Toksinosti

Toksinosti, or toxicity, is the degree to which a substance can cause harm to living organisms. It covers the adverse effects produced by chemicals, biological toxins, and physical agents such as radiation. Toxicity depends on the dose and duration of exposure, the route by which exposure occurs (inhalation, ingestion, dermal contact), and the characteristics of the organism, including age, sex, genetics, and health status. The dose–response relationship is central to toxicology and is often summarized in dose–response curves. Acute toxicity refers to harmful effects that follow a single exposure, while chronic toxicity results from repeated exposures over longer periods.

Toxicity is assessed using various metrics. LD50 and LC50 indicate the dose or concentration that kills 50% of a test population, under specific conditions. NOAEL (no observed adverse effect level) and LOAEL (lowest observed adverse effect level) are used to gauge safe exposure ranges. Toxic effects may be systemic, affecting multiple organ systems, or organ-specific, such as hepatotoxicity (liver), nephrotoxicity (kidneys), neurotoxicity (nervous system), cardiotoxicity (heart), or cytotoxicity (cell damage). Mechanisms of action include receptor interaction, enzyme inhibition, oxidative stress, and disruption of cellular processes.

Regulation and safety rely on risk assessment, including hazard identification, dose–response assessment, exposure assessment, and risk characterization. Regulatory frameworks establish exposure limits for workers and the public, promote safer alternatives, and monitor environmental concentrations. Management of toxicity emphasizes exposure reduction, medical treatment, and, where available, antidotes. Examples of toxic substances range across chemicals, metals, and biological toxins, underscoring the diverse nature of toxinosti in health and environment.