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We are constantly exposed to nanoparticles, some of which can have a negative impact on our health. In this study the effect on thromboinflammation by airborne nanoparticles from the iron alloys found on the rails, wheels and the contact rail of subway are studied using a human whole blood loop model. In the bloodloops particle samples are added to whole blood and incubated on a rotating wheel to simulate the bloodstream. After incubation the plasma is separated and further analysed with Sandwich ELISA and WES Immunoassay. By studying the generation of complement and coagulation- and contact-system activation markers C3a, sC5b-9, TAT, KK-C1INH and HMWK a good insight on how the nanoparticles affect the coagulation-, complement- and contact system were provided. All particle samples mainly activated the coagulation- and contact system, meaning that these particles mainly have a thrombotic effect. However, the contact system can also lead to inflammatory responses by the generation of bradykinin and thereby causing thromboinflammation – without the complement system being involved as the main system causing inflammation. The ”Third Rail” sample triggered the coagulation system, measured with TAT, significantly more than the other particle samples. This could be because the composition of this sample differed from the other particle samples by containing a bigger proportion of silica and carbon nanoparticles. The findings of this study have provided more understanding of how these nanoparticles affects the human health and will be useful for further studies of these nanoparticles from the subway.