USE OF NATURAL ZEOLITES AS A DETOXIFIER OF HEAVY METALS IN WATER AND THE FLESH OF REARED EUROPEAN SEABASS Dicentrarchus labrax

Autor: Hadir A. Aly, Mohamed M. Abdel-Rahim, Ghada R. Sallam, Ayman M. Lotfy, Basem S. Abdelaty
Jazyk: angličtina
Rok vydání: 2020
Předmět:
Zdroj: Croatian Journal of Fisheries : Ribarstvo
Volume 78
Issue 3
ISSN: 1848-0586
1330-061X
Popis: Provedeno je istraživanje kojim su se ispitivali učinci prirodnih zeolita kao pročišćivača vode na učinkovitost uklanjanja teških metala iz podzemne slane vode koja se koristi za uzgoj mlađi Dicentrarchus labrax. Ispitano je pet koncentracija zeolita: 0 (Z0), 2,5 ‰ (Z2,5), 5‰ (Z5), 7,5 ‰ (Z7,5) i 10 ‰ (Z10). Mlađ s početnom tjelesnom masom od 1,53 ± 0,018 g su nasađene u 15 akvarija s gustoćom 10 jedinki/akvarij. Ribe su se hranile komercijalnom hranom (42% proteina i 12,34% lipida) dva puta dnevno (09:30 i 14:00), u udjelu od 5% tjelesne mase ribe, tijekom 42 dana. Evaluirani su rast, iskorištavanje hrane, preživljavanje i učinkovitost uklanjanja teških metala. Indeksi rasta i iskorištenja hrane postupno su se poboljšavali s povećanjem koncentracije zeolita, pri čemu su najznačajnije vrijednosti (P≤0,05) otkrivene sa skupinom Z10. Stopa preživljavanja značajno se smanjila u skupini Z10 pri usporedbi s kontrolom (Z0). Značajno povećanje koncentracije zeolita (P≤0,05) poboljšalo je učinkovitost uklanjanja teških metala iz uzgojne vode sa adsorpcijskom selektivnošću Pb˃Cd˃Fe˃Cu˃Zn. Nadalje, otkriveno je povećanje brzine detoksikacije teških metala u mesu ribe s povećanjem razine zeolita uz selektivnost uklanjanja Fe˃Cu˃Zn˃Pb˃Cd. Zaključno, može se reći da se prirodni zeoliti mogu učinkovito koristiti za smanjenje teških metala u onečišćenim vodama, a posljedično i u mesu ribe, uz poboljšanje performansi rasta ribe.
A study was conducted to investigate the effects of natural zeolites as a water clarifier on the heavy metal removal efficiency from the underground saltwater used for rearing Dicentrarchus labrax fry. Five concentrations of zeolites were tested: 0 (Z0), 2.5‰ (Z2.5), 5‰ (Z5), 7.5‰ (Z7.5) and 10‰ (Z10). Fry with an initial body weight of 1.53±0.018 g/fish were stocked in 15 aquaria at a density of 10 fry/aquarium. The fish were fed a commercial diet (42% protein and 12.34% lipid) twice daily (09:30 and 14:00) at 5% of their body weight per day for 42 days. Growth, feed utilization, survival and heavy metal removal efficiency were evaluated. The growth performance and feed utilization indices gradually improved with increasing zeolite concentration, with the most significant (P≤0.05) values detected at Z10. The survival rate decreased significantly at Z10 compared with the control (Z0). Increasing the zeolite concentration significantly (P≤0.05) improved the removal efficiency of heavy metals in the rearing water with adsorption selectivity of Pb˃Cd˃Fe˃Cu˃Zn. Furthermore, an increase in the detoxification rate of heavy metals in fish flesh with increasing zeolite level was detected with the removal selectivity of Fe˃Cu˃Zn˃Pb˃Cd. In conclusion, it can be stated that natural zeolites can be used effectively to reduce heavy metals in polluted waters and subsequently in fish flesh in addition to improving fish performance.
Databáze: OpenAIRE