Effects of anthropological factors on the metal accumulation profiles of sea cucumbers in near industrial and residential coastlines of İzmir, Turkey

ABSTRACT

This study details the metal and metalloid accumulation profiles of three species of sea cucumbers (Holothuriamammata, Holothuriapolii and Holothuriatubulosa) native to Aliağa and Ildır (İzmir, Turkey), two regions that are representative of industrial and residential districts, respectively. A total of 11 elements were analysed (Fe, Cu, Mn, Zn, Cr, Co, V, Ni, Cd, Pb and As) from gut and body wall tissues of holothurians and in sediment samples. The Mann–Whitney U analysis revealed statistical difference between locations and tissues. Accumulations of Aliağa samples were significantly higher than Ildır samples with respect to Zn, V, Mn, Cr, Fe and Co while accumulations were significantly higher in the gut than body wall regardless of the region for all elements tested. The correlation analysis showed more and stronger correlations in the gut than in the body wall. In addition, metal(loid) concentrations in the sediment were found to correlate strongly with these in the sea cucumber gut. The cluster analysis displayed totally different element accumulation pattern for Aliağa and Ildır in the both tissues which indicate that anthropogenic effects start to alter the bioaccumulation of metal(loids). Biota-sediment accumulation factors (BSAF) and metal contamination index were calculated to determine the extent of metal(loid) uptake and to compare total elemental accumulation at each region. Gut tissue elemental BSAF is higher than body wall for all elements at both areas. Cd has the highest value with 5.582 (gut tissue) and the lowest are Ni, V and Cr with 0.001 (body wall tissue). In addition, sediment results were compared with previous studies and sediment quality guidelines and found to exceed the lowest effect level (LEL) values for As and Ni.

KEYWORDS:

• Aegean sea
• bioaccumulation
• bioaccumulation factor
• holothuria
• multivariate analysis

Acknowledgements

This study was supported by Ordu University Research Fund [project number AR-1501] and Istanbul University Research Fund [project number 50025/2352]. We are grateful to AlperDevrim Özkan and Hüseyin Çaldirak for their support.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This study was supported by Ordu University Research Fund [project number AR-1501] and Istanbul University Research Fund [project number 50025/2352].