VANCOUVER, British Columbia, Dec 1 (Reuters Life!) - Worried you haven’t been green enough in life? Don’t let death come in the way of a more eco-friendly you.

From coffins made of recycled cardboard to saying no to embalming chemicals that seep into the soil, people are increasingly searching for ways to make their final resting place a more environmentally-friendly one.

Now cremation, the choice today of a third of Americans and more than half of Canadians, is getting a green make-over.

A standard cremation spews into the air about 400 kilograms (880 pounds) of carbon dioxide -- a greenhouse gas blamed for global warming -- along with other pollutants like dioxins and mercury vapor if the deceased had silver tooth fillings.

On top of that each cremation guzzles as much energy, in the form of natural gas and electricity, as a 500-mile (800 kilometer) car trip.

Enter alkaline hydrolysis, a chemical body-disposal process its proponents call “bio-cremation” and say uses one-tenth the natural gas of fire-based cremation and one-third the electricity.

C02 emissions are cut by almost 90 percent and no mercury escapes as fillings and other metal objects, such as hip or knee replacements, can be recovered intact and recycled.

"The target audience are those people who buy organic salmon rather than farmed salmon. Those that buy a hybrid rather than a regular car," said Paul Rahill, president of the cremation division of Matthews International Corp MATW.O.

The Pittsburgh, Pennsylvania-based company that makes caskets and other funeral products is planning the world’s first commercial launch of human alkaline hydrolysis in January at a funeral home in St Petersburg, Florida.

The technique is not new but has only been used to dispose of laboratory animals and medical research cadavers at a few institutions.

Its commercial use has been held up partly because of its cost -- the equipment is four times as expensive as that of traditional cremation -- and because state and provincial legislation may need to be changed, especially laws governing what can be disposed of in the water system.

Overcoming peoples’ squeamishness when they hear the process described, what Rahill calls the ‘ick’ factor, is also an obstacle.

The Catholic Church in parts of the United States has objected, saying the practice “is not a respectful way to dispose of human remains”.

In alkaline hydrolysis the body is submerged in water in a stainless steel chamber. Heat, pressure and potassium hydroxide, chemicals used to make soap and bleach, are added to dissolve the tissue.

Two hours later all that’s left is some bone residue and a syrupy brown liquid that is flushed down the drain. The bones can be crushed and returned to the family as with cremation.

“This is the first new alternative to come into the (cremation) market in over 100 years,” said Allen Bessel, president of Transition Science, a Toronto-based company that owns the exclusive rights to the process in Canada. It is targeting a commercial launch next spring.

“It is very quiet, there is no noticeable odor that comes from it and there is no emission. The concerns of area residents would be much less if (an alkaline hydrolysis machine) was being installed than if a crematorium was built,” Bessel said.

Although Rahill says the public response has been mostly positive, an attempt to introduce human alkaline hydrolysis in New York state a couple of years ago was opposed by the Catholic Church and others, and the bill was dropped.