Epidemiology and the planned new Data Protection Directive of the European Union: a symposium report.

A revision of the 1995 Data Protection Directive of the European Union is currently in preparation. It is argued that the revised version should take explicitly and adequately into account the special requirements for personal data collection, storage and use needed in epidemiological research activities such as health services auditing, studies involving disease registries and investigations of public health emergencies.

IGF-I, IGFBP-3 and breast cancer risk in women: The European Prospective Investigation into Cancer and Nutrition (EPIC).

Blood concentrations of insulin-like growth factor-I (IGF-I) and insulin-like growth factor binding protein-3 (IGFBP-3) have recently been associated with breast cancer risk, notably in women who developed breast cancer at a young age. Prospective studies published so far, however, were relatively small and odds ratio (OR) estimates imprecise. We present the results of a large prospective case-control study nested within the European Prospective Investigation into Cancer and Nutrition on total IGF-I, IGFBP-3 and breast cancer risk including 1081 incident cases of invasive breast cancer and 2098 matched control subjects. Increasing IGF-I and IGFBP-3 concentrations were associated with a significant increase in breast cancer risk in women who developed breast cancer after 50 years of age (highest vs lowest quintile OR 1.38 (95% confidence interval (CI) 1.02-1.86), P = 0.01, and 1.44 (95% CI 1.04-1.98), P = 0.01, respectively), but no relationship was observed in younger women (OR = 1.03 (95% CI 0.60-1.77), P = 0.81 for IGF-I, and OR = 0.92 (95% CI 0.50-1.70), P = 0.69 for IGFBP-3). There was, however, significant heterogeneity in the relationship of breast cancer with serum IGF-I and IGFBP-3 levels depending on the time interval between blood donation and tumor diagnosis. A reduction in breast cancer risk with increasing IGF-I concentrations was observed in cases with a diagnosis of cancer less than 2 years after blood donation, (OR = 0.76 (95% CI 0.57-1.03)), while an increase in risk was observed for women with a later diagnosis (above or equal to two years after blood collection, OR = 1.51 (95% CI 1.19-1.91)). A similar pattern was observed for IGFBP-3. This study confirms previous findings for an association of serum IGF-I and IGFBP-3 concentrations with breast cancer risk, particularly for women with a later diagnosis of cancer, but it does not support the hypothesis of an involvement of IGF-I in younger women.

Time trends of primary liver cancer: indication of increased incidence in selected cancer registry populations.

Primary liver cancer (PLC) data from 30 selected cancer registries covering 37 populations in 18 countries were used to compare incidence rates in two periods (2-5 yr long) between 1956 and 1972. The median distance between central years of the two periods was about 8 years. Over this interval, all-ages incidence rates, standardized to world population, showed a statistically significant increase in 17 (45.9%) of the populations for males and in 10 (27.0%) for females. Corresponding figures for the 0- to 44-year age group were 4 (10.8%) for males and 7 (18.9%) for females. One statistically significant decrease was observed among the remaining populations. Over the whole set of 37 populations the median percent yearly increase was +3.7 for males and +6.7 for females (all ages) and +1.3 for males and +8.3 for females (ages 0-44 yr). The increase in PLC was most clearly identifiable in the populations of Kracow, Poland; Alberta, Canada; and Bombay, India; and in the Jewish population of Israel. Correlations between levels and/or changes of some variables (per capita income and calorie and alcohol consumption) and changes in PLC rates provided no consistent pattern of results. Changes in PLC mortality rates showed only a weak correlation with changes in PLC incidence rates, indicating the inadequacy of mortality data to describe PLC trends. Data on PLC incidence trends, as available from routine source, appeared insufficient to determine the role of diagnosis-registration changes in the observed increase and to exclude the contribution of etiologic factors.

Multicenter case-control study of exposure to environmental tobacco smoke and lung cancer in Europe.

BACKGROUND: An association between exposure to environmental tobacco smoke (ETS) and lung cancer risk has been suggested. To evaluate this possible association better, researchers need more precise estimates of risk, the relative contribution of different sources of ETS, and the effect of ETS exposure on different histologic types of lung cancer. To address these issues, we have conducted a case-control study of lung cancer and exposure to ETS in 12 centers from seven European countries. METHODS: A total of 650 patients with lung cancer and 1542 control subjects up to 74 years of age were interviewed about exposure to ETS. Neither case subjects nor control subjects had smoked more than 400 cigarettes in their lifetime. RESULTS: ETS exposure during childhood was not associated with an increased risk of lung cancer (odds ratio [OR] for ever exposure = 0.78; 95% confidence interval [CI] = 0.64-0.96). The OR for ever exposure to spousal ETS was 1.16 (95% CI = 0.93-1.44). No clear dose-response relationship could be demonstrated for cumulative spousal ETS exposure. The OR for ever exposure to workplace ETS was 1.17 (95% CI = 0.94-1.45), with possible evidence of increasing risk for increasing duration of exposure. No increase in risk was detected in subjects whose exposure to spousal or workplace ETS ended more than 15 years earlier. Ever exposure to ETS from other sources was not associated with lung cancer risk. Risks from combined exposure to spousal and workplace ETS were higher for squamous cell carcinoma and small-cell carcinoma than for adenocarcinoma, but the differences were not statistically significant. CONCLUSIONS: Our results indicate no association between childhood exposure to ETS and lung cancer risk. We did find weak evidence of a dose-response relationship between risk of lung cancer and exposure to spousal and workplace ETS. There was no detectable risk after cessation of exposure.

Target organs for carcinogenicity of chemicals and industrial exposures in humans: a review of results in the IARC monographs on the evaluation of the carcinogenic risk of chemicals to humans.

Epidemiological observations indicate that cancers affecting different organs and systems in humans have different causes. At the descriptive level, cancer incidence and mortality rates exhibit patterns of geographic and temporal variation which are distinct and separate for each cancer site and even, at a given site, for different histological types (for instance, increasing squamous cell carcinoma of the lung and decreasing stomach cancer in most developed countries in recent decades). The existence of these distinct patterns in itself indicates that different causes are at the origin of cancers at different sites. Hence, it is of scientific and practical importance not only to identify agents that are carcinogenic to humans but also to specify as definitely as possible the target organ(s) of their action. This is done in the present review of results in the International Agency for Research on Cancer Monographs on the Evaluation of the Carcinogenic Risk of Chemicals to Humans.

Evaluation of the carcinogenicity of chemicals: a review of the Monograph Program of the International Agency for Research on Cancer (1971 to 1977).

In 1971 the International Agency for Research on Cancer initiated a program on the evaluation of the carcinogenic risk of chemicals to humans, which concentrated on the production of monographs on individual chemicals. A review of this ongoing program is presented here as a contribution to the discussion of primary prevention of cancer. A total of 368 chemicals were evaluated in the first 16 volumes of the International Agency for Research on Cancer monographs. For 26 chemicals (or industrial processes), a positive association between exposure and the occurrence of cancer in humans was observed. For 221 chemicals, some evidence of carcinogenicity was found in at least one species of experimental animals. However, no evaluation of the carcinogenic risk of these chemicals to humans was made, either because no epidemiological studies or case reports were available or because the results of available human studies were inconclusive. For the remaining 121 chemicals, the available data were inadequate for an evaluation of the presence or absence of a carcinogenic effect in experimental animals or humans. The criteria on which the carcinogenicity of chemicals to humans and/or experimental animals was assessed, from the initiation of this program in 1971 until 1977, have recently been revised and are briefly discussed.

Postmenopausal serum androgens, oestrogens and breast cancer risk: the European prospective investigation into cancer and nutrition.

Considerable experimental and epidemiological evidence suggests that elevated endogenous sex steroids - notably androgens and oestrogens - promote breast tumour development. In spite of this evidence, postmenopausal androgen replacement therapy with dehydroepiandrosterone (DHEA) or testosterone has been advocated for the prevention of osteoporosis and improved sexual well-being. We have conducted a case-control study nested within the European Prospective Investigation into Cancer and Nutrition. Levels of DHEA sulphate (DHEAS), (Delta4-androstenedione), testosterone, oestrone, oestradiol and sex-hormone binding globulin (SHBG) were measured in prediagnostic serum samples of 677 postmenopausal women who subsequently developed breast cancer and 1309 matched control subjects. Levels of free testosterone and free oestradiol were calculated from absolute concentrations of testosterone, oestradiol and SHBG. Logistic regression models were used to estimate relative risks of breast cancer by quintiles of hormone concentrations. For all sex steroids -the androgens as well as the oestrogens - elevated serum levels were positively associated with breast cancer risk, while SHBG levels were inversely related to risk. For the androgens, relative risk estimates (95% confidence intervals) between the top and bottom quintiles of the exposure distribution were: DHEAS 1.69 (1.23-2.33), androstenedione 1.94 (1.40-2.69), testosterone 1.85 (1.33-2.57) and free testosterone 2.50 (1.76-3.55). For the oestrogens, relative risk estimates were: oestrone 2.07 (1.42-3.02), oestradiol 2.28 (1.61-3.23) and free oestradiol (odds ratios 2.13 (1.52-2.98)). Adjustments for body mass index or other potential confounding factors did not substantially alter any of these relative risk estimates. Our results have shown that, among postmenopausal women, not only elevated serum oestrogens but also serum androgens are associated with increased breast cancer risk. Since DHEAS and androstenedione are largely of adrenal origin in postmenopausal women, our results indicated that elevated adrenal androgen synthesis is a risk factor for breast cancer. The results from this study caution against the use of DHEA(S), or other androgens, for postmenopausal androgen replacement therapy.

Do the nonsmoking daughters of smokers tend to marry smokers? Implications for epidemiological research on environmental tobacco smoke: the IARC collaborative study.

The IARC collaborative study on exposure to environmental tobacco smoke (ETS) involved collecting interview data and biochemical indicators of exposure from 1369 nonsmoking women in 13 centers in 10 countries. Information on childhood and adulthood exposure to other people's smoke and duration of this exposure from both parents and spouse was gathered at the interview. Of the 900 women whose husbands smoked (current or exsmokers), 71.3% had one or both parents who smoked (predominantly the father), whereas among the 277 women married to never-smokers, only 60.3% had at least one parent who smoked. The odds ratio for the daughter of a smoker to marry a smoker was, therefore, 1.64 (95% confidence interval = 1.24-2.17; P > 0.001), and there was an exposure-response relation between the number of years of childhood exposure to ETS from the parents and the likelihood of being married to a smoker. These results show that nonsmoking women married to smokers are more likely to have been exposed to tobacco pollution during their whole life. Because the duration of exposure is known to be important in the genesis of lung cancer, some of the excess risk of lung cancer in nonsmoking women married to smokers may be due exposure to ETS from parents during childhood.

Environmental tobacco smoke and the risk of cancer in adults.

The apparent effect of environmental tobacco smoke (ETS) exposure on cancer risk has become an important social and political issue. The risk of cancer in non-smokers is often the main reason for prohibiting or restricting smoking in public places. A number of epidemiological studies have shown an association between ETS exposure and lung cancer. However, the strength of this association has still to be estimated. Only a few studies have reported on ETS and cancer from sites other than the lung in adults. No definite conclusions can be drawn at present from a critical review of the epidemiological evidence, but the suggestion of an association is present for sinonasal cancer, while bladder cancer does not seem to be associated to ETS exposure. Positive studies are available for cancers from other sites, including the breast, the uterine cervix and the brain, but these are difficult to interpret.

Long-term hazards of polychlorinated dibenzodioxins and polychlorinated dibenzofurans.

During January 10-11, 1978 in Lyon, France, a joint National Institute of Environmental Health Sciences/International Agency for Research on Cancer ad hoc Working Group considered and discussed the feasibility of coordinating epidemiological studies on the long-term hazards associated with the chlorinated dibenzo-p-dioxins and chlorinated dibenzofurans (PCDDs and and PCDFs). Nineteen invited scientists from eight countries presented introductory working papers summarizing the most up-to-date and relevant information available from their individual programs. This report represents the collective views and scientific opinions of the Working Group. The greater part of this document comprises epidemiological studies related to episodes of human exposures. The review begins with a brief section concerning possible routes of human exposure, an overview of the pertinent chemical characteristics, and the salient toxicological properties of the structurally similar PCDDs/PCDFs. The Working Group report ends with recommendations for future activities.

Carcinogen metabolism in human lung tissues and the effect of tobacco smoking: results from a case--control multicenter study on lung cancer patients.

Cigarette smoking is the strongest risk factor for lung cancer, but genetically determined variations in the activities of pulmonary enzyme that metabolize tobacco-derived carcinogens may affect individual risk. To investigate whether these enzymes (e.g., CYP1A-related) can serve as markers for carcinogen-DNA damage, lung tissue specimens were taken during surgery from middle-aged men with either lung cancer or non-neoplastic lung disease. Phase I [aryl hydrocarbon hydroxylase (AHH), ethoxycoumarin O-deethylase (ECOD)] and phase II (epoxide hydrolase, UDP-glucuronosyltransferase, glutathione S-transferase) enzyme activities, glutathione and malondialdehyde contents were determined in lung parenchyma and/or bronchial tissues; some samples were also analyzed for DNA adducts, using 32P-postlabeling. The data were then analyzed for the following: a) differences in metabolic profiles between bronchial and parenchymal lung tissue; b) the effect of recent exposure to tobacco smoke on enzyme inducibility and benzo[a]pyrene metabolism; c) differences in enzyme inducibility between lung cancer and non-lung cancer patients; d) the effect of smoking on metabolism of mutagens in vitro; e) pulmonary DNA adduct levels and AHH activity in lung parenchyma of smokers and ex-smokers; f) lipid peroxidation products in lung tissue from lung cancer and non-lung cancer patients, as related to smoking habits and degree of airway obstruction; and g) prognostic value of AHH pulmonary activity in lung cancer patients. The results demonstrate a pronounced effect of tobacco smoke on pulmonary metabolism of xenobiotics and prooxidant state and suggest the existence of a metabolic phenotype at higher risk for tobacco-associated lung cancer.

Exposure to dioxin and nonneoplastic mortality in the expanded IARC international cohort study of phenoxy herbicide and chlorophenol production workers and sprayers.

The authors studied noncancer mortality among phenoxyacid herbicide and chlorophenol production workers and sprayers included in an international study comprising 36 cohorts from 12 countries followed from 1939 to 1992. Exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin or higher chlorinated dioxins (TCDD/HCD) was discerned from job records and company questionnaires with validation by biologic and environmental measures. Standard mortality ratio analyses suggested a moderate healthy worker effect for all circulatory diseases, especially ischemic heart disease, among both those exposed and those not exposed to TCDD/HCD. In Poisson regression analyses, exposure to TCDD/HCD was not associated with increased mortality from cerebrovascular disease. However, an increased risk for circulatory disease, especially ischemic heart disease (rate ratio [RR] 1.67, 95% confidence interval [Cl] 1.23-2.26) and possibly diabetes (RR 2.25, 95% Cl 0.53-9.50), was present among TCDD/HCD-exposed workers. Risks tended to be higher 10 to 19 years after first exposure and for those exposed for a duration of 10 to 19 years. Mortality from suicide was comparable to that for the general population for all workers exposed to herbicides or chlorophenols and was associated with short latency and duration of exposure. More refined investigations of the ischemic heart disease and TCDD/HCD exposure association are warranted.

Pulmonary lipid peroxidation in cigarette smokers and lung cancer patients.

Lipid peroxidation (LPO) was studied in lung tissues of patients with lung cancer (LC, n = 37) or nonlung cancer (NLC, n = 13) and its relationships with the smoking habits and the degree of airway obstruction were investigated. Specimens of peripheral lung parenchyma, free of tumor tissue, were taken and the malondialdehyde (MDA) content was measured in the S-12 fractions. Airway obstruction was assessed by flow-volume curves, and data were expressed as percentage of the predicted values. Cigarettes smoked were expressed as pack-years. The patients with LC and NLC did not differ by MDA content, age, and number of pack-years. On the contrary, FEF75-85 and MEF75 were significantly lower in LC than in NLC patients (p less than 0.05). The MDA content was inversely correlated to number of days patients had refrained from smoking (r = -0.66, p less than 0.001). The MDA content was higher in recent smokers (ie, people smoking during the last 30 days before surgery) than in the other patients (0.136 +/- 0.007 vs 0.116 +/- 0.007 mumol/g of tissue, p less than 0.05) and, by considering only recent smokers, MDA content was higher in LC patients (0.144 +/- 0.008 mumol/g of tissue) than in NLC patients (0.113 +/- 0.014 mmol/g tissue, p = 0.059). When patients were divided into "high MDA" and "low MDA" groups, MEF75 was much lower in the high MDA group (35.1 +/- 3.4 percent) than in the low MDA group (55.1 +/- 8.1 percent) (p less than 0.01). These results suggest the following: (1) enhanced level of prooxidant state in the lungs is associated with recent cigarette smoking; (2) LC patients may be more prone than respective NLC patients to oxidative stress; (3) MDA level and degree of small airway obstruction were associated and differed between LC and NLC patients even though these groups did not differ in the percentage of recent smokers; and (4) a common free-radical mediated pathway may be active for both LC and small airway obstruction.

Non-smoker lung cancer deaths attributable to exposure to spouse's environmental tobacco smoke.

BACKGROUND: The causal relationship between environmental tobacco smoke (ETS) and lung cancer is established; however, the magnitude of the risk is not known. Therefore, it is conceivable that ETS is responsible for a number of lung cancer deaths because of the large number of smokers and the widespread presence of ETS. We estimated the number of lung cancer deaths occurring in 1990 in the European Union (EU), attributable to ETS generated by a spouse. METHODS: In each country and for each sex, we used the proportion of smokers and of married people in 1970 to estimate the number of lung cancer deaths not attributable to tobacco smoking occurring in married people, assuming a relative risk (RR) for active smoking equal to 10. We then assumed a prevalence of smoking among these deaths equal to the population at large, and estimated the number of deaths attributable to ETS based on an RR for ETS of 1.3. Additional analyses were carried out assuming different values of RR for smoking and exposure to spouse's ETS. RESULTS: Based on our best assumptions, we calculated that 1146 (839 females, 307 males) lung cancer deaths were attributable to exposure to spouse's ETS in the EU in 1990. All the hypotheses tested resulted in not less than several hundred deaths. CONCLUSION: Regardless of the limitations of this exercise, our results suggest that exposure to spouse's ETS represents a relatively important public health problem in the EU.

Validity of urinary biomarkers of exposure to tobacco smoke following prolonged storage.

BACKGROUND: The utility of using biomarkers of smoking in epidemiological studies depends not only on the validity and precision of the laboratory procedure but often on the long-term stability of the analytes of interest in stored biological samples. METHODS: We retrieved urine samples collected in 1976-1977 from women included in a cohort study in Utrecht and for whom information on smoking status was available. Creatinine and thiocyanate were measured in 1976-1977 on fresh samples. Cotinine and creatinine were analysed in 1988 on urine stored at -20 degrees C. RESULTS: Measurements of creatinine more than 10 years apart showed a correlation of 0.95 and equal means. Cotinine measurements made in 1988 allowed a clear separation of smokers and non-smokers (sensitivity 92%, specificity 100%), suggesting that concentrations retained their discriminant value even after 10 years of storage. CONCLUSION: These results emphasize the possibilities offered by long-term storage, under proper conditions, of biological samples for subsequent determination of analytes which may emerge as the study progresses.

The Malmö Food Study: validity of two dietary assessment methods for measuring nutrient intake.

BACKGROUND: Nutritional epidemiology relies largely on dietary assessment methods for the estimation of the "exposure' variables which may be related to disease risk. METHODS: This paper describes a methodological study conducted in Malmö, Sweden, to compare nutrient intake--estimated by two alternative dietary assessment methods--with a reference method consisting of 18 days of weighed food records. The two candidate methods were an extensive food frequency questionnaire with portion size to be estimated from a booklet of 120 sets of photos (method A) and a method involving the combination of a shorter questionnaire and a two-week food record (method B). RESULTS: In absolute values, both methods overestimated nutrient intake by 20-40%, with method B closer to the reference for most nutrients. Both crude and energy-adjusted correlations between A-reference and B-reference were of the order of 0.50-0.60 for energy, energy-providing nutrients and most vitamins and minerals. Correlations were in the same range for most of the 14 fatty acids considered in the analyses. Protein intake, estimated from the analyses of urinary nitrogen on 6-8 repeated 24-hour urine collections per subject, was almost identical to the reference method values. Correlation between nitrogen-derived values and dietary measurement was 0.75. CONCLUSIONS: Overall, the study indicated that both methods A and B had good ranking validity compared to the reference and that in most cases the combined method (B) performed slightly better than the extensive food frequency method (A).

Comparison of information on occupation and lifestyle habits obtained from European man-made vitreous fibre production workers and their relatives.

BACKGROUND: Studies of the aetiology of fatal diseases often rely on data obtained from relatives, which can cause loss of precision and introduce bias. We assessed the quality of such information on demographics, occupation, smoking and alcohol habits. METHODS: We compared contemporary interviews, based on a structured questionnaire, with male workers from the man-made vitreous fibre production industry in four European countries and their relatives. The participation rate was 63% (74 pairs of workers and relatives). RESULTS: Only minor differences in the ability to answer the questions appeared among workers and relatives, except for specific occupational questions. There was moderate to excellent agreement for demographics, residential and work history (kappa or intraclass correlation range: 0.44-0.98). For smoking habits, beer and wine consumption the agreement was good to excellent (range: 0.59-0.99). In particular, number of different residential areas, jobs, industries, and duration of wine drinking were significantly underreported by the relatives. No general determinant for reduced agreement appeared. CONCLUSIONS: In general, the quality of information obtained from relatives appeared good. However, information on specific occupational exposures may be improved by supplementing the information from relatives with details obtained from colleagues, occupational hygiene experts or occupation-exposure matrices.

The Malmö Food Study: the reproducibility of a novel diet history method and an extensive food frequency questionnaire.

OBJECTIVE: To assess the reproducibility of two diet assessment methods, an extensive quantitative food frequency questionnaire (method A) and a novel shorter quantitative food frequency questionnaire with a 14 day food record (method B). DESIGN: A randomized prospective cohort study. SETTING: General community. SUBJECTS: 241 residents of the town of Malmö, aged between 50-69 years, 126 men and 115 women who completed the methods one year apart. METHODS: Both diet methods were designed to cover the whole diet and portion sizes were estimated using a booklet with 120 photographs; method A comprised 250 items and method B combined a two-week food record measuring lunch and dinner meals and a shorter 130 item quantitative food frequency questionnaire for average consumption of foods, snacks and beverages during the past year; RESULTS: The percent difference between estimated energy intake one year apart were for men 10.7% for method A and 0.2% for method B, corresponding values for women 13.7% and 1.1%. Method B showed a good agreement between measurements for energy-providing nutrients, micronutrients and major food groups, i.e. meat products, edible fats, milk, fish, fruits and vegetables with correlation coefficients between 0.70-0.90 for women. The percent difference of average intake of edible fat was about 10%. Average energy-adjusted Pearson's correlation coefficients were of the order of 0.50-0.80 for most nutrients including 14 fatty acids. The correlation for the ratio between polyunsaturated and saturated fatty acids were about 0.70 for men and 0.80 for women; CONCLUSION: A modified diet history method combining a food record and a food frequency questionnaire shows good reproducibility.

The Malmö Food Study: the relative validity of a modified diet history method and an extensive food frequency questionnaire for measuring food intake.

OBJECTIVE: To assess the relative validity of two diet assessment methods, an extensive quantitative food frequency questionnaire (method A) and a novel shorter quantitative food frequency questionnaire with a 14 day food record (method B). DESIGN: A randomized prospective cohort study. SETTING: General community. SUBJECTS: 206 residents of the town of Malmö, aged between 50-69 years, 101 men and 105 women who completed the methods during one year. METHODS: Both diet methods were designed to cover the whole diet and portion sizes were estimated using a booklet with 120 photographs; method A comprised 250 items and method B combined a two-week food record measuring lunch and dinner meals and a shorter 130 item quantitative food frequency questionnaire for average consumption of foods, snacks and beverages during the past year. An 18 day dietary record comprising six 3-day weighed records evenly distributed over one year served as a reference method. RESULTS: Pearson's correlation coefficients varied from 0.25 for fat intake to 0.84 for milk products for method A and from 0.32 for fish to 0.88 for meat for method B. Correlations for most food groups ranged between 0.50-0.80, and were higher for method B. Only small changes were noted after adjustment for energy intake. On average for most food groups categorization of subjects into quartiles, 55% of subjects belonging to the lowest quartile, and 57-59% of those belonging to the highest quartile for method A and B were correctly classified. CONCLUSION: A combined food record with a quantitative food frequency questionnaire is a better tool for food assessment than an extensive food frequency questionnaire.

Should euthanasia be legal? An international survey of neonatal intensive care units staff.

OBJECTIVE: To present the views of a representative sample of neonatal doctors and nurses in 10 European countries on the moral acceptability of active euthanasia and its legal regulation. DESIGN: A total of 142 neonatal intensive care units were recruited by census (in the Netherlands, Sweden, Hungary, and the Baltic countries) or random sampling (in France, Germany, Italy, Spain, and the United Kingdom); 1391 doctors and 3410 nurses completed an anonymous questionnaire (response rates 89% and 86% respectively). MAIN OUTCOME MEASURE: The staff opinion that the law in their country should be changed to allow active euthanasia "more than now". RESULTS: Active euthanasia appeared to be both acceptable and practiced in the Netherlands, France, and to a lesser extent Lithuania, and less acceptable in Sweden, Hungary, Italy, and Spain. More then half (53%) of the doctors in the Netherlands, but only a quarter (24%) in France felt that the law should be changed to allow active euthanasia "more than now". For 40% of French doctors, end of life issues should not be regulated by law. Being male, regular involvement in research, less than six years professional experience, and having ever participated in a decision of active euthanasia were positively associated with an opinion favouring relaxation of legal constraints. Having had children, religiousness, and believing in the absolute value of human life showed a negative association. Nurses were slightly more likely to consider active euthanasia acceptable in selected circumstances, and to feel that the law should be changed to allow it more than now. CONCLUSIONS: Opinions of health professionals vary widely between countries, and, even where neonatal euthanasia is already practiced, do not uniformly support its legalisation.