Aquamation as a form of “Green Cremation”: A short Note

– Gayathri Gireesh*


The process of Aquamation (Alkaline Hydrolysis) captivated the interest the world community and sparked the debate around ‘green cremation’ when it was chosen as the funeral option by Archbishop Desmond Tutu who died on Dec. 26 2021[1]. Archbishop Desmond Tutu of South Africa was an anti-apartheid hero and Nobel Peace Prize winner and was renowned for his simple and modest lifestyle.[2] At his request, his body underwent the process of Aquamation which is considered to be a greener alternative to the burning of fossil fuels.[3]

The process of Aquamation has been around since 1888.[4] It was developed originally by a farmer named Amos Herbery Hanson to process animal carcasses into fertilizer. It was later used in labs to dispose of contaminated animal bodies. The first commercial Aquamation machine was installed at the Albany Medical College in 1993 to dispose of cadavers. The process continued to be used for this purpose in schools and hospitals.[5] Aquamation finds many uses in the treatment of medical waste[6]. Waste engineers like it because it handles so many kinds of waste and is robust. It operates at elevated temperatures but not nearly as high as an incinerator does, and air emissions are negligible.

Alkaline hydrolysis is related to the ancient technology of “rendering” animal carcasses. This was how people obtained animal fat for soap-making in centuries past. Compared to rendering, alkaline hydrolysis is more severe and breaks down much of the fat. It uses a more concentrated solution and a high temperature. The alkaline hydrolysis process is called “Resomation” and “Bio Cremation.” In this short note, the author discusses the process of Aquamation, its advantages and impact on the environment, fossil fuels, pollution and the legal and cultural aspects related to aquamation.


The Process of Aquamation

Hydro cremation was originally developed to safely dispose of animal remains after exposure to things like Mad Cow Disease. The technology has been used all over the world in laboratories for decades. With this less-than-pleasant origin, bio-cremation, or resomation as it is also known, has faced an uphill battle to gain popular acceptance.[7] During Aquamation A body is submerged in a solution of heated water and lye. After a matter of hours, everything but the bones dissolves into a liquid made up of water, salt and other components safe enough to go down the drain. The remaining bone fragments can be crushed into ash for scattering, burial or memorialization. Body donation programs such as the Mayo Clinic have long used the process, sometimes known as water cremation.[8]

Alkaline hydrolysis uses water, potassium hydroxide (a common ingredient in liquid soap) with relatively low heat (177 C, 350 F) and an inert liquid. Alkaline hydrolysis is also the way that all humans extract nutrients from food in our small intestines. The sterile by-product made up of peptides, sugars, amino acids, and soap is sent through municipal water treatment where it is filtered, purified, and recycled back to earth through aquifer.[9]

Village Memorial’s blog likens the process to an artificially sped-up version of what happens in nature as the body is decomposing. “By mimicking a body’s natural chemical process of decomposition, it breaks down the human chemical makeup of 65% Oxygen, 18% Carbon, 10% Hydrogen, 3% Nitrogen, 1.5% Calcium, 1% Phosphorus and 1.5% total of remaining additional elements, reducing CO2 emissions in the process.” Potassium hydroxide is the active chemical agent that is used, reducing tissues into amino acids, small peptides, sugars, nutrients, and soapy lather. In comparison, if left to occur naturally, total decomposition of a body can take up to 25 years rather than two to three hours.[10]


Advantages of Aquamation over traditional cremation

The traditional form of cremation uses fossil fuels. It is common knowledge that when oil, coal, and gas, called the Fossil fuels produce large quantities of carbon dioxide when burned. Carbon emissions trap heat in the atmosphere and lead to climate change.  Worldwide, the burning of fossil fuels, particularly for the power and transportation sectors accounts for about three-quarters of our emissions. The average global temperature has been increasing and arming above 1.5°C risking further sea level rise, extreme weather, biodiversity loss and species extinction, as well as food scarcity, worsening health and poverty for millions of people worldwide[11]

Considerable amount of greenhouse gas emissions is released during fuel burning cremation. It is also responsible for 16% of the UK’s mercury pollution (dental fillings), according to the Environment Agency. The industry has been told that all 650 crematoria must halve mercury emissions by 2012, but, ironically, one way to do this is to cremate at a higher temperature, thereby leading to more emissions.[12].In addition to harmless compounds such as water vapour, emissions include carbon dioxide, carbon monoxide, nitrogen oxide, sulphur dioxide, hydrogen chloride gas, hydrogen fluoride, mercury vapour, and also carcinogens are released. But then what is also true that when compared to yearly toxin release worldwide, crematoriums contribute only a very small fraction of harmful compounds or greenhouse gases [13] As the green burial movement has questioned the energy and resources required of these methods, another option has emerged: dissolving a body in water, or alkaline hydrolysis.[14]

The Funeral Consumers Alliance of Minnesota (FCA) refers to hydro cremation as “green cremations” and lists the following benefits of Aquamation over traditional Cremation[15]:

  • More than 75% reduction of carbon footprint.
  • Uses 1/8 the amount of energy of flame-based cremation.
  • Pacemakers and some other medical devices do not need to be removed prior to the process as with flame-based cremation.
  • Mercury from dental amalgam is contained and recycled, not vaporized.
  • Preserves 20+% more bone fragments than flame cremation.


Environmental Impacts of Traditional Cremation and Aquamation

Traditional cremation uses high-temp combustion in a specialized chamber to reduce human remains to ash. Hydro cremation uses water, pressure, heat and a highly basic (pH 14) additive. A specially designed machine dissolves soft tissues, leaving only bone fragments to be processed into ash.[16]

Proponents consider hydro cremation as a green burial option and a sustainable alternative to traditional embalming techniques and cremation alike. Critics cite concerns around the safety of flushing hydro-cremation effluent into the municipal water supply, as well as a perceived lack of respect for the human body. Because it’s such a new practice and used in so few places, the impact of widespread use in terms of pollution or public health is undetermined.[17]

Compared to burial or cremation, alkaline hydrolysis has several advantages in terms of environmental impact. This form uses less energy compared to cremation, which relies on natural or propane gas through combustion. Cremating also results in carbon dioxide (CO2) emissions that can contribute to greenhouse gases though less compared to various manufacturing and energy-creation processes.[18] The Urban space constraints can also be a factor as with burial space in urban areas worldwide becoming increasingly scarce and expensive. The Local administration needs to accommodate the space usage factor and hence this may be viable option. The debate on the Greenhouse gas emissions has made the environmental scientists vouch for Liquid cremation as it is gentler than a conventional one, and emits less greenhouse gases.[19]

According to UK-based firm Resomation, Aquamation uses five times less energy than fire, and reduces a funeral’s emissions of greenhouse gases by about 35%.Aquamation has no direct emissions of harmful greenhouse gases or mercury, does not burn fossil fuels, and uses less energy than flame-based cremation. It is a clean alternative and uses modern technology.[20]


Important Social, Cultural and Legal Aspects of Aquamation

The process of Aquamation offers some distinct “green” advantages in today’s environment and could potentially become a significant body-disposition option in the future. Provided that it overcomes two obstacles:

  • Public awareness due to Social and Cultural barriers
  • Regulatory, legal framework

Social and Cultural Barriers: The Environmentalist argument for a cleaner energy usage in cremation process has to be understood with the societal and religious aspects. Any society deep rooted in cultural and religious aspects, the benefits of such a cleaner technology can make its way, with being more effective when regulatory authorities can accommodate the socio religious factors. Performing last rites in either the form of burial or cremation is a very religious affair and involves a host of sentiments. Thus one of the major challenge in the acceptability of aquamation will be to overcome the social and cultural barriers through awareness and sensitization. The main concern in both religious and cultural practices is showing respect to the intrinsic dignity of the human body. In fact this was the issue raised at the New York State Catholic Conference when aquamation was proposed in 2012.[21] This religious resistance is rooted in the belief of “sacredness of the human body and its dignity”.[22]

Development of Regulatory Framework: Aquamation is authorised only in certain countries like Federal legislations in USA, Australia. Provinces in UK , Mexico, Canada. First developed in the early 1990s as a way to discard the bodies of animals used in experiments, the method was then used to dispose of cattle during the mad cow disease epidemic,. In the 2000s, US medical schools used Aquamation to dispose of donated human cadavers, before the it became a funeral industry. AH technologies use a heated (sometimes pressurized) solution of water and strong alkali to dissolve tissues, yielding an effluent that can be disposed through municipal sewer systems, and brittle bone matter that can be dried, crushed, and returned to the decedent’s family. Though AH is legal in eight US states, opposition to the technology remains strong. Opponents express concerns about public health and safety and about the dignity.[23]



The research so far on the process of aquamation is concentrated mostly on the chemical composition and industrial use such as sludge preparation and industrial residue. It is used both in agricultural sector for preparing fertilizers and in medical sector for disposal of human/animal bodies. The legal aspects of aquamation are less explored. Though some countries have enacted legislation on alkaline hydrolysis, the research on its environmental benefits is limited due to large amount of water required for the process. Most importantly, the hydrolysed water, though alkaline, is discharged into municipal water system and thus more scientific study is required in this field. Though carbon emission is very negligible in this process, the very fact that tons of gallons of water is required for the process is a matter of concern when used at mass scale. Religious sentiments and cultural barriers will play a significant role in adoption and acceptability of  aquamation as ‘green cremation’ method and genuine alternative to traditional mode of burials and cremation.

* Gayatrhi Gireesh, Advocate, Karnataka High Court

[1] Anita Chauhan & Daniela Fortino, What is Aquamation? A Sustainable Cremation Alternative Called Alkaline Hydrolysis, Eirene Blog, (last visited Jan. 24, 2022).

[2] Agence France-Presse, What is Aquamation? The Process Behind Desmond Tutu’s ‘Green Cremation’, The Guardian (Jan. 2, 2022),

[3] Anita Chauhan & Daniela Fortino, supra note 1.

[4] Id.

[5] Id.

[6] Alkanline Hydrolysis, Malsparo, (last visited Jan 24, 2022).

[7] Hydro Cremation v. Traditional Cremation, OneWorld Memorials, (last visited Jan. 24, 2022).

[8] Id.

[9] Id.

[10] Id.

[11] Fossil Fuels and Climate Change: The Facts, ClientEarth Communications (Nov. 11, 2020),

[12] Should I be Buried or Cremated , The Guardian ( Oct. 18, 2005),

[13] More about Cremation and Its Impact on the Environment, Cooperative Memorial Society, (last visited Jan. 24, 2022).


[15] Hydro Cremation v. Traditional Cremation, OneWorld Memorials, (last visited Jan. 24, 2022).

[16] Cremation: What is it?, OneWorld Memorials, (last visited Jan. 24, 2022).

[17]Hydro Cremation v. Traditional Cremation, OneWorld Memorials, (last visited Jan. 24, 2022).

[18] Id.

[19] Id.

[20] Id.

[21] NY Catholic Conference oposses ‘Chemical Digestion’ of Human Remains, Catholic News Agency (Mar. 25, 2012),

[22] Id.

[23] Philip R Olsen, Flush and Bone: Funeralizing Alkaline Hydrolysis in the United States, 39(5) Science Technology & Human Values 666 (2014).

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