Metal levels in muscle tissues of Two fish species from Libyan coast

Abstract EN

Two Mediterranean demersal fish species Scorpaena porcus and Pagellus erythrinus were used as biomonitoring species for heavy metals concentrations.

Thirty-six Scorpaena porcus fish specimens and thirty four fish specimens of Pagellus erythrinus species caught during August 2005، from two Libyan coastal sites namely Tajura and Alkhomus situated at southern- middle part of the Mediterranean at the Libyan coast 18 km and 100 km east of Tripoli، respectively.

Very close total lengths with very reasonable coefficient of length variance (around 5%) for each fish species were considered.

Wet reflux digestion technique using Nitric acid and hydrogen peroxide was applied for fish muscle tissues digestion، metals concentrations were then measured by flame Atomic Absorption.

The average metal concentrations (mg/kg wet wt.) in the muscle tissues of S.

porcus were (15.2949 ±4.3756)، (7.7180±3.5440)، (0.9376 ±0.2164) and، (0.3777±0 .1875) for Iron، Zinc، Copper and Manganese، respectively.

The average metals concentrations (mg/kg dry wt.) in muscle tissues P.

erythrinus were (27.5023±4.8974)، (26.6227±9.1646)، (3.2398±0.7702) and (0.8104±0.2733)، for Iron، Zinc Copper and Manganese، respectively.

As consequence of the wet –dry flesh weight ratio(metal concentration expressed per dry weight is actually 4-5 times magnitude the concentration expressed per wet weight)، as such the interspecies metal concentration comparison of both species based either on dry weight or wet weight for both species revealed that metal concentrations in S.

porcus were higher than P.

erythrinus.

Metals concentrations expressed similar rankings in both studied fish species were Fe>Zn >Cu>Mn.