This book explores human biomonitoring (HBM) as a method to evaluate chemical exposure and its related health effects, with a specific focus on short half-life chemicals and mycotoxins. This volume, together with its companion volume “Human Biomonitoring II: Levels and Toxicokinetics of Environmental and Industrial Chemicals in Blood, Urine and Breast Milk ”, provides a thorough overview of the presence of chemicals in human samples, including blood, urine, and breast milk. The chapters in this book cover a wide range of substances, including volatile organic compounds, food-processing induced chemicals, plasticizers, personal care and consumer product chemicals, mycotoxins, and chemicals linked to smoking, vaping, and cannabis use. Each chapter provides a toxicological perspective, detailing the chemical and physical properties, usage patterns, and biological behavior of these substances in human matrices. Together with its companion volume, both books are essential resources for researchers, scholars, and professionals in environmental health, toxicology, public health, and regulatory science. With extensive tables, figures, and reference data, both books support informed decision-making and provide practical insights into risk assessment and chemical safety in everyday life.