Evaluation of Internal Alpha-Particle Radiation Exposure and Subsequent Fertility among a Cohort of Women Formerly Employed in the Radium Dial Industry

Abstract

This study examined the effect of internal exposure to alpha-particle radiation on subsequent fertility among women employed in the radium dial industry prior to 1930, when appreciable amounts of radium were often ingested through the practice of pointing the paint brush with the lips. The analysis was limited to women for whom a radium body burden measurement had been obtained and who were married prior to age 45 (n = 603). Internal radiation dose to the ovary was calculated based on initial intakes of radium-226 and radium-228, average ovarian mass, number and energy of alpha particles emitted, fraction of energy absorbed within the ovary, effective retention integrals and estimated photon irradiation. Time between marriage and pregnancy, number of pregnancies and number of live births served as surrogates for fertility. Radiation appeared to have no effect on fertility at estimated cumulative ovarian dose equivalents below 5 Sv; above this dose, however, statistically significant declines in both number of pregnancies and live births were observed. These trends persisted after multivariable adjustment for potential confounding variables and after exclusion of subjects contributing a potential classification or selection bias to the study. Additionally, the high-dose group experienced fewer live births than would have been expected based on population rates. There were no differences in time to first pregnancy between high- and low-dose groups. These results are consistent with earlier studies of gamma-ray exposures and suggest that exposure to high doses of radiation from internally deposited radium reduces fertility rather than inducing sterility.

Occupational Exposure Associated with Reproductive Dysfunction

“…Wayandt et al 71) reported preliminary data on semen analysis of radar operators and reported a reduction in the sperm count of military radar operators exposed to high frequency electromagnetic radiation. Earlier, Lancranjan et al 72) conducted a study among technicians exposed to microwaves for a period of 1 to 17 yr and reported a 3.3 to 10 Gy Permanent sterility 2 Internal alpha particle radiation dose Declines in number of pregnancies and live births Schieve et al 73) of more than 5 Sv to the ovary 3 Exposure to electric and magnetic fields Evidence is lacking for a close association between Shaw 74) women working in front of video display terminals and foetal loss and adverse pregnancy outcome significant decrease in the sperm concentration and the percentage of motile spermatozoa and significant increase in morphologically abnormal sperm as compared to control subjects.…”

“…Permanent sterility results from 3.3 to 10 Gy in a single dose or higher fractionated doses 67) . Schieve et al 73) evaluated internal alpha-particle radiation exposure and subsequent fertility among a cohort of women formerly employed in the radium dial industry. They reported that radiation appeared to have no effect on fertility at estimated cumulative ovarian dose equivalents below 5 Sv, but above this dose statistically significant declines in the number of pregnancies and live births were observed.…”