GC-MS/MS analysis for source identification of emerging POPs in PM_2.5

Area of Science:

• Environmental Chemistry
• Atmospheric Science
• Toxicology

Background:

• Emerging persistent organic pollutants (POPs) pose risks due to persistence and toxicity.
• Limited data exists on the occurrence and distribution of these emerging POPs in PM2.5.
• Particulate matter (PM2.5) is a significant atmospheric pollutant with implications for human health and the environment.

Purpose of the Study:

• To develop a sensitive analytical method for trace POPs in PM2.5.
• To investigate the occurrence and distribution of hexachlorobutadiene (HCBD), pentachloroanisole (PCA), and chlorobenzenes (CBs) in Taiyuan's PM2.5 over a year.
• To identify potential sources and formation pathways of these emerging POPs.

Main Methods:

• Ultrasonic solvent extraction and silica gel purification.
• Gas chromatography coupled with electron ionization triple quadrupole mass spectrometry (GC-EI-MS/MS).
• Trace analysis of HCBD, PCA, and CBs in PM2.5 samples collected throughout the year.

Main Results:

• A highly sensitive method with low limits of detection (1.14 × 10⁻⁴–2.74 × 10⁻⁴ pg m⁻³) and quantitation (3.80 × 10⁻⁴–9.14 × 10⁻⁴ pg m⁻³).
• First-time detection of HCBD (mean 3.69 pg m⁻³) and PCA (mean 1.84 pg m⁻³) in Taiyuan's PM2.5.
• HCBD linked to unintentional industrial emissions or incineration; PCA potentially formed via O₃-induced photoreaction; CBs correlated with coal combustion or agricultural activities.

Conclusions:

• The study established a reliable method for emerging POPs analysis in PM2.5.
• It provided crucial data on the contamination profiles of HCBD, PCA, and CBs in Taiyuan.
• Understanding POPs sources is vital for targeted pollution control strategies.