Biological response of natural populations of the lobster Nephrops norvegicus (Linnaeus, 1758), in the northern Adriatic sea to toxic metals

Biološki odgovor prirodnih populacija sjevernojadranskog škampa Nephrops norvegicus na akumulirane teške metale (arsen, krom, mangan, kadmij, olovo, živa) istraživan je na 144 jedinke oba spola u 3 veličinske kategorije i 6 organa, na dvije lokacije i sezone. Akumulacija metala ovisi o samom metalu te je tkivno i veličinski specifična te ovisi o sezoni i lokaciji. Sadržaj metalotioneina i reaktivnih kisikovih vrsta mora prelaziti graničnu vrijednost (200 µg/g metalotioneina, 40 µM/mg ROS) u više od 15% istraživane populacije ukoliko se želi utvrditi prisustvo zagađenja. Aktivnost acetilkolinesteraze mora biti manja od granične vrijednosti (1.8 nmol/min/mg proteina). Povećan je rizik od izloženosti škampa arsenu i živi zbog njegove velike akumulacijske sposobnosti ta dva metala. Preporuča se praćenje količine arsena i žive u konzumnim jedinkama. Osnovna razina žive u prirodnoj, zdravoj populaciji škampa prelazi dozvoljenu količinu (PTWI/WHO, 2007). Međutim, konzumiranjem 10 škampa tjedno ukupan unos žive u ljudski organizam ne predstavlja rizik za konzumenta.In this study the biological response to bioaccumulated heavy metals (arsenic, chromium, manganese, cadmium, lead, mercury) has been investigated in the population of shrimp Nephrops norvegicus sampled from a pristine site. Data were collected from 144 specimens of both sexes and induced 3 shrimp sizes. The biological response has been investigated in 6 organs. Shrimps were collected at two location during two seasons. Metal accumulation is tissue and size specific depending on metal itself, season and location. In order to assess the pollution metallothionein and reactive oxygen species content should be above limits of 200 µg/g and 40 µm/mg ROS respectively, in more than 15% investigated population. Acetylcholinesterase activity should be less than 1,8 nmol/min/mg prot. Accumulation capacity for arsenic and mercury increase risk to shrimp and continuous monitoring is recommended. Mercury baseline in natural shrimp population is above recommended value (PTWI/WHO, 2007). However, consummation of 10 shrimps per meal is bellow provisional tolerable weekly intake