In Vitro Effect-Based Analysis of Stormwater Pond Sediments: Linkage to the Organic Contaminant Profile

This study investigated
the relationship between biological effects
and contamination profiles in sediments from 17 stormwater sedimentation
facilities across four Swedish municipalities. Sediment extracts were
examined using a battery of in vitro bioassays targeting
five modes of action: aryl hydrocarbon (AhR), estrogenic (ER), androgenic
(AR), antiandrogenic (AntiAR) receptors, and oxidative stress (Nrf2)
activities, along with cytotoxicity. Significant differences in biological
activities across cities aligned with patterns in previously characterized
profiles of 259 urban-sourced organic substances. Concentrations of
bioactive substances correlated positively with biological activities;
however, they explained only a limited fraction (typically <10%)
of the observed effects, suggesting the influence of unmonitored substances.
Among the examined substances, polycyclic aromatic hydrocarbons and
alkylphenols were the most prominent drivers of chemically explained
biological activities across end points. A masking effect between
AR and AntiAR was revealed, with negative correlations between AR
responses and agonist concentrations indicating dominance of antiandrogenic
activity. Cytotoxicity rankings across samples did not align with
acute toxicity previously measured on the same sediments using Microtox.
However, overall cytotoxicity correlated significantly with chemical
contamination indicators. These findings highlight the relevance of
effect-based tools in capturing mixture effects in stormwater sediments
and support their integration alongside chemical analysis in sediment
quality assessments.