Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New approach for risk screening of contaminated land

24.06.2013
Following a century of industrialisation, contaminated sites lie abandoned or underutilized all over the world. Now there is a rapid new approach for risk screening of each site, according to studies from the University of Gothenburg, Sweden.

Contaminated land is soil, groundwater or sediment that contains levels of contaminants so high that they exceed natural levels in the environment.

Decisions about remediating contaminated land are often based on risk estimates derived from generic guideline values. Guideline values are used at the screening stage of the risk assessment and have been developed to represent “safe” levels of these contaminants applicable over large geographical areas (usually countries).

These guideline values indicate what may be considered acceptable across the majority of sites. Guideline values more appropriate to specific sites can usually also be calculated. Levels of toxins in the soil exceeding the guideline values may entail risks to humans and the environment.

The simplified system, using general and even site-specific guideline values, may not always capture the true risk of contaminants at the site. Using guideline values can lead to overly conservative remedial decisions, resulting in costly clean-ups that may not be necessary.
The guideline values do not take into account the toxicity of the contaminant mixture or the bioavailability of the toxins, i.e. the extent to which they are taken up by plants or animals at the site. Bioavailability depends on a number of factors such as soil properties.

"One of the most important factors governing the bioavailability of many metals is the soil's pH. In acidic soils, these metals are generally more available to animals and plants. It is estimated that acidic soils cover 30% of the planet's ice-free land area," says Emily Chapman at the Department of Biological and Environmental Sciences.

Emily Chapman's research studies in Gothenburg and Wolfville (Canada) have shown that site-specific risk screening can be improved using a triad approach with tests in undisturbed soil samples from the contaminated site.

"We have developed a simple, rapid triad approach for ecological risk-screening of metal-contaminated acidic soils. It takes into account the contaminants' site-specific chemical properties, mixtures and toxicities. The effects of contaminants can also be distinguished by examining the activity of organisms in soil from the site," says Emily Chapman.

This approach can improve early risk estimates of metal-contaminated acidic soil and tell us more about the contaminants' true site-specific risks. More information also makes it easier to choose the right remediation technology and to determine when it is necessary to excavate the soil.

"The risk-screening approach developed in our research project could also be used for monitoring in-situ (on-site) remediation of acidic metal-contaminated soil" says Emily Chapman.

Thesis title: Ecological risk screening of metal (Pb and Zn) contaminated acidic soil using a triad approach.

Link to thesis: http://hdl.handle.net/22077/32687

Contact:
Emily Chapman, Dept of Biological and Environmental Sciences
Tel: +1 (902) 293 3147, emily.chapman@bioenv.gu.se

Göran Dave, Dept of Biological and Environmental Sciences
Tel: +46 31 786 3776, goran.dave@bioenv.gu.se

Annika Koldenius | idw
Further information:
http://www.gu.se

More articles from Ecology, The Environment and Conservation:

nachricht Safeguarding sustainability through forest certification mapping
27.06.2017 | International Institute for Applied Systems Analysis (IIASA)

nachricht Dune ecosystem modelling
26.06.2017 | Albert-Ludwigs-Universität Freiburg im Breisgau

All articles from Ecology, The Environment and Conservation >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Can we see monkeys from space? Emerging technologies to map biodiversity

An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.

Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...

Im Focus: Climate satellite: Tracking methane with robust laser technology

Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.

Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...

Im Focus: How protons move through a fuel cell

Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.

As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...

Im Focus: A unique data centre for cosmological simulations

Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.

With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...

Im Focus: Scientists develop molecular thermometer for contactless measurement using infrared light

Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine

Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Plants are networkers

19.06.2017 | Event News

Digital Survival Training for Executives

13.06.2017 | Event News

Global Learning Council Summit 2017

13.06.2017 | Event News

 
Latest News

Touch Displays WAY-AX and WAY-DX by WayCon

27.06.2017 | Power and Electrical Engineering

Drones that drive

27.06.2017 | Information Technology

Ultra-compact phase modulators based on graphene plasmons

27.06.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>