title: Multi-level stressor analysis from the DNA/biochemical level to community levels in an urban stream and integrative health response (IHR) assessments.
abstract: The objectives of this study were to identify multi-level stressors at the DNA/biochemical level to the community level in fish in an urban stream and to develop an integrative health response (IHR) model for ecological health diagnosis. A pristine control site (S (c) ) and an impacted site (S (i) ) were selected from among seven pre-screened sites studied over seven years. Various chemical analyses indicated that nutrient enrichment (Nitrogen, Phosphorus) and organic pollution were significantly greater (t > 8.783, p < 0.01) at the S (i)  site compared to the S (c)  site. Single-cell gel electrophoresis (comet assays) of DNA-level impairment indicated significantly (t = 5.678, p < 0.01) greater tail intensity, expressed as % tail-DNA, at the S (i)  site and genotoxic responses were detected in the downstream reach. Ethoxyresorufin-O-deethylase (EROD) assays, as a physiological bioindicator, were 2.8-fold higher (p < 0.05, NK-test after ANOVA) at the S (i)  site. Tissue analysis using a necropsy-based health assessment index (NHAI) showed distinct internal organ disorders in three tissues, i.e., liver, kidney, and gill, at the S (i)  site. Population-level analysis using the sentinel species Zacco platypus showed that the regression coefficient (b) was 3.012 for the S (i)  site and 2.915 for the S (c)  site, indicating population skewness in the downstream reach. Community-level health was impaired at the S (i)  site based on an index of biological integrity (IBI), and physical habitat modifications were identified by a qualitative habitat evaluation index (QHEI). Overall, the model values for the integrative health response (IHR), developed using the star plot approach, were 3.22 (80.5%) at the S (c)  site and 0.74 (18.5%) at the S (i)  site, indicating that, overall, ecological health impairments were evident in the urban reach. Our study was based on multi-level approaches using biological organization and the results suggest that there is a pivotal point of linkage between mechanistic understanding and real ecological consequences of environmental stressors.
authors.affiliation: Department of Biological Science, College of Biological Sciences and Biotechnology, Chungnam National University, Daejeon, Korea.
authors.forename: Jae Hoon
authors.initials: JH
authors.lastname: Lee
authors.forename: Joon Ha
authors.initials: JH
authors.lastname: Kim
authors.forename: Hee-Mock
authors.initials: HM
authors.lastname: Oh
authors.forename: Kwang-Guk
authors.initials: KG
authors.lastname: An
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D015415:Biomarkers / Q000378:metabolism; D058448:Biota; D020552:Comet Assay; D003530:Cyprinidae / Q000254:growth & development / Q000378:metabolism*; D019363:Cytochrome P-450 CYP1A1 / Q000378:metabolism; D004249:DNA Damage; D004781:Environmental Exposure; D004784:Environmental Monitoring / Q000379:methods*; D005260:Female; D005399:Fishes; D016166:Free Radical Scavengers / Q000378:metabolism; D008954:Models, Biological; D056910:Republic of Korea; D045483:Rivers / Q000737:chemistry*; D012621:Seasons; D014018:Tissue Distribution / Q000187:drug effects; D014874:Water Pollutants, Chemical / Q000378:metabolism / Q000633:toxicity*; D014877:Water Pollution, Chemical / Q000517:prevention & control; D060753:Water Quality
chemical_list: D015415:Biomarkers; D016166:Free Radical Scavengers; D014874:Water Pollutants, Chemical; D019363:Cytochrome P-450 CYP1A1