Heavy metals in atmospheric surrogate dry deposition
1Universita degli Studi di Bologna, Dipartimento di Chimica Industriale e dei Materiali, Italy.
Chemosphere
|July 21, 2000
Summary
This study assessed toxic heavy metal dry deposition using two samplers and evaluated digestion techniques. The Teflon bomb method offered the highest recovery, and the DAS sampler collected 2-3 times more metals than the DRY sampler.
Area of Science:
- Environmental Science
- Analytical Chemistry
- Atmospheric Science
Background:
- Assessing heavy metal deposition is crucial for environmental monitoring.
- Standardized methods for dry deposition analysis are needed.
- Toxic heavy metals (Cd, Cr, Cu, Ni, Pb, V, Zn) pose environmental risks.
Purpose of the Study:
- To develop and validate a method for assessing heavy metal dry deposition.
- To compare the efficiency of different sample digestion techniques.
- To evaluate the performance of two distinct dry deposition samplers.
Main Methods:
- Dry deposition samples were collected over one year in Bologna, Italy.
- Two samplers were used: a dry solid surface sampler (DRY) and a water layer surface sampler (DAS).
- Three digestion techniques (Teflon bomb, microwave, Teflon flask) were evaluated for trace metal analysis.
Main Results:
- The Teflon bomb digestion method yielded the highest recovery rates (90-95%) for heavy metals.
- The DAS sampler demonstrated 2-3 times greater collecting efficiency for several elements compared to the DRY sampler.
- Monthly deposition fluxes of heavy metals were quantified.
Conclusions:
- The Teflon bomb method is recommended for digesting dry deposition samples for trace metal analysis.
- The DAS sampler is more efficient for collecting heavy metals via dry deposition than the DRY sampler.
- This methodological approach enhances the accuracy of atmospheric heavy metal deposition assessments.
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