Crystalline killer: the molecular cascade of silica toxicity from inflammation to fibrosis

Silicosis, a progressive fibrotic lung disease caused by inhalation of crystalline silica, is resurging due to increased exposure in high-risk industries such as engineered stone fabrication. Characterised by asymptomatic onset and delayed diagnosis, it remains a major occupational health concern. This review synthesises current understanding of silica-induced lung injury, highlighting the physicochemical properties of silica that drive its biological reactivity and persistence in the lung.

Silica deposition induces lysosomal rupture, oxidative stress, and NLRP3 inflammasome activation, leading to programmed cell death, neutrophil extracellular trap formation, and chronic inflammation. These events culminate in fibrotic remodelling through epithelial-mesenchymal transition and fibroblast activation. Emerging evidence implicates damage-associated molecular patterns and exosomal microRNAs in amplifying fibrogenic signalling. Biomarkers and therapeutic targets may enable earlier diagnosis and intervention.

By bridging mechanistic insights with translational strategies, this review supports precision approaches for screening, monitoring, and treating silica-related lung disease.