As prices soar, Japan returns to human waste fertilizer

It's cheap, recycled, and has centuries of tradition: "shimogoe" or "fertilizer from a person's bottom" is finding new favor in Japan as Ukraine's war hikes the price of chemical alternatives.

As in several parts of the world, the use of "night soil" to fertilize crops was once common in Japan.

However, the advent of sewage systems and treatment facilities, as well as chemical fertilizers, saw it fall out of fashion.

About a decade ago, Japanese treatment facilities wondered if they could revive interest to avoid sewage sludge disposal -- a costly and potentially environmentally damaging process.

But enthusiasm was limited until the Russia-Ukraine war sent the cost of chemical fertilizers soaring.

That has been a bonanza for a facility in northern Japan's Tome, where sales of shimogoe were up 160 percent year-on-year by March 2023.

For the first time since the city began producing the fertilizer in 2010, it has sold out.

The demand is easy to explain, said facility vice president Toshiaki Kato.

"Our fertilizer is popular because it is cheap, and it is helping farmers cut soaring costs," he told AFP.

"It is also good for the environment."

Made of a combination of treated sewage sludge from septic tanks and human waste from cesspits, the fertilizer goes for USD 1.1 per 15 kilos.

That's about a tenth of the price of products made from imported raw materials.

In southwestern Japan's Saga too, officials report sales are up two to three times.

And dozens of tour groups from municipalities elsewhere in the country have visited, eager to replicate their program.