altistuja

Altistuja is an Estonian noun meaning a person who is exposed to something—such as a hazard, stimulus, or agent. It is formed from the verb altistuma (to be exposed) with the agent-noun suffix -uja, and the related noun altistumine denotes the exposure itself. The term emphasizes the experiencer of exposure rather than the source of exposure.

In practice, altistuja is used across scientific, medical, and occupational contexts. In clinical research and pharmacology, an altistuja is a participant who is subjected to a treatment, drug, or other intervention. In environmental health and radiation protection, residents or workers who are exposed to pollutants, radiation, or other hazards may be described as altistujad (plural). The concept helps distinguish the person experiencing exposure from the source of exposure.

Ethical and regulatory considerations accompany the use of the term. Studies involving altistujad require informed consent, risk assessment, and monitoring. Exposure levels should be minimized and kept within approved limits, and data about participants are protected under privacy and ethical guidelines. Responsibility for safe exposure practices lies with researchers, institutions, and relevant regulatory bodies.

See also: altistumine, altistaja, and related terms for exposure in Estonian. The term is primarily descriptive and neutral, used to identify the person who is subject to exposure in a given context.