Occupational and Environmental Medicine

Jones, J. A. L. Vaughan

doi: 10.1136/oem.18.4.241pmid: 14452279

The word “Rehabilitation” has been used in many contexts and in many different ways. In the medical field its interpretation has changed considerably in the period from the years before the first world war to that after the second and the ensuing extensive social legislation which followed the Beveridge Report. Changes in definition, although usually enlarging the scope, do not necessarily mean increased application. The multiplicity of statutory and other agencies which have a part in the method and means of returning patients to full industrial and social contact has contributed to the failure to progress with the changes in definition. Any review of rehabilitation services in this country shows many gaps which are due primarily to a failure by the medical profession as a whole to accept the dynamic philosophy of treatment demanded by rational schemes of rehabilitation and secondarily to the failure of effective co-ordination and integration between government departments, hospitals, general practitioners, public health services, and industry. The prevailing tendency to isolate rehabilitation in the sphere of physical medicine is criticized as an attempt to evade a responsibility which the whole practising profession must accept. The fundamental function of industry in the process and the importance of the role of the Industrial Medical Officer are emphasized. Resettlement in employment is the crux of the whole process of rehabilitation.

Waller, R. E.; Commins, B. T.; Lawther, P. J.

doi: 10.1136/oem.18.4.250pmid: 14004693

As a part of a study of pollution of the air by motor vehicles, measurements have been made in two London road tunnels during periods of high traffic density. The concentrations of smoke and polycyclic hydrocarbons found there are much higher than the average values in Central London, but they are of the same order of magnitude as those occurring during temperature inversions on winter evenings when smoke from coal fires accumulates at a low level. An attempt has been made to relate the concentration of each pollutant to the type and amount of traffic. Both diesel and petrol vehicles make some contribution to the amounts of smoke and polycyclic hydrocarbons found in the tunnels, but in the case of smoke, fluoranthene, 1: 2-benzpyrene, pyrene, and 3: 4-benzpyrene, the concentrations appear to be more closely related to the density of diesel traffic than to that of petrol traffic. The concentrations of lead and carbon monoxide have also been determined, and these are very closely related to the density of petrol traffic. During the morning and evening rush hours the mean concentration of carbon monoxide was just over 100 p.p.m. and peak values up to 500 p.p.m. were recorded at times. Oxides of nitrogen were determined in some of the experiments and there was always much more nitric oxide than nitrogen dioxide. Eye irritation was experienced but its cause was not investigated. The concentration of pollution in the tunnels does not appear to be high enough to create any special hazards for short-term exposures. The amosphere at peak periods may become very dirty and unpleasant and the concentration of carbon monoxide would be sufficient to produce some effect over a period of several hours' continuous exposure. The total emission of pollution from road vehicles must still be small in comparison with that from coal fires, but the effect of traffic on the concentration of smoke, polycyclic hydrocarbons, carbon monoxide, and lead in the air of city streets deserves continued study.

Lee, W. R.

doi: 10.1136/oem.18.4.260pmid: 14463581

The report of a clinical study of 104 electrical accidents which befell 85 men is divided into two parts. Part I enumerates the different types of accidents as flash burn, Joule burn, arc eye, “held on” shock and “not held” shock, physical shock, and death. These are related to the different voltages involved ranging from 240/415 (medium) voltage to 33 kilovolts. There appeared to be no association between voltage and type of injury and no evidence to suggest that any of the voltages are free from hazard. There were 53 cases of flash burn, affecting mostly the face and extensor surface of the hands and arms. The 16 cases of arc eye caused no serious concern. Of the 15 Joule burns all except one occurred at medium voltages in “held on” accidents, the other being associated with an electric shock at 33 kilovolts. The majority of Joule burns affected the flexor surfaces. Part II of the paper deals with the 43 cases of electric shock (passage of current through the body). Thirty of these cases were “held on” to the circuit by the current. It was found that the longer a victim was held on to the circuit the greater appeared to be his chances of developing heart and chest symptoms suggestive of impending asphyxia, and of losing consciousness. Although about half of these men were released by an external agency and others struggled off, a number suddenly became free from the circuit without, they claimed, losing consciousness. This is difficult to explain. Artificial respiration was administered in two cases, one of whom was “held on” and was being asphyxiated. The other case received flash burns only and did not in fact receive an electric shock.

Lawrence, J. S.

doi: 10.1136/oem.18.4.270pmid: 14462995

Sixty-nine male and 103 female workers aged 45 and over in a cotton spinning mill in Bolton, Lancashire were examined clinically for rheumatic disease and had radiographs taken of the hands and feet and of the cervical, dorsal, and lumbar spine. To these were added the male and female cotton workers aged 45 and over from a random sample of the population of Leigh, giving a total of 117 males and 228 females. They were compared with a control group of 117 males and 228 females from random samples in Leigh and Wensleydale who had never worked in a cotton mill. These were matched by age and sex. Rheumatic symptoms as a whole were less frequent in the cotton workers than in the controls and loss of work from rheumatic complaints was less frequent in the male cotton workers than in the male controls. Dorsal and chest pain were more common and caused more incapacity in both male and female cotton workers than in controls. Heberden's nodes were present in 38% of male and 35% of female cotton workers compared with 12% and 22% respectively in the controls. Radiological evidence of osteo-arthrosis was more frequent in the distal and proximal interphalangeal joints of the fingers and in the first carpo-metacarpal joints in the male cotton workers than in the controls. In the metacarpo-phalangeal joints of the fingers, the male cotton workers had much the same prevalence of osteo-arthrosis as the controls but it was more severe. The female cotton workers showed the same osteo-arthrosis joint pattern as the males and had similar prevalences in each joint, but did not differ substantially from the female controls. There was no significant difference between the cotton workers and controls in respect of disk degeneration of the cervical spine, but in the dorsal and lumbar spine there was less disk degeneration in the cotton workers, the difference being greater in the females.

Cremer, Jill E.; Callaway, S.

doi: 10.1136/oem.18.4.277pmid: 13882116

The toxicity of tetra and trimethyl and propyl lead compounds has been studied after their administration to rats and rabbits. The toxicity to rats of tetramethyl lead has been compared with tetraethyl lead when given by inhalation. Both tetramethyl and tetrapropyl lead were found to be considerably less toxic than trimethyl and tripropyl lead. There was evidence of a slow rate of conversion of the tetra to the trialkyl lead forms in rats in vivo. Although there was a distinct difference between the signs of poisoning seen after giving the methyl or the propyl lead compounds the primary site of action for both groups appeared to be the central nervous system. Some biochemical studies using slices of rat brain cortex showed that trimethyl and tripropyl lead inhibited the oxidation of glucose whereas tetramethyl and tetrapropyl lead were a hundred times less active in this respect.

Dick, J. M.; Ellis, R. W.; Steel, J.

doi: 10.1136/oem.18.4.283pmid: 13886175

A method is described for the determination of microgram quantities of lead in small volumes of urine. Recoveries from urine samples of added lead show that the mean results of triplicate analyses will, 19 times out of 20, lie within ±12·5 μg. per litre of the true concentration. The determination of lead in a single specimen of urine may be carried out in three hours.

Gage, J. C.

doi: 10.1136/oem.18.4.287pmid: 13896188

Rats have been exposed for varying periods to an atmosphere containing 1 mg./cu.m. mercury vapour. The toxic effects produced showed resemblances to signs of mercurialism in man. An attempt has been made to study the kinetics of absorption and excretion of mercury from measurements of the amounts excreted and stored in the tissues. The efficiency of absorption of mercury by the rat lung is about 50%. A small proportion is excreted into the gut. After about 10 days of continuous exposure a steady state is reached in which excretion balances absorption. During short exposures the turnover of mercury in all tissues except brain is fairly rapid and most of the mercury is cleared from the body within a week after exposure. The urinary excretion of mercury, during the initial stage of storage in the tissues and the final stage of clearance, shows divergencies from the simple exponential pattern; there appears to be a delay mechanism in the kidney which, in intermittent exposures, may result in the occurrence of peak excretion during periods of non-exposure. After more prolonged exposures the mercury in the kidney appears to be converted to a form which is only very slowly excreted. The significance of the urinary excretion of mercury by man after industrial exposure to mercury vapour is discussed. The rat experiments suggest that single measurements will give only limited information concerning industrial conditions, but that an approximate assessment of the total absorbed during a working week would be obtained if it were possible to make a seven-day collection of urine. Repeated measurements after exposure would yield information on the duration of exposure and would have some diagnostic value.

Byers, P. D.; Gage, J. C.

doi: 10.1136/oem.18.4.295pmid: 13875292

The proportion of respirable particles in dust clouds generated from three samples of precipitated silica has been shown to range between one-quarter and one-third by weight. After a single intratracheal dose of the silicas to rats, chemical analysis shows a progressive disappearance of silica from the lungs, though it is still detectable after 12 months. Some silica appears in the liver and kidneys but in two of the three samples none remains after 12 months. The nature and duration of the lung lesions produced in rats after a single intratracheal injection are described. A mild degree of fibrosis was observed which showed a steady regression with time and was to some extent influenced by the nature of the silica injected. The lesions showed little resemblance to those arising from quartz and were more akin to those produced by non-fibrogenic dusts. Recommendations are made for the precautions to be taken during the industrial handling of these dusts.

Jalili, M. A.; Abbasi, A. H.

doi: 10.1136/oem.18.4.303pmid: 14450973

Poisoning by a fungicide used for seed-borne diseases of cereals, ethyl mercury p-toluene sulphonanilide (Granoson M, Dupont), is described. It affected a large number of farmers and their families who used the dressed seed in the preparation of home-made bread. Many systems were involved, including the kidneys, the gastro-intestinal tract, the skin, the heart, and the muscles, but involvement of the nervous system was the most constant with disturbance of speech, cerebellar ataxia, and spasticity. Mental abnormalities were occasionally observed. Many patients died. The changes in the electrocardiograms are described and illustrated. The importance of effective measures for prevention and the need for further studies of treatment are stressed.

Browne, R. C.; Grieves, D.

doi: 10.1136/oem.18.4.309pmid: N/A