EFFECTS OF RADIATION FROM FALLOUT

1254 the

puerperium. Here, too, no rapid improvement likely, since in many cases there are no warning signs. 36 of the deaths occurred during pregnancy, 66 after vaginal delivery, and 27 following cassarean

pregnancy

or

is

section. Future reports will have more to say about such deaths: a special inquiry form has been introduced for maternal deaths ascribed to pulmonary embolism or venous thrombosis. Improved antenatal care has contributed to a reduction in deaths from toxaemia; but, even so, avoidable factors were found in 51 of the 104 deaths in this group. In some cases the patients concealed their pregnancies, or failed to seek medical advice, or refused to enter hospital, or discharged themselves against advice. In other instances there was inadequate antenatal care, or confusion of medical responsibility, or inadvisable booking for a general-practitioner unit or for home confinement. Despite the rise in birth-rate, deaths from haemorrhage fell from 130 in 1958-60 to 92 in 1961-63; but some doctors have still to learn that it is dangerous to move a shocked patient from home to hospital without preliminary blood-transfusion; several women who lost their lives in this way might have survived had the flying-squad been summoned to their homes. Heart-disease (81 deaths) continues to be a formidable complication of pregnancy, particularly in older and in multiparous women. Nothing short of the very highest standard of care throughout pregnancy, labour, and the puerperium will reduce the number of these deaths: those affected should not be confined at home or in generalpractitioner units (as in several of the fatal cases). And doctors must see to it that these patients and their husbands are fully aware of the extra risks and, where necessary, are helped to plan their families. There will always be irresponsible patients-many examples are given in this report-but most husbands and wives, if properly informed, will collaborate fully. A special section is devoted to the booking arrangements that were made for patients included in the inquiry. Some patients, despite advanced age, high parity, or a history of medical or obstetric complications, were booked for confinement in places lacking equipment and staff to deal with emergencies. Other patients, when complications were transferred from their homes to small units with inadequate facilities, whereas immediate admission to a consultant unit should have been arranged. It is estimated that there were avoidable factors in 37-9% of all the deaths. Responsibility for these avoidable factors lay with consultants as well as with family doctors, and in a high proportion of cases the fault lay exclusively with the patient herself. There can be no doubt about the pressing need for further education of doctors, midwives, and patients and their relatives. These valuable reports should be drawn to the attention of all doctors and nurses who deal with obstetric cases, and it would be a great help if they were given publicity in the Press, on the radio, and on television. Here, as elsewhere in medicine, advance will come largely through the application of what is already known. And what of the future ? The four reports that have already appeared have contained a great deal of information that has led to reappraisal of the maternity services and to improvement in medical care and its organisation. The number of deaths is falling steadily, and this may now be the time to pass from a regular threeyearly report to a more detailed examination of certain

arose,

hazards-e.g., pulmonary embolism, abortion, ectopic

and amniotic-fluid embolism-based on information collected over a longer period. And these confidential inquiries would be even more valuable if all medical officers of health could be persuaded to collaborate in the investigation of maternal deaths in the areas for which they are responsible. pregnancy,

EFFECTS OF RADIATION FROM FALLOUT

INCREASING information about the risks of damage to health by low doses of radiation has made it possible to reassess the possible effects on populations of fallout from nuclear test explosions. Such a new evaluation has now been made in a report1 to the Medical Research Council by its committee on protection against ionising radiations. The basis for estimating risks is taken from new data submitted to the International Commission on Radiological Protection, which are expressed as the numbers of additional cases of leukasmia, of thyroid cancer, and of all fatal cancers taken together that might be expected over and above the natural incidence if a population of one million persons was exposed to 1 rad of radiation to the whole body or a substantial part of it. 1 rad is about ten times the average annual background dose. The available information now suggests that, after one million people had been exposed to this hypothetical dose, a total of 20 additional cases of leukaemia might arise, spread over the next ten to twenty years. All other fatal malignancies 20 increase another cases. Study of the effects might by of therapeutic medical irradiation of the thyroid in children suggests a risk of 10-20 additional cases of thyroid cancer in a population of one million exposed to 1 rad. The natural incidence in the United Kingdom of all types of fatal cancer (including leukxmia) is at present about 2200 cases per million per year. What are the actual doses from the products of test " explosions ? The report estimates " dose commitments for people in Britain-that is, the total doses that they will ultimately receive from fallout resulting from all weapon tests carried out up to the end of 1965. These estimates refer to the country-wide average for persons living throughout the entire period 1954-2000. The commitments for the important fallout nuclides (other than 131I)

were:

Thus, the total commitment to bone-marrow of rather less than 0-15 rad would be associated, on the basis of the I.C.R.P. risk estimates, with not more than 3 additional cases of leukarmia; and, on an estimated whole-body commitment of 0-1 rad, the number of additional cases of fatal malignancies other than leukxmia would be of the order of 2 per million. Finally, the assessment of the risk of thyroid cancer is put at not more than 2 cases per million (the mortality from this condition would be less 1. The Assessment of the Possible Radiation Risks to the Population from Environmental Contamination. H.M. Stationery Office. 1966. 1s. 9d.

1255

than this and

was

included in the estimate for fatal

malignancies). The total dose to the gonads of members of the present generation from the fallout of all tests up to 1965 " will not exceed about 0-1rad ". Many later generations will be subjected to very low doses from the long-lived 14Cto a total additional dose of about 0-2 rad. The estimate of genetic risk is 1 additional case of visible genetic abnormality in the offspring of each million persons exposed. The report discusses counter-measures that might be taken against fallout-the substitution of dried for fresh milk (particularly for infants), the use of an ion-exchange process for the reduction of 90Sr and 137CS concentrations in milk, and the administration of extra calcium in the diet to inhibit the uptake of 9"Sr. It seems unlikely that any large-scale and prolonged countermeasures against the somatic effects of radiation could be more than partially successful. Protection against the genetic effects would be still more doubtful since they are attributable primarily to external radiation as well as to ingested 13’Cs. It is also noted that some hazards to health could be associated with the remedial measures themselves and that the scale of any such possible ill effects cannot be estimated in the present state of knowledge. The report concludes that it is not feasible to specify fixed radiation levels at which appropriate countermeasures should be instituted. Any decision about remedial measures could be taken only when the radiation risks from particular nuclear tests in the atmosphere could be estimated.

VIRACTIN: THE DEBATE CONTINUES

Two years ago, Leach and his colleaguesreported clinical trials of a distillate of the fermentation products of Streptomyces griseus which they called " viractin ". When evaporated into room air, this substance apparently reduced the incidence of minor upper respiratory disease and of influenza. In laboratory tests there was no evidence that the material inactivated viruses and it acted in mice only after very large doses were given intranasally; the conclusion was that its effects in man showed that it prevented viruses attaching to and multiplying in cells. We were not entirely satisfied with the design of the clinical trials,2 and now an independent group has studied the activity of viractin supplied by Leach’s group and failed to find any antiviral activity.3 They explored the proposition of Leach et al. that viractin interacted with cells and prevented infection, and they found that small doses of representative strains of rhinoviruses (a frequent cause of common colds), influenza and parainfluenza viruses, and adeno-viruses could multiply in cultures exposed to concentrations of viractin near the maximum tolerated by the HeLa cells used. Moreover, cultures of ciliated cells maintained in the same concentration of viractin produced full yields of influenza virus. Mice infected with influenza A were kept in a room where the air was treated with viractin, but they survived no longer than mice in a normal room, and virus sprayed into such air was not inactivated faster than in normal air. In view of these results Tyrrell and Walker thought there was too little evidence to justify trials in man, but Leach4 attacks this view. He points out that certain useful drugs, such as digitalis, quinine, and cycloserine, 1. Leach, B. E., Hackman, P. E., Byers, L. W. Nature, Lond. 1964, 204, 2. Lancet, 1965, i, 37. 3. Tyrrell, D. A. J., Walker, G. H. Nature, Lond. 1966, 210, 386. 4. Leach, B. E. ibid. p. 387.

788.

would not be regarded as suitable for trials in man on the basis of tests in animals. This is, of course, true, but these three must be contrasted with the large number of newly introduced drugs, ranging from tranquillisers to antibiotics, the activity of which was demonstrated in vitro and in animal experiments before they were subjected to clinical trial. At least some experienced workers who select substances for clinical trials would doubt whether it is justifiable to make extended trials of viractin in man. Perhaps a small and intensely observed group could be studied. The odds against viractin being able to prevent respiratory disease seem to be heavier than when we last discussed the matter-but it is probably a subject on which one should not gamble.

FAMILY PLANNING AND THE PHYSICIAN

THE concept of ideal family size varies from country to country and from one generation to the next, but family planning is an almost universal intention-some methods admittedly being far from successful. In a lecture at the Postgraduate Medical School of London last week, Prof. J. R. Willson, a gynxcologist from Michigan, said that the physician has a special responsibility to help his patients have exactly the number of children they want. He cannot dictate how many children a couple should have, for this must remain a personal decision for the parents, but he can help them to reach a decision and to implement it. It is surely an anachronism that medical students receive no formal training in family counselling, and this is why so few doctors volunteer advice about birth control. Yet many patients are reluctant, for one reason or another, to seek expert advice on contraception, and the doctor is in a unique position to help. A good time to approach the patient is at the postnatal examination, and three simple questions-" How many more children are you going to have ?" " When are you going to have the next ?" and " How are you going to work it ?" - will get all the information required about her attitude

towards, and knowledge of, contraception. The physician should be familiar with all types of contraceptives, but to help his patient fully he must know her as a person. A woman might ask for an intrauterine device because her friend is using one, but a little questioning might reveal that she dislikes the idea of something " inside " her. What she really wants is advice, and she might do best on " the pill ". All methods of birth control have a high discontinuance-rate, which is quite often due to emotional dissatisfaction rather than physical discomfort. This can be uncovered only by patient and sympathetic inquiry. An unconscious need for pregnancy is a fairly common reason for irregular use of contraceptives, but one that is not

always easily recognised.

Intrauterine devices have been used for some years as a cheap and reasonably effective method for population control in developing countries, but they are now becoming popular in more affluent societies. Between a quarter and a third of all devices inserted are soon discarded (for reasons other than desire for pregnancy), but those retained are effective. Even so, the protection-rate could still be improved. Careful insertion is particularly important, for extrusion is more likely if the uterine wall is damaged. An incidental but important finding is that a device inserted 10-12 weeks post partum has a greater chance of success than one fitted at 6-8 weeks. Of a series