Professor of Bio-geo-nanochemistry at the University of Grenoble, France, he got his PhD from the University of California. He is now affiliate at LBNL (USA), Adjunct Prof. at University of Waterloo (Canada) and University of Swansea (UK). He co-created the Environment Geochemistry team and brought it into the global spotlight by performing research at drastically different scales: (i) large scale multidisciplinary field investigations (on the fate of toxics such as mercury in Amazonian forest and arsenic in SE Asian deltas) and (ii) molecular level spectroscopic investigations, particularly at ESRF synchrotron facilitiy, with a special focus on the chemistry of natural and engineered nanoparticles and chemical issues of importance to human health and to redox active essential trace elements.