Stillbirths among offspring of male radiation workers

Abstract

The radiation workers in Louise Parker and colleagues' study1Parker L Pearce MS Dickinson HO et al.Stillbirths among the offspring of male radiation workers at the Sellafield nuclear reprocessing plant.Lancet. 1999; 354: 1407-1414Summary Full Text Full Text PDF PubMed Scopus (92) Google Scholar had total cumulative external preconceptional doses in the range 0·01–911 mSv with a median of 30·1 mSv. Of the 9208 births to the partners of these men, 130 were stillborn and the statistical models derived by the researchers predict that up to 31·9 of these might be attributable to the radiation exposure received by the fathers. By contrast, studies on the offspring of the Japanese atomic bomb survivors have failed to find any significant association with parental radiation exposure for a range of adverse pregnancy outcomes and other measures of possible genetic effects.2Neel JV Schull WJ The children of Atomic bomb survivors. Natl Acad Press, Washington DC1991Google Scholar In the atomic bomb studies, stillbirths alone, with maternal age and parity taken into account, were analysed and no association with paternal dose was shown. Studies of somatic mutations in Sellafield workers, who received low dose chronic exposure, consistently indicate lower yields in comparison with similar studies on the actuely exposed Japanese atomic bomb survivors.3Tucker JD Tawn EJ Holdsworth D et al.Biological dosimetry of radiation wokers at the Sellafield nuclear facility.Radiat Res. 1997; 148: 216-226Crossref PubMed Scopus (90) Google Scholar, 4Cole J Arlett CF Green MHL et al.Mutant frequencies in workers at the Sellafield installation.Health Phys. 1995; 68: 388-393Crossref PubMed Scopus (15) Google Scholar Chromosome analysis of peripheral blood lymphocytes for stable aberrations revealed frequencies per unit dose a factor of six lower than those seen in atomic bomb survivors.3Tucker JD Tawn EJ Holdsworth D et al.Biological dosimetry of radiation wokers at the Sellafield nuclear facility.Radiat Res. 1997; 148: 216-226Crossref PubMed Scopus (90) Google Scholar Studies of mutations in hypoxanthine-guanine phosphoribosyltransferase and glycophorin A have shown no significant increases in the Sellafield workers3Tucker JD Tawn EJ Holdsworth D et al.Biological dosimetry of radiation wokers at the Sellafield nuclear facility.Radiat Res. 1997; 148: 216-226Crossref PubMed Scopus (90) Google Scholar, 4Cole J Arlett CF Green MHL et al.Mutant frequencies in workers at the Sellafield installation.Health Phys. 1995; 68: 388-393Crossref PubMed Scopus (15) Google Scholar in contrast with the raised frequencies seen in those exposed to radiation from the atomic bombs. Also, animal studies have established a reduction in effect for chronic exposure on gonadal cells, which indicates that the genetic effect of chronic exposure to spermatogonia is about a third that induced by acute irradiation.5United Nations scientific committee on the effects of atomic radiation, sources and effects of ionising radiation (UNSCEAR 1993 Report). New York: United Nations: 1993.Google Scholar Thus, whether the statistical association found by Parker and colleagues represents a real biological effect is doubtful.