Excess relative risk (ERR) estimates from the A-bomb survivors and from selected studies of persons exposed to protracted low-LET external ionizing radiation.

<p>* Doses are external colon dose in mGy for Mayak workers, weighted colon dose in mGy for the atomic bomb survivors, Hp(10) in mSv for the 15-country and NRRW studies.(Hp(10) is the equivalent dose at a tissue depth of 10 mm beneath a dosimeter); stomach dose in mGy for the Techa river cohort</p><p>† 90% confidence intervals used for comparison with published results in the 15-country and NRRW studies</p><p>†† weighted average with weights of 0.75 for men and 0.25 for women to reflect the sex ratio in the Mayak worker cohort</p><p>‡ These populations are predominantly male</p><p>§ The estimate presented here is based on the 15-country study results withwith the Canadian data excluded ([<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0117784#pone.0117784.ref029" target="_blank">29</a>], page 405).). This estimate was used because of concerns about the Canadian data usedused in that study. This concerns have beenbeen supported by the recently published re-analysis of the Canadian workerworker data given in [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0117784#pone.0117784.ref034" target="_blank">34</a>]. The ERR/SvSv estimate for using all of the 15-country data is 0.59 (95% CI <0 to 1.5, [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0117784#pone.0117784.ref029" target="_blank">29</a>], page 403).</p><p>** There was no evidence that risk differed by sex in this cohort.</p><p>Excess relative risk (ERR) estimates from the A-bomb survivors and from selected studies of persons exposed to protracted low-LET external ionizing radiation.</p

Site-specific excess relative risk per Gy estimates^‡ and number of external exposure associated cases.

<p>‡ The risk estimates in this table were not adjusted for plutonium exposure since, as noted in the text, there is no evidence of significant effects of plutonium for all of these cancers as a group or for any specific type of cancer considered here.</p><p>* Analyses were limited to cases seen in men with cases among women (1 bladder cancer and 2 laryngeal cancers) included in the remainder.</p><p>Site-specific excess relative risk per Gy estimates^{<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0117784#t007fn001" target="_blank">‡</a>} and number of external exposure associated cases.</p

Radiation Effects on Mortality from Solid Cancers Other than Lung, Liver, and Bone Cancer in the Mayak Worker Cohort: 1948–2008

<div><p>Radiation effects on mortality from solid cancers other than lung, liver, and bone cancer in the Mayak worker cohort: 1948–2008. The cohort of Mayak Production Association (PA) workers in Russia offers a unique opportunity to study the effects of prolonged low dose rate external gamma exposures and exposure to plutonium in a working age population. We examined radiation effects on the risk of mortality from solid cancers excluding sites of primary plutonium deposition (lung, liver, and bone surface) among 25,757 workers who were first employed in 1948–1982. During the period 1948–2008, there were 1,825 deaths from cancers other than lung, liver and bone. Using colon dose as a representative external dose, a linear dose response model described the data well. The excess relative risk per Gray for external gamma exposure was 0.16 (95% CI: 0.07 – 0.26) when unadjusted for plutonium exposure and 0.12 (95% CI 0.03 – 0.21) when adjusted for plutonium dose and monitoring status. There was no significant effect modification by sex or attained age. Plutonium exposure was not significantly associated with the group of cancers analyzed after adjusting for monitoring status. Site-specific risks were uncertainly estimated but positive for 13 of the 15 sites evaluated with a statistically significant estimate only for esophageal cancer. Comparison with estimates based on the acute exposures in atomic bomb survivors suggests that the excess relative risk per Gray for prolonged external exposure in Mayak workers may be lower than that for acute exposure but, given the uncertainties, the possibility of equal effects cannot be dismissed.</p></div

Cancer cases by sex and site.

<p>Cancer cases by sex and site.</p

Non-smoker baseline cancer mortality rates and their sex ratio.

<p>Non-smoker baseline rates for mortality from solid cancers in organs other than lung, liver, bone or connective tissue in the Mayak worker cohort (upper panel) with age-specific sex ratios (lower panel).</p

Definition and selected characteristics of plutonium exposure surrogate categories.

<p>† 5-year lagged cumulative dose at end of follow-up. Internal dose means based on workers with urine bioassay-based dose estimates.</p><p>Definition and selected characteristics of plutonium exposure surrogate categories.</p

External exposure dose response for solid cancers other than lung liver and bone.

<p>A) External exposure dose response function for solid cancers at sites of than lung, live, bone, or connective tissue. B) The same plot for doses below 1.5 Gy. The solid line is the fitted linear dose response, the points are ERR estimates in dose categories. The thick dashed line is a non-parametric smooth fit to the categorical estimates while the thin dashed lines indicate plus or minus one standard error from the smoothed curve. The models used in this analysis included no adjustment for plutonium exposure.</p

Characteristics of dose distributions for the mortality analysis of the Techa River <i>in Utero</i> Exposed Cohort (TRCIU; <i>n</i> = 11,490), the Mayak Female Workers’ Offspring Cohort exposed in utero (MWOC; <i>n</i> = 5,331), and Urals Prenatally Exposed Cohort (UPEC, n = 16,821).

<p>Characteristics of dose distributions for the mortality analysis of the Techa River <i>in Utero</i> Exposed Cohort (TRCIU; <i>n</i> = 11,490), the Mayak Female Workers’ Offspring Cohort exposed in utero (MWOC; <i>n</i> = 5,331), and Urals Prenatally Exposed Cohort (UPEC, n = 16,821).</p

Incidence and Mortality of Solid Cancers in People Exposed <i>In Utero</i> to Ionizing Radiation: Pooled Analyses of Two Cohorts from the Southern Urals, Russia

<div><p>Background</p><p>Previous studies have shown that acute external <i>in utero</i> exposure to ionizing radiation can increase cancer risk. It is not known whether chronic exposure at low dose rates, including due to radionuclide intake, influences the lifetime risk of solid cancers in the offspring. The objective of this study was to investigate solid cancer risk after <i>in utero</i> irradiation.</p><p>Methods</p><p>Cancer incidence and mortality over a 60-year period (from January 1950 to December 2009) were analyzed in the Urals Prenatally Exposed Cohort (UPEC). The cohort comprised <i>in utero</i> exposed offspring of Mayak Production Association female workers and of female residents of Techa River villages. Some of the offspring also received postnatal exposure, either due to becoming radiation workers themselves or due to continuing to live in the contaminated areas of the Techa River. The mortality analyses comprised 16,821 subjects (601,372 person-years), and the incidence analyses comprised 15,813 subjects (554,411 person-years). Poisson regression was used to quantify the relative risk as a function of the <i>in utero</i> soft tissue dose (with cumulative doses up to 944.9 mGy, mean dose of 14.1 mGy in the pooled cohort) and the postnatal stomach dose for solid cancer incidence and mortality.</p><p>Results</p><p>When a log-linear model was used, relative risk of cancer per 10 mGy of <i>in utero</i> dose was 0.99 (95% confidence interval (CI) = 0.96 to 1.01) based on incidence data and 0.98 (CI = 0.94 to 1.01) based on mortality data. Postnatal exposure to ionizing radiation was positively associated with the solid cancer risk in members of the UPEC, with a relative risk of 1.02 per 10mGy CI = 1.00 to 1.04).</p><p>Conclusions</p><p>No strong evidence was found that chronic low-dose-rate exposure of the embryo and fetus increased the risk of solid cancers in childhood or in adulthood. For both incidence and mortality, a tendency towards a decreased relative risk was noted with increasing doses to soft tissues of the fetus. Further follow-up will provide more precise radiation risk estimates of solid cancer as cohort members are approaching their 60s and cancer becomes more common.</p></div

Characterization of the status at the end of the follow up of the Urals Prenatally Exposed Cohort:, sex, birth year, ethnicity, and dose.

<p>Characterization of the status at the end of the follow up of the Urals Prenatally Exposed Cohort:, sex, birth year, ethnicity, and dose.</p