Isotopic fractionation – Chapter 3

I. Why do isotopes fractionate ? Isotope fractionation is characterized by a difference in reactivity of isotopes during a chemical reaction resulting in a different isotopic ratio between product and reactant. These fractionations are caused by numerous processes (change in degree of oxidation, adsorption, evaporation, etc.) and are often complex to apprehend, describe or predict. […]

Isotopes as tracers – Chapter 2

Isotopes have many applications in the environment. For example, the isotopes of carbon (14C) are widely used in recent dating. Oxygen (18O) isotopes can be used to reconstruct climates and temperatures when analyzed in ice or the shells of small marine animals. Tritium, the hydrogen isotope seen in the previous lesson, can be used to […]

What is an isotope ? Chapter 1


Isotopes are very effective tools in environmental studies, particularly to trace pollutions. Before we look at its various applications and uses, it is important to look at the basics: what is an isotope? I. What is an atom ? Atoms, which constitute matter, are mainly composed of empty space (more than 99%). However, they are […]