Machine learning-enhanced stochastic uncertainty and sensitivity analysis of the ICRP human respiratory tract model for an inhaled radionuclide.

The International Commission on Radiological Protection (ICRP) has developed the reference Human Respiratory Tract Model (HRTM), detailed in ICRP Publications 66 and 130, to estimate the deposition and clearance of inhaled radionuclides. These models utilize reference anatomical and physiological parameters for particle deposition (PD). Biokinetic models further estimate retention and excretion of internalized particulates, aiding the derivation of inhalation dose coefficients (DC).

Mortality follow-up of Fernald Feed Materials Production Center workers exposed to uranium from 1951 to 1985.

Objective: This follow-up study of uranium processing workers at the Fernald Feed Materials Production Center examines the relationship between radiation exposure and cancer and non-cancer mortality among 6403 workers employed for at least 30 days between 1951 and 1985.

Methods: We estimated cumulative, individual, annualised doses to 15 organs/tissues from external, internal and radon exposures. Vital status and cause of death were ascertained in 2017.

Revisiting the Historic Strontium-90 Ingestion Beagle Study Conducted at the University of California Davis: Opportunity in Archival Materials.

Strontium-90 is a radionuclide found in high concentrations in nuclear reactor waste and nuclear fallout from reactor accidents and atomic bomb explosions. In the 1950s, little was known regarding the health consequences of strontium-90 internalization. To assess the health effects of strontium-90 ingestion in infancy through adolescence, the Atomic Energy Commission and Department of Energy funded large-scale beagle studies at the University of California Davis.

Adjustment for duration of employment in occupational epidemiology.

Purpose: In occupational epidemiology, the healthy worker survivor effect can manifest as a time-dependent confounder because healthier workers can accrue greater amounts of exposure over longer periods of employment. For example, in occupational studies of radiation exposure that focus on cumulative annualized radiation dose, workers can accrue greater amounts of cumulative radiation exposure over longer periods of employment, while workers with longer periods of employment can transition into jobs with a reduced potential for annualized radiation exposure. The extent to which confounding arising from the healthy worker survivor effect impacts radiation risk estimates is unknown.

Moon, Mars and Minds: Evaluating Parkinson's disease mortality among U.S. radiation workers and veterans in the million person study of low-dose effects.

Background: Radiation is one of the most important stressors related to missions in space beyond Earth's orbit. Epidemiologic studies of exposed workers have reported elevated rates of Parkinson's disease. The importance of cognitive dysfunction related to low-dose rate radiation in humans is not defined.

Mortality among Tennessee Eastman Corporation (TEC) uranium processing workers, 1943-2019.

Background: There are few occupational studies of women exposed to ionizing radiation. During World War II, the Tennessee Eastman Corporation (TEC) operated an electromagnetic field separation facility of 1152 calutrons to obtain enriched uranium (U) used for the Hiroshima atomic bomb. Thousands of women were involved in these operations.

Mortality from leukemia, cancer and heart disease among U.S. nuclear power plant workers, 1957-2011.

Background: The aim of the Million Person Study of Low-Dose Health Effects (MPS) is to examine the level of radiation risk for chronic exposures received gradually over time and not acutely as was the case for the Japanese atomic bomb survivors. Nuclear power plant (NPP) workers comprise nearly 15 percent of the MPS. Leukemia, selected cancers, Parkinson's disease, ischemic heart disease (IHD) and other causes of death are evaluated.

Mortality among workers at the Los Alamos National Laboratory, 1943-2017.

Background: During World War II (WWII), the Manhattan Engineering District established a secret laboratory in the mountains of northern New Mexico. The mission was to design, construct and test the first atomic weapon, nicknamed 'The Gadget' that was detonated at the TRINITY site in Alamogordo, NM. After WWII, nuclear weapons research continued, and the laboratory became the Los Alamos National Laboratory (LANL).

Cohort profile: four early uranium processing facilities in the US and Canada.

Purpose: Pooling of individual-level data for workers involved in uranium refining and processing (excluding enrichment) may provide valuable insights into risks from occupational uranium and external ionizing radiation exposures.

Methods: Data were pooled for workers from four uranium processing facilities (Fernald, Mallinckrodt and Middlesex from the U.S.

Mortality among U.S. military participants at eight aboveground nuclear weapons test series.

Background: Approximately 235,000 military personnel participated at one of 230 U.S. atmospheric nuclear weapons tests from 1945 through 1962.

Updated mortality analysis of the Mallinckrodt uranium processing workers, 1942-2012.

Purpose: Mallinckrodt Chemical Works (MCW) was the earliest uranium processing facility in the United States, and in 1942 produced the uranium oxide used for the first sustained and controlled nuclear fission chain-reaction at the University of Chicago. A second follow-up through 2012 was conducted of 2514 White male workers employed 1942-1966 at the MCW for dose-response analyses for selected causes of death.

Materials And Methods: Organ/tissue-specific dose reconstruction included both external (12,686 MCW film badge records, 210 other facility film badge records, and 31,297 occupational chest x-rays) and internal sources of uranium and radium (39,451 urine bioassays, 2341 breath radon measurements, and 6846 ambient radon measurements).

Sex-specific lung cancer risk among radiation workers in the million-person study and patients TB-Fluoroscopy.

Background: The study of Japanese atomic bomb survivors, exposed briefly to radiation, finds the risk of radiation-induced lung cancer to be nearly three times greater for women than for men. Because protection standards for astronauts are based on individual lifetime risk projections, this sex-specific difference limits the time women can spend in space. Populations exposed to chronic or fractionated radiation were evaluated to learn whether similar differences exist when exposures occur gradually over years.

Evaluation of statistical modeling approaches for epidemiologic studies of low-dose radiation health effects.

Purpose: A substantial body of epidemiologic literature addresses risks associated with occupational radiation exposure but comparing results between studies is often difficult as different statistical models are commonly used. It is unclear whether different methods produce similar results for estimates of radiation risk when applied to the same data. The goal of this study was to compare the radiation risk estimates for leukemia other than chronic lymphocytic leukemia (non-CLL) and ischemic heart disease (IHD) produced by both Cox and Poisson regression models for time-dependent dose-response analyses of occupational exposure.

Historical perspective on the department of energy mortality studies: focus on the collection and storage of individual worker data.

Purpose: To present how the Department of Energy's (DOE) Comprehensive Epidemiologic Data Resource (CEDR) is integrated into the Million Person Study of Low Dose Health Effects (MPS). The history of DOE's worker health surveillance and its epidemiology program are described.

Methods And Materials: A standard protocol is used to extract data from CEDR for use in the MPS.

Clinical and laboratory factors contributing to uninterpretable beryllium lymphocyte proliferation tests (BeLPT).

Background: The beryllium lymphocyte proliferation test (BeLPT), has become the principal clinical test for detecting beryllium sensitization and chronic beryllium disease. Uninterpretable BeLPT results can occur in a small but significant proportion of tests from poor lymphocyte growth (PG) or over proliferation of lymphocytes (OP). The clinical and laboratory causes of uninterpretable results are not known.

A Review and Meta-Analysis of Occupational Titanium Dioxide Exposure and Lung Cancer Mortality.

Objective: A review of studies of occupational titanium dioxide (TiO2) exposure was conducted, and results from the three industry-based cohort mortality studies were summarized using meta-analysis.

Methods: Summary standardized mortality ratios (SSMR) and summary Cox regression coefficients from exposure-response models were derived using random effects models.

Results: Results from studies of 24,312 TiO2 production workers were combined.

Dosimetry is Key to Good Epidemiology: Workers at Mallinckrodt Chemical Works had Seven Different Source Exposures.

Mallinckrodt Chemical Works was the earliest uranium processing facility in the Manhattan Project, beginning in 1942. Even then, concern existed about possible health effects resulting from exposure to radiation and pitchblende dust. This concern was well founded as the facility processed Belgian Congo pitchblende ore that was up to 60% pure uranium with high U content and up to 100 mg of radium per ton.

The Past Informs the Future: An Overview of the Million Worker Study and the Mallinckrodt Chemical Works Cohort.

The purpose of this paper is to present an overview of ongoing work on the Million Worker Study (MWS), highlighting some of the key methods and progress so far as exemplified by the study of workers at the Mallinckrodt Chemical Works (MCW). The MWS began nearly 25 y ago and continues in a stepwise fashion, evaluating one study cohort at a time. It includes workers from U.

Emergency medical services transport delays for suspected stroke and myocardial infarction patients.

Background: Prehospital delays in receiving emergency care for suspected stroke and myocardial infarction (MI) patients have significant impacts on health outcomes. Use of Emergency Medical Services (EMS) has been shown to reduce these delays. However, disparities in EMS transport delays are thought to exist.