Title Određivanje esencijalnih metala u tkivima kitova zubana (Odontoceti) iz Jadranskog mora Title (english) Determination of essential element levels in tissues of toothed whale (Odontoceti) from the Adriatic Sea Author Maja Đokić Mentor Tomislav Bolanča (mentor)Mentor Nina Bilandžić (mentor)Committee member Marko Rogošić (predsjednik povjerenstva)Committee member Šime Ukić (član povjerenstva)Committee member Tomislav Gomerčić (član povjerenstva)Granter University of Zagreb Defense date and country 2017-12-08, Croatia Scientific / art field, NATURAL SCIENCES Universal decimal classificationUDC ) 54 - Chemistry. Crystallography. Mineralogy Abstract U morski okoliš elementi dospijevaju iz prirodnih i antropogenih izvora. Morski sisavci akumuliraju ih u tkivima uglavnom prehranom, a njihova bioakumulacija ovisi o vrsti sisavca, samom elementu i karakteristikama tkiva. U ovom istraživanju određivane su koncentracije esencijalnih elemenata u tragovima u tkivima jedinki tri vrste kitova zubana (Odontoceti), dobrom (Tursiops truncatus), plavobijelom (Stenella coeruleoalba) i glavatom dupinu (Grampus griseus). S obzirom na to da u literaturi nedostaju podaci o koncentraciji esencijalnih metala u tkivima dupina, određena je povezanost koncentracija esencijalnih metala s vrstom tkiva, duljinom tijela, starošću, vrstom dupina, spolom i lokacijom pronalaska lešine. Određen je fiziološki raspon elemenata, a povećane razine određenog elementa omogućile su procjenu uzročnika zagađenja na određenom području, odnosno razmatranje eventualnih izvora ljudske djelatnosti koja upućuju na prekomjerno korištenje ovog elementa i njegovo širenje u morski sustav. Istraživanje obuhvaća 190 dupina, od toga 159 dobrih,
25 plavobijelih i 6 glavatih dupina koji su pronađeni u hrvatskom dijelu Jadranskog mora u razdoblju od 1995. do 2013. godine. Esencijalni elementi kobalt, krom, bakar, mangan i cink određivani su u tkivima jetre, mišića, bubrega, kože, pluća, slezene i masnog tkiva primjenom induktivno spregnute plazme – optičko emisijske spektrometrije (ICP-OES). U više od 50 % ispitivanih tkiva koncentracija kobalta iznosila je 0,001 mg/kg u sve tri vrste dupina. Koncentracija kroma veća od 1 mg/kg određena je u samo 16 uzoraka tkiva. Od toga 15 je pripadalo dobrom dupinu, a samo jedno tkivo plavobijelom dupinu. Koncentracije mangana u svim ispitivanim tkivima tri vrste dupina su u očekivanom rasponu za morske sisavce, odnosno manje od 7 mg/kg mokre težine. Koncentracije i bakra i cinka izvan kritičnih homeostazom kontroliranih raspona (bakar 3 – 30 mg/kg; cink 20 – 100 mg/kg) u jetri određene su u 16 jedinki, odnosno u 14 dobrih dupina te dvije jedinke plavobijelih dupina.
U glavatih dupina nisu utvrđena odstupanja od kritičnih raspona cinka i bakra u jetri. Od 16 jedinki dupina za 12 su koncentracije bakra i cinka iznad gornjih kritičnih koncentracija.
S obzirom na geografski položaj pronalaska, svih 12 jedinki pronađeno je na južnom dijelu hrvatskog dijela Jadrana. Pretpostavka je da su povišene koncentracije bakra i cinka u jetri posljedica onečišćenja morskog okoliša, u ovome slučaju Jadrana. Utvrđene su statistički značajne pozitivne korelacije između koncentracija pojedinih elemenata u tkivima mišića, jetre i bubrega. Negativna korelacija slabog intenziteta određena je za koncentracije kobalta i bakra u mišiću dupina. Najjače pozitivne korelacije utvrđene su između bakra i cinka u tkivima jetre i bubrega. Ovo upućuje na zaključak da je njihova uloga u formiranju i funkciji enzima ključnih za metabolizam organizama sinergistična, a ne antagonistična kao što je opisano u literaturi. Dobiveni rezultati su prva značajna studija raspona koncentracija ovih elemenata u tri populacije dupina Jadranskog mora tijekom dva desetljeća te mogu budućim istraživanjima dati nove smjernice za očuvanje populacije dupina u hrvatskom dijelu Jadranskog mora.
Abstract (english) In the marine environment, elements originate from natural and anthropogenic sources. Marine mammals accumulate elements in tissues mainly via the diet, and their bioaccumulation depends on the species, the element and the characteristics of the tissue. The aim of this study was to determine the concentrations of essential trace elements in the tissues of three species of toothed whales (Odontoceti): bottlenose (Tursiops truncatus), striped (Stenella coeruleoalba) and Risso’s (Grampus griseus) dolphins. There is little data on the concentrations of essential metals in dolphin tissues. In this study, essential metal concentrations were correlated with tissue type, body length, age, dolphin species, sex and location of finding the carcasses. Also, the physiological range of elements was determined. Increased levels of certain elements allowed for the assessment of causes of pollution in a given area or determination of possible source of human activity that indicated the excessive use of this element and its expansion into the marine system. The study examined a total of 190 dolphins: 159 bottlenose, 25 striped and 6 Risso's dolphins found in the Croatian part of the Adriatic Sea in the period from 1995 to 2013. The essential elements cobalt, chromium, copper, manganese and zinc were determined in the liver, muscle, kidney, skin, lung, spleen and adipose tissues using inductively coupled plasma–optical emission spectrometry
(ICP-OES). In more than 50 % of the examined tissues, the cobalt concentration was
0.001 mg/kg in all three dolphin species. Chromium concentrations greater than 1 mg/kg were determined in only 16 tissue samples. Of these, 15 were bottlenose dolphins, and only one was striped dolphin. Manganese concentrations in all examined tissues of three dolphin species were in the expected range for marine mammals, less than 7 mg/kg wet weight. The concentrations of copper and zinc outside the critical homeostasis controlled ranges
(copper 3–30 mg/kg, zinc 20–100 mg/kg) in the liver were determined in 16 individuals,
(14 bottlenose and 2 striped dolphins). There were no deviations from the critical zinc and copper ranges in the liver of the Risso’s dolphins. Among 16 dolphins outside the critical homeostasis controlled ranges, 12 had concentrations of copper and zinc above the critical concentrations, all of which had been found in the southern part of Croatian waters of Adriatic Sea. The assumption is that elevated concentrations of copper and zinc in the liver are the result of pollution of the marine environment, in this case the Adriatic Sea. Statistically significant positive correlations were found between element concentrations in muscle, liver and kidney tissues. A slight negative correlation was determined for cobalt and copper concentrations in muscle. The strongest correlations were found between copper and zinc in liver and kidney. This suggests that their role in the formation and function of the key enzymes for metabolism is synergistic rather than antagonistic as described in the literature. The obtained results are the first significant study of the concentration ranges of these elements in the three dolphin species of the Adriatic Sea over two decades. The results may provide directions for future research and new guidelines for preserving the dolphin population in the Croatian part of the Adriatic Sea.
Keywords
esencijalni metali
dupini
tkiva
Jadransko more
Keywords (english)
essential metals
dolphins
tissues
Adriatic Sea
Language croatian URN:NBN urn:nbn:hr:149:932864 Promotion 2017 Project Number: 053-0533406-3640 Study programme Title: Engineering Chemistry - Doctoral Course Type of resource Text Extent 178 str. ; 30 cm File origin Born digital Access conditions Open access Terms of use Created on 2023-12-06 11:10:48
