Document jyabo0e2REGKQQL1140LVKzVp

THE LANCET, JUNE 29, 1974 1323 menses to produce v.c But unreacted v.c which is present in newly manufactured p.v.c may be released during storage and when the material is heated during manufacture ofp.v.c. products. Compounding processes known as dry blending, Banbury/2 roil THE LANCET mill compounding, extrusion compounding, and paste mixing, and fabrication processes such as extrusion, calendering, and paste spreading may be C y " - associated with release of v.c into the atmosphere. Carefully planned ventilation at appropriate points in pTv.c processing plants is therefore recommended. Vinyl Chloride, P.V.C., and Cancer The reaction of food-packaging experts is still awaited. By the time p.v.c sheeting is used for At the end of 1972 a man of 71 died in the Victoria Hospital, Blackpool, from a rare form of neoplasia, angiosarcoma of the liver. He had worked for 20 years as a process worker making polyvinyl chloride (p.v.c) from vinyl chloride (v.c). The derails of the case are given by Dr La and Dr Hamt on p. 1316: according to them, this is the nlwgnrh case of its kind, though die first in die United wrapping food its v.c content is probably low and very little may find its way into food or into the atmosphere of the food supermarket or domestic kitchen. Nevertheless, information is needed. At the very least the public should be told--if it is true--that the grades of P.v.c used for wrapping food are pretreated to remove as much free v.c monomer as possible. Kingdom. Cases of hepatic angiosarcoma in men To date, all those workers who have developed exposed to v.c have been previously reported in angiosarcoma of the liver have a history of inter die United States of America,1 Sweden, and mittently heavy exposure to v.c over 'periods of Germany. ffomT2 to 27 years in p.v.c-manufacturing plants. The reaction of experimentalists to die situation There have been no cases among P.v.c processors. is to ask why nobody heeded die results of work on Most examples of heavy exposure date back to the rats, published in 1971. Violo and his colleagues a early days of P.v.c manufacture before certain reported the occurrence of cancers which were other, non-cancerous, health hazards associated with later found to have arisen in the acoustic duct, exposure to v.c were recognised. Raynaud's and cancers of the lungs, bones, and other sites in phenomenon (acro-osteolitis) in response to v.c was 17 out of 25 rats exposed to 30,000 p.pja. v.c for repotted as early as 1957*-*; more lately, chronic 20 hours a week. The answer may be that, ln some liver poisoning leading to portal obstruction, hl*erfig eyes, experimentalists have too often cried " cancer- from oesophageal veins, and splenic enlargement wolf" on quite inadequate evidence of real hazard. were identified as v.c effects. Their discovery led In any case it could have been argued that 30,000 to ever-increasing efforts to protect workers from p.p.m. is very high in comparison with human exposure to v.c Nobody knows how many more exposure levels to v.c in most p.v.c-manufacturing cases of v.c-induced angiosarcoma of the liver will plants in 1971. The reaction of the Department rtf' come to light. Optimists will argue that the con Employment Factory Inspectorate has been to set a ditions in industry have so greatly improved that we new interim upper limit for exposure to v.c in may already have seen the worst., Pessimists, how p.v.c manufacturing plants at 50 p.pjm. with a ever, will say that we have so far probably seen only maximum time-weighted average exposure of 25 those cases with the shortest latent interval resulting p.p.m. However, these limits will almost certainly from the heaviest exposure, and that an epidemic of be lowered in view of Cesaxs Maltoni's chum to cases with longer latent intervals associated with have produced angiosarcomas of die liver by exposing lesser exposure is yet to come. Moreover, an effect rats to only 50 p.p.m. v.c (reported on May 10 at a of v.c on die incidence of certain less rare forms of meeting organised by the American Cancer Society cancerjmay so far have- passed. unnoticed. Whatever and New York Academy of Sciences). The reaction happens, 'die v.c. episode will have provided a of the manufacturers, through the Chemical Indus salutary lesson. It will not be quite so easy in the tries Association Ltd., has been to pool their experi future, as it has been in the past, for any chemical ence and resources in the production of a guidance manufacturer to assume, until proved otherwise, document for P.v.c processors.* Thereis no indica that a chemical to which workers are exposed is tion that p.v.c is itself dangerous or that rtjlepoly-1 2 3cartinogemcally safe. There most surely be moresys- 1. Crwch-i. L-aiStatPOscevp. Mtd. 1974, W, 150. 2. Violo, r. L., BifOCti, A.* Cftputo, A. Comm* 1971, SI, 510. 3. Vinyl Chloride Monomer: Advisory Note for the Guidance of PVC Proce--ort. Published by Chrmiral Industrie* Aaaodaden Ltd., Alembic House, 93 Albeit Embenkmem, London SE1 7TU, June 12, 1974. 4. Low, D., Orwnbws. L. A, Ado, W. R. Am. mL Hyt. Aa. J. IMS, 24, VA. 3. Luce, C E., JOb*. 3., Sctin, G,, VctaoaiwG. /. Arch. Aitmamtd. ,1974. 32, 1. 6. JQhc, S,, Lan*, C E., Sewn, G., VtUmaa, G. Ot. awi. Wwftr. 1974, 94 2034. BFG23153 1324 THE LANCET, JUNE 29, 1974 remade evaluation. of industrially used chemicals have had exposure to some specialties, and it enables for cardnogenic risk to workers. In its own area, the specialist surgeons to gain experience in fields other thalidomide disaster was a milestone. YinyNchloride than their own and general surgery. One hopes angiosarcoma is a milestone in occupational hygiene. that, in time, there may be a move towards the specialist f.r.cs. for more surgeons, as already applies in Canada and Australia for almost all the accepted specialties but in Britain is available only Specialisation in Surgery for ophthalmology and otorhinolaryngology. This should reduce the need for specialists to spend some Sir Charles Illingworth 1 once declared, in a of their, intellectually speaking, most productive somewhat whimsical address, that general surgery had no future. The Joint Committee for Higher Surgical Training set up by the Royal Colleges has yean working in spheres largely irrelevant to their ultimate careen. Earlier specialist work might provide a solution recognised eight specialties; and now general surgery to another problem, which b the limited amount of styles itself the ninth (or first). In fact, almost half research carried out in the surgical specialties. When the surgeons in Britain are in a recognised specialty a major funding body lately discussed why thb other than general surgery. Institutional inertia has, however, ensured thar both colleges and universi should be so, it was told that the prolonged training periods required for specialists left young men with ties still act on the assumption that surgery really little time for diversions into research; also that the means general surgery. Most undergraduate reaching limited academic establishment in the specialties is still carried out in so-called general surgical was a disincentive to research-minded surgeons in wards, although in teaching hospitals many of these training, who mostly opted for general surgery are highly specialised. But when it is suggested that (which offered a number of senior university posts students or preregistmion house-officers should to which they could aspire). Although, some chain spend a major part of their surgical time in specialist in orthopedic surgery have been established, other units there is talk of these being unsuitable. It is specialties have had to be satisfied with throccasional difficult to see why, if it is accepted that the'oduca- personal chair, which often does no mbrc than donal purpose at this stage of training b to expose acknowledge the local pre-eminence of an established young minds to the principles and practice of and largely clinically oriented surgeon. Shch a surgery in general, rather than to general surgejy. personal chair provides no sound basb for a pepper This means becoming familiar with preoperatfop department and it provides no substructure \or assessment, doling with die patient and his family;, promotional ladder for younger academic surgeons, liaison with the anesthetist and nursing staff, post- \ because there b no assurance that a vacancy will, operative care, and the like. Technical details of what ' arise in the future. The solution lies in the hands of ' happens in the operating-theatre are of little con the professors of (general) surgery. Already several sequence at tins stage, so what is the essential younger ones are malting specialists welcome in then educational difference between one surgical specialty research laboratories and are anxious to include and another ? Undergraduates would want to spend them in their wider academic teams. A few have some rime with abdominal and acddeot/orthopcdic surgeons, but beyond this electives could be organised created specialist academic departments headed by professors, or by senior lecturers with some to complete the surgical component' of die practical independence; but many more have proceeded to curriculum. At the postgraduate level the failure to acknowledge make seapnd chairs in general qurgery. Certainly no medical school would want chairs in all eight specialist that general surgery is only one among many branches ^nor b the University Grants Committee specialties has a more serions effect. Still imprisoned likely to thb kind of pluralism). But it would by the regulations for the " general " vjlcs., all benefit surgekv in general if each school had two or surgeons must complete a considerable time in three specialist chain, chosen according to the general surgery and then face an examination largely particular opportunities and facilities already existing organised by general surgeons. One proposed locally. Thb would provide a reasonable career training scheme for surgeons begins no sooner than structure for youhger academics in die specialties, two years after qualification and permits rotation to would enable serum and continuing research pro specialties only after 2 years' continuous training grammes to be supported, and would strengthen the in general surgery. ' A more balanced attitude b school of surgery in tfiat particular university. Thb evident in two other regions which allow for 18 strengthening would beMnore likely if the academic months each in general surgery and in the other departments of surgery in a university were grouped specialties, with alternating periods of 6 months in into a division of academic surgery--to borrow a general and in specialty surgery. Such a scheme useful administrative term from the National Health ensures that those who will become general surgeons1 Service. In such a division the specialist professors 1. Illingworth, C. Scca. mod. J. 1942,7,1. should be expected to contribute fully to the task of BFG23154