HEAVY METALS CONCENTRATION LEVELS IN SOME FISH SPECIES OF LAKE MARlUrAND THE lVOZHA HYDRODROME, EGYPT DURING 1974 MiD 1995

HEAVY METALS CONCENTRATION LEVELS IN SOME FISH SPECIES

OF LAKE MARlUrAND THE lVOZHA HYDRODROME, EGYPT

DURING 1974 MiD 1995

BY
L.M. SHAKWEER*, AND M.M. ABBAS
* Nationallnst. Ocean. and Fisheries, Anfoushy, Alexandria – Egypt.
Key Words: Heavy metals, lake flShes, Egypt.
ABSTRACT
Results ofcomparing the concentration levels of Cu, In, Mn in the
muscle tissues ofthe common fish species inhabiting lake Mariut and
the Nozha Hydrodrome in Alexandria Egypt, during 1974 and 1995
under similar conditions (using the same reagents and apparatus in
the analysis) showed that the levels showed lower values in the
samples collected during 1995 than those collected during 1974from
lake Mariut. Higher concentrations ofthese metals were recorded at
the Nozha Hydrodrome during 1995. The levels ofsuch metals are
less than the international allowable levels. On the other hand Pb
showed increased levels in both sites in 1995 than in 1974 and its
levels are higher than the permissible ones.
The samples of Oreochromis aureus, Sarotherodon galilaeus
and Bagrus bayad collectedfrom the Nozha Hydrodrome during the
years 1974 and 1995 showed that the concentration values ofCu
increased from 3.83 to 13.83, 3.65 to 10.89 and from 3.71 to
5. 52mglKg, the values ojln in the samples showed an increase from
11.93 to 48. 79, 9.83 to 29.48 andfrom 10.74 to 22.72 mglKg and the
values of Mn in the samples increasedfrom 1.40 to 3.34,1.58 to 3.01
and from 1.78 to 3.40 mglKgfor the mentioned species respectively.
For Lake Mariut the percentage increase in the relative
concentrations of Pb during 1974 and 1995 were 80.4%, 66.9%,
293.0% for o. aureus, s. galilaeusand Tilapia zillii respectively.