Dr. Laura Manenti, an experimental particle physicist at the University of Sydney, has created the first environmental radioactivity map of Sydney after noticing high radiation levels upon her arrival from Abu Dhabi. Using a portable gamma ray detector, she recorded significant radiation counts in her office, prompting her to investigate further. The project's findings revealed Glebe as a hotspot for background radiation, mainly due to the region's geological composition of sandstone and shale that contain higher levels of uranium and thorium. The study, published in *The Journal of Environmental Radioactivity*, involved taking gamma ray readings across 100 locations in Sydney and analyzing soil samples for natural radionuclides. Even though Sydney has higher radiation levels compared to other cities, the readings are still within safe limits. The team isolated terrestrial radiation from cosmic radiation by measuring on Sydney Harbour, adding precision to their results. The average exposure in the surveyed areas amounted to 0.24 millisieverts per year, comparable to the natural radiation emitted by the human body. Researchers emphasized that while the radiation varies across locations due to geological factors, it remains significantly lower than the exposure levels associated with increased cancer risks. This mapping project not only provides a baseline for future radiation assessments, especially in the event of nuclear accidents, but also helps understand radon gas risks, a significant health concern in certain regions. The team aims to expand their research to include broader areas through citizen science initiatives.
Sat, 21 Feb 2026 18:00:00 GMT | SMH.com.au