ArticlesStillbirths among offspring of male radiation workers at Sellafield nuclear reprocessing plant
Introduction
There has been concern about possible transgenerational effects of exposure to ionising radiation since the earliest days of radiobiological research. Exposure of male mammals to preconceptional ionising radiation causes a range of adverse outcomes in their offspring, including death, cancer, and congenital anomaly.1, 2, 3, 4, 5 In 1988 a UK government committee6 investigating the excess risk of leukaemia in children in the vicinity of the Dounreay nuclear-fuel reprocessing plant in the north of Scotland recommended that “epidemiological studies should be set up to consider any possible effects on the health of the offspring of parents occupationally exposed to radiation”. This concern received further emphasis in 1990 when Gardner and colleagues7 reported the results of a case-control study of young people diagnosed with leukaemia and lymphoma in west Cumbria, UK, concluding that the substantial excess of these malignant disorders in young people in Sellafield could be the result of their fathers' preconceptional radiation exposure while employed at Sellafield, the adjacent nuclear-fuel reprocessing plant, with exposure during the period immediately before conception being particularly important. However, the hypothesis that paternal preconceptional irradiation is causally associated with childhood leukaemia and lymphoma has not been supported by further epidemiological investigations.8, 9, 10, 11
Any transgenerational effects of paternal preconceptional irradiation would be likely to appear as outcomes such as congenital anomalies rather than childhood leukaemia since these have a much higher heritable component.12 The Sellafield workforce is of particular interest because of its comparatively high exposures to ionising radiation.13 The current programme of work set out to study transgenerational effects of paternal preconceptional irradiation in the offspring of this workforce, by investigating the association of such irradiation with the sex ratio and adverse health outcome in their children (stillbirth, infant death, cancer).8, 14, 15, 16 The present study investigated whether there was evidence of increasing risk of stillbirth (including those with congenital anomaly), within the cohort of children born to male radiation workers at the Sellafield site, with increasing external or internal preconceptional exposure to ionising radiation during either the 90 days immediately before conception (ie, during the period of spermatogenesis), or the entire preconceptional period of employment within the nuclear industry.
Section snippets
Participants
A cohort study was done of all singleton births from 1950 to 1989 to fathers employed at Sellafield while resident in the county of Cumbria. Preconceptional radiation doses were estimated from annual external dose summaries and from routine internal dose assessments. Doses in the 90 days before conception were estimated pro rata from annual dose summaries. Investigation of the relation between paternal preconceptional irradiation and stillbirth by specific cause was possible only from 1961
Non-Sellafield cohort
The distribution of births by decade, social class, and birth order is shown in table 1. Sex was not a significant risk factor for stillbirth. The best fit for the change in stillbirth rate by year of birth was a cubic model, adjusted for social class and birth order (Pearson χ21022=1005, p=0·64). The model predicted 99·9 stillbirths (96 observed) among children conceived by fathers who were subsequently employed at Sellafield and 18·1 stillbirths (21 observed) in children of non-radiation
Discussion
Stillbirth risk was significantly associated with total external paternal preconceptional irradiation in both the cohort and case-control studies. The risk was higher for stillborn babies with congenital anomalies, in particular those with neural-tube defects. In the cohort study there was also a significant association with ASD90, but no association was found with FB90 in the case-control study, suggesting that this may have been an artefact caused by the use of pro-rata 90-day dose estimates
References (39)
- et al.
Ionizing radiation and genetic risks—VIII: the concept of mutation component and its use in risk estimation for multifactorial diseases
Mutat Res
(1998) - et al.
Induction of congenital anomalies in the offspring of male mice treated with X-rays at pre-meiotic and post-meiotic stages
Mutat Res
(1984) Scientific committee on the effects of atomic radiation UNSCEAR 1993 report of the general assembly, with scientific annexes: sources and effects of ionizing radiation
(1993)Scientific committee on the effects of atomic radiation UNSCEAR 1994 report of the general assembly, with scientific annexes: sources and effects of ionizing radiation
(1994)- et al.
Tumour induction by methyl-nitroso-urea following preconceptional paternal contamination with plutonium-239
Br J Cancer
(1998) - et al.
Investigation of lung tumour induction in BALB/cJ mice following paternal irradiation
Int J Radiat Biol
(1995) - et al.
Effect of pre-conceptional external or internal irradiation of N5 male mice and the risk of leukaemia in their offspring
Carcinogenesis
(1998) Committee on medical aspects of radiation in the environment (COMARE) second report: investigation of the possible increased incidence of leukaemia in young people near the Dounreay nuclear establishment, Caithness, Scotland
(1988)- et al.
Results of case-control study of leukaemia and lymphoma among young people near Sellafield nuclear plant in West Cumbria
BMJ
(1990) - et al.
Geographical distribution of preconceptional radiation doses to fathers employed at the Sellafield nuclear installation, West Cumbria
BMJ
(1993)
Paternal exposure not to blame
Nature
Committee on medical aspects of radiation in the environment (COMARE) fourth report: the incidence of cancer and leukaemia in young people in the vicinity of the Sellafield site, West Cumbria—further studies and an update of the situation since the publication of the report of the Black Advisory Group in 1984
Cancer in the offspring of radiation workers: a record linkage study
BMJ
The descriptive statistics and health implications of occupational radiation doses received by men at Sellafield nuclear installation before the conception of their children
J Radiol Protect
Direct estimates of cancer mortality due to low doses of ionising radiation: an international study
Lancet
The sex ratio of children in relation to paternal preconceptional radiation dose: a study in Cumbria, northern England
J Epidemiol Commun Health
The creation of a database of children of workers at a nuclear facility—an exercise in record linkage
Appl Occupat Environ Hygiene
Stillbirth rates around the nuclear installation at Sellafield north west England: 1950–89
Int J Epidemiol
Standard occupation classification, volumes 1, 2, and 3
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