For the past 15 years the slender, bespectacled Abderrahmane has studied environmental trade and crime for the Institute for Security Studies (ISS), an African research and policy advisory organization based in South Africa. ISS papers showed how environmental degradation can fuel tensions among people and compromise security. But until a few years ago Abderrahmane had never heard of sand trafficking. He had been in Mali doing fieldwork on the drug trade when a source noted that most cannabis in Mali came from Morocco and that sand trafficking was also a major market in that country, with drug traffickers involved. “I think that when you talk about sand trafficking, most people would not believe it,” Abderrahmane says. “Me included. Now I do.”

Very few people are looking closely at the illegal sand system or calling for changes, however, because sand is a mundane resource. Yet sand mining is the world’s largest extraction industry because sand is a main ingredient in concrete, and the global construction industry has been soaring for decades. Every year the world uses up to 50 billion metric tons of sand, according to a United Nations Environment Program report. The only natural resource more widely consumed is water. A 2022 study by researchers at the University of Amsterdam concluded that we are dredging river sand at rates that far outstrip nature’s ability to replace it, so much so that the world could run out of construction-grade sand by 2050. The U.N. report confirms that sand mining at current rates is unsustainable.

The greatest demand comes from China, which used more cement in three years (6.6 gigatons from 2011 through 2013) than the U.S. used in the entire 20th century (4.5 gigatons), notes Vince Beiser, author of The World in a Grain. Most sand gets used in the country where it is mined, but with some national supplies dwindling, imports reached $1.9 billion in 2018, according to Harvard’s Atlas of Economic Complexity.