Definitions for "LOEC"
" Low Observed Effect Concentration " or concentration with a very weak observable effect. It is about the lowest concentration for which the effect is different from that of controls. It is the first concentration tested after the NOEC.
lowest observed effects concentration
(Lowest-observed-effect-concentration): The lowest concentration of an effluent or toxicant that results in adverse effects on the test organisms (i.e., where the values for the observed endpoints are statistically different from the control) (EPA, 2000).