Charcoal is attracting attention because its unique characteristics can be used in many ways. It has so many tiny cavities oriented in so many directions that one gram of charcoal has a surface area of about 250 m2. The cavities can attach different substances to their walls, then release them later. For example, they absorb moisture from humid air, then release it during dry conditions. This makes charcoal an excellent humidity regulator.

Charcoal has other benefits, too: it absorbs unpleasant room odors and harmful substances; it generates negative ions that are said to put people in a better frame of mind; and it exerts a far-infrared effect that supposedly improves blood circulation.

Researchers in Japan are examining these benefits, exploring new uses to develop innovative products like water purifiers (for drinking and bathing), agents to keep vegetables and other foods fresh, soil enhancers, humidity regulators for the walls and floors of homes, and deodorants.

Bamboo charcoal has more cavities, so it can absorb even more odors and moisture than wood charcoal. These advantages are increasingly being put to good use. Wood vinegar, a liquid made by cooling moist smoke from the kiln, is used for many purposes, from anti-bacterial agents and agricultural insecticides to deodorants, bath additives, and products to enhance health and beauty.

If you're thinking of using charcoal-based products in the home, you'll want to know what type and how much to use. Masuda Satoshi of Masuda-ya Co., Ltd., says, "binchotan charcoal is made at a very high temperature and has an alkaline effect. It's ideal for treating drinking water because it removes chlorine and other noxious substances. Also, it stays hard in the water, so it doesn't release any powdery material. If you put 50 to 60 grams in one liter of tap water, you'll increase the mineral content and soften the water, making excellent drinking water. If you use charcoal as a humidity regulator and odor absorber, you'll need 8 kg for a room area of around 10 to 13 m²."

Charcoal is environmentally friendly too-when you finish with it, just crush it into small pieces and let it go back to nature. Research continues, in the hope that more uses will be found.