4HPEA

4HPEA is an acronym encountered in several disciplines, and there is no universally accepted single definition. Its meaning depends on the field, and sources typically distinguish between chemical and planning contexts.

In chemistry and biochemistry, 4-HPEA denotes 4-hydroxyphenethylamine, a monoamine structurally related to phenethylamine. This compound is also referred to as tyramine and occurs in various foods and tissues. It acts as a trace amine and can influence neurotransmitter metabolism, especially in individuals taking monoamine oxidase inhibitors.

In environmental planning and policy discussions, 4HPEA has been used to denote a Four-Habitat Environmental Assessment framework. The concept proposes evaluating ecological and human-health impacts across four habitat domains—terrestrial, freshwater, marine, and urban. Proponents describe the framework as a way to improve consistency and comparability in impact assessments, but it has not achieved broad standardization or widespread regulatory use.

Because of its multiple meanings, the intended sense of 4HPEA must be inferred from context.