Solid State Nuclear Track Detectors (SSNTDs) are used extensively for monitoring alpha particle radiation, neutron flux and cosmic ray radiation. Radon gas inhalation is regarded as being a significant contributory factor to lung cancer deaths in the UK each year. Gas concentrations are often monitored using CR39 based SSNTDs as the natural decay of radon results in alpha particles which form tracks in these detectors. Such tracks are normally etched for about 4 hours to enable microscopic analysis. This study examined the effect of etching time on the appearance of alpha tracks in SSNTDs by collecting 2D and 3D image datasets using laser confocal imaging techniques. Etching times of 2 to 4 hours were compared and marked differences were noted in resultant track area. The median equivalent diameters of tracks were 20.2, 30.2 and 38.9 µm for etching at 2, 3 and 4 hours respectively. Our results indicate that modern microscope imaging can detect and image the smaller size tracks seen for example at 3 hours etching time. Shorter etching times may give rise to fewer coalescing tracks although there is a balance to consider as smaller track sizes may be more difficult to image. Thus etching for periods of less than 4 hours clearly merits further investigation as this approach has the potential to improve accuracy in assessing the number of tracks.
<p class="western">Environmental exposomes in the natural environment include silicate ash from volcanic eruptions and wind-blown mineral dust, both of which may promote lung disease if subjected to prolonged exposure. In order to develop strategies for risk mitigation in populations subjected to hazardous minerals in the environment, it may be useful to integrate mineral chemical composition with the three-dimensional particle characteristics (e.g. shape and surface characteristics) as a means to fully assess potential mechanisms of toxicity. In this contribution we show how a combination of confocal laser microscopy, a non-destructive technique capable of resolving true 3D geometry of PM<sub>10 </sub>and PM<sub>2.5 </sub>particles, with spectroscopic analysis, provides a novel and rapid way to assess the minero-chemical properties of potentially hazardous airborne material (Wertheim et al. 2017).</p> <p class="western">Initial results using samples from the 2021 La Palma volcanic eruption (volcanic silicate ash) show that volcanic particles (angular forms) increased pneumococcal adherence to A549 lung epithelial cells in vitro (Miyashita et al. 2022). Preliminary confocal images of airborne mineral dust originating in Saharan Africa and deposited on Tenerife during a sandstorm (Calima event, February 2020), show more <span lang="en-US">rounded, </span>mature particle shapes than volcanic ash, yet with clear variations in surface features. Hence we are investigating whether Calima particles could also affect pneumococcal adherence to lung cells in vitro.</p> <p class="western">Applying such a multidisciplinary approach combining results from different techniques may help to raise awareness of and prevent longer-term occupational hazards in populations such as the Canary Islands, where residents are at risk of multiple sources of exposure to both volcanic ash and inorganic dust.</p> <p class="western"><strong>References</strong></p> <p class="western">Wertheim D, Gillmore G, Gill I, Petford N. High resolution 3D confocal microscope imaging of volcanic ash particles. Sci Total Environ. 2017 Jul 15;590-591:838-842. DOI: 10.1016/j.scitotenv.2017.02.230.</p> <p class="western">Miyashita L, Coldwell B, Wertheim D, Giddens R, Gill I, Petford N, P&#233;rez N and Grigg J. La Palma Volcanic Ash Particles Increase Susceptibility to Pneumococcal Infection In Vitro. European Respiratory Journal 2022 60: 3163; DOI: 10.1183/13993003.congress-2022.3163</p>
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.