Projects / Programmes
Assessment of the risk from metal contaminated soils and aerosols to human health through advanced in vitro gastrointestinal and respiratory bioaccessibility tests
| Code |
Science |
Field |
Subfield |
| 1.08.00 |
Natural sciences and mathematics |
Control and care of the environment |
|
| Code |
Science |
Field |
| P300 |
Natural sciences and mathematics |
Analytical chemistry |
Risk assessment, human health, soil, aerosols, mining, lead, pollution, ingestion, inhalation, in vitro bioaccessibility tests, mineralogical composition, instrumental methodologies
Researchers (6)
Organisations (3)
Abstract
This project deals with the development of in vitro extraction methods to access the human bioaccessibility of metals after ingestion of soils or inhalation of aerosols using physiological solutions that mimic the composition of the gastrointestinal and respiratory tract solutions. To account for all kind of eventualities (worst case scenario) an exhaustive extraction of metals with the respective solutions in on-line setups is planned.
The in vitro extraction methods developed will be applied to lead-contaminated soil and aerosols collected in the Meža valley (N. Slovenia) as in this (former) lead mining/smelting area serious lead-related health problems are present, especially related to pre-school children as a result of hand-to-mouth behaviour. The lead-contaminated soils and aerosols will additionally undergo physico-chemical characterization with state-of-the-art instrumental techniques providing more insight into the mineralogical composition. The individual minerals identified will also be subjected to in vitro extraction to be able to quantify their individual contribution to human bioaccessibility.
Correlating the in vitro extraction data with mineralogical lead data will enhance the understanding of lead bioaccessibility and may ultimately lead to a predictive tool for estimating the bioaccessibility based exclusively on the mineralogical composition of soil and aerosols.
Significance for science
Risk assessment related to inhalation of aerosols or ingestion of soil is traditionally performed via batch extraction procedures by simulation of the gastrointestinal or respiratory tract conditions. We developed novel techniques yielding i) a continuous data stream (kinetics) for retrieval of metal-related soil leaching mechanisms to quantify the liability and ii) leaching data for PbS nanoparticles to assess the potential danger of aerosols containing PbS. Especially the use of a laser ablation device to generate nanoparticles and impinge them in an appropriate solution mimicking a certain body intake route must be seen as an absolute novelty with many potential applications. The ever increasing development and use of nanoparticles means that their evaluation within legislation is of utmost importance as expressed by REACH (Registration, Evaluation, Authorization, and Restriction of Chemical Substances (EC No. 1907-2006). This project has developed some tools to aid in the evaluation of such materials to assess health risks.
Further development of physico-chemical characterization methods for nano-, micro- and macroparticles, and in particular the modeling of experimental results, has offered new insights in leaching mechanisms of metals from soil and aerosols in the gastrointestinal and respiratory tracts. It was e.g. found that via particle diffusion more than 50% of Pb in extremely insoluble PbS nanoparticles can potentially be leached in the human lungs. Overall the findings seem to indicate that nanoparticles are potentially very dangerous from a leaching-point-of-view. Other modeling achievements have opened up possibilities to predict environmental metal leachability from soils based on a sophisticated multiple kinetic Langmuir model taking into account the binding to the respective mineralogical phases of the soil. We stirred up a lot of interest with this fundamental work during presentations at conferences.
So far the project has yielded 4 papers (3 published, 1 in press) in international journals with a high impact factor (3 of them in the first quartile and 1 in the second quartile). Additionally, 1 more paper has been submitted to an international journal whereas 2 other ones are in the stage of final preparation before submission. Also a more popular paper has been published in the national newspaper Delo related to the Icelandic volcanic eruption.
Significance for the country
The results of the project provide methodologies that provide a greater understanding of the risks that the contaminated soils and aerosols present when analyzed on a site-specific basis. Therefore, the methodologies allow greater insight into the necessary measures that need to be taken in order to ensure a low risk environment.
Indoor industrial pollution is a very important area of study and represents a significant area with which the methodologies and understanding gained from this project has a clear application. For example, the cutting and grinding processes used in the manufacture of crystal glass, known for its high Pb content, results in a large amount of ultrafine particles. Therefore, knowledge of the potential risk that these fine particles represent when inhaled is crucial.
The use of forensic geochemistry for the characterization of the Pb pollution present in the Mežica valley, Slovenia with regards to Pb isotope ratios, will provide a methodology to allow a better understanding as to the scale and influence the current activities of the Pb smelter present in the area, concerning Pb pollution.
Additionally the project has served as springboard for several scientists at the beginning of their career to gain experience in the development of analytical tools for risk assessment and all their implications; as a matter of fact one of them gained expert knowledge in the field of nanoparticles generation by laser ablation that landed him a job in Germany.
Most important scientific results
Annual report
2008,
2009,
final report,
complete report on dLib.si
Most important socioeconomically and culturally relevant results
Annual report
2008,
2009,
final report,
complete report on dLib.si
