Distribution and ecological- and health-risk assessment of heavy metals in the seawater of the southeast coast of India.

The objective of the present study was to conduct an ecological and health risk assessment of heavy metals in the seawater of the southeast coast of India. The distribution profile of heavy metals in the surface seawater was Fe (79.60 ± 21.57 µg/L) > Zn (9.31 ± 1.33 µg/L) > Cu (5.19 ± 2.00 µg/L) > Ni (2.45 ± 0.76 µg/L) > Mn (1.20 ± 1.00 µg/L) > U (0.44 ± 0.23 µg/L) > Pb (0.36 ± 0.06 µg/L) > Cr (0.31 ± 0.57 µg/L) > Cd (0.11 ± 0.05 µg/L) > Co (0.07 ± 0.20 µg/L). Cu level for most of the samples exceeded the USEPA criteria for acute CMC (criterion maximum concentration) and chronic CCC (criterion continuous concentration). Other studied metals, Cd, Cr, Pb, and Ni, remained below the acute CMC and chronic CCC guidelines. The seawater pollution index (Iwp) of Cr, Ni, Zn, Cd, and Pb complied with the category-I seawater (<1, unpolluted). The ERI values (0.46-3.99) of the seawater of the studied coast mostly fell under the ecologically low risk category with respect to heavy metals. Dermal Hazard index values were orders of magnitude lower than one, indicating no potential health concern due to dermal exposure.

Elemental distribution and trace metal contamination in the surface sediment of south east coast of India.

Spatial distribution and potential ecological risk of trace metals in the surface sediment of south east coast of India covering eight different ecosystems was studied. The concentration of major elements viz. Ca, Mg, K, Ti and trace metals viz. Cr, Mn, Co, Al, Fe, Ni, Cu, Zn, Cd and Pb were analysed by energy dispersive X-ray fluorescence technique. Contamination factor, geo-accumulation index, probable effect level, enrichment factor and pollution load index were calculated to evaluate the pollution status. Except cadmium, CF values for all the metals ranged between 1≤CF≤3 indicating moderate metal contaminations along the coast. Mean PEL quotient (Qm-PEL) indicated toxicity probability to be below 21%. Fe, Cu, Zn and Co showed significant positive correlation (p<0.01) with clay. Chromium was the only metal that demonstrated strong negative correlation with clay (p<0.01) and positive correlation (p<0.01) with sand content.