Incidence of leukaemia and other cancers in birth and schools cohorts in the Dounreay area.

OBJECTIVE: To determine whether a raised incidence of leukaemia in the Dounreay area occurred in children born to local mothers (birth cohort) or in those who moved to the area after birth (schools cohort) and also whether any cases of cancer have occurred in children born near Dounreay who may have moved elsewhere. DESIGN: Follow up study. SETTING: Dounreay area of Caithness, Scotland. SUBJECTS: 4144 children born in the area in the period 1969-88 and 1641 children who attended local schools in the same period but who had been born elsewhere. MAIN OUTCOME MEASURES: Cancer registration records linked to birth and school records with computerised probability matching methods. RESULTS: Five cancer registrations were traced from the birth cohort compared with 5.8 expected on the basis of national rates (observed to expected ratio 0.9, 95% confidence interval 0.3 to 2.0). All five cases were of leukaemia (2.3, 0.7 to 5.4). In the schools cohort three cases were found (2.1, 0.4 to 6.2), all of which were of leukaemia (6.7, 1.4 to 19.5). All eight children were resident in the Dounreay area at the time of diagnosis; thus no cases were found in children who were born in or had attended school in the study area but who subsequently moved away. CONCLUSION: The raised incidence of leukaemia in both the birth and schools cohorts suggests that place of birth is not a more important factor than place of residence in the series of cases of leukaemia observed near Dounreay area.

Case-control study of leukaemia and non-Hodgkin's lymphoma in children in Caithness near the Dounreay nuclear installation.

OBJECTIVE: To examine whether the observed excess of childhood leukaemia and non-Hodgkin's lymphoma in the area around the Dounreay nuclear installation is associated with established risk factors, or with factors related to the plant, or with parental occupation in the nuclear industry. DESIGN: Case-control study. SETTING: Caithness local government district. SUBJECTS: 14 cases of leukaemia and non-Hodgkin's lymphoma occurring in children aged under 15 years diagnosed in the area between 1970 and 1986 and 55 controls matched for sex, date of birth, and area of residence within Caithness at time of birth. MAIN OUTCOME MEASURES: Antenatal abdominal x ray examination; drugs taken and viral infections during pregnancy; father's occupation; father's employment at Dounreay and radiation dose; distance of usual residence from the path of microwave beams, preconceptional exposure to non-ionising radiation in the father; and other lifestyle factors. RESULTS: No raised relative risks were found for prenatal exposure to x rays, social class of parents, employment at Dounreay before conception or diagnosis, father's dose of ionising radiation before conception, or child's residence within 50 m of the path of microwave transmission beams. Results also proved negative for all lifestyle factors except an apparent association with use of beaches within 25 km of Dounreay. However, this result was based on small numbers, arose in the context of multiple hypothesis testing, and is certainly vulnerable to possible systematic bias. CONCLUSION: The raised incidence of childhood leukaemia and non-Hodgkin's lymphoma around Dounreay cannot be explained by paternal occupation at Dounreay or by paternal exposure to external ionising radiation before conception. The observation of an apparent association between the use of beaches around Dounreay and the development of childhood leukaemia and non-Hodgkin's lymphoma might be an artefact of multiple testing and influenced by recall bias.

Proximity of the home to a cooling tower and risk of non-outbreak Legionnaires' disease.

OBJECTIVE: To study the source of non-outbreak legionnaires' disease, particularly the role of cooling towers, by comparing the locations of patients' homes in relation to the location of cooling towers. DESIGN: Retrospective, descriptive study of a case series of patients with legionnaires' disease ill between 1978 and 1986 and, for comparison, a case series of patients with lung cancer. A prospectively developed register and interview based survey provided data on the location of cooling towers. SETTING: The city of Glasgow. PATIENTS: 134 patients aged 14-84 with legionnaires' disease during 1978-86 and 10,159 patients with lung cancer during the same period. MAIN OUTCOME MEASURES: The locations of patients' homes and cooling towers as defined by postcodes, which provided map grid references accurate to 10 m; numbers of expected and observed cases of legionnaires' disease in census enumeration districts; and distance of enumeration districts from the nearest cooling tower as defined by five distance categories. RESULTS: Most cooling towers were in or near the city centre or close to the River Clyde, as were the places of residence of patients with community acquired, non-travel, non-outbreak legionnaires' disease (n = 107). There was an inverse association between the distance of residence from any cooling tower and the risk of infection, the population living within 0.5 km of any tower having a relative risk of infection over three times that of people living more than 1 km away. There was no such association with respect to travel related legionnaires' disease, and for lung cancer the association was weak (relative risk less than or equal to 1.2 in any distance group). CONCLUSION: In Glasgow cooling towers have been a source of infection in two outbreaks of legionnaires' disease and, apparently, a source of non-outbreak infection also. Better maintenance of cooling towers should help prevent non-outbreak cases. This method of inquiry should be applied elsewhere to study the source of this and other environmentally acquired disease.

Early emergency care study: the potential and benefits of advanced prehospital care.

Of 26358 patients taken by ambulance to the accident and emergency departments of two large hospitals, 1185 were admitted to resuscitation areas. The scope for ambulance staff to employ a range of advanced techniques at the scene of incidents was assessed by using information relating to the condition of patients when they were picked up by the ambulance and on admission, time in transit, details from hospital records, and outcome at three months. For non-survivors further assessment was made of the benefit, in terms of survival, which might have accrued had advanced techniques been used. The results of the assessment of benefit were compared with estimates of benefit from other studies. In cases of cardiopulmonary arrest the potential to save lives was less optimistic than earlier estimates, and in cases of trauma the potential to save lives was negligible.