EVISA Newsletter

To follow publications related to chemical "speciation" is not an easy task, simply because the term "speciation" is used by different researchers with different meaning. Biologist use the term speciation for the evolutionary process by which populations evolve to become distinct species. IUPAC has defined, what chemist should call speciation, namely the distribution of an element amongst defined chemical species in a system. "Speciation analysis" then is the analytical activity to identify and/or measuring the quantity of one or more of these chemical species. Unfortunately, authors do not really stick to this rule and often use the term "speciation" when they have differentiated some fractions of the analyte element by a separation technique. Such behavior is leading to misinterpretation of findings and should be avoided. There are many papers published, in which authors claim to have found "hexavalent chromium" in biological materials such as foodstuffs when actually they have just analyzed a leachable fraction of chromium. Reviewers of such work should reject these manuscripts, in which authors talk about "speciation" when they simply performed "fractionation" (see the news below).

Toxicity is clearly related to species and not to elements, a fact that we have to stress against oversimplifications appearing in the media. A U.S. peer review panel lately agreed on the classification of antimony trioxide as a carcinogen. This voting could be significant in the EU, where the German REACH and CLP competent authority, Bundesanstalt für Arbeitsschutz und Arbeitsmedizin (BAuA), is to begin evaluating antimony trioxide – along with antimony sulfide and antimony metal – in March. Industry is concerned that the results could lead to stricter regulation (see the news below).

We frequently report about the global pollutant mercury that is present in our environment as different species that have different toxicity but are altogether a real health hazard for humans and animals. Researchers now discovered the world's largest amount of mercury trapped inside the frozen ground in permafrost regions. An alarming finding since the permafrost continues to thaw in the future due to climate change (see the news below).

Selenium is an essential element that occurs in some species that can reduce the toxicity of mercury. It also occurs in special selenoproteins. 200 years after its discovery, German scientists could demonstrate a specific and indispensable role of selenium for the survival of mammals. As an essential part of the enzym GPX4, selenium is protecting certain neurons from cell death by suppressing peroxide-induced ferroptosis (see the news below).