Identification of the Contamination Sources by PCBs Using Multivariate Analyses: The Case Study of the Annaba Bay...

Area of Science:

• Environmental Chemistry
• Marine Pollution Studies
• Analytical Chemistry

Background:

• Persistent Organic Pollutants (POPs), including indicator polychlorinated biphenyls (PCBs), pose significant environmental risks.
• Annaba Bay in the Mediterranean Sea receives contaminated discharges from industrial activities and natural watercourses.
• Identifying pollution sources is crucial for effective environmental management and remediation.

Purpose of the Study:

• To quantify Persistent Organic Pollutants (POPs), specifically seven indicator PCB congeners, in the water and sediment of Boujemaâ and Seybouse wadis and Fertial industrial plant effluents.
• To identify the primary sources of PCB contamination in Annaba Bay using multivariate statistical analysis.
• To establish a methodological framework for source identification applicable to other global case studies.

Main Methods:

• Sample collection from two wadis (Boujemaâ, Seybouse) and industrial effluents (Fertial).
• Quantification of seven PCB congeners using liquid-liquid extraction and gas chromatography/mass spectrometry (GC-MS).
• Multivariate analysis, including Principal Component Analysis (PCA) and Hierarchical Cluster Analysis (HCA), for source apportionment.

Main Results:

• PCB concentrations in sediments ranged from 1 to 6.4 μg/kg dry weight, and up to 0.027 μg/L in waters.
• Multivariate analysis indicated that urban/domestic and agricultural/industrial activities are the main sources of PCB emissions.
• Boujemaâ wadi was identified as the primary contributor to PCB pollution, followed by Seybouse wadi and the Fertial industrial plant.

Conclusions:

• The study successfully identified and apportioned sources of PCB pollution in Annaba Bay.
• The methodology presented offers a robust approach for assessing and managing POPs contamination in similar coastal environments.
• Findings highlight the need for targeted interventions to mitigate pollution from identified sources and protect marine ecosystems.