Metal particle seeding on urban surface samples

Area of Science:

• Environmental Science
• Materials Science
• Analytical Chemistry

Background:

• Accurate estimation of particle resuspension requires homogeneous particle distribution on surfaces.
• Seeding or deposition in experimental chambers is vital for quantifying initial concentrations in resuspension studies.

Purpose of the Study:

• To evaluate the seeding efficiency of metal particles on various urban surfaces.
• To compare solubilization techniques for quantifying silver and gold particles.
• To determine the homogeneity of particle distribution for resuspension experiments.

Main Methods:

• Comparison of solubilization techniques for silver (1.3-3.2 μm, 0.5-1.0 μm) and gold (Ø˂5 μm) particles.
• Chemical quantification using Inductively Coupled Plasma Mass Spectrometry (ICP-MS).
• Seeding tests on slate, facade coating, tile, and glass surfaces using gold particles.
• Analysis of particle distribution homogeneity using Scanning Electron Microscopy with Energy Dispersive X-ray spectroscopy (SEM-EDX).

Main Results:

• Gold particles demonstrated significantly higher solubilization yields (82%-98%) compared to silver particles (23%-84%).
• Seeded concentrations on urban surfaces ranged from 1900 ± 390 μg.m⁻² (glass) to 10,900 ± 1,900 μg.m⁻² (facade coating).
• A relative standard deviation of 9.5% for measured concentrations indicated good seeding homogeneity, below equipment measurement uncertainty (≈14%).

Conclusions:

• Gold particles are more suitable for seeding due to superior recovery rates in quantification.
• The developed seeding method ensures homogeneous particle distribution on diverse urban surfaces.
• This methodology provides a reliable foundation for future particle resuspension studies.