Gross Anatomical Based Ecotoxicolgy: Evaluation of the Ecological Health Status of Bodo River, Using the Condition Factor and Health Assessment Index of Tympanotanus fuscatus

This ecotoxicological study is aimed to evaluate the ecological health status of Bodo River using Tympanotonus fuscatus as a biomarker. The study complements chemical environmental monitoring with bio-indicator based bio-monitoring to achieve a more holistic ecological health assessment. Based on literature review on hazardous chemical crude oil spill, the following Target Chemicals (TCs) where selected for the study: lead (Pb), cadmium (Cd), chromium (Cr), copper (Cu), nickel (Ni) and polyaromatic hydrocarbon (PAH). The experimental study area was Bodo River, while African Regional Aquaculture Centre (ARAC) was selected as the references site. In both sites, water, sediment and T. fuscatus were sampled for a comparative study. Water and sediment samples were used to evaluate Environmental Water Quality Index (EWQI) and sediment quality respectively. The sampled fish was used for gross anatomical assessment of condition factor (CF) and Health Assessment Index (HAI). EWQI of Creek Road River results showed worse outcome than ARAC, with dissolved oxygen (DO) and copper (Cu) failed to meet the Maximum Allowable Toxicant Concentration (MATC) guideline for marine water. Sediment quality showed that worse outcomes in ARAC, but with Bodo River having a high Ni value above the MATC for marine sediment in Bodo River. There was no significant difference in CF and HAI for experimental and reference sites. The study was able to show that there was an ongoing Cu contamination of Bodo River with resultant reduction in DO and a historic spectrum of Ni contamination profile. The CF and HAI results showed a good ecological health status of the river. Though, the finding was inconsistent with the expected environmental impact from the water and sediment quality results. It was therefore concluded that a more ecological health sensitive test tool is needed to make a more assertive statement on the ecological health status of Bodo River.