Tree produces 'nutty' ecological cleaner for laundry

BY SOPHIE KNIGHT STAFF WRITER

2011/08/18

From left to right: Hideaki Satoh, Kazumi Hosoya and Koichi Okano of Bitwin, with their "Laundry nuts" and "Eco nuts" products (Sophie Knight)The exclusive "Laundry nuts" brand sold by Satoh's company Students at a horticultural school in Toyama Prefecture grind "mukuroji," or soap nuts, as part of an experiment in 2003 to create natural pesticides. (Asahi Shimbun file photo)

If someone told you that you could clean your clothes with nuts, you'd probably think they were ... well, nuts.

Yet although a packet of salty peanuts probably won't get your whites spanking clean, the saponin-containing husks of "Soapnuts," can be an eco-friendly substitute for laundry detergent.

Looking at the waxy, lychee-like shells, it's hard to believe that they'll get sweat, dirt and stains out of clothes. But Hideaki Satoh, who sells the nuts through a Tokyo-based company, is effusive about their benefits.

"Not only are they kind to both your skin and the environment, they also rival any artificial detergent in terms of cleaning power," he says.

Satoh's company, Bitwin, sells an exclusive brand called "laundry nuts," which are grown in India, as well as the American "Eco-nuts" brand grown in Nepal that is becoming increasing popular overseas.

Both kinds can be used either inside a canvas bag in the washing machine, or else left to soak in a cup to produce a bubbly liquid to be poured on top of laundry.

Grown organically in India and Nepal, they produce no chemical effluent and therefore don't pollute the water supply like most chemical detergents. They're also hypoallergenic, making them highly suitable for sensitive skin and eczema sufferers. Satoh says that mothers who use cloth diapers are enthusiastic buyers.

"There's a growing interest in natural, nonchemical products in Japan, where many people are seeking ways to lead more ecological lifestyles, and conserve energy after the nuclear crisis in Fukushima," says Satoh, who launched the company last year after becoming interested in organic shampoos and skin-care products.

Although relatively unknown today, the soapnut tree, or "sapindus mukurossi," is actually native to Japan, and records indicate that it came into use in the Heian Period (794-1185) as a soap and disinfectant.

Many trees can still be found along riverbanks and in the grounds of temples and shrines, since they were places where communities could gather to share the harvest and use them for medical and sanitary use. As an added bonus, the seed inside can be roasted and eaten.

Although the tree is now known by the transliteration of its Latin name, "mukuroji," it used to be known as "enmeihi," or "long life skin." This is because the husk has antifungal and hygienic properties. It's also a natural insect repellent: you can keep the summer mosquitoes at bay by popping a few shells in the tub when you take a bath.

Sadly, their use declined in the 1800s as Japan opened up and began to import soap from abroad. They came back into use for a brief period following World War II, when the defeated country was destitute. Yet from the 1960s, imported chemical detergents became more popular, and consumers have never looked back.

"People have become convinced that a strong artificial smell and lots of bubbles are signs of cleaning power, which is not true," says Satoh. "It can be hard to convince people that these odd-looking husks can work."

He thinks this is a shame, as an environmentally friendly and freely available zero-carbon resource was swapped for harsh chemical compounds that can damage the skin and pollute groundwater.

"In the future I'd really like to encourage the planting and harvesting of soapnut trees throughout Japan, so that our carbon footprint is decreased and we don't have to import them from the Himalayas," he says.

While the existing trees in Japan could effectively provide free detergent, the few that are left are mostly on private property. Fortunately, Satoh's products are still easy on the pocket.

A small handful of husks inside a canvas bag can be used for up to 13 washes, meaning that a larger 250g bag, priced at 1,000 yen ($13), is good for more than 100. Cheap, little carbon footprint, and ecological-- what's the catch?

According to Satoh, there isn't one.

"Sometimes, finding solutions to modern problems requires a look back into the past," he explains. "Tradition can teach you a lot."

To buy soapnuts, visit http://item.rakuten.co.jp/venustokyo/c/0000000231#top