The good results should enhance consumers' confidence, as maximum levels of lead, cadmium and total mercury in seafood are regulated by EU law and it has been proven that most participants are able to correctly measure them. In addition, this comparison has highlighted other issues, such as the apparent dependency of the measurements of inorganic arsenic on the type of food tested.
Excessive intake of heavy metals may lead to a decline in mental, cognitive and physical health. A particular concern is potential developmental defects in children exposed in utero. From a toxicological point of view, the chemical form in which the metal is ingested plays a significant role. For example, methylmercury is much more toxic than inorganic mercury compounds, whilst inorganic arsenic is more toxic than the organic species of arsenic.
The interlaboratory comparison
The interlaboratory comparison was organised in support of the European Co-operation for Accreditation (EA), the Asia Pacific Laboratory Accreditation Cooperation (APLAC) and the national reference laboratories associated to the European Union Reference Laboratory for Heavy Metals in Feed and Food.
Participants were asked to report both the measured value of each heavy metal in question in the sample and the uncertainties associated with those measurements. The results were scored according to international standards .
The outcome of the exercise was generally positive. All of the 57 laboratories that registered reported results. The share of satisfactory scores ranged between 80% and 96% (Table 1 in pdf link). Participants tended to underestimate the content of total arsenic, and to a lesser extent total cadmium. The distribution of the participating laboratories by country is shown in Figure 2 in pdf link.
Contrary to a previous exercise (IMEP-107 on total and inorganic arsenic in rice), the values reported for inorganic arsenic showed a large spread. Interestingly, this indicates that the matrix (in this case, seafood), has a major influence on the analytical determination of inorganic arsenic. This is a crucial consideration for legislators, because specifying single maximum level of arsenic in food would appear to be unfeasible.
In Europe, maximum levels for lead, cadmium and total mercury in food are laid down in legislation , varying from 0.5 to 1.0 mg. per kg. for different seafood. No maximum level exists for the methylmercury form of mercury, as its measurement requires specific analytical equipment not routinely present in testing laboratories. However, methylmercury is the main source of human intake of mercury in fish and fishery products, and is important due to its high toxicity compared to inorganic mercury.
No maximum levels for arsenic have been laid down in European legislation either, due to a lack of information about reliable analytical methods for determining inorganic arsenic in different food commodities, and measurement values of inorganic arsenic are generally believed to be method-dependent.
The interlaboratory comparison was, therefore, extended to include methylmercury and inorganic arsenic, in order to investigate the issues that laboratories encounter in measuring these substances.
JRC-IRMM and the EU Reference Laboratories
The Institute for Reference Materials and Measurements (IRMM) is one of the seven institutes of the Joint Research Centre (JRC) which is a Directorate-General of the European Commission.
It operates four European Union Reference Laboratories (EU-RL), including the EU-RL for heavy metals in feed and food. The EU-RLs are analytical laboratories designated by EU legislation and which are an integral part of European risk management system. Their duties include setting up EU-wide standards for reliable testing methods, organising comparative tests, training analysts from national laboratories and providing scientific and technical assistance to the European Commission.
JRC-IRMM also operates the International Measurement Evaluation Programme (IMEP®). It organises interlaboratory comparisons in support to EU policies. Many of the interlaboratory comparisons are open to all laboratories that wish to participate, but some are restricted to, for example, national reference laboratories. Proficiency tests are normally carried out only on request of another Commission department or agency. Some comparisons are run to certify reference materials and validation studies are organised regularly to validate analysis methods.
Interlaboratory comparison report: "IMEP-30: Total arsenic, cadmium, lead, and mercury, as well as methylmercury and inorganic arsenic in seafood": http://irmm.jrc.ec.europa.eu/news/Documents/IMEP_30_report.pdfContacts
David Anderson, JRC-IRMM Communication officer: email@example.com
Elena Gonzalez Verdesoto | EurekAlert!
Team discovers how bacteria exploit a chink in the body's armor
20.01.2017 | University of Illinois at Urbana-Champaign
Rabies viruses reveal wiring in transparent brains
19.01.2017 | Rheinische Friedrich-Wilhelms-Universität Bonn
An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...
Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...
Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.
While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...
Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales
Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...
Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.
As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...
19.01.2017 | Event News
10.01.2017 | Event News
09.01.2017 | Event News
20.01.2017 | Awards Funding
20.01.2017 | Materials Sciences
20.01.2017 | Life Sciences