Abstract: Ubiquitous chemical pollutants, including heavy metals, phthalates, bisphenols, pesticides, and polycyclic aromatic hydrocarbons (PAHs), are widely present in aquatic environments in China, posing potential risks to ecosystem health. To enable a comparative risk ranking of these diverse contaminants, this study selected eight representative substances: chromium (VI), lead (II), cadmium (II), dibutyl phthalate (DBP), di(2-ethylhexyl) phthalate (DEHP), bisphenol A (BPA), deltamethrin (DM), and benzoapyrene (BaP). A multi-tiered toxicity evaluation was performed, including acute assays (luminescent bacteria Photobacterium phosphoreum and water flea Daphnia magna), a zebrafish embryo developmental toxicity test, and larval locomotor behavior analysis. The test organisms exhibited distinct sensitivity spectra: P. phosphoreum to \textPb^2+ , DM, BaP, and \textCd^2+ ; D. magna to DM and \textCd^2+ ; and zebrafish embryos to DM, DBP, \textCd^2+ , and BaP. All compounds showed time-dependent increases in toxicity ( \textEC_50 / \textLC_50 ). The rank order of developmental toxicity in embryos (DM > DBP > \textCd^2+ > BaP > BPA > \textCr^6+ > \textPb^2+ > DEHP) aligned with their 96h- \textLC_50 values. Critically, behavioral analysis uncovered a class-divergent neurobehavioral response: sublethal exposure to heavy metals ( \textCr^6+ , \textCd^2+ , \textPb^2+ ) elicited larval hyperactivity, in contrast to the hypoactivity induced by organic pollutants (DEHP, BPA, DM, BaP). Through its multi-species, multi-endpoint approach, this study not only pinpointed DM, C \textCd^2+ , and DBP as high-risk pollutants but also established a critical data foundation for ecological risk ranking and prioritization of typical contaminants in China’s aquatic environments. Moreover, the distinct, class-specific opposite behavioral phenotypes uncovered herein represent potential sensitive biomarkers for pollutant-type discrimination and early-warning monitoring.