Heavy metals remain pervasive environmental stressors, yet comparative hazard ranking often relies on single-point metrics (e.g., EC 50 ) and limited test species, potentially obscuring concentration–response (C–R) shape information and cross-trophic variability. Here, acute C–R relationships for ten metals were quantified across four organisms representing distinct trophic levels ( Danio rerio, Daphnia magna, Aliivibrio fischeri, and Scenedesmus obliquus ). Probit regression was used to derive multi-point effect concentrations (EC 10 –EC 100 ) and characterize curve-shape differences. An entropy weight method was then applied to objectively weight ECx information within species and integrate evidence across species to construct a Comprehensive Bio-toxicity Index (CBTI). Marked interspecific variability was observed, with metal rankings differing substantially among taxa and with EC 90 /EC 10 ratios indicating notable differences in curve steepness. The CBTI yielded a multi-trophic hazard hierarchy in which HgCl 2 showed the highest aggregate toxicity (94.41), followed by ZnSO 4 (84.56) and Pb(NO 3 ) 2 (78.22), while Na 2 MoO 4 was least hazardous (24.59). These findings support curve-aware, entropy-weighted multi-trophic integration as a transparent bridge between single-endpoint testing and holistic ecotoxicity evaluation.
Guo et al. (Wed,) studied this question.