haitalliset

Haitalliset is a Finnish adjective meaning harmful or detrimental. It is formed from the noun haitta, meaning harm or nuisance, with the common adjectival suffix -llinen, giving haitallinen for the singular and haitalliset for the nominative plural. In Finnish, adjectives agree with the noun in number and case, so haitallinen becomes haitalliset when describing plural nouns, for example haitallinen vaikutus (a harmful effect) and haitalliset vaikutukset (harmful effects).

The term is widely used in health, safety, and environmental contexts. Common phrases include haitalliset aineet (harmful or hazardous substances), haitalliset vaikutukset (harmful effects), and haitalliset käytännöt (harmful practices). It can also describe behaviors, habits, or trends that cause damage over time. In everyday language, haitalliset often appears in discussions about public health, consumer information, and risk communication.

Nuance and relation to other terms: haitallinen contrasts with vaarallinen. While vaarallinen typically signals immediate danger or threat, haitallinen emphasizes harm that may be long-term, cumulative, or not immediately obvious. The noun form haitallisuus refers to the property or quality of being harmful.

See also: haitta, haitallisuus, haitallinen. The term is part of general Finnish descriptive vocabulary and is used across formal and informal discourse to characterize phenomena that cause damage or negative health or environmental outcomes.