Dust diseases are traditionally understood as respiratory conditions, but emerging research suggests the effects of particulate exposure may extend beyond the lungs. This article explores the lung-brain axis, the growing evidence linking dust exposure with psychological and cognitive symptoms, and the implications this may have for the assessment of dust disease injuries and claims.
According to the Global Burden of Disease study, particulate exposure has been one of the main risk factors threatening public health worldwide, causing huge social costs (Li et al., 2025; Sang et al., 2022).
Dust diseases are traditionally understood as diseases of the lungs caused by inhaled particles. Respirable dust particles, typically smaller than 5 μm, can reach deep regions of the lung, where they may persist and provoke oxidative stress, tissue injury and inflammation. (Wei et al.,2026)
While many investigations have reported detriments of dust exposure to the respiratory system, there is limited research of its influence on other conditions, including mental health and neurological disorders (Li et al., 2025). Research indicates that inhaled particles can travel through the bloodstream and penetrate the brain, causing central and peripheral nervous system injury (Qi et al., 2022).
This damage however is not unidirectional but rather involves the gut-lung-brain-immune axis. This axis is the multidirectional communication network that connects the respiratory system with the nervous system and includes the microbiome and the immune system.
Our understanding of the role of the lung–brain axis in neurobehavioral regulation is emerging but studies have noted that exposures to particulates, acute or chronically, result in alteration in microbial communities that are linked to an elevated risk of mental disorders (Hosang et al., 2022; Nobile et al., 2023; Pelgrims et al., 2021).
Particle matters such as silica, coal, and asbestos may markedly elevate the risk of depression and anxiety, cognitive disorders, neuropsychological disorders and paraesthesia (Altu˘g et al. 2020; Best Rogowski et al., 2025; Hao et al., 2025; Li et al., 2024). The predicted mechanism includes microbes and their metabolites along with immune signalling, vagal nerve pathways and modulation of hypothalamic-pituitary-adrenal axis (Bajinka, 2022; Han et al 2026).
Particulate exposure may induce alteration of microbial communities resulting in lung dysbiosis with cell wall components (LPS) from gram negative bacteria causing severe inflammatory responses. These microbial alterations influence the immune response which signals to the brain, causing cognitive dysfunction (Hosang et al 2022; Kang et al 2024).
Our understanding of the lung-brain axis has direct implications for how dust disease claims are framed. If inhaled particles act on the brain through microbial and immune pathways, then depression, anxiety and cognitive change in a person with a dust disease may be seen as part of the disease process itself. These neuropsychological impacts are not merely a secondary reaction to breathlessness, disability or reduced quality of life.
Additionally, because of the bidirectional nature of the lung – brain axis, it needs to be considered that any neuroinflammatory process that influences brain health may potentially have a flow on effect to our lung health. This may include autonomic nervous system regulation of the lungs, pulmonary endothelial dysfunction, cough hypersensitivity or acute respiratory distress syndrome (Jai et al 2026; Li et al, 2025). Certainly, psychiatric conditions are genetically linked to respiratory conditions such as asthma.
As such, psychological and cognitive symptoms should be identified and assessed as part of the injury from the outset, not treated as a secondary condition. They may emerge before the respiratory diagnosis, or out of proportion to the degree of lung impairment and should not be discounted on that basis. Understanding the lung-brain axis is essential for addressing the psychological and neurological burden of dust diseases.
Dr Linda Thomas is a mucosal immunologist, clinical psychologist and Visiting Fellow at the Australian National University's National Centre for Epidemiology and Population Health. She has provided independent expert opinion on personal injury since 2004. Dr Thomas is Director of the Gut Feeling Clinic at Med-Psych. Her research on the gut-brain-immune axis is widely published, and she has presented at international congresses and holds patents for respiratory vaccines.
Altuğ, H., Fuks, K. B., Hüls, A., Mayer, A.-K., Tham, R., Krutmann, J., & Schikowski, T. (2020). Air pollution is associated with depressive symptoms in elderly women with cognitive impairment. Environment International, 136, Article 105448. https://doi.org/10.1016/j.envint.2019.105448
Bajinka, O., Simbilyabo, L., Tan, Y., Jabang, J., & Saleem, S. A. (2022). Lung-brain axis. Critical Reviews in Microbiology, 48(3), 257–269. https://doi.org/10.1080/1040841X.2021.1960483
Best Rogowski, C. B., Bredell, C., Shi, Y., Tien-Smith, A., Szybka, M., Fung, K. W., Hong, L., Phillips, V., Jovanovic Andersen, Z., Sharp, S. J., Woodcock, J., Brayne, C., Navaratnam, A., & Khreis, H. (2025). Long-term air pollution exposure and incident dementia: A systematic review and meta-analysis. The Lancet Planetary Health, 9(7), Article 101266. https://doi.org/10.1016/S2542-5196(25)00118-4
Han, J., Zhang, W., Zhang, Y., & Ding, J. (2026). Targeting the organ–brain axis: The modulatory role of peripheral organs in depression. Comprehensive Physiology, 16(4), Article e70216. https://doi.org/10.1002/cph4.70216
Hosang, L., Canals, R. C., van der Flier, F. J., Hollensteiner, J., Daniel, R., Flügel, A., & Odoardi, F. (2022). The lung microbiome regulates brain autoimmunity. Nature, 603(7899), 138–144. https://doi.org/10.1038/s41586-022-04427-4
Jia, Y., Liu, M., Tang, Z., & Xu, Y. (2026). Brain–lung axis and neuroimmune crosstalk in acute brain injury. Journal of Neuroinflammation. Advance online publication. https://doi.org/10.1186/s12974-026-04022-8
Kang, H., Huang, D., Zhang, W., Wang, J., Liu, Z., Wang, Z., Jiang, G., & Gao, A. (2024). Pulmonary flora-derived lipopolysaccharide mediates lung-brain axis through activating microglia: A mechanism behind cognitive dysfunction induced by inhalation of microplastics. Advanced Science, 11(44), Article 2404966. https://doi.org/10.1002/advs.style="margin:0 0 24px 0;font-size:16px;line-height:1.85;"> Li, W., Zhu, H., Zou, X., Ye, H., Zhong, J., Xiang, S., Lou, Y., Mao, J., Qi, L., Hu, X., Zhang, Y., Hou, J., Wang, B., Bode, C., Hoeft, A., Li, X., Zhang, K., Colonna, M., & Fang, X. (2025). A brain-to-lung signal from GABAergic neurons to ADRB2+ interstitial macrophages promotes pulmonary inflammatory responses. Immunity, 58(8), 2069–2085.e9. https://doi.org/10.1016/j.immuni.2025.05.005
Mazzone, S. B., Driessen, A. K., & Verzele, N. A. J. (2026). Peripheral and central neuroinflammatory mechanisms regulating vagal sensory circuit processing and cough in lung disease. Neuroimmunomodulation. Advance online publication. [DOI to be added]
Nobile, F., Forastiere, A., Michelozzi, P., Forastiere, F., & Stafoggia, M. (2023). Long-term exposure to air pollution and incidence of mental disorders. A large longitudinal cohort study of adults within an urban area. Environment International, 181, Article 108302. https://doi.org/10.1016/j.envint.2023.108302
Pelgrims, I., Devleesschauwer, B., Guyot, M., Keune, H., Nawrot, T. S., Remmen, R., Saenen, N. D., Trabelsi, S., Thomas, I., Aerts, R., & De Clercq, E. M. (2021). Association between urban environment and mental health in Brussels, Belgium. BMC Public Health, 21(1), Article 635. https://doi.org/10.1186/s12889-021-10557-7
Qi, Y., Wei, S., Xin, T., Huang, C., Pu, Y., Ma, J., Zhang, C., Liu, Y., Lynch, I., & Liu, S. (2022). Passage of exogeneous fine particles from the lung into the brain in humans and animals. Proceedings of the National Academy of Sciences of the United States of America, 119(26), Article e2117083119. https://doi.org/10.1073/pnas.2117083119
Wei, S., Ji, S., Wen, Y., Ku, T., & Shi, Y. (2026). Coal dust particles induce anxiety-like behaviors in the mice through lung-brain crosstalk. Ecotoxicology and Environmental Safety, 320, Article 120397. https://doi.org/10.1016/j.ecoenv.2026.120397