Method development for simultaneous analyses of polycyclic aromatic hydrocarbons and their nitro-, oxy-, hydroxy-...

Area of Science:

• Environmental Chemistry
• Analytical Chemistry
• Mass Spectrometry

Background:

• Polycyclic aromatic hydrocarbons (PAHs) and their derivatives (nitro-PAHs, oxy-PAHs, OH-PAHs) are common environmental contaminants found in sediments.
• Accurate quantification methods are crucial for assessing the environmental impact of these co-existing compounds.

Purpose of the Study:

• To develop and validate a comprehensive analytical method for quantifying PAHs, nitro-PAHs, oxy-PAHs, and OH-PAHs in sediment samples.
• To establish a reliable technique for environmental monitoring and risk assessment.

Main Methods:

• Sediment samples were extracted using accelerated solvent extraction and purified via solid-phase extraction (SPE) with alumina-n and aminopropyl cartridges.
• Extracts were fractionated and analyzed using gas chromatography-mass spectrometry (GC-MS) with electron ionization (EI) and negative ion chemical ionization (NICI), and liquid chromatography-tandem mass spectrometry (LC-MS/MS).
• Specific detection modes were employed: GC-EI-SIM for PAHs, GC-NICI-SRM for nitro-PAHs, GC-EI-SRM for oxy-PAHs, and LC-ESI-MS/MS for OH-PAHs.

Main Results:

• The method successfully quantified 44 analytes, including 16 PAHs, 14 nitro-PAHs, 9 oxy-PAHs, and 5 OH-PAHs, along with 6 deuterated surrogates.
• Recovery percentages ranged from 52.8% to 114.1%, with repeatability (RSD%) below 10% for most analytes.
• Limits of detection were low, ranging from 0.002 to 0.1 ng/g across the different analyte groups.

Conclusions:

• The developed analytical method is validated and demonstrates high efficiency, accuracy, and sensitivity for determining PAHs and their derivatives in sediment.
• The method's applicability was confirmed by detecting target compounds in real river sediment samples, highlighting its practical utility for environmental analysis.