World faces an imminent crisis of phosphate fertilizer.

Byline: Shabbir Kazmi

The world faces an imminent crisis in the supply of phosphate, a critical fertilizer that underpins the world's food supply. Phosphate is an essential mineral for all life on earth and is added to farmers' fields in huge quantities. But rock phosphate is a finite resource and the biggest supplies are mined in politically unstable places, posing risks to the many countries that have little or no reserves.

Phosphate use has quadrupled in the last 50 years as the global population has grown and the date when it is estimated to run out gets closer with each new analysis of demand, with some scientists projecting that moment could come as soon as a few decades' time.

Researchers say humanity could only produce half the food it does without phosphate and nitrogen, though the latter is essentially limitless as it makes up almost 80% of the atmosphere.

"Phosphate supply is potentially a very big problem," said Martin Blackwell, at Rothamsted Research, an agricultural research centre in the UK, and lead author of a new study. "The population is growing and we are going to need more food."

At current rates of use, a lot of countries are set to run out of their domestic supply in the next generation, including the US, China and India, he said. Morocco and the Moroccan-occupied territory of Western Sahara host by far the largest reserve, with China, Algeria and Syria the next biggest, together representing more than 80% of global rock phosphate.

"In a few years' time, it could be a political issue with some countries effectively controlling the production of food by having control of rock phosphate supplies," Blackwell said. "There should be a lot more effort being put in so we are ready to deal with it. It is time to wake up. It is one of the most important issues in the world today."

Prof Martin van Ittersum, at Wageningen University in the Netherlands, said problems would begin before the mineral is exhausted: "Well before we run out of phosphate, the resource may become much more expensive."

Potential solutions include recycling phosphate from human sewage, manure and abattoir waste, new plant breeds that can draw the mineral from the soil more effectively and better soil tests to help end the over-application of the fertilizer.

Excessive use of phosphate is not only running down supplies but is also causing widespread pollution that leads to dead zones in rivers and seas. In 2015, research published in the journal Science...