Nanoparticles present one of the biggest risks among the emerging occupational risks. Early health risk assessment studies on the effects of ambient nanoparticles are required to assure safety of exposed workers. The present study aimed at exploring the levels of biomarker of endothelial dysfunction (vascular cell adhesion molecule, VCAM-1) and high-sensitivity C-reactive protein, and spirometric functions among nanoparticle-exposed workers. The comparative cross-sectional study included 46 nanoparticle-exposed workers and 45 non-exposed workers. All participants filled an interview questionnaire and were submitted to measurement of ventilatory lung functions. Also, blood samples were taken from all the studied group to measure the former biomarkers. Diffusion size counter and electron microscopy were used to measure the emitted nanoparticles from research labs. Dimensions of ambient nanoparticles ranged from 31-81 nanometer. Mean serum VCAM-1 level was significantly higher in exposed group compared to non-exposed group (p < 0.05). Nanoparticle-exposed workers show significantly lower mean % predicted maximum expiratory flow (MEF₅₀ and MEF₇₅) compared to non-exposed ones. In the exposed group, a significant negative correlation was found between biomarker of endothelial dysfunction and % predicted maximum expiratory flow (MEF₅₀). Elevated serum VCAM-1 among nanoparticle-exposed workers suggests presence of potential risk for endothelium of blood vessels.