Occurrence of oral and pharyngeal cancers in textile workers

Moss, E. and Lee, W. R. (1974).British Journal of Industrial Medicine,31, 224-232. Occurrence of oral and pharyngeal cancers in textile workers. The occupations of male textile workers who died of oral and pharyngeal cancers in the five years 1959-63 have been examined to discover whether the high incidence of oral cancer in these workers noted by the Office of Population Censuses and Surveys (1972) is associated with particular textile occupations or fibres. There was a 77% excess of deaths from these cancers in male textile workers as a whole compared with the male population of England and Wales, the excess being significant at the 0·1% level. An excess occurred in each of the three sites tongue (ICD 141), mouth (ICD 143, 144), and pharynx (ICD 145-148) and is significant at the 5% level in the first two sites but not in the third. Fibre preparers had an excess of 330% which is significant at the 0·01% level. Weavers and knitters had a deficit of 32% and the remaining three groups had moderate excesses of from 32 to 85%, none of the four being statistically significant. In the 1951 census there were 8 414 male cotton workers and 14 723 male wool workers engaged in fibre preparing. There was one death from oral cancer in cotton fibre preparers and 18 deaths in wool fibre preparers. The difference is significant at the 1% level. The difference is also significant for the individual sites pharynx and tongue but not mouth.

Erythrocyte phagocytosis in the human trabecular meshwork

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Emergence of occupational medicine in Victorian times

Lee, W. R. (1973).British Journal of Industrial Medicine,30, 118-124. Emergence of occupational medicine in Victorian times. The events surrounding the establishment and development of legislation to protect the health of people at work in Victorian times are already well documented. This paper deals with some other aspects of the development of occupational medicine.

Medical opinions at the time did not always see the misuse of child labour as due simply to avaricious mill owners, but in part due to the parents and in part to the workmen subcontractors. The establishment of the certifying surgeons is briefly reviewed and their coming together to form an association in 1868 may be related to questions about the need for medical certificates of age which were being requested by the many factory owners brought under factory legislation for the first time in 1864 and 1867.

The plight of injured workmen and their dependents was early recognized, although it was late in the Victorian era before any statutory provision was made for them. The idea of linking compensation with preventive measures came to the fore in 1845 when some Manchester doctors, later supported by Edwin Chadwick, examined the workings at the Woodhead railway tunnel across the Pennines. When compensation legislation was passed some half a century later the idea was lost, and to this day compensation for and prevention of industrial injury and disease remain separated.

The change of industrial diseases from a medical curiosity to a problem requiring State intervention is traced over the latter part of the Victorian era.

The whole piecemeal pattern illustrating the precept that `social problems come first, social philosophy after' has persisted until the far-reaching changes in health and safety legislation of the present day.

An anatomy of occupational medicine

Lee, W. R. (1973).British Journal of Industrial Medicine,30, 111-117. An anatomy of occupational medicine. Previous writers have attempted to describe occupational medicine by considering the functions of a doctor working in industry. In different communities, and even in the same community at different times, a doctor working in industry may have different functions. `Occupational medicine', so described, would therefore not be a discipline but would merely be medicine practised in a certain area. Furthermore, such an approach leaves out other aspects of occupational medicine such as recompense for injury at work and statutory supervision of workplaces, and any interaction between these two.

Men think in terms of conceptual models which predetermine to a greater or less extent their approach to future problems. The present essay attempts to formulate a coherent intellectual framework of occupational medicine.

The conceptual model proposed here is based on the globe proposed by Himsworth (1970) as a model representing the structure of scientific knowledge. Using this, a place for occupational medicine can be determined related to medicine, industry, and the `basic' sciences. Occupational medicine is thus seen as a coherent entity.

The argument is supported by a comparison of some of the provisions for occupational medicine in this country and in France. In this comparison the underlying components are distinguished from the mechanisms set up to deal with them. It is these components which go to make up the structure of occupational medicine and it is the coherence and close relationship of them which must be studied to find and describe an entity to be called occupational medicine.

Ventricular fibrillation threshold for AC shocks of long duration, in dogs with normal acid-base state

Scott, Janet R., Lee, W. R., and Zoledziowski, S. (1973).British Journal of Industrial Medicine,30, 155-161. Ventricular fibrillation threshold for AC shocks of long duration, in dogs with normal acid-base state. Earlier experimental studies of threshold ventricular fibrillating currents passing along the common accident pathway of forelimb to leg have shown a wide range of results for any one shock duration. In the present investigation the acid-base state of the experimental animals (dogs) was held within normal limits. It was found that whereas the mean minimum fibrillating current, 82·2μA for 3-second shocks, was within the values found by other workers, the range of results was reduced considerably to 67-101μA. Further, when the shock duration was increased, in stages, up to 60 seconds, again keeping the acid-base state within normal limits, the mean minimum fibrillating current did not alter markedly (being 80μA at 60 seconds) but the range of results progressively fell and was 73-88μA at 60 seconds. In the light of these findings the mechanism of ventricular fibrillation is discussed.

Prediction values for the ventilatory capacity in male West Pakistani workers in the United Kingdom

The ventilatory functions (forced vital capacity, forced expiratory volume in one second, and peak expiratory flow rate) of West Pakistani immigrants working near Manchester were measured. There were 198 `normal' healthy adult workers aged 25 to 60 years and 129 workers aged 16 to 24 years. The subjects were considered `normal' if they did not admit to persistent cough and phlegm. The regression equations on age and height for the two groups are presented together with the corresponding nomograms for the adult group.

Ventilatory function reached its maximum between the ages of 25 and 30 years; smokers and dust-exposed subjects did not differ significantly from non-smokers and non-dust-exposed subjects (P>0·1). This was probably due to their relatively light smoking habits and the short duration of dust exposure. The effects of age, in workers over the age of 25 years, and the predominant effects of height on the FVC, FEV_1·0, and PEFR are similar to those found in other studies.

The ventilatory capacity of the subjects was found to be somewhat lower than that of Caucasians, about equal to that of Negroes living in America, and higher than that of Indians of Asian origin living in Guyana or of Bantu Negroes in South Africa.

The predicted FEV_1·0/FVC% in the West Pakistani subjects is a little higher than any calculated from the results of other authors, but its regression on age is consistent with the findings of other studies and, therefore, can be used in clinical practice to assess the pulmonary conductance.

Scrotal cancer in the north-west of England, 1962-68

Lee, W. R., Alderson, M. R., and Downes, J. E. (1972).Brit. J. industr. Med.,29, 188-195. Scrotal cancer in the north-west of England, 1962-68. During the seven years 1962 to 1968 there were 103 cases of scrotal cancer reported to the Manchester Regional Cancer Registry. It was possible to obtain reasonably full occupational histories concerning 89 of these cases either from the men themselves or from close relatives. Fifty-one had been mule spinners, 40 of whom had worked in no other industry with a hazard of scrotal cancer, but the other 11 had. Another 19 men had never been mule spinners but had worked in occupations with a recognized hazard of this condition. Of the remainder, 14 had worked in occupations with a possible risk, although perhaps not generally recognized as such, and in five no clear cause was apparent. Because of the small numbers, it was possible to compare the observed and expected incidences only in broad occupational groups and these showed a statistically significant excess (P<0·001) only in textile workers and unskilled workers. However, our findings, taken with those of earlier workers, suggest that further attention might be given to four other groups, namely, automatic lathe operators, road workers, dye workers, and chain makers. Cancer of the scrotum tends to be a disease of the elderly. In 42% of men (other than mule spinners) scrotal cancer developed after the men had passed the age of retirement and therefore too late for routine medical examination at the workplace to be of any value. Fifty of the men had died, but scrotal cancer was registered as the underlying cause in only 19 and appeared on the death certificate in a further four.

Experimental studies with a clinical monitor and diagnostic computer

A clinical monitor and computer is described which uses input information about heart rate, blood pressure and oxygen saturation. The data are processed in a simple diagnostic computer, the circulatory failure analyser, to give a diagnosis of cardiac arrest, hypoxia and oligaemic shock and to give early warning of tachycardia, bradycardia, hypertension, hypotension and cyanosis. The analyser was tested on simulated signals and experimentally in animals. The validity of the logic utilized by the computer was confirmed and the sensitivity as a monitor was assessed.

The hazard of electrocution during patient monitoring

The ever-present hazard in patient monitoring is electrocution resulting in ventricular fibrillation. Fire and explosion hazards are possibilities but seem to be very remote.

Iatrogenic electrocution can occur when:

(a) more than one piece of electrical equipment is connected to the patient.

(b) the distal end of an intracardiac electrode is handled.

(c) pericardiocentesis is carried out with ECG monitoring,

Under these circumstances, small currents, of the order of 100-200 μA, may cause ventricular fibrillation. There is evidence that the ventricular fibrillation threshold is substantially lowered by anoxia and acidosis but it seems to be unaffected by barbiturate anaesthesia.

This paper suggests that the physician or surgeon should understand the risks but may need the expert advice of an electrical engineer. Ventricular fibrillation which has occurred under these circumstances requires careful, expert investigation to establish whether or not it was electrically induced.

Effects of pulsed currents on respiration and the heart

The effects on the respiratory and circulatory systems of rabbits of pulsed currents from two sources have been studied. The sources were an industrial high voltage test-set (source A) and an automobile ignition system (source B).

When the fore-limb to fore-limb pathway was used, source A produced complete arrest of respiration at the highest output voltage, 5kV (corresponding to a current of 392 mA), and at a pulse repetition rate of 30 per second. Progressive reduction of either of these factors resulted in progressively less interference with respiration. With the fore-limb to hind-limb pathway complete arrest of respiration occurred at an output voltage of 2 kV (corresponding to a current of 140 mA) and at a pulse repetition rate of 30 per second. Again progressive reduction of either current or pulse repetition rate resulted in progressively less interference with respiration, although at 30 per second even with the lowest voltage setting (1 kV; 64 mA) only diaphragmatic respiration occurred. Source B used on either pathway up to a pulse repetition rate of 16 per second did not cause complete arrest of respiration whether the current was taken straight from the ignition coil or off the distributor.

Neither source caused ventricular fibrillation either when delivering pulses at a preset rate or when the pulses were timed to coincide with successive T waves of the E.C.G. In these experiments the trains of pulses falling on the T waves lasted about 10 seconds.

With both sources the current and voltage waveforms were similar and in phase. With source A increase in current was directly related to increase in applied voltage. These findings suggest that under these experimental conditions, with minimum contact resistance, the animal impedance is resistive with no significant reactance.

Fatal fungal infection following open-heart surgery

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In vivo survival of the endothelium of freeze-stored corneal homografts in the rabbit

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Mule spinners' cancer and the wool industry

Although mule spinning has been used in the cotton and wool industries for about two centuries, the earliest recorded cases of mule spinners' cancer were not reported until the end of the nineteenth century. From then on the number of cases rapidly increased. Evidence accumulated which strongly suggested that the mineral oil used to lubricate the mule spindles was the cause. It is remarkable that mule spinners' cancer was almost entirely confined to the cotton industry, and the wool industry has escaped with very few cases. This difference has never been satisfactorily explained. Various possibilities related to the personnel, the plant, and the process are examined in this paper.