The United States Navy and Employees with Cancer: The Time for Change Is Now.

ABSTRACT: The US Navy, including the US Marine Corps and Naval Nuclear Propulsion Program (NNPP), has a robust radiological protection and monitoring program meeting (and typically exceeding, in the name of conservatism) federal law requirements. The program covers the variety of ways in which the Navy produces and uses ionizing radiation and radioactive sources: in medicine, nuclear ship propulsion and repair, industrial and aircraft radiography, and myriad other unique uses in carrying out its vital mission. In executing these programs, thousands of people across the world are employed as active-duty Sailors and Marines, government civilians, and government contractors. These workers include physicians, reactor operators, radiation safety officers, and nuclear repair workers, to name but a few. The health protection standards for these workers are promulgated in the publicly available Navy Medicine P-5055 Radiation Health Protection Manual (NAVMED P-5055), published February 2011 with Change 2 published December 2022, and are applicable to Navy and Marine Corps and NNPP radiation protection programs. The NAVMED P-5055 outlines the individual medical requirements for those qualified and able to receive exposure to ionizing radiation as part of their duties and requires that "Radiation workers receive focused medical examinations to establish whether or not cancer is present which would medically disqualify a person from receiving occupational radiation exposure." Additionally, without scientific or medical basis, the NAVMED P-5055 requires disqualifying those employees who have a history of cancer, cancer therapy, radiation therapy including radiopharmaceuticals received for therapeutic purposes, or bone marrow suppression from drawing dosimetry, entering radiation areas, or handling radioactive material. This policy, which exists regardless of lifetime occupational radiation dose or projected future radiation dose, applies to all cancers except adequately treated basal cell carcinoma. The policy is not supported by relevant scientific and medical literature; does not align with reasonable professional ethical standards; does not conform to US Navy radiological training, which stipulates the assumed increased risk of developing cancer from Navy and Marine Corps and NNPP occupational radiation exposure is small; and removes critical leadership and mentoring capability from the workforce unnecessarily. This article discusses in detail (1) this policy and its ramifications to the Navy and Marine Corps and NNPP workforce and (2) recommendations, benefits, and impacts for the Navy and Marine Corps and NNPP to remove this policy and still maintain a robust radiation protection program.

The History of the Linear No-Threshold Model and Recommendations for a Path Forward.

ABSTRACT: The intent of this paper and the accompanying video series is to inform the scientific community about the historical foundations that underpin the linear no-threshold (LNT) model's use for cancer risk assessment. There is a clear distinction here: this effort is about the history of how LNT came to be the regulatory paradigm and model for cancer risk assessment that it is today and not a discussion of the pros and cons of the LNT model. The overarching goal of this effort is to reframe the conversation around low-dose response models in light of this history and to determine how this history influences the scientific understanding of low-dose radiation responses. The timing of this series is intentional, as the International Commission on Radiological Protection (ICRP) has embarked on a mission to review the entire system of radiation protection. This effort necessarily requires rigorous scientific debate that must be based in fact. The history of the LNT model is paramount to this discussion, and it warrants consideration. Unfortunately, rather than engendering respectful debate, the topic of cancer risks associated with low dose radiation exposures has forged two disparate and sometimes contentious camps: (1) low doses, no matter how low, present some form of health risk and (2) an alternative model better represents the actual risks. The video series, conceived by John Cardarelli II, current President of the Health Physics Society (HPS), features Edward Calabrese, professor of toxicology in the School of Public Health and Health Sciences at the University of Massachusetts at Amherst, being interviewed by HPS Past-President Barbara Hamrick, CHP, JD, with support from Daniel Sowers, the Chair of the HPS Public Information Committee, and HPS Executive Director Brett Burk. Emily Caffrey, the Chief Editor of our Ask-the-Experts website (https://hps.org/publicinformation/ate/), was invited to watch the completed series as an independent peer reviewer. Further, an email address, factcheck@hps.org, was created to allow for peer-review by the scientific community to facilitate ongoing discussion and allow for corrections to the record as necessary. It is the sincere hope of this team that this work inspires new discussions about the system of radiological protection. We encourage everyone in this field to watch all 22 episodes to be informed about the underpinnings of current regulatory policy in the US.

Dose simulations of an early 20th century kilovoltage pneumonia radiotherapy technique performed with a modern fluoroscope.

To simulate an early 20th century viral pneumonia radiotherapy treatment using modern fluoroscopy and evaluated it according to current dose guidelines. Monte Carlo was used to assess the dose distribution on an anthropomorphic phantom. Critical organs were: skin, breasts, esophagus, ribs, vertebrae, heart, thymus, and spinal cord. A 100 kVp beam with 3 mm Al HVL, 25 × 25 cm2 posterior-anterior (PA) field and 50 cm source-to-surface distance were simulated. Simulations had a resolution of 0.4 × 0.4 × 0.06 cm3 and a 6% uncertainty. Hundred percent dose was normalized to the skin surface and results were displayed in axial, coronal, and sagittal planes. Dose volume histograms were generated in MATLAB for further analysis. Prescription doses of 0.3, 0.5, and 1.0 Gy were applied to the 15% isodose for organ-dose comparison to current tolerances and potential risk of detriment. Ninety-five and ninety-seven percent of the right and left lung volumes, respectively, were well-covered by the 15% isodose line. For the 0.3, 0.5, and 1.0 Gy prescriptions, the maximum skin doses were 2.9, 4.8, and 9.6 Gy compared to a 2.0 Gy transient erythema dose threshold; left/right lung maximum doses were 1.44/1.46, 2.4/2.4, and 4.8/4.9 Gy compared to a 6.5 Gy pneumonitis and 30 Gy fibrosis thresholds; maximum heart doses were 0.5, 0.9, and 1.8 Gy compared to the 0.5 Gy ICRP-recommendation; maximum spinal cord doses were 1.4, 2.3, and 4.6 Gy compared to 7.0 Gy single fraction dose threshold. Maximum doses to other critical organs were below modern dose thresholds. A 100 kVp PA field could deliver a 0.3 Gy or 0.5 Gy dose without risk of complications. However, a 1.0 Gy dose treatment could be problematic. Critical organ doses could be further reduced if more than one treatment field is used.

Presidential Perspectives: Women's Views From the Top.

This paper presents the perspectives of past presidents of the Health Physics Society who also happen to be women. Only 6 out of 63 Society presidents have been women, and of these six, five are still living and briefly reflect on their experiences here, alongside a brief discussion of the first female president of the Society. These perspectives provide historical insight into the evolution and happenings of the Society as well as adding personal touches to the office of the president that hopefully will encourage junior Society members to consider serving.