Residues of PCDD, PCDF, and PCBs in some marine organisms in Lake Temsah, Ismailia, Egypt

Abstract

Residues of PCDDs/F, non-ortho, mono-ortho PCBs, and other PCBs were monitored in the tissues of mullet fish, bolti fish, bivalves and crab taken from Lake Temsah, at Ismailia, Egypt.

Results showed that 2,3,7,8 Tetra CDD and 1,2,3,7,8 Penta CDD were the most frequently detected PCDD congeners. Similarly, 2,3,7,8 Tetra CDF, 1,2,3,7,8 Penta CDF and 2,3,4,7,8 Penta CDF were the most frequently detected PCDF congeners. No relationship was apparent between the concentrations of detected PCDDs congeners and the degree of chlorination, except with crab samples in which an increase in the chlorination coincided with a decrease in the concentrations of the congeners.

In PCDF congeners, detected residues have had a reversed relationship with chlorination increase. In PCDD congeners, Octa CDD had the highest detected concentrations in the two fish species, while in the bivalves and crab, 2,3,7,8 Tetra CDD had the highest concentrations. The mullet fish had the highest total PCDDs concentration, at 0.398 pg/g fresh weight, followed by crab at 0.395 pg/g fresh weight, then bivalves and bolti fish at 0.187 and 0.062 pg/g fresh weight, respectively. In all the examined organisms, the total concentrations of PCDFs were much higher than the total concentrations of the PCDD congeners. The WHO–TEQ values were 11.92, 39.12, 25, and 3.6 pg/g fresh weight, for mullet fish, bolti fish, bivlaves and crab, respectively. The concentration of the mono-ortho congeners CB 118 was the highest detected of all non-ortho and mono-ortho PCBs congeners, with values of 0.382, 0.022, 0.231 and 0.357 ng/g fresh weight, in mullet fish, bolti fish, bivalves and crab, respectively. The WHO–TEQ concentrations were 0.799, 0.003 pg/g fw, 0.05 pg/g fresh weight, 0.676 pg/g, and 0.799 pg/g fresh weight, for the same species, respectively. The total concentration of PCBs 28, 52, 95, 99, 101, 105, 110, 118, 138, 146, 149, 151, 153, 170, 177, 180, 187 were 6.86 ng/g fresh weight for mullet fish, 0.2 ng/g fresh weight, for bolti fish, 2.72 ng/g fresh weight for bivalves and 2.8 ng/g fresh weight for crab, respectively.

Keywords:

• Residues of PCDDs
• WHO–TEQ concentrations
• non-ortho
• mono-ortho PCBs

Acknowledgement

This study was supported by Interuniversity Consortium of Chemistry for Environment (INCA), Italy, and the Italian Ministry of Foreign Affairs.

Notes

Departmento Scienze Ambientali, Universita Ca’ Foscari di Venezia, Venezia, Italy.

Additional information

Notes on contributors

Mohamed Tawfic Ahmed

Departmento Scienze Ambientali, Universita Ca’ Foscari di Venezia, Venezia, Italy.