SEGH Articles

Urban Geochemical Mapping by the Geochemistry Expert Group of EuroGeoSurveys

25 March 2016
Given the fact that by 2050 more than 80% of the European population will be living in cities (United Nations, 2014), the quality of the urban environment is becoming an important issue in the 21st century.

Given the fact that by 2050 more than 80% of the European population will be living in cities (United Nations, 2014), the quality of the urban environment is becoming an important issue in the 21st century. Ever since the industrial revolution, with a peak after the Second World War, the urban environment has been contaminated with many toxic elements and compounds, which are being emitted by a wide variety of human activities (industry, traffic, domestic heating, coal and oil combustion, incineration, construction activities, etc.),  and often accumulate in urban soil.

Since, the 1970s a conscious attempt is being made in many countries to develop industrial estates outside the residential, commercial, and recreational parts of cities. Within the urban structure remain, however, the brownfield sites, and the enormous problem of their redevelopment in order to reduce the pressure on greenfield sites.  As many health-related problems are linked to the state of the urban environment, the European citizens want to know the geochemistry of the land their houses are built on. Moreover, it is very important that the chemical quality of soil in public places, such as schoolyards, parks, playgrounds, kindergartens, recreation areas, and workplaces is known. Estate agents need to know the quality of the land they are marketing, and insurance brokers the potential risks to their customers.

The Geochemistry Expert Group of EuroGeoSurveys realising that knowledge about soil contamination, geochemical background concentrations, and detailed spatial element distribution is becoming a key issue in urban planning initiated in 2008 an Urban Geochemistry project with the acronym URGE.  The first part was the compilation of all hitherto knowledge and its publication in a full-colour textbook “Mapping the Chemical Environment of Urban Areas” (Johnson et al., 2011):

The first part of the textbook covers more general aspects of urban chemical mapping, with an overview of current practice, and reviews of different features of the component methodologies (chemical analysis, quality control, data interpretation and presentation, risk assessment, etc.). The second part includes a number of case studies from different urban areas, principally from Europe, but with some contributions from North America, Africa and Asia.  Many of the chapters discuss the potential impact on human health and describe the multi-disciplinary effort, usually supported by legislation, required to deal with the legacy of contamination found in many urban areas.

Apart from the publication of the textbook, different urban geochemical projects were carried out in different European cities, and the results are in the process of being published in a Special Issue of the Journal of Geochemical Exploration on Urban Geochemical Mapping, thus ending the first phase of the URGE project.

One of the results of the textbook and the urban geochemical surveys that were carried out in Europe is that the comparability between investigations and results from different European cities, the European overview, is missing. Thus, a second phase of the URGE project is in the process of being initiated. The suggested project aims at advising the city administration how such studies should be carried out, and how the data are best stored, evaluated and presented.  Furthermore, a directly comparable database shall be built for a number of European reference cities (N=15-25), participating in the proposed project.  For this purpose, a detailed manual for sampling topsoil in urban areas has been written (Demetriades and Birke, 2015a):

 

As there was a demand for a comprehensive Urban Geochemical Mapping Manual by the EU COST  Sub-Urban project (http://www.sub-urban.eu/), the EuroGeoSurveys’ Geochemistry Expert Group was commissioned to write it (Demetriades and Birke, 2015b) as part of WG 2.6 “Geochemistry” (http://sub-urban.squarespace.com/new-index-1/#geotechnical-modelling-hazards-wg-25):

 

 

by EurGeol Alecos Demetriades

former Director of the Division of Geochemistry and Environment,

Hellenic Institute of Geology and Mineral Exploration, Athens


References

Demetriades, A., Birke, M., 2015a.  Urban Topsoil Geochemical Mapping Manual (URGE II).  EuroGeoSurveys, Brussels, 52 pp., http://www.eurogeosurveys.org/wp-content/uploads/2015/06/EGS_Urban_Topsoil_Geochemical_Mapping_Manual_URGE_II_HR_version.pdf.

Demetriades, A., Birke, M., 2015b.  Urban Geochemical Mapping Manual:  Sampling, Sample preparation, Laboratory analysis, Quality control check, Statistical processing and Map plotting.  EuroGeoSurveys, Brussels, 162 pp., http://www.eurogeosurveys.org/wp-content/uploads/2015/10/Urban_Geochemical_Mapping_Manual.pdf.

Johnson, C.C., Demetriades, A., Locutura, J., Ottesen, R.T. (Editors), 2011.  Mapping the chemical environment of urban areas.  Wiley-Blackwell, John Wiley & Sons Ltd., Chichester, U.K., 616 pp., http://eu.wiley.com/WileyCDA/WileyTitle/productCd-0470747242.html.

 

United Nations, 2014.  World Urbanization Prospects:  The 2014 Revision, Highlights (ST/ESA/SER.A/352). United Nations, Department of Economic and Social Affairs, Population Division, New York, 32 pp., http://esa.un.org/unpd/wup/Highlights/WUP2014-Highlights.pdf

As there was a demand for a comprehensive Urban Geochemical Mapping Manual by the EU COST  Sub-Urban project (http://www.sub-urban.eu/), the EuroGeoSurveys’ Geochemistry Expert Group was commissioned to write it (Demetriades and Birke, 2015b) as part of WG 2.6 “Geochemistry” (http://sub-urban.squarespace.com/new-index-1/#geotechnical-modelling-hazards-wg-25):

Keep up to date

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

  • Membrane fouling control by Ca 2+ during coagulation–ultrafiltration process for algal-rich water treatment 2019-04-16

    Abstract

    Seasonal algal bloom, a water supply issue worldwide, can be efficiently solved by membrane technology. However, membranes typically suffer from serious fouling, which hinders the wide application of this technology. In this study, the feasibility of adding Ca2+ to control membrane fouling in coagulation–membrane treatment of algal-rich water was investigated. According to the results obtained, the normalized membrane flux decreased by a lower extent upon increasing the concentration of Ca2+ from 0 to 10 mmol/L. Simultaneously, the floc particle size increased significantly with the concentration of Ca2+, which leads to a lower hydraulic resistance. The coagulation performance is also enhanced with the concentration of Ca2+, inducing a slight osmotic pressure-induced resistance. The formation of Ca2+ coagulation flocs resulted in a looser, thin, and permeable cake layer on the membrane surface. This cake layer rejected organic pollutants and could be easily removed by physical and chemical cleaning treatments, as revealed by scanning electron microscopy images. The hydraulic irreversible membrane resistance was significantly reduced upon addition of Ca2+. All these findings suggest that the addition of Ca2+ may provide a simple-operation, cost-effective, and environmentally friendly technology for controlling membrane fouling during coagulation–membrane process for algal-rich water treatment.

  • Evaluation of the raw water quality: physicochemical and toxicological approaches 2019-04-13

    Abstract

    Environmental degradation has increased, mainly as a result of anthropogenic effects arising from population, industrial and agricultural growth. Water pollution is a problem that affects health, safety and welfare of the whole biota which shares the same environment. In Goiânia and metropolitan region, the main water body is the Meia Ponte River that is used for the abstraction of water, disposal of treated wastewater and effluents. In addition, this river receives wastewater from urban and rural areas. The aim in this present study was to evaluate the quality of raw water by some physical, chemical and toxicological tests. The physicochemical results found high levels of turbidity, conductivity, aluminum, phosphorus and metal iron, manganese, copper and lithium when compared to the standards of the Brazilian legislation. The values found of toxicity demonstrated a high degree of cytotoxicity and genotoxicity. Therefore, it was concluded that the Meia Ponte River has been undergoing constant environmental degradation, causing the poor quality of its waters. Thus, measures for the prevention and recovery should be adopted for the maintenance of the Meia Ponte River.

  • Review of the nature of some geophagic materials and their potential health effects on pregnant women: some examples from Africa 2019-04-11

    Abstract

    The voluntary human consumption of soil known as geophagy is a global practice and deep-rooted in many African cultures. The nature of geophagic material varies widely from the types to the composition. Generally, clay and termite mound soils are the main materials consumed by geophagists. Several studies revealed that gestating women across the world consume more soil than other groups for numerous motives. These motivations are related to medicinal, cultural and nutrients supplementation. Although geophagy in pregnancy (GiP) is a universal dynamic habit, the highest prevalence has been reported in African countries such as Kenya, Ghana, Rwanda, Nigeria, Tanzania, and South Africa. Geophagy can be both beneficial and detrimental. Its health effects depend on the amount and composition of the ingested soils, which is subjective to the geology and soil formation processes. In most cases, the negative health effects concomitant with the practice of geophagy eclipse the positive effects. Therefore, knowledge about the nature of geophagic material and the health effects that might arise from their consumption is important.