Chromium behavior in a highly urbanized coastal area (Bahía Blanca Estuary, Argentina)

The contamination of estuaries by heavy metals from anthropogenic activities in the industrial, domestic, and agricultural sectors is a global concern. In this study, the Cr, Fe, and Mn levels in the suspended particulate matter (SPM) were analyzed in estuarine waters from Bahia Blanca Estuary, during 2014-2015. The values of particulate Cr ranged from 7.33 to 35.20 μg g^-1, which could be associated to several anthropogenic sources. The positive correlations found between Cr and Chlorophyll-a, and Cr and particulate organic carbon (POC) suggest the strong influence of phytoplankton on the adsorption of this metal and on the increase of particulate Cr. Negative correlations were found between Cr and DO and between Cr and pH, which could indicate an increasing trend in the dissolved form of Cr. This study suggests that the physical-chemical characteristics of the water column as well as phytoplankton and POC dynamics influence the behavior of Cr in this estuary.