Project Details Compilation of the variation of the isotopic composition of the elements via crowdsourcing

Project No.:
Start Date:
15 December 2014
End Date:


The scientific and industrial research community is facing an increasing need to establish natural ranges of the isotopic composition of different sample types in order to be able to evaluate isotopic data obtained in the individual laboratories on a global scale. The purpose of this project is ‘data collection on a global scale’ via modern web-based interfaces and to compile ranges of isotope abundance ratios of the following elements: B, Cd, Hg, Mg, Mo, Sr, and U. The scientific community has identified these elements as important elements with a significant variation in their isotopic composition both in nature and synthetic materials.

As the project aims at the development and setup of a web based interface for collecting and disseminating isotopic data, the focus of this first step was set on a selection of elements. It is evident that other elements are of high interest, as well. Nonetheless, the number of elements is kept limited within this stage of the project in order to ensure quality control. Depending upon the success of the project, the list of elements will be extended to elements such as Li, Ca, Fe, Ni, Cu, Zn, Se within this project or in a future continuation and finally to the whole set of potential elements as the tools can be easily adapted once they are in action.


The scientific community faces an increasing number of data published on isotope-abundance ratios and corresponding atomic weight variations as well as mole fractions in ‘normal’ materials. This challenges the user in data reviewing and evaluating, thus limiting appropriate data handling and international transparency. As a consequence, a compilation of data based on highest quality standards reviewed by independent experts in the field is of utmost importance.

At present, data collection of the isotopic composition of elements in natural and synthetic material is accomplished by a selected group of scientist (currently undertaken by the SIAM (Subcommittee on Isotopic Abundance Measurements)/CIAAW task groups). During this process of data collection, some data is not accessible and some data is certainly overlooked facing the continuously increasing number of papers providing isotopic data.

The creation of a web-based input interface where scientists can submit data on isotopic abundance ratios (including additional information e.g. on the sample, the measurement or the uncertainty) will tremendously augment, accelerate and improve data collection. The values submitted will be subsequently subject to a review process via a selected group of experts (nominated by CIAAW) in order to assure quality control and prove the metrological quality of the data. All data will be retained in the database but rated by their metrological quality (based on the criteria applied in the Table of Isotopic Compositions of the Elements) allowing for user-defined deselection of results. The web-based interface will allow for source-specific, tailor-made download of isotopic data dependent on the user’s interests via selection-tick boxes (e.g. by element, sample type, geographic area), thus allowing for topic specific creation of individual diagrams released by the Subcommittee on Natural Isotopic Fractionation (SNIF). CIAAW provides the required expertise for this project as responsible group of specialists on isotope abundance and atomic weight data evaluation and review. The project bears great potential to source a substantial quantity of data.


This project is co-supported by the Analytical Chemistry Division (Div V) and the Chemistry and the Environment Division (VI).

Sep 2017 update – A web-interface for crowd-sourcing of published data on atomic weights and isotopic abundances was programmed, established and tested by the task group members via The submission of published data is currently possible for hydrogen, helium, lithium, boron, carbon, nitrogen, oxygen, neon, magnesium, silicon, sulfur, chlorine and argon.

Taylor-made SNIF diagrams are currently available for hydrogen, lithium, carbon, nitrogen, oxygen, magnesium, silicon, sulfur, chlorine, bromine, thallium via

In the current test phase, selected stakeholders are invited to test the database by submitting published data, especially on B, Cd, Mo, Se, Sr, U.

Page last updated 13 Sep 2017