Have you ever considered the environmental impact of end-of-life body disposal?
The carbon and environmental impacts can be huge when aggregated across the millions of animals that require end-of-life body disposal every year. Cremation results in combustion emissions and burial can lead to leaching of various chemicals including chemotherapeutics, antibiotics, euthanasia barbiturates, and other into the environment.
Aquamation is an eco-friendly and safe end-of-life body disposal alternative that uses a combination of water, 5% alkalinity (KOH, NaOH or more commonly a combination), moderate temperature, and pressure. The process used is called alkaline hydrolysis, which was originally developed and patented to make a by-product fertilizer from animal carcasses in 1888 by a farmer named Amos Herbert Hobson.1
More than a century later, in the early 1990s, two researchers at the Albany Medical college, Drs Kaye and Weber developed a tissue digester using the alkaline hydrolysis process with temperature and pressure, to assist with disposal of research animal tissue material. In 1994 they formed the company WR2 and received a patent. In 2006 the company closed and Joseph Wilson the president and CEO of WR2, formed Bio-Response Solutions using a low temperature method (BioLiquidator) with the goal to produce a mobile tissue digester for emergency response and disease control. In 2008 the first BioLiquidator was installed at a pet crematory in Ohio. At the same time Sandy Sullivan the WR2 European subsidiary lead, formed Resomation Ltd in the UK using a higher temperature more rapid method, specifically for human disposition, where there was a recognized niche due to the extreme costs of mercury scrubbers for crematories.2
These and similar alkaline hydrolysis systems are now used throughout the world for human, pet, and medical research tissue material disposal where they are known by other various terms including water cremation, flameless cremation, and biocremation. Note that Resomation actually refers to a proprietary process that uses higher temperature, pressure and shorter cycle times. Both Aquamation and Resomation are trademarked. One of the most prominent figures to have requested this form of disposal is Archbishop Desmon Tutu, a champion of the environment during his life, and catapulted Aquamation onto the international stage in late 2021.3 Pet Aquamation services are available increasingly around the world including the US, Canada, UK, Australia, New Zealand, South Africa, Mexico, and some countries in Europe and Asia.
Alkaline hydrolysis is a reductive process and accelerates what takes place during normal body decomposition. Proteins, RNA and DNA are broken down into small peptides or amino acids, sugars are formed, fats are reduced to biodegradable soap, any drugs or chemicals are similarly broken down and dissolved in the effluent called hydrolysate. No infectious organisms or harmful chemicals remain. The bone and teeth mineral, calcium phosphate, is all that remains.2
Although the temperature, time, size, and exact combination of alkaline used in the process can be varied, the main provider, Bio-Response Solutions, uses cycle times of 12-20 hrs, at 200°F, at atmospheric pressure for pet systems. The size of the steel container varies from a single small animal system to one that can accommodate large animals such a horse. Most available systems also have cage compartments to allow individual vs communal disposal. The amount of water used per pet is the equivalent of 1-3 pet baths. The resulting sterile, non-toxic effluent is treated and returned to the local municipal wastewater treatment facility.4The residual mineralized bony remains of calcium phosphate are crushed to a powder and returned to the owner if cremains are requested.
According to an extensive life cycle analysis (LCA) done in the Netherlands in 2011, Resomation is the least carbon and environmentally impactful body disposal method when compared to three others: burial, cremation, and cryomation. Following a quantitative analysis, Resomation had a “shadow price” or true environmental costing/unit of impact of 85 times less than burial and 33 times less than cremation, as shown in Figure 1 below. Areas of impact considered in this comprehensive study included abiotic depletion, acidification, eutrophication, global warming potential, ozone layer depletion, photochemical oxidation, land competition, human toxicity, freshwater aquatic toxicity and terrestrial toxicity. 5
Figure 1: Environmental Impact of Funeral Techniques from Keijzer, E.E., 2011. Environmental impact of different funeral technologies, TNO report5
The impact of pet animal cremation: shelter animal example
The total number of pet dog and cats euthanized every year in the North America is difficult to estimate. The number of shelter dog and cats euthanized per the ASPCA in 2024 was 607,000.6 If all these animals were cremated, this would result in approximately 19,000 metric tons of CO2e emitted, which is the equivalent of driving 47.5 million miles.7
Calculation: 273,000 cats @ 4kg each, 334,000 dogs @ 15kg each. Cremation = 245kg CO2e/80kg person8. Total CO2e of shelter animals euthanized in 2024 per ASPCA= 18687 metric tons of carbon.
Choosing to offer your clients a less impactful and increasingly available alternative end-of-life disposal is an important step to providing more sustainable veterinary care. In addition, many clients are now evermore aware of the impacts of embalming, standard burial, and cremation and are themselves choosing greener alternatives for their human relatives.
References:
- https://www.cremationassociation.org/alkalinehydrolysis.html
- https://www.goodfuneralguide.co.uk/wp-content/uploads/2013/09/History-of-Alkaline-Hydrolysis.pdf
- https://www.bbc.com/news/world-africa-59842728
- https://aquamationinfo.com/petsystems/
- Keijzer, E.E., 2011. Environmental impact of different funeral technologies, TNO report, TNO-060-UT-2011-001432. Available from: <https://www.funeralnatural.net/sites/default/files/articulo/archivo/environmental_impact_of_different_funeral_technologies.pdf/>. Accessed on 23 May, 2022.
- https://www.aspca.org/helping-shelters-people-pets/us-animal-shelter-statistics
- https://www.epa.gov/energy/greenhouse-gas-equivalencies-calculator
- https://edu.rsc.org/feature/how-science-can-make-burial-cremation-and-memorial-greener/4018384.article
