Trace element concentrations in the Mediterranean monk seal (Monachus monachus) in the eastern Mediterranean Sea.
The Mediterranean monk seal (Monachus monachus) is one of the most endangered marine mammals in the world. The biggest sub-population of the species survives in Greece, where understanding the effects of pollution on the survival of the species has been identified as a national research and conservation priority. From 1990 to 2013 we collected tissue samples from 59 deceased monk seals in order to: (i) Define the concentration of trace elements (As, Pb, Cd, Hg, Se, Cr, Ni) in three different matrices (i.e., blubber, liver and kidney), (ii) Determine whether differences in trace element concentrations are age- or gender-related, (iii) Evaluate the potential effects of these pollutants. The study recorded differences in trace element concentrations among matrices, but in general, trace element exposure in Mediterranean monk seals in Greece was low and within the non-acutely toxic levels for Pinnipeds. Only arsenic concentrations were at the upper limit of the normal range observed in other marine mammals (0.69±0.55mg/kg w.w. in blubber, 0.79±0.62mg/kg w.w. in liver and 0.79±0.59mg/kg w.w. in kidney). We recorded also exceptionally high Hg concentrations in a single adult female (24.88mg/kg w.w.). Age- and gender-related differences were also recorded and were due to various biological, ecological and chemical factors. Based on the results of the study, potentially adverse effects on the immune and endocrine system of the Mediterranean monk seal from some pollutants (e.g., As, Cd, Se, Ni, Cr) cannot be ruled out, which may expose the Mediterranean seal population in Greece to epizootics and stochastic phenomena of mass mortality. It is therefore of utmost importance that pollutant monitoring becomes an integral component of the standard monitoring protocol of the endangered Mediterranean monk seal in the eastern Mediterranean.
Large Pelagic Vertebrate Group, Department Veterinary Medical Sciences, University of Bologna, Viale Vespucci 2, 47042 Cesenatico (FC), Italy.
Costanza
C
Formigaro
MOm/Hellenic Society for the Study and Protection of the Monk Seal, Solomou Str. 18, 10682 Athens, Greece.
Alexandros A
AA
Karamanlidis
MOm/Hellenic Society for the Study and Protection of the Monk Seal, Solomou Str. 18, 10682 Athens, Greece.
Panagiotis
P
Dendrinos
Department of Environment, Earth and Physical Sciences, University of Siena, via Mattioli 4, 53100 Siena (SI), Italy.
Letizia
L
Marsili
Large Pelagic Vertebrate Group, Department Veterinary Medical Sciences, University of Bologna, Viale Vespucci 2, 47042 Cesenatico (FC), Italy.
Marina
M
Silvi
Large Pelagic Vertebrate Group, Department Veterinary Medical Sciences, University of Bologna, Viale Vespucci 2, 47042 Cesenatico (FC), Italy. Electronic address: annalisa.zaccaroni@unibo.it.
Annalisa
A
Zaccaroni
D000273:Adipose Tissue / Q000737:chemistry; D000818:Animals; D005260:Female; D006115:Greece; D008522:Mediterranean Sea; D046048:Seals, Earless; D014131:Trace Elements / Q000032:analysis*
D014131:Trace Elements
Endangered species; Exposure; Mediterranean monk seal; Risk evaluation; Trace elements