This work was published as an article in Nature Communications, and I wrote an article explaining our findings for The Conversation. I also contributed to journalism published in parallel in the Financial Times, Le Monde, as well as a writeup of our collaboration for Lighthouse Reports.
This work also received coverage at BBC News, Bloomberg, Radio France Internationale, The Canary, Radio-télévision belge de la Communauté française, Princeton University, and The University of Wisconsin - Madison, among others.
While working on this project, I was continually asked why in the world I was working with a group focused on science and policy questions related to nuclear weapons and energy. I am a geologist. What was I contributing to the field where physicists and engineers are the go-to experts?
In order for any group to build a nuclear technology, there first must be a source of uranium ore. So, if you want to craft relevant policies to limit or eliminate nuclear weapons, the first point in understanding nuclear programs is a mineral deposit.
The geological stories may not be the first ones we reach for when we think about the key moments of the nuclear age, but these technologies begin as rocks. The first picture in many heads when prompted about the Manhattan Project may be J. Robert Oppenheimer with reflections of a mushroom cloud in his eyes. However, that effort would have stalled significantly if Edgar Sengier hadn’t preemptively stockpiled 1,200 tonnes of uranium ore from the Democratic Republic of Congo (DRC) in a warehouse on Staten Island, New York.
The DRC also is where my work in nuclear science and policy starts by way of a different element. A region in southern DRC known as the Copperbelt currently is the source of over two-thirds of our world’s cobalt supplies that are used in batteries that power smart phones, laptops, and electric vehicles.
My work on this project illustrates a scenario that looks fairly concerning when you think at the intersection of a few pieces of knowledge. This immensely productive industry is extracting cobalt from minerals known to contain elevated levels of uranium, and uranium’s chemical behavior is such that it remains in the crude products that are exported from the DRC for further cobalt refining elsewhere (mostly in China), unless deliberate steps are taken to remove it.
Discussions of uranium removal from DRC cobalt only began in 2023, but the industry has been surging since 2000. So, have consequential quantities of uranium been shipped out of the DRC as part of the cobalt trade and remain unaccounted for?
I encourage you to read the scientific and journalistic pieces linked above to see how we used geological modeling, trade data, imports analysis, and source interviews to arrive at a clear answer of ‘Yes’. We estimate that several thousand tonnes of uranium have been exported in cobalt products over the last two and a half decades, and the vast majority of this material has gone to China and remains outside of official records as to how it was used or discarded. To give a sense of scale for this estimate, approximately 3.3 tonnes of natural uranium are required to make a nuclear warhead, and so we are easily talking about the possibility of hundreds of weapons worth.
This project was built on an innovative partnership between scientists and investigative journalists working together on a public interest research investigation. I, along with Sébastien Philippe collaborated with journalists and editors from Lighthouse reports and the Financial Times.