Dosimetry Testing for a New In Vivo X-ray Fluorescence Measurement System.

Abstract: Lead exposure poses severe health risks to individuals, impacting cognitive function, growth, learning, and behavior. Current lead detection methods, primarily blood testing and x-ray fluorescence (XRF) of bone, have limitations. This study introduces a novel in vivo XRF measurement system using K-shell energies of lead, addressing limitations of previous methods. The study aimed to characterize beam directionality, subject radiation dose, and operator occupational exposure. Using a high-energy x-ray tube and room-temperature detectors, various parameters were assessed with bone and tissue phantoms. Dose measurements were taken by altering voltage, current, and shielding. Scatter and spatial measurements highlighted increased scatter with bone and tissue presence, emphasizing the safest positions for bystanders and operators. Results exhibited expected dose rate changes with varying parameters, showcasing the impact of bone and tissue on scatter radiation. The system's total body effective dose (with an 8-mm molybdenum shielding indicating minimal risk compared to established public dose limits) for an adult was 1.94 μSv; for a child aged 10 y, it was 3.28 μSv. This system demonstrates promising capabilities for lead exposure monitoring, offering negligible occupational exposure and minimal risk to individuals being scanned. Its safety and efficacy position it as a valuable tool in assessing lead exposure, potentially improving preventive measures.