Photochemical sample treatment for extracts clean up in PCB analysis from sediments

Area of Science:

• Environmental Chemistry
• Analytical Chemistry
• Green Chemistry

Background:

• Sample purification for polychlorinated biphenyls (PCBs) determination in sediments is a significant source of pollution due to extensive organic solvent use.
• Existing chromatographic purification methods are effective but contribute to environmental burden and operational costs.

Purpose of the Study:

• To introduce and evaluate photochemical sample treatment as a novel, environmentally friendly alternative for cleaning sediment extracts in PCBs analysis.
• To compare the efficiency, robustness, and quality parameters of photochemical treatment against conventional chromatographic purification techniques.
• To validate the photochemical method using certified reference sediment for reliable PCBs determination.

Main Methods:

• Application of photochemical sample treatment for the selective removal of interfering organic substances in sediment extracts.
• Comparative analysis of photochemical treatment versus established chromatographic purification methods.
• Validation of the entire procedure through replicate analysis of certified reference sediment, assessing recovery, linearity, and reproducibility.

Main Results:

• Quantification limits (LOQ) for PCBs ranged from 1 to 3.1 ng g⁻¹.
• Relative standard deviation (RSD) for each congener was below 15%, with recoveries between 40-130%.
• Analysis of real and certified samples demonstrated comparable or superior detection thresholds with the photochemical method.

Conclusions:

• Photochemical sample treatment is an effective and robust methodology for the clean-up of sediment extracts in PCBs analysis.
• This green chemistry approach significantly reduces organic solvent consumption, offering cost and environmental advantages over chromatographic methods.
• The validated photochemical method provides reliable and sensitive PCBs determination in environmental samples.