Age at exposure to ionising radiation and cancer mortality among Hanford workers: follow up through 1994

Abstract

Background: Studies of workers at the plutonium production factory in Hanford, WA have led to conflicting conclusions about the role of age at exposure as a modifier of associations between ionising radiation and cancer. Aims: To evaluate the influence of age at exposure on radiation risk estimates in an updated follow up of Hanford workers. Methods: A cohort of 26 389 workers hired between 1944 and 1978 was followed through 1994 to ascertain vital status and causes of death. External radiation dose estimates were derived from personal dosimeters. Poisson regression was used to estimate associations between mortality and cumulative external radiation dose at all ages, and in specific age ranges. Results: A total of 8153 deaths were identified, 2265 of which included cancer as an underlying or contributory cause. Estimates of the excess relative risk per Sievert (ERR/Sv) for cumulative radiation doses at all ages combined were negative for all cause and leukaemia and positive for all cancer and lung cancer. Cumulative doses accrued at ages below 35, 35-44, and 45-54 showed little association with mortality. For cumulative dose accrued at ages 55 and above (10 year lag), the estimated ERR/Sv for all cancers was 3.24 (90% CI: 0.80 to 6.17), primarily due to an association with lung cancer (ERR/Sv: 9.05, 90% CI: 2.96 to 17.92). Conclusions: Associations between radiation and cancer mortality in this cohort are primarily a function of doses at older ages and deaths from lung cancer. The association of older age radiation exposures and cancer mortality is similar to observations from several other occupational studies.

Examining temporal effects on cancer risk in the international nuclear workers’ study

“…The excess risk of all solid cancers and lung cancer appeared restricted to exposure ages 35 years or greater. Evidence from other studies has also suggested associations between radiation dose and lung cancer that are stronger at older exposure ages . However, methods have varied among studies and differences in age‐risk patterns between studies are apparent.…”

“…Evidence from other studies has also suggested associations between radiation dose and lung cancer that are stronger at older exposure ages. 7,[22][23][24] However, methods have varied among studies and differences in age-risk patterns between studies are apparent. These inconsistencies may result from underpowered analyses given low baseline cancer risk at young attained ages.…”

Mortality of older construction and craft workers employed at department of energy (DOE) nuclear sites

“…In a case-control study in four DOE sites, Wing et al [2000] observed an association between the risk of multiple myeloma and low-level whole body penetrating ionizing radiation dose at older ages. A specific association between cancer mortality and radiation doses accrued at older ages has been reported in studies of Hanford workers [Kneale et al, 1984;Kneale and Stewart, 1993], and this association appears particularly strong for lung cancer [Wing and Richardson, 2005].…”

Geospatial Technologies and the Geographies of Hope and Fear

“…Such a prospect then becomes one of the more insidious aspects of the Panopticon. Not only will surveillance mold our activities into a constrained pattern, but our past geographies will truly come back to haunt us, much as they have for those who worked in the Hanford nuclear facilities (e.g., Gilbert, Cragle, and Wiggs 1995;Wing and Richardson 2005), but in far more subtle ways.…”