Soil group urges use of sewage fertiliser

The Soil Association, which certifies all of the UK's organic produce, is calling for a change in the law in a new report on tightening supplies of fertiliser.

In its study A Rock and a Hard Place it says supplies of phosphate rock are running out faster than previously thought and that declining supplies and higher prices of the resource pose a threat to the world's food security.

The association said a "radical rethink" was required to become less reliant on phosphate rock-based fertilisers, prompting its controversial call for EU organic regulations to be relaxed to permit the use of human sewage.

Human waste is rich in natural phosphates and would be useful in fertilising agricultural land, it said.

It states: "Globally only 10 per cent of human waste is returned to agricultural soils. Urine alone contains more than 50 per cent of the phosphorus excreted by humans."

It also recommends eating less meat as means of reducing the demand for mined phosphate, claiming vegetable-based production is more efficient in its use of phosphorus then livestock production.

Worldwide some 158 million tonnes of phosphate rock is mined every year with supplies estimated by the Soil Association to become "increasingly scarce and more expensive".

China has now restricted phosphate exports while the USA has stopped it altogether.

The current price of phosphate rock is approximately twice that of 2006, the report adds.

"This critical issue is missing from the global policy agenda – we are completely unprepared to deal with the shortages in phosphorus inputs, the drop in production and the hike in food prices that will follow.

"Without fertilisation from phosphorus it has been estimated that wheat yields could more then halve in coming decades."