Evaluation of surface water and sediment quality in Chicalim Bay, Nerul Creek, and Chapora Bay from Goa coast, India—a statistical approach

To better understand the spatial and temporal variation in surface water and sediment quality, parameters were evaluated from the three sites Chicalim Bay (CB), Nerul Creek (NC), and Chapora Bay (ChB) along the Goa coast, which has major oyster beds. Multivariate analysis such as cluster analysis (CA), Box–Whisker plot (Box plot), and principle component analysis (PCA) revealed that nitrate (NO 3 –N), nitrite (NO 2 –N), phosphate (PO 4 –P), particulate organic carbon (POC), total suspended solids (TSS), dissolved oxygen (DO), and phaeopigments are the responsible parameters for spatio-temporal variability among the studied sites. Results showed an elevated level of ecotoxicological hazard at CB while moderate toxicological risks were observed for organisms at NC. In contrast, ChB was considerably pristine compared with other two sampling sites. Results of present study showed marked dominance of nutrients, phaeopigments, POC, and TSS at CB and NC. The increased levels of these parameters are attributed to the anthropogenic activities which may cause potential risk to humans via consumption of oysters. Therefore, we suggest monitoring heavy metal concentrations in tissue of commercially important oyster species, and their ambient environment (water and sediment) from these estuaries is necessary to create a comprehensive pollution database.