Cadmium in the purpleback flying squid Sthenoteuthis oualaniensis (Lesson, 1830) along northwest coast of India

Abstract

The purpleback flying squid Sthenoteuthis oualaniensis (Lesson, 1830) is landed in small quantities along the northwest coast of India. Keeping in view the possibility of utilization of this species for domestic and export markets, the cadmium accumulation in the body tissues, which often causes concern, was studied. The dorsal mantle length of male and female observed during the study ranged from 34 to 47 cm and 30 to 32 cm respectively. The highest mean concentration of 435.22 ± 61.27 µg g-1 (mean ± S.E.) of Cd was found in the liver. Accumulation of Cd was also prominent in the gut, gills and skin. Moderate concentration of Cd (1 to 4 µg g-1) was observed in the nidamental gland, accessory nidamental gland, eyes, tentacles and muscle. In the gonads and arms, the concentration was below the acceptability level of 1.0 µg g-1. Higher accumulation in most of the organs/tissues of larger squids was observed. Significantly higher accumulation (p < 0.05) was noticed in the liver of larger specimens, indicating bioaccumulation. As the mean Cd content in the edible part was more than 1.0 µg g-1, this study highlights the need for detailed investigations to understand the bioaccumulation of Cd in Sthenoteuthis oualaniensis