WP3: Heavy metals

CONffIDENCE WP3: Heavy metals



  • Development of two validated detection methodologies for determination of inorganic arsenic in food based on (i) a novel cytosensor approach using luminescent recombinant bacterial cell biosensors (cytosensor) and (ii) solid phase extraction/atomic absorption spectrometry (SPE-AAS).
  • Development of two validated detection methodologies for the determination of methylmercury in marine based food and feed based on (i) the cytosensor approach and (ii) the SPE-AAS approach.
  • Impact demonstration: (i) exposure assessment via regional survey in fish and fish feed, and (ii) methylmercury versus PUFA risk-benefit analysis in fish.


The total contents of the heavy metals lead, cadmium and mercury in food and feed are regulated by (EC) Nos 466/2001/EC, 78/2005/EC, 2002/32/EC and 2003/100/EC. However, for some heavy metals the chemical form (i.e. their speciation) is important in terms of food and feed safety. While for arsenic the inorganic forms are the most toxic and for mercury, methylmercury is the most toxic form, WP3 will focus on the development of simplified and inexpensive methods for these analytes. Since seafood is the major dietary source for arsenic and mercury in the European population, CONffIDENCE will focus on marine feed and seafood as sample matrices of interest. Two parallel approaches will be followed:

  1. a cytosensor approach using luminescent recombinant bacterial cell biosensors (CYT) and
  2. a solid phase extraction approach followed by atomic absorption spectrometry (SPE-AAS).

1. CYT. Two highly innovative and specific cytosensors, for inorganic arsenic and for methylmercury will be developed. To this end CONffIDENCE will adopt a luminescent recombinant bacterial cell concept, which feasibility and selectivity has been preliminary shown in water analysis, and turn it into a robust and simple test format for marine based food and feed. The cytosensor contains a reporter gene under a highly specific inorganic or organic metal species responsive element of interest. Such a novel assay will measure only the bioactive fraction available to the living cells and set a new standard for metal speciation analysis in food and feed.

2. SPE-AAS. A simplified approach is urgently needed in order to allow the monitoring of larger numbers of samples for priority metal species in the food chain. CONffIDENCE will boost this issue in WP3 by the development of a validated solid phase extraction (SPE)/AAS approach in which inorganic arsenic and methylmercury are pre-separated followed by conventional AAS analysis.

The methods will be in-house validated following international guidelines, including a critical comparison with reference methods based on HPLC-ICPMS (inorganic arsenic) and GC-ICPMS (methylmercury). Small-scale interlab studies will be conducted. The impact of the new assays will be demonstrated via surveys on the inorganic arsenic and methylmercury content in samples of seafood and fish feed. Additionally the obtained data will together with data on the content of polyunsaturated fatty acids (PUFA) in the same samples be used as a risk-benefit impact demonstrator for the assessment of seafood consumption (in collaboration with WP1a).

Work Package leader

Dr Jens J. Sloth (Technical University of Denmark, DTU Food, DK)

Jens J. Sloth is a senior scientist in analytical chemistry at the Department of Food Chemistry at DTU Food. He has more than 10 years experience in analytical chemistry with emphasis on trace element analysis and speciation analysis using coupled techniques like HPLC/GC-ICPMS. He has extensive experience with trace element speciation analysis of marine samples

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Work Package deputy leader

Prof. Matti Karp (Tampere University of Technology, TUT, FIN)

 Matti T. Karp is a professor in biotechnology at the Department of of Chemistry and Bioengineering, Tampere University of Technology (TUT). He is the head of Master’s degree programme in biotechnology and of International master’s degree programme in Science and Bioengineering. His scientific interests are in the fields of biotechnological applications of genetically modified microorganisms and diagnostic approaches utilizing molecular biotechnology tools.. The project dealing with heavy metal sensors for environmental analysis has continued more than ten years and extended into food and feed analysis recently.

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For further information about the work package 3, please contact leaderWP3@conffidence.eu