Alkaline hydrolysis (also called biocremation, resomation, flameless cremation, aquamation or water cremation) is a process for the disposal of human and pet remains using

lye Lye is the common name of various alkaline solutions, including soda lye (a solution of sodium hydroxide) and potash lye (a solution of potassium hydroxide). Lyes are used as cleaning products, as ingredients in soapmaking, and in various other c ...

and heat; it is alternative to

burial Burial, also known as interment or inhumation, is a method of final disposition whereby a dead body is placed into the ground, sometimes with objects. This is usually accomplished by excavating a pit or trench, placing the deceased and objec ...

cremation Cremation is a method of Disposal of human corpses, final disposition of a corpse through Combustion, burning. Cremation may serve as a funeral or post-funeral rite and as an alternative to burial. In some countries, including India, Nepal, and ...

, or

sky burial Sky burial (, "bird-scattered") is a funeral practice in which a human corpse is placed on a mountaintop to decompose while exposed to the mahābhūta, elements or to be eaten by Scavenger, scavenging animals, especially vultures, bears and j ...

Process

The process is based on

alkaline hydrolysis Hydrolysis (; ) is any chemical reaction in which a molecule of water breaks one or more chemical bonds. The term is used broadly for substitution, elimination, and solvation reactions in which water is the nucleophile. Biological hydrolysis ...

: the body is placed in a pressure vessel which is then filled with a mixture of water and

potassium hydroxide Potassium hydroxide is an inorganic compound with the formula K OH, and is commonly called caustic potash. Along with sodium hydroxide (NaOH), KOH is a prototypical strong base. It has many industrial and niche applications, most of which utili ...

, and heated to a temperature of around at an elevated pressure which precludes boiling. The body is efficiently broken down into its chemical components, (completely disintegrating its DNA), a process which takes approximately four to six hours. Also, lower temperatures () and pressures may be used such that the process takes 14 to 16 hours. At the start, the mixture is very alkaline, with a pH level of approximately 14; this drops to approximately 11 by the end, but the exact value depends on the total operation time and the amount of fat in the body. The result is a quantity of green-brown tinted liquid (containing

amino acids Amino acids are organic compounds that contain both amino and carboxylic acid functional groups. Although over 500 amino acids exist in nature, by far the most important are the Proteinogenic amino acid, 22 α-amino acids incorporated into p ...

peptides Peptides are short chains of amino acids linked by peptide bonds. A polypeptide is a longer, continuous, unbranched peptide chain. Polypeptides that have a molecular mass of 10,000 Dalton (unit), Da or more are called proteins. Chains of fewer t ...

sugars Sugar is the generic name for Sweetness, sweet-tasting, soluble carbohydrates, many of which are used in food. Simple sugars, also called monosaccharides, include glucose, fructose, and galactose. Compound sugars, also called disaccharides ...

and

salts In chemistry, a salt or ionic compound is a chemical compound consisting of an assembly of positively charged ions ( cations) and negatively charged ions (anions), which results in a compound with no net electric charge (electrically neutral). ...

) and soft, porous white bone remains (

calcium phosphate The term calcium phosphate refers to a family of materials and minerals containing calcium ions (Ca2+) together with inorganic phosphate anions. Some so-called calcium phosphates contain oxide and hydroxide as well. Calcium phosphates are white ...

) easily crushed in the hand (although a cremulator is more commonly used) to form a white-colored dust. The "ash" can then be returned to the

next of kin A person's next of kin (NOK) may be that person's spouse A spouse is a significant other in a marriage. A female spouse is called a wife while a male spouse is called a husband. Married The legal status of a spouse, and the specific righ ...

of the deceased. The liquid is disposed of either through the sanitary sewer system, or through some other method, including use in a garden or green space. To dispose of of biomass, approximately of water are used, resulting in of effluent, which carries a dried weight (inorganic and mineral content) of (approximately 2% of original weight). This alkaline hydrolysis process has been championed by a number of ecological campaigning groups, for using 90 kWh of electricity, one-quarter the energy of flame-based

, and producing less

carbon dioxide Carbon dioxide is a chemical compound with the chemical formula . It is made up of molecules that each have one carbon atom covalent bond, covalently double bonded to two oxygen atoms. It is found in a gas state at room temperature and at norma ...

and pollutants. It is being presented as an alternative option at some British crematorium sites. , about 1,000 people had chosen this method for the disposal of their remains in the

United States The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 ...

. The operating cost of materials, maintenance, and labor associated with the disposal of of remains was estimated at $116.40, excluding the capital investment cost of equipment. Alkaline hydrolysis has also been adopted by the pet and animal industry. A handful of companies in North America offer the procedure as an alternative to pet cremation. Alkaline hydrolysis is also used in the agricultural industry to sterilize animal carcasses that may pose a health hazard, because the process inactivates viruses, bacteria, and

prion A prion () is a Proteinopathy, misfolded protein that induces misfolding in normal variants of the same protein, leading to cellular death. Prions are responsible for prion diseases, known as transmissible spongiform encephalopathy (TSEs), w ...

s that cause

transmissible spongiform encephalopathy Transmissible spongiform encephalopathies (TSEs), also known as prion diseases, are a group of progressive, incurable, and fatal conditions that are associated with the prion hypothesis and affect the brain and nervous system of many animals, in ...

History

The process was patented by Amos Herbert Hobson in 1888 as a method to process animal carcasses into plant food. In 2005, Bio-Response Solutions designed, sold, and installed the first single cadaver alkaline hydrolysis system at the

Mayo Clinic Mayo Clinic () is a Nonprofit organization, private American Academic health science centre, academic Medical centers in the United States, medical center focused on integrated health care, healthcare, Mayo Clinic College of Medicine and Science ...

, where it was still in use as of 2019. In 2007, a Scottish biochemist, Sandy Sullivan, started a company making the machines, and calling the process (and company) Resomation.

Religious views

Christian A Christian () is a person who follows or adheres to Christianity, a Monotheism, monotheistic Abrahamic religion based on the life and teachings of Jesus in Christianity, Jesus Christ. Christians form the largest religious community in the wo ...

countries and cultures, cremation has historically been discouraged and viewed as a desecration of God's image, and as interference with the resurrection of the dead taught in scripture. It is now acceptable to some denominations.

Desmond Tutu Desmond Mpilo Tutu (7 October 193126 December 2021) was a South African Anglican bishop and theologian, known for his work as an anti-apartheid and human rights activist. He was Bishop of Johannesburg from 1985 to 1986 and then Archbishop ...

, former

Anglican Archbishop of Cape Town The Diocese of Cape Town is a diocese of the Anglican Church of Southern Africa (ACSA) which presently covers central Cape Town, some of its suburbs and the island of Tristan da Cunha, though in the past it has covered a much larger territory. T ...

, was aquamated, per his wish. The

Eastern Orthodox Church The Eastern Orthodox Church, officially the Orthodox Catholic Church, and also called the Greek Orthodox Church or simply the Orthodox Church, is List of Christian denominations by number of members, one of the three major doctrinal and ...

does not allow cremation. The

Roman Catholic Church The Catholic Church (), also known as the Roman Catholic Church, is the List of Christian denominations by number of members, largest Christian church, with 1.27 to 1.41 billion baptized Catholics Catholic Church by country, worldwid ...

allows

of bodies as long as it is not done in denial of the beliefs in the sacredness of the human body or the resurrection of the dead. In 2008, Renée Mirkes published the first Catholic moral analysis of alkaline hydrolysis. He argued that it is morally neutral and may be an alternative to burial on similar grounds to cremation. However, the Catholic Church in the United States does not approve of alkaline hydrolysis as a method of final disposal of human remains. In 2011, Donald Cardinal Wuerl, Archbishop of Washington and then chairman of the Committee on Doctrine of the United States Conference of Catholic Bishops (USCCB), determined it "unnecessarily disrespectful of the human body." The Archdiocese of St. Louis explained that it was considered this way because the Church took concern with the final disposal of the liquid solution, which is typically to the sewer system. This was considered disrespectful of the sanctity of the human body. Additionally, when alkaline hydrolysis was proposed in New York state in 2012, the New York State Catholic Conference condemned the practice, stating that hydrolysis does not show sufficient respect for the teaching of the intrinsic dignity of the human body.

Judaism Judaism () is an Abrahamic religions, Abrahamic, Monotheism, monotheistic, ethnic religion that comprises the collective spiritual, cultural, and legal traditions of the Jews, Jewish people. Religious Jews regard Judaism as their means of o ...

forbids cremation as it is not in line with the religion’s teachings of respect and dignity for humans, who are believed by the religion to be created in God’s image.

Islam Islam is an Abrahamic religions, Abrahamic monotheistic religion based on the Quran, and the teachings of Muhammad. Adherents of Islam are called Muslims, who are estimated to number Islam by country, 2 billion worldwide and are the world ...

also forbids cremation of the deceased. Both religions are likely to reject alkaline hydrolysis as they believe that the body must be laid to rest through burial in order to prepare for the afterlife. The

Baháʼí Faith The Baháʼí Faith is a religion founded in the 19th century that teaches the Baháʼí Faith and the unity of religion, essential worth of all religions and Baháʼí Faith and the unity of humanity, the unity of all people. Established by ...

, like other Abrahamic religions, discourages cremation of the deceased. The human body is seen as having to be treated with respect, and merely wrapped in a shroud before burial no further than an hour from the place of death.

Sikhism Sikhism is an Indian religion and Indian philosophy, philosophy that originated in the Punjab region of the Indian subcontinent around the end of the 15th century CE. It is one of the most recently founded major religious groups, major religio ...

Hinduism Hinduism () is an Hypernymy and hyponymy, umbrella term for a range of Indian religions, Indian List of religions and spiritual traditions#Indian religions, religious and spiritual traditions (Sampradaya, ''sampradaya''s) that are unified ...

, and

Buddhism Buddhism, also known as Buddhadharma and Dharmavinaya, is an Indian religion and List of philosophies, philosophical tradition based on Pre-sectarian Buddhism, teachings attributed to the Buddha, a wandering teacher who lived in the 6th or ...

each place theological emphasis on the complete immolation of the corpse. Native Hawaiians consider aquamation a way to approximate their traditional burial ritual, which involves removing the bones (iwi) cleanly from the flesh using a beachside underground oven (imu), wrapping the bones, and hiding them. The use of an ''imu'' on human bodies is no longer allowed, but aquamation may offer an alternative as it produces similarly clean bones.

Legal status

Australia

Aquamation based in

New South Wales New South Wales (commonly abbreviated as NSW) is a States and territories of Australia, state on the Eastern states of Australia, east coast of :Australia. It borders Queensland to the north, Victoria (state), Victoria to the south, and South ...

is the only company to provide alkaline hydrolysis in Australia, with the remains being used as fertilizer on plantation forests, due to difficulty with obtaining permits from

Sydney Water Sydney Water, formally, Sydney Water Corporation, is a Government of New South WalesState-owned corporation, owned statutory authority, statutory corporation that provides potable drinking water, wastewater and some stormwater services to Sydney ...

New Zealand

Water Cremation Aotearoa has been an advocate for bringing the service to

New Zealand New Zealand () is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and List of islands of New Zealand, over 600 smaller islands. It is the List of isla ...

(Aotearoa). Bell, Lamb and Trotter, in

Christchurch Christchurch (; ) is the largest city in the South Island and the List of cities in New Zealand, second-largest city by urban area population in New Zealand. Christchurch has an urban population of , and a metropolitan population of over hal ...

, started to offer water cremation in June 2025.

Belgium

Flanders

The Flemish minister of Interior Administration

Bart Somers Bartolomeus Jozef Lodewijk Rosalia "Bart" Somers (born 12 May 1964 in Mechelen) is a Belgian, Flemish politician. He is currently the mayor of Mechelen. In 2017, Bart Somers was awarded 2016 World Mayor Prize as recognition for his outstandin ...

asked in September 2021 the opinion of an advisory

bioethics Bioethics is both a field of study and professional practice, interested in ethical issues related to health (primarily focused on the human, but also increasingly includes animal ethics), including those emerging from advances in biology, me ...

committee on resomation. The advice, received in November 2021, saw no objections.

Canada

Saskatchewan Saskatchewan is a Provinces and territories of Canada, province in Western Canada. It is bordered on the west by Alberta, on the north by the Northwest Territories, on the east by Manitoba, to the northeast by Nunavut, and to the south by the ...

approved the process in 2012, becoming the first province to do so.

Quebec Quebec is Canada's List of Canadian provinces and territories by area, largest province by area. Located in Central Canada, the province shares borders with the provinces of Ontario to the west, Newfoundland and Labrador to the northeast, ...

and

Ontario Ontario is the southernmost Provinces and territories of Canada, province of Canada. Located in Central Canada, Ontario is the Population of Canada by province and territory, country's most populous province. As of the 2021 Canadian census, it ...

have also legalized the process. A funeral home in

Granby, Quebec Granby () is a town in the southwestern region of Quebec east of Montreal. According to the latest statistics from the 2021 Canadian census, 2021 Canadian Census, Granby has a population of 69,025. It is the administrative center of La Haute-Yam ...

, was the first in the province to receive an alkaline hydrolysis machine.

Ireland

In 2023, water cremation became available in Ireland, making it the first country in Europe to offer this form of burial. When the process is complete, the remaining water undergoes further treatment to ensure that it is completely sterile. Analysis is then completed to ensure Water Authority standards are met. At this stage, the water can be recycled back to the Local Authority water treatment plant.

Mexico

Since 2019, Grupo Gayosso offers alkaline hydrolysis in

Baja California Baja California, officially the Free and Sovereign State of Baja California, is a state in Mexico. It is the northwesternmost of the 32 federal entities of Mexico. Before becoming a state in 1952, the area was known as the North Territory of B ...

The Netherlands

In May 2020, the Health Council of the Netherlands issued an advisory report on the admissibility of new techniques of disposing of the dead. The Council proposed a framework to assess alkaline hydrolysis. It concluded that alkaline hydrolysis is safe, dignified and sustainable. In addition to alkaline hydrolysis, the council also considered human composting as a technique to dispose bodies yet concluded that too little is known about composting and hence it cannot be assessed whether this technique fulfills the conditions. Taking into account the council's recommendations, the Ministry of the Interior and Kingdom Relations prepared a law proposal to amend the Corpse Disposal Act. Once the proposed law has been submitted to the Parliament, the democratic process to admit alkaline hydrolysis as body disposal technique can be commenced.

South Africa

In November 2019, Avbob introduced aquamation in South Africa, following the mutual assurance society's recent introduction of the alkaline hydrolysis process at its Maitland agency in Cape Town. Aquamation has been legal in South Africa since then. Following his death in December 2021 the body of

Archbishop Desmond Tutu Desmond Mpilo Tutu (7 October 193126 December 2021) was a South African Anglican bishop and theologian, known for his work as an anti-apartheid and human rights activist. He was Bishop of Johannesburg from 1985 to 1986 and then Archbishop o ...

was aquamated.

United Kingdom

A public crematorium operated by

Sandwell Metropolitan Borough Council Sandwell Metropolitan Borough Council, or Sandwell Council, is the local authority of the Metropolitan Borough of Sandwell in the West Midlands, England. It is a metropolitan borough council and provides the majority of local government servic ...

Rowley Regis Rowley Regis ( ) is a town and former municipal borough in Sandwell in the county of the West Midlands (county), West Midlands, England. It forms part of the area immediately west of Birmingham known as the Black Country and encompasses the fou ...

, central England, was the first to receive

planning permission Planning permission or building permit refers to the approval needed for construction or expansion (including significant renovation), and sometimes for demolition, in some jurisdictions. House building permits, for example, are subject to buil ...

to offer the process but in March 2017, the local water utility,

Severn Trent Water Severn Trent plc is a water company based in Coventry, England. It supplies 4.6 million households and business across the Midlands and Wales. It is traded on the London Stock Exchange and a constituent of the FTSE 100 Index. Severn Trent, the ...

, refused the council's application for a "trade effluent permit" because there was no

water industry The water industry provides drinking water and wastewater services (including sewage treatment) to residential, commercial, and industrial sectors of the economy. Typically public utilities operate water supply networks. The water indust ...

standard regulating the disposal of liquefied human remains into sewers. In July 2023, the BBC reported that “ ter cremation is set to be made available for the first time in the UK.”

United States

Alkaline hydrolysis as a method of final disposition of human remains is legal in 24 states . Legislation is pending in New Jersey, New York, Ohio, Pennsylvania, and Virginia. The process was legal in

New Hampshire New Hampshire ( ) is a U.S. state, state in the New England region of the Northeastern United States. It borders Massachusetts to the south, Vermont to the west, Maine and the Gulf of Maine to the east, and the Canadian province of Quebec t ...

for several years but amid opposition by religious lobby groups it was banned in 2008 and a proposal to legalize it was rejected in 2013. Alkaline hydrolysis has been used for cadavers donated for research at the

University of Florida The University of Florida (Florida or UF) is a public university, public land-grant university, land-grant research university in Gainesville, Florida, United States. It is a senior member of the State University System of Florida and a preem ...

since the mid-1990s and at the

since 2005.

UCLA The University of California, Los Angeles (UCLA) is a public land-grant research university in Los Angeles, California, United States. Its academic roots were established in 1881 as a normal school then known as the southern branch of the C ...

uses the process to dispose of donor bodies.