In order to evaluate the use and handling of acrylic bone cement, questionnaire were presented to all Danish orthopaedic departments in 1987 and again in 1992. Marked improvements in the environmental safety precautions for handling of bone cement had taken place during the 5-year period. In 1992, the intraoperative handling and use of bone cement is thus generally considered safe. Further improvements are still to be advocated in some departments. The exposure to methylmethacrylate monomer (MMA) vapour during the cementation procedures should be eliminated by local punctual field suction or change to a bone cement with a lower content of monomer (MMA/n-decylmethacrylate/isobornylmethylacrylate bone cement). Unnecessary manual contact with the cement should be avoided, and if contact is necessary, special protective gloves (butyl rubber gloves or 4H-gloves) should be used in addition to ordinary surgical gloves.

By use of a methylmethacrylate (MMA) Dräger tube and bellow bump, the breathing zone concentrations of MMA monomer were measured for the operating surgeon during cementation of the components of hip and knee joint prostheses. The highest recordings (50-100 p.p.m.) were encountered during cementation of the acetabular cups with conventional polymethylmethacrylate cement. Such exposure could be eliminated by the use of personal protection equipment, local punctual field suction or change to a MMA/n-decylmethacrylate/isobornylmethacrylate bone cement.

A questionnaire was given to all participants of the Wonderful Copenhagen Marathon 1986 regarding demographic information, health, training, previous injuries and methods used to prevent these. A total load of 2158 Danish runners participated and 1426 (68 per cent) replied. Fifty per cent of the runners were training 30-60 km per week and 25 per cent more than 60 km per week. Forty-one per cent were members of running clubs. The runners were equally distributed between all social groups. Most runners were slim (mean BMI 22.3 +/- 1.87 (SD)), healthy, non-smokers who rarely suffered from serious injuries, but 31 per cent had had injuries that prevented them from training during the last year. Nearly all performed stretching exercises and methods to avoid injuries. Fifty per cent of the runners tried to optimize their performance by changing their diet in the days before the run. Seventeen per cent used the classical high carbohydrate diet and 33 per cent other special diets.

Sudden death in highly trained athletes during organized competitive exercise is very infrequent, considering the large number of participants" 2. Sudden death in marathon running has been described3 but few reports have tried to relate sudden death during vigorous exercises to age4'5. We report a previous healthy 56-year-old man who had a cardiac collapse Iduring the 'Wonderful Copenhagen Marathon' 1987. He was a highly trained athlete who had completed eleven previous marathon races and never been treated for cardiovascular disease. After 36 km of the race he suddenly collapsed without warning. Resuscitation was initiated at once and the race medical staff reached the patient after three minutes. Ventricular fibrillation was diagnosed and DC defibrillation was successful. On hospital admission ten minutes later he was alert, cardiovascularly stable and denied any chest pain prior to collapse. Coronary enzymes were slightly elevated (CKMB, LDH) and ECG was compatible with an inferior subendocardial infarction. Echocardiography was normal. The patient was discharged uneventfully after four days. Although cardiac enzymes are increased with physical streSS6, permanent ECG changes even without chest pain favour the diagnosis of myocardial infarction7. When reviewing the literature and the above mentioned case it is our impression that the cause of sudden death in exercise is mainly due to silent ischaemia among competitors over 35 years old. Maron et al. have described causes of sudden death in competitive athletes and concluded that in athletes over 35 years old 75 per cent of sudden deaths were related to arteriosclerotic heart disease. They rarely resulted from the congenital heart conditions more common in younger athletes' deaths. They stressed that about half of older patients with sudden deaths had prodromal cardiovascular symptoms or a known medical history of coronary artery disease and were described as having 'severe' coronary narrowing at autopsy. The other 50 per cent were asymptomatic45. Marathon running itself does not provide immunity to atherosclerosis8. Silent ischaemia in the general population is estimated in middle aged men to be approximately five per cent with an annual mortality of between one to three per cent9'10. The rate of asymptomatic atherosclerotic heart disease in highly trained athletes is unknown, but would be expected to be below five per cent. Droste and Roskamm found that asymptomatic patients had a much higher pain threshold than their symptomatic counterparts". This is consistent with a high pain threshold in highly trained athletes and, with a well developed coronary collateral system, may explain why 50 per cent of sudden deaths in vigorous exercise occur in runners who are previously asymptomatic. Sudden death during exercise may be unavoidable, but its incidence can be reduced by giving our proper information, especially to elderly runners. Any discomfort four weeks before a marathon race (or other vigorous programmes) should lead to medical examination. Furthermore, runners with a known family history of arteriosclerotic heart disease should be referred for a medical examination including ECG, treadmill test, and blood lipids.

Two questionnaires were given to the participants of the Danish national marathon championship to obtain information on health, training habits, previous injuries and the medical problems sustained during and after the competition. All 60 participants replied to both questionnaires. The elite runner is training between 90-150 km per week, using one daily training session. He is generally careful about stretching and warming up and down. Forty-three per cent of runners sustained injuries in the last year that prevented them from training, but only 3% needed to stay off work. The most common reasons for not completing the race were exhaustion and injuries to the lower extremities. Sixty-one per cent of the runners who did not drink at all refreshment stations dropped out, whereas only 27% of those who did dropped out. There was no difference in relation to results or medical problems between the group who used a special diet before the run and those who did not. The major medical problems were gastrointestinal disturbances, skin lesions and pain or cramps in the lower extremities. No serious injuries were reported.

To determine the air concentrations of methylmethacrylate monomer and thus obtain information about the safety in the operating theater, a methylmethacrylate Dräger tube was used in connection with a bellows pump. This method gives an instantly readable value correlated with more complicated gas chromatographic measurements.

Based on a study of the literature and our own experience treating fisherman poisoned by mustard gas, this article outlines the clinical effects, and toxicological and mutagenic properties of the agent. Mustards are very persistent chemical agents that easily penetrate clothing. Mustard gas usually causes clinical symptoms after the liquid penetrates the skin or the vapor is inhaled. Skin lesions are similar to first- or second-degree burns and usually heal spontaneously in 4 to 6 weeks. Eye symptoms are photophobia and reduced vision. Following inhalation of the agent, pulmonary edema and long-term dyspnea may be seen. As mustard gas is an alkylating substance, it is conceivable that the risk of developing cancer may be increased, as observed in people who were involved with the production of mustard gas and in animals exposed to the gas. Also, transient significantly increased sister chromatid exchange rates have been found in fishermen exposed to mustard gas. Patients exposed to mustard gas must be treated immediately after exposure. Treatment should consist of cleaning of the exposed skin and clothes with an antigas powder and water and soap. The skin lesions should be treated as burns. Eye lesions and respiratory problems should be treated symptomatically.

Ordinary surgical rubber gloves are penetrated by methylmethacrylate monomer (MMA) in less than 1 minute, as demonstrated by gas chromatographic measurements. A three-layered PVP glove, 0.07 mm thick--consisting of an outer layer of polyethylene, an intermediary layer of ethylene vinyl alcohol copolymer, and an inner layer of polyethylene--was impervious for 20 minutes, whereas a viton-butyl rubber glove, 0.27 mm thick, was impervious for 15 minutes. The PVP glove is recommended to orthopedic surgeons, nurses, and other handling acrylic bone cements to avoid sensitization, and is especially recommended to persons with known contact allergy to MMA.

2 cases of contact dermatitis to methyl methacrylate monomer are presented. The patients are nurses who mixed bone cement at orthopedic operations. During the procedure, they used 2 pairs of gloves (latex). Butyl rubber gloves are recommended for methyl methacrylate monomer to avoid sensitization and/or cumulative irritant contact dermatitis on the hands.