Your last carbon footprint.

Think of it as a last chance to reduce your carbon footprint. Soon there will be a range of greener options for your funeral – from being dissolved in chemicals to freeze-drying.


Shortages of land and changing attitudes mean traditional burials are in decline in many parts of the world. Around 75 per cent of people in the UK are cremated after they die, while in the US the figure has risen from 25 per cent in 2000 to approximately 35 per cent today.

Each cremation produces around 150 kilograms of CO2, according to a report by the UK’s Carbon Trust, a government-funded organisation that helps companies reduce their carbon emissions. Of this, 50 kilograms comes from burning the fuel used, the rest from burning the body and the coffin.

Cremations also produce toxic chemicals: a cubic metre of the exhaust gases can contain as much as 200 micrograms of mercury, largely from dental fillings, according to a review by José Domingo and Montse Mari at Rovira i Virgili University in Tarragona, Spain.  UK legislation is already in place requiring crematoriums to fit mercury-capturing filters by 2012.

One technology soon to be installed at a rest home in Florida produces less CO2 and eliminates mercury emissions, according to its developer. Resomation, based in Glasgow, UK, has developed a technique to dispose of a corpse by dissolving it in sodium hydroxide at 180 °C. A gas-fired steam boiler generates the heat required, and the procedure produces 66 kilograms of CO2 per body, says Sandy Sullivan, the company’s founder. The process has been approved for use in five US states, but not yet in the UK.

Freeze-drying bodies could reduce emissions even further, says another company, Cryomation, based in Woodbridge, UK. Its technique freezes a body to -195 °C using liquid nitrogen. Once brittle, the frozen body is turned into a powder and any metal removed. The remains are then dried in a vacuum and sterilised, says Richard Maclean of Cryomation. The powder can be buried in a biodegradable box, or composted and scattered as a fertiliser.

The process produces 50 kilograms of CO2 per body, says the Carbon Trust: heating the remains in the vacuum accounts for 35 kilograms, and producing and transporting the liquid nitrogen accounts for 15 kilograms.

Cryomation, which developed the technology with a team led by David Naseby at the University of Hertfordshire in Hatfield, UK, has already tested a prototype device on pig carcasses. A full-size prototype Cryomator is being built for trials later this year on human corpses.

Ian Hanson at Bournemouth University in the UK, a forensic archaeologist, points out that burying freeze-dried remains still uses up land. “Space would not be an issue if the powder was put to use, but is our society ready for our mortal remains to be utilised as fertiliser, or harrowed into crop fields?”

Via New Scientist