Changes in the tissue concentrations of trace elements during the reproductive cycle of Noah's Ark shells (Arca noae Linnaeus, 1758)

Concentrations of 23 trace elements (TEs; essential: Co, Cu, Fe, Mn, Mo, Se, V, Zn; non-essential: Ag, Al, As, Ba, Cd, Cr, Cs, Li, Ni, Pb, Rb, Sr, Ti, Tl, U) in whole soft tissues of Noah's Ark shell (Arca noae) were determined monthly during one year (March 2013–February 2014) at two sampling sites in the central part of the Eastern Adriatic Sea. Our aim was to detect the influence of reproductive cycle and changes in the environmental factors on the variabilities of TEs' contents. Higher concentrations of Pb, Ba, V, Mo, Mn and Fe were found at potentially contaminated site in Pašman channel, whereas higher concentrations of Tl, Ni, Li, Cr, Cd, Ti and Se were found at reference site in Nature Park Telašćica. Since several bioaccumulated TEs were associated to mean gonadal index, in TEs monitoring in A. noae, animal gonadal status has to be considered. •23 trace elements in soft tissues of Arca noae determined monthly during one year•Bioaccumulated trace elements were associated to mean gonadal index (MGI).•Cd, Co, Fe, Mn, Li and Se - significant negative association to MGI at reference site•Ba, Li, Mn and V - significant negative association to MGI at exposed sampling site•Significant positive associations: Rb, Zn at reference site; Rb, Tl at exposed site