PCDD/Fs accumulation in pine needles: variation with species and pine needle age

Area of Science:

• Environmental Science
• Analytical Chemistry
• Botany

Background:

• Pine needles are established biosamplers for atmospheric polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs).
• Variations in PCDD/F accumulation based on pine species and needle age are not well understood, limiting precise biosampling applications.

Purpose of the Study:

• To investigate how pine tree species and needle age affect the accumulation of PCDD/Fs.
• To provide data for optimizing the selection of pine needles for effective atmospheric monitoring.

Main Methods:

• Quantitative analysis of PCDD/Fs in pine needles using gas chromatography high-resolution mass spectrometry.
• Scanning electron microscopy (SEM) to examine needle surface morphology and cuticular wax.
• Collection of needles from four pine species across three sites in Hangzhou, China.

Main Results:

• Pinus massoniana and Cedrus deodara showed higher PCDD/F absorption compared to Pinus thunbergii and Pinus parviflora.
• Increased cuticular wax and secretions in P. massoniana and C. deodara needles correlate with higher PCDD/F levels.
• PCDD/F concentrations increased with needle age (0.3 to 2.3 years), linked to enhanced lipid and wax content.

Conclusions:

• Pine species and needle age significantly influence PCDD/F bioaccumulation.
• Cuticular characteristics and age-related changes in pine needles are key factors in PCDD/F uptake.
• Results guide the selection of optimal pine species and needle age for accurate atmospheric PCDD/F monitoring.