MPO and lung disorder: Persistent inflammation of neutrophils has been implicated in nanoparticle‐induced lung disorders, and Tomonaga et al.20reported that in an animal study with some nanomaterials with varieties of toxicity to lung, a persistent increase in myeloperoxidase released from neutrophils was correlated with inflammatory cell infiltration, lung damage analyzed from the increase of LDH release, and oxidative stress in lung.