Open AccessEvaluation of the Pollution Status of Lagos Coastal Waters and Sediments, using Physicochemical Characteristics, Contamination Factor, Nemerow Pollution Index, Ecological Risk and Potential Ecological Risk Index
Author(s) -
Gloria Ekaete Ajani,
Samuel Olatunde Popoola,
O. O. Oyatola
Publication year - 2021
Publication title -
international journal of environment and climate change
Language(s) - English
Resource type - Journals
ISSN - 2581-8627
DOI - 10.9734/ijecc/2021/v11i330371
Subject(s) - environmental chemistry , pollution , total dissolved solids , salinity , biochemical oxygen demand , total suspended solids , contamination , environmental science , christian ministry , chemistry , environmental engineering , chemical oxygen demand , ecology , wastewater , biology , philosophy , theology
The heavy metals and physicochemical properties of Lagos coastal waters and sediments, Southwestern Nigeria were investigated in 5 stations (station 1-5), to determine their levels, distributions and pollution index. The observed ranges of physicochemical characteristics from the study area are: dissolved oxygen (DO): 2.15-11.3 mg/L; pH: 6-7.7; temperature (Temp): 28.05-29.25°C; biochemical oxygen demand (BOD): 1.6-110.1 mg/L; electrical conductivity (EC): 1.8-29.8 mS/cm; salinity (SAL): 0.02-2.05ppt; total dissolved solids (TDS): 211.8-1210.2 mg/L and total suspended solids (TSS): 12.13-117.95 mg/L. The analyzed physicochemical properties from all the stations are within the desired values for healthy marine ecosystems when compared with Federal ministry of environment (FMENV) Nigeria and World Health organization permissible limits (DO:>5 mg/L; pH:6.5-9; TEMP: Pb > Cu > Cr > Zn > Cd, and showed high values for Pb, Cd and Cr, relative to the standard permissible limits according to FMENV (Pb 0.001; Zn 50 mg/L; Cd 6) values across the sampling stations. The calculated Nemerow pollution index (NPI) and ecological risk index (RI) showed heavily polluted (NPI > 10) values and very high ecological risk (RI > 380) values at Apapa (location 1), Iddo (location 2) and Makoko (location 3). The potential ecological risk factor (Eir) confirmed Cd as the highest polluted heavy metals (Eir >320), with the greatest potential threat to the marine ecosystems in the Lagos coastal waters. The study highlights the impacts of anthropogenic pollutions on the coastal ecosystems and human health.