lung fields have a slightly stippled ^ JPpoarance, the nodules being poorly defined and well '.[<spaced. Actual nodulation is however present, it'*. - ,, if!).'. Ra d io g r a ph ic a l ly n e g a t iv e " cases DISCUSSION The diagnosis of the underlying pulmonary lesions which have given, rise to these striking X ray changes is a matter which is both interesting, and in the absence of histological examination of the lung tissue, highly speculative. Little doubt exists, how- ` ever, th at the lung changes have been brought about in those men by the dust or fume which they have inhaled while working as welders. During welding operations dense white or greyish-white fume rises ,, ^*6 remaining 7 cases have been classified as )?*J8*tive from a radiological point of view. It will , however th at a number of the films showed ||mcrea8od bronchial striation or fine honeycombing to definite mottling, and could not strictly Called normal X ray films of the chest. M IP---Aged 41. Oxy-acetylono welder for 3 years ir~ "1* apprenticeship, and electric arc welder for r* family history of:tuberculosis. Had a ", tack of influenza '2 years ago which kept him up continuously from the spot which is being welded. The welder is obliged to bend closely over his work because he holds in front of his face a coloured glass screen which protects his eyes from the strong light but impedes his vision. If no protective measures 'are adopted, the welder cannot fail to inhale large quantities of fume during the time ho is actually working. ' I'ko electrodes or welding rods which contain a core of metal and an outer covering are consumed Hoi* 4  ; . 774 t h e l a n c e t ] d r s . d o ig & m c la u q h lin : lu n g s o f e l e c t r ic abo w e l d e r s ' [a t b il 4, lda'Jf gradually by the heat generated (about 1500 C.) during the welding operation. The metal in tho core of the rod becomes molten and, assisted by the flux contained in the covering, spreads over the surface of the metal which is being welded. The fume is therefore made up of the volatilised consti tuents of the coverings of the rods together with fine particles of oxidised metal, usually in the form of iron oxides. In addition the fumes probably contain gases such as nitrogen peroxide and ozone which are formed by the action of an electric spark on the air. The composition of the coverings of the electrodes or welding rods becomes, in the circum stances, a matter of some importance. Many substances, all of which we do not propose to enumerate, are used. The basis of'.the majority of the coverings is sodium silicate which acts as a flux. Again, the coverings of a certain type of electrode contain asbestos. The rods are sometimes dipped in a mixture containing powdered asbestos and sodium silicate, or asbestos yarn is wound round the rod and fixed by sodium silicate. In some cases the asbestos completely covers the rods, and in others it is merely a cord which is wound spirally about tho rod. The composition of the fumes arising from electric welding electrodes has not yet been fully investigated. Mr. L. C. McNair, H.M. Engineering Inspector of Factories, has however had partial analysis made of the fumes evolved from an asbestos-covered electrode and some asbestos fibres were found. When the particulate matter of the fumes was collected in an Owen's dust-counter, it was seen that a large proportion consisted of iron oxide particles, with an occasional asbestos fibre. The X ray appearances in the well-marked cases differ from the usual picture of asbestosis. In none of the positive cases and in only one of the suspicious cases was there any blurring of the diaphragmatic ^shadow, and in no case was the heart outline blurred. The line of the interlobar septum (a feature present in a number of films of cases of asbestosis) is seen in only one positive case. The opacities in the films are not accentuated at the bases of tho lungs, but on the contrary the upper lung fields appear to be the earliest, and in established cases, most markedly affected. Before asbestosis can be eliminated from the differential diagnosis it must be remembered that the asbestos fibres are being subjected to intense heat and are not in the same physical state as the fibres which are inhaled by workers in an asbestos factory. I t is possible that an atypical picture of asbestosis might be produced by the inhalation of altered asbestos. Merewether 11 says that--- " the radiographic appearances of tho developed or advanced stages of asbestosis are distinctive, although they are not specific. While, as is tho case with silicosis, certain radiographic appearances may bo looked upon as typical of the disease, frequently modifications of and departure from the typical picturo occur." f DESCRIPTIONS OF ILLUSTRATIONS ON ' ^ COLOURED PLATE '! V- DR. MANSON-BAIIR A. ---Ac u t e B a c il l a b y D y s e n t e r y . Shiga's bacillug) isolated. General oedema of mucosa, spasm, sub-' mucous haemorrhages. Early healing stage. B. --Ch r o n ic B a c il l a r y D y s e n t e b y . Flexner-Y infec-"f tion. Agglutination test positive to Flexner 1 ; 180.!i Great improvement on intestinal lavage. C. --A mcebic U l c e b a t io n of lo w e r r e c tu m g iv in g rise to sym ptom s suggestive of carcinom a. D. --Amcebic D y s e n t e b y . Chronic stage, showing " pit- ting " of mucous membrane. E. -- A c u t e A mcebic D y s e n t e b y . A c tiv e u lc e r a tio n of m ucosa w ith blood and m u cu s ex u d ate. ' F. ---In t e s t in a l B il h a b z ia s is . E a r ly stage. Patches of. granulation, tissue containing eggs of Bilharzia mansoni. G. --Mucous Co l it is. Showing the pale colour of the mucosa and the masses of adherent mucus. ; H . -- A c u t e U l c e r a t iv e Co l it is . First stage. Usually called haemorrhagic colitis. I. -- A c u te U l c e b a t iv e Co l it is . Showing plum-coloured, \ easily traumatised, mucosa in the second stage. J. -- A c u te U l c e b a t iv e Co l it is . Early stage, showing granular mucosa, with purulent exudate covering the surface. Note the lack of normal folding of the mucosa. K. ---Ul c e b a t iv e Co l it is . th ird , or ulcerative stage. Superficial ulceration in the L. -- T u b e r c u l o u s U l c e b a t io n o p R e c t u m . Case in which tubercle bacilli were found in material obtained through the sigmoidoscope. The patient was suffering from chronic diarrhoea with blood and mucus in the stools.*1234 and bis health at the present time is good. None of the men suffers from dyspnoea. Secondly none of them has concomitant pulmonary tuberculosis. Miliary tuberculosis can - be ruled out of the differential diagnosis for clinical reasons, and to some extent on the radiological appearances. None of the cases shows the dyspnoea, cyanosis, and tachy cardia of acute or subacute miliary tuberculosis. Chronic or healed miliary tuberculosis is rare and it is difficult to imagine that a condition of such rarity would be found in 6 out of one group of 16 men. In the X ray films of the welders' chests (see Plate) the fine opacities are irregular in size and shape, whereas in miliary tuberculosis of the lung the shadows are more uniform. A further possible explanation of the X ray appearances in this series of cases is that the inhalation of small quantities of nitrous fumes together with tho superadded effect of fine iron oxide dust might set up small areas of chronic inflammatory change, congestion, or fibrosis in the lungs. Again, the iron oxide particles might be opaque to the X rays and produce the picture without the associated presence of fibrosis and congestion. The X ray appearances in our cases most closely resemble those of a fine silicosis, hut the clinical features show two important differences. In the first place, the electric welders whom we examined are all in good health and are fit to work. The only symptoms observed were slight cough and morning expectoration, and in the first case a small hmoptyeis occurred. This man has not been away from work even for a day since he was first seen in June, 1933, SUMMARY 1. The chests of 16 electric arc welders who have been engaged at tho trade for periods varying from 6-16 years have been examined radiologically. 2. In 6 cases th X ray films showed fine nodulation over both lung fields ; in 3 cases stippling was present o v e r a m o re limited a r e a ; tho remaining cases showed varying degrees of accentuation of the bronchial shadows, but no stippling. In no ease was a com pletely normal radiogram obtained. t W e have su b m itte d our films to D r. M erew ether an d he Is 3. Clinical examination of the chests revealed of th e opinion th a t " while some of th e films give a general impression of asbestosis, further exam ination reveals so m any few abnormal signs. h points of difference in detail from the currently accepted radio- 4. The alterations in the pulmonary or bronchial v graphic appearance of asbestosis, as to negative such a diag nosis." ' tissues underlying these X ray changes have been DESCRIPTIONS OF ILLUSTRATIONS ON PLATE DUS. DOIG AND MCLAUGHLIN FIG. I.-- Radiogram showing the line m ottling discovered in Case 1 (Septem ber, 19114). T he p o rtio n outlined in w hite is reproduced (as an inset) on a larger scale. is the purpose of this communication to record the results of experiments of oven longer duration. Cramer and Horning 3 have reported the appearance of hminorrhagie chromophobe adenomata of the anterior pituitary in 3 male mice of a scries of 12 receiving external applications of oestrone dissolved FIG. II.-- R adiogram from Case 2 (Septem ber, 1931). in chloroform for prolonged periods, up to 44 weeks; DR. MCE.UEN, D ll. SELYH, AND PROF. COLL11* many of their animals showed cachexia, atrophy of the spleen FIG. II.--High m agnification of endom etrium showing m eta plasia into cornifiod squam ous epithelium . The islets of squamous epithelium in the suhm ucosa are derived from deep prolongations of- tu b u lar endom etrial glands. N ote the m arked fibrosis of th e endom etrium which sim ulates sear tissue. FIG. IV.--H istological picture of a p a r t of th e tum our shown in Fig. I II . Large cavernous sinuses surrounded by anterior lobe tissue. and thymus, and degenera tive changes in the adrenal c o r t e x -- elfects which t hey ascribe FIG. V.-- Sm all adenom a in th e an te rio r lobe of a n oestrintreated r a t ; probably first stage of tum our formation. The cells in th e area of the adenom a are m uch larger th an those of th e surrounding p itu itary tissue. in part to hypopituitar ism. Simple FIG. VI.--Small adenom a of th e interm ediate lobe of th e pituitary of an eestrin-treated rat. Note the irregular structure of the posterior lobe with light dots corresponding to vacuolised cells. enlargement of the pituit ar y was FIG. VIII.--Scirrhous llbro-adenom a of the m am m ary gland in an oestrin-treated rat. observed i n 8 of their series of 12. set up by the inhalation of fume which arises (luring tIht atis thkenoawdn ele5c.tric Tarhce wperoldbinabg.le composition of the fume has beenm inistration discussed. of l a r g e d o sos o f C. We wish to emphasise th at these X ray appearances have been found in men who are oistriu t o apparently in good health. ' female rats may load to con7.cluUspiontoasthtoe thpereesxeanctt dtiimagenowsies ohfavthee ccoomndeititoon.no hypertrophy of tho an FIG. I.--T ransverse soctlon across th e REFERENCES terior lobe uterus of eestrin-treated rat. . Note the enormous development of fibrous tissue 2. A dler-IIerzm ark, J . : Z e n trlb l.f. GewerboUyg., 1929, vi., 193. within a few in tb e subm ucosa which leads to partial obliteration of the uterine cavity. The 2. B ridge, J . C. : (a) A nn. H ep. Chief In sp ecto r of F actories, days,4 a n d epithelium show s no m etap lasia in th is Hom e Office, 1934, p. 08 ; (b) A nn. H ep. Chief Insp ecto r that this is case. of Factories, 1921, p. 70. 3. W illim an, F. L. : Jo u r. Iiu lu st. H y g ., 1935, xvii., 129. a ccom - 4. T itus, A. C ., W arren, I I., an d D rinker, P. : Ib id ., 1935, panied by enlargement, probably secondary, of x v ii., 121. the adrenal cortex ; hut these changes were much 50.. KDorienlskoehr,, PF.., :T hIobmids.o, n1,9K23.-2M4.,, va.n,d87F.in n , J . L. : Ib id ., 1927, less marked in males or in castrates. ix ., 331. Six castrate female rats, initially 3-4 months old, 7. Dickson, A. : B rit. Med. Jo u r., 1935, i i ., C02. received daily subcutaneous injections of 30 y of 8. A nderson, H . : Ib id ., 1935, ii., 040. cestrone, dissolved in corn oil, for 331 days; vaginal 9. W irtsck aftcr, Z. T ., an d S chw artz, E . D. : Jo u r. In d u st. H y g ., 1930, x v iii., 158. (estrus was maintained, with very rare lapses, through 10. W esthofcn : Z eits. f. M edizinalbcam tc, 1934, x lv ii., 85 (Abs. Jo u r. I n d u s t. IIy g ., 1935, x v ii., 13). 11. M erew ether, E. I t. A .: T ubercle, 1933, xv., 78. out tiiis period. The animals were sacrificed after a further 30 days, during which all (save one) were either left untreated or were injected with solutions of crystalline progesterone (corpus luteum hormone), SOME EFFECTS OF / PROLONGED ADM INISTRATE and in either case had returned more or less rapidly to an anoostrus state. The progesterone-treated animals did not differ materially from those in which OF (ESTRIN IN RATS all treatment had been discontinued. By C. S. McEuen, M.D. RESEARCH ASSOCIATE IN BIOCHEM ISTRY, MCGILL UN IVERSITY, MONTREAL H. Selye, M.D., Ph.D. ASSISTANT PROFESSOR OF BIOCHEM ISTRY IN THE UNIVERSITY J AND At post-mortem examination the horns of the uteri were found to ho nearly solid, pearly white, and hard ; histological study revealed an extreme hypertrophic fibrosis, pushing the mucosa and mus cular coats aside and enlarging the volume of the organ (Fig. I.). Squamous metaplasia of the epithe J. B. Collip, Ph.D., D.Sc., M.D., F.K.S. PROFESSOR OF BIOCHEMISTRY (WITH ILLUSTRATIONS ON PLATE) lium was present in five eases (Fig. II. on Plate). These alterations in the uteri were also observed in biopsy .specimens taken between the 300tli and 330tli day of treatm ent; occlusion of tho cervix with secondary pyometrium was not encountered in The discovery that the continued administration this series. of cestrono, subcutaneously, led to squamous meta plasia of the uterine epithelium of castrate female rats 1 has been confirmed and extended by further experiments reported elsewhere2 in which treat ment was continued for periods up to 132 days. It The pituitarios were enlarged, in all cases, and large cavernous adenomata of the anterior lobe were present in three; one showed a small adenoma of tho intermediate lobe, and vacuolisation of the posterior lobe was noted several times. In one case o 2