Abstract:Objective To study the potential harmful effects of brake source particles. Methods Grind the brake pad particles or antimony sulfide particles. Subsequently, the mice were exposed through tracheal perfusion for 1 month to observe pathological changes in in the lungs, heart, and liver, and flow cytometry was used to analyze the changes in peripheral blood macrophages and regulatory T cells (Treg). Results After exposure, there was deposition of foreign substances in the alveolar wall of mice, with obvious infiltration of inflammatory cells around blood vessels, which worsened with increasing exposure concentration. In addition, pathological changes such as vascular inflammation and microthrombosis in the heart, and hepatocyte swelling in the liver were observed. Treg cells in peripheral blood decreased and macrophages increased in the antimony sulfide group and low-dose brake pad particles group, while the proportion of M2-type macrophages decreased. Conclusions Exposure to brake pad particles and their component antimony sulfide particles has varying degrees of toxic effects on the lung, heart, and liver of mice, and has a impact on the immune system, indicating the potential health hazards of brake-derived air pollution.