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Standardizing minimally invasive mucosal biopsies, spatially resolved metagenomics, and contamination controlssuch as synthetic spike-in standards and dual-indexed barcodingwill enhance the reproducibility and accuracy of microbiome data [135,136,137]

In some cases, e-cigarettes stimulate the production of ROS in alveolar macrophages, causing lung epithelial damage and neutrophil influx at injury sites, resulting in aggravated inflammation, mucus production, and destruction of alveolar cells, leading to airway obstruction [53]

doi:10.1136/tobaccocontrol-2018-054389

Microbiol Spectr

Car exhaust fumes also produce this substance, and it is fatal in large doses