SEGH Articles

Urban soil of Athens, Greece: Local geology beats human pollution on trace elements

04 June 2014
Bearing in mind the historical absence of heavy industry within the Greater Athens and Piraeus area, the tested hypotheses was that local geology is important in controlling the distribution of potentially harmful trace elements in urban soil.


Bearing in mind the historical absence of heavy industry within the Greater Athens and Piraeus area, the tested hypotheses was that local geology is important in controlling the distribution of potentially harmful trace elements in urban soil.

 

The first geochemical baseline study of surface soil in Athens, based on a systematic sampling survey covering the Greater Athens and Piraeus area, was recently performed by the Laboratory of Economic Geology and Geochemistry, University of Athens. In the study, the contents of the major elements Fe, Al, K and Ca, and potentially harmful elements Ni, Cr, Co, Mn, As, Pb, Zn, Cu, Cd, Sb and Sn were determined.

Athens, Greece is a European city with a very long history. The area has been continuously inhabited for more than 7,000 years and provides an example of early urbanization in the ancient world. However, unlike most European capitals, the urbanization of modern Athens was not related to the Industrial Revolution. The city experienced rapid population growth from ~400,000 people in 1925 to > 1,000,000 by 1950.  The population increase of modern Athens is marked by the return of Greek refugees from Asia Minor in the 1920s after World War I, and extensive internal migration after World War II. Today, the urban area of Greater Athens and Piraeus has a population of ~ 3.2 million over an area of 412 km2. This constitutes ~ 1/3rd of the Greek population. In addition, this area is the center of economic and commercial activities for the country.

Principle Component Analysis and Cluster Analysis, combined with analysis of soil heterogeneity and spatial variability, were implemented in order to distinguish the sources of elements and their classification as geogenic or anthropogenic. It was found that the major factor controlling variability of the chemical composition of surface soil was the bedrock chemistry, resulting in a significant enrichment in concentrations of Ni, Cr, Co and possibly As. Greek soil is naturally enriched in Cr, Ni, Co and Mn as a result of the widespread occurrence of basic and ultrabasic rocks. Furthermore, elevated As concentrations in soil and natural waters have been linked to metamorphic rocks in Greece.

Anthropogenic influences were also significant, controlling a spectrum of elements that are typical of human activities, i.e. Pb, Zn, Cu, Cd, Sb, and Sn. The highest concentrations of the classical urban contaminants were observed in the surface soil from roadside verges and in the older parts of the city, as well as the densely populated areas. Spatial distribution patterns of PHEs demonstrated an increase in concentrations of the anthropogenically induced metals towards the city core and the port of Piraeus. On the contrary, the naturally derived Ni, Cr and Co are mainly enriched in the periphery of Athens Basin.

 

Taking into account the salient enrichment of geogenic PHEs in Athens soil, comparing with concentrations measured in other cities around the world, this study provides base for further research into PHE mobility and bioaccessibility. This work is also important for under the current economic conditions the development of urban agriculture is an emerging initiative of several municipalities. The results of the study are presented in a publication in the Science of the Total Environment: http://dx.doi.org/10.1016/j.scitotenv.2014.02.133

 

Dr. Ariadne Argyraki, Assistant Professor in Geochemistry, University of Athens (argyraki@geol.uoa.gr)

Keep up to date

SEGH Events

Submit Content

Members can keep in touch with their colleagues through short news and events articles of interest to the SEGH community.

Science in the News

Latest on-line papers from the SEGH journal: Environmental Geochemistry and Health

  • Status, source identification, and health risks of potentially toxic element concentrations in road dust in a medium-sized city in a developing country 2017-09-19

    Abstract

    This study aims to determine the status of potentially toxic element concentrations of road dust in a medium-sized city (Rawang, Malaysia). This study adopts source identification via enrichment factor, Pearson correlation analysis, and Fourier spectral analysis to identify sources of potentially toxic element concentrations in road dust in Rawang City, Malaysia. Health risk assessment was conducted to determine potential health risks (carcinogenic and non-carcinogenic risks) among adults and children via multiple pathways (i.e., ingestion, dermal contact, and inhalation). Mean of potentially toxic element concentrations were found in the order of Pb > Zn > Cr(IV) > Cu > Ni > Cd > As > Co. Source identification revealed that Cu, Cd, Pb, Zn, Ni, and Cr(IV) are associated with anthropogenic sources in industrial and highly populated areas in northern and southern Rawang, cement factories in southern Rawang, as well as the rapid development and population growth in northwestern Rawang, which have resulted in high traffic congestion. Cobalt, Fe, and As are related to geological background and lithologies in Rawang. Pathway orders for both carcinogenic and non-carcinogenic risks are ingestion, dermal contact, and inhalation, involving adults and children. Non-carcinogenic health risks in adults were attributed to Cr(IV), Pb, and Cd, whereas Cu, Cd, Cr(IV), Pb, and Zn were found to have non-carcinogenic health risks for children. Cd, Cr(IV), Pb, and As may induce carcinogenic risks in adults and children, and the total lifetime cancer risk values exceeded incremental lifetime.

  • Erratum to: Preliminary assessment of surface soil lead concentrations in Melbourne, Australia 2017-09-11
  • In vivo uptake of iodine from a Fucus serratus Linnaeus seaweed bath: does volatile iodine contribute? 2017-09-02

    Abstract

    Seaweed baths containing Fucus serratus Linnaeus are a rich source of iodine which has the potential to increase the urinary iodide concentration (UIC) of the bather. In this study, the range of total iodine concentration in seawater (22–105 µg L−1) and seaweed baths (808–13,734 µg L−1) was measured over 1 year. The seasonal trend shows minimum levels in summer (May–July) and maximum in winter (November–January). The bathwater pH was found to be acidic, average pH 5.9 ± 0.3. An in vivo study with 30 volunteers was undertaken to measure the UIC of 15 bathers immersed in the bath and 15 non-bathers sitting adjacent to the bath. Their UIC was analysed pre- and post-seaweed bath and corrected for creatinine concentration. The corrected UIC of the population shows an increase following the seaweed bath from a pre-treatment median of 76 µg L−1 to a post-treatment median of 95 µg L−1. The pre-treatment UIC for both groups did not indicate significant difference (p = 0.479); however, the post-treatment UIC for both did (p = 0.015) where the median bather test UIC was 86 µg L−1 and the non-bather UIC test was 105 µg L−1. Results indicate the bath has the potential to increase the UIC by a significant amount and that inhalation of volatile iodine is a more significant contributor to UIC than previously documented.