Potential environmental implications of emerging organic contaminants in Taihu Lake, China: Comparison of two ecotoxicological assessment approaches

- Most water areas were at significant risk for adverse effects based on HQ indexes.
- Compounds were ranked and hormones were regarded as the greatest hazards.
- The firstly applied EIBR in field suggested Zhushan Bays as the most stressful place.
- Both approaches, HQ and EIBR, are mutually consistent, with good positive linear correlation.

In this study, the hazard quotient (HQ) and a novel enhanced integrated biomarker response (EIBR) were applied to indirectly/directly estimate the ecotoxicological risk of emerging organic contaminants in Taihu Lake. Nine out of sixteen target compounds were detected in most sampling points at comparable concentrations (1.58-206.95 ng/L). Simultaneously, changes in multi-biomarkers were measured in caged fish for 28 days. The 0HQ results preliminarily indicated that most water areas were at significant risk for adverse effects to aquatic organisms (HQ > 10). The prioritisation was then ranked and 17α-ethinylestradiol, diethylstilbestrol and 17β-estradiol were regarded as the greatest hazards. The EIBR, covering multi-biomarkers and their weighting, was applied to field study, and Zhushan Bay was suggested as the most stressful place, followed by Meiliang Bay. The HQ showed significant positive linear correlation with the EIBR (r = 0.848, P < 0.001), suggesting mutual consistency between the two approaches based on laboratory and field study in ecotoxicological risk assessment.