A nested case-control study was undertaken to identify characteristics distinguishing white females dying from suicide from white females dying from all other types of injuries and those dying from noninjury causes. Two separate analyses were presented: one contrasting the 19 suicide deaths and the 41 other injury deaths, the other contrasting the 19 suicide deaths and 76 noninjury deaths. External radiation monitoring status and job classification both showed an association with risk of suicide when suicide deaths were compared with noninjury deaths. An association was also found between suicide and external radiation monitoring status when comparing suicide to deaths from all other injuries. No significant associations were found between risk of suicide and duration of employment, plutonium monitoring status, or marital status. Education was controlled in all comparisons.
The single analytic file (LASUFILE) pertains to 136 white females employed at LANL. This number includes all suicide, all other injury deaths, and a 4:1 random sample of all other deaths. These 136 known-dead workers were selected from the file used in a 1987 LANL female cohort study (LAFEMA01). External monitoring data consist of dates (in decimalized notation) on which the worker was first monitored, first received a positive exposure, first received 1 rem whole-body dose, first received 5 rems whole-body dose, and first received 10 rems whole-body dose. Whole-body dose was defined as the sum of all tritium, neutron, and penetrating gamma readings. External readings were available through December 31, 1981.
Only eight of the females in this file were monitored for plutonium. Internal exposure data consist of plutonium-239 body burdens that were calculated by the PUQFUA computer code, the official code used at LANL to estimate body burdens from bioassay data. The date of first positive uptake of plutonium was hand- abstracted from data valid through 1986. Plutonium monitoring data include isotope type; first sample date (in decimalized notation); last sample date (decimalized); and estimated whole-body burdens (both nCi and nCi-years) as of December 31, 1983, as of December 31, 1984, and as of the last sample date.
LANL has been a center for research in nuclear physics and weapons development since the 1940s. Sources of occupational exposures include external radiation, primarily gamma, and potential internal deposition of plutonium-238 and plutonium- 239. Pocket chambers or film dosimeters were used for personnel monitoring until 1980, when they were replaced with thermoluminescent dosimeters. Formal bioassay programs to monitor for internal exposures were begun in 1945. Results of both types of monitoring programs reflect technological improvements and changes in concepts and models.
L.D. Wiggs, C. A. Weber, and E. T. Lee, "Suicide Mortality Among Female Nuclear Industry Workers," (abstract) in Proceedings of the 116th Annual Meeting of the American Public Health Association, Boston, MA, November 13-17, 1988. p. 46. /
J.N.P. Lawrence, "PUQFUA, An IBM 704 Code for Computing Plutonium Body Burdens," Health Phys. 8, 61-66 (1962).
END_STDY 12/31/1981