– The risks that arsenic-contaminated materials can cause to the environment can be reduced by for example chemical stabilisation, leading to the reduced arsenic solubility, mobility and uptake by living organisms, says Jurate Kumpiene, professor in Waste Science and Technology at Luleå University of Technology.
Arsenic in the environment is a significant health risk affecting over 20 million people worldwide. In Sweden due to the industrial activities, such as glass works and wood impregnation, multiple point sources of As contamination are scattered over the country with soil As reaching alarming. In addition, naturally elevated As levels in the bedrock is a reason that ca 5% of individual groundwater wells used for drinking water in Northern and Central Sweden contain As levels above the WHO limit of 10 µg/l.
Extensive research efforts have been put into supplying safe water and developing techniques for arsenic removal from groundwater, but much less is known about how to safely managed solid materials, including contaminated masses and used arsenic-rich water treatment filters that can no longer be regenerated.
A landfill usually serves as a final sink of such materials. But the risks for arsenic release to leachate and, if a landfill is not properly constructed, back to groundwateris high. This in turn would require leachate and groundwater treatment using sorbents and coagulants, which will end up in a landfill, leading to a perpetual treatment cycle. To brake this cycle, arsenic-rich residues should be stabilized prior to disposal. Research on this subject is still limited, while the extent of the problem increases due to the intensive remediation actions of arsenic in the environment. Safe and long-lasting disposal of arsenic-rich residues is an important research challenge that has to be addressed in order to reduce the release and circulation of this toxic element in the environment.
– Arsenic in the environment is a significant health risk. Because of the high human toxicity and carcinogenicity, arsenic is among the priority contaminants worldwide, says Jurate Kumpiene.
The project is implemented in cooperation with researchers in Energy Engineering at LTU and KTH-International Groundwater Arsenic Research Group, as well as companies: Piteå Såg & Hyvleri, and Geogen Produktion AB.