Giftighet

Giftighet, or toxicity, is the property of a substance to cause harm to living organisms. It covers acute effects such as illness or death and chronic effects such as organ damage or cancer. The level of giftighet depends on the dose, route of exposure, duration, the species involved, and individual susceptibility.

Toxicity is evaluated through toxicology. Key concepts include the LD50, the dose or concentration that kills 50% of exposed individuals, and NOAEL or LOAEL, which indicate no observed or lowest observed adverse effects. Risk is understood as a function of both hazard and exposure, and regulatory frameworks use these concepts to set safety limits.

Types of toxicity include acute and chronic toxicity, systemic toxicity, and organ-specific toxicity. Ecotoxicity considers effects on non-human organisms in the environment. The dose–response relationship describes how increasing exposure generally increases the likelihood or severity of harm, though some substances exhibit thresholds below which no adverse effects are observed.

Factors influencing giftighet include the exposure route (inhalation, ingestion, dermal contact), frequency and duration of exposure, chemical form and bioavailability, metabolism and detoxification capacity, age and health status, genetics, and interactions with other chemicals.

Regulation and safety aim to protect people and ecosystems. Safety measures include hazard communication, labeling, and safety data sheets; exposure controls, personal protective equipment, and proper storage and handling. Environmental protection considers ecological toxicity and persistence, with monitoring to prevent harmful releases and manage risks.