Evaluation of water quality and bioaccumulation of metals in commercially important fishes: a human health concern.

Abstract

The present study aimed to determine the physicochemical properties of the coastal water and metal concentration in the muscle tissues of five commercially important fish species (Leiognathus equulus, Lates calcarifer, Sillago sihama, Scolopsis bimaculatus, Lutjanus fulviflamma) along Thondi coast, as well as the potential human health risks on consumption of these species were also studied. Water quality parameters, such as mean temperature (31.3 ± 1.86°C), salinity (28.35 ± 0.79‰), pH (7.95 ± 0.22), TDS (12840 ± 1.49mgL-1), TSS (310 ± 0.51mgL-1) and DO (5.99 ± 0.14mgL-1) were obtained. Various nutrients such as calcium (300.0 ± 36.05mgL-1), inorganic phosphate (0.186 ± 0.02μgL-1), magnesium (1077.6 ± 107.01mgL-1), nitrate (1.584 ± 0.31μgL-1), nitrite (1.179 ± 0.34μgL-1), silicate (29.717 ± 1.93μgL-1) and total phosphorus (0.153 ± 0.08μgL-1) were also analysed. The concentration of metals As, Cd, Cr, Cu, Pb and Zn in the muscle tissue was determined using atomic absorption spectroscopy (AAS). Arsenic, Cu and Pb were found to be highest in S. sihama; 1.2364 ± 0.12, 1.6102 ± 0.28 and 1.0103 ± 0.21μg/g respectively. Cadmium and Zn were found maximum in S. bimaculatus; 0.0876 ± 0.04 and 1.0564 ± 0.16μg/g respectively, whereas Cr was found highest in L. Calcarifer; 1.6781 ± 0.18μg/g. Compared our results with FAO/WHO/EU regulations. The estimated daily intake (EDI) specifies that there is no risk of consuming these species. However, the target hazard quotient (THQ) in As is found to be > 1 in these fish species, which implies a possible danger to consumers.