Shrimp tissue quality in the lower Gangetic delta at the apex of Bay of Bengal

Abstract

Seafood containing elevated levels of metals as a result of environmental contamination may entail health risks to human beings. To evaluate such contaminations, our study targeted on the analyses of lead and cadmium, in addition to the toxicologically less-relevant metals, zinc and copper, in the muscle tissue of five commonly edible shrimp species collected from the lower stretch of the River Ganga (in the Sundarbans delta complex). The metals in the tissue samples were determined using an inductively coupled plasma-mass spectrometer. The concentrations in the shrimps ranged as follows: Pb: from below detection limit to 15.9 ± 0.8 ppm dry weight; Cd: from below detection limit to 7.3 ± 0.8 ppm dry weight; Zn: 13.0 ± 0.7–428 ± 3 ppm dry weight; Cu: 8.5 ± 0.3–146 ± 3 ppm dry weight. The concentrations of the metals in the tissues varied significantly depending upon the locations from where the shrimp species were collected. The levels of Pb, Cd, and Cu in shrimp muscle at station 1 were far above the permissible levels for human consumption, while the concentration of Zn was within the normal range at all stations. Station 1 is subjected to maximum stress in terms of pollution, being situated downstream of the River Ganga.