| Popis: |
Carryover toxicity (CT) goes uneliminated or is added by a technology. Current and emerging wastewater technologies are not being tested for CT. A new test based on four (EPA-OECD harmonized) bioassays was probed here on hospital wastewater (HWW) using three wastewater technologies. Real-life and experimental complexity (technologies, xenobiotics, trophic, endpoints), as well as ill-suited usual metrics warranted the use of dimension reduction tools for data analysis. The results pointed to fat, oil and grease (FOG) associated to total P as clear predictors of induction, related to EDs and pharmaceuticals. Inhibition was related to high COD, especially in the cases of zeolite with hexadecyltrimethylammonium bromide (HDTMA), and chlorination. Data analysis hinged on the dose-response curve knee (well correlated with entropy). Sensitivity and specificity of the 3-taxa test were high. A combined assessment of the toxicological costs of HWW treatment technologies showed that the effect of Ze+HDTMA on D. pulex was the highest cost. Interestingly, the knee highlighted a saturation pattern common to all the bioassays; it was posited to be due to the number of hormone receptor proteins (likely highly conserved through evolution). |
