Hydro Cremation vs. Traditional Cremation

What is hydro cremation?

Hydro cremation, also known as alkaline hydrolysis or water cremation, differs from the commonly known process of cremation. While the end products are similar to each other, the difference is in the process. One uses fire, the other uses water.

 Resomation Ltd. image of hydro cremation vessel

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.

The term cremation has been misleadingly applied to alkaline hydrolysis as a way to introduce the general concept to the consumer marketplace. The association also deflects attention from the potential ‘ick factor’ presented by the process.

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.

What is the process of hydro cremation?

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.

According to Village Memorial BlogSpot, the process involves:

  • The body is placed inside a specialized steel vessel.
  • 80 or so gallons of an alkaline solution of water and potassium hydroxide are added.
  • The vessel is then heated up to about 300 degrees.
  • After two to three hours, soft tissues are dissolved into liquid.
  • The remaining bone fragments are then ground up into a fine white ash, and returned to the family.

In a more detailed, scientific explanation, the website Funeral Consumers Alliance of Minnesota (“FCA”) states:

The dead human body is placed in a pressurized stainless steel chamber where water (95%) and alkali (5%) are added and the temperature raised to 350 degrees. Water, alkali, heat and pressure circulate over the body to cause a reaction that hastens the decomposition of soft tissues. (Translation: it completely dissolves everything - flesh, organs - except bone fragments.) The resulting sterile solution is drained from the pressurized chamber, leaving behind soft bone fragments. The sterile solution is recycled through the waste water treatment system.

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.

What is left after hydro cremation?

Soft tissue has been liquefied as described above. The ashes remaining at the end of the process are similar to those after a traditional cremation, but are larger in volume and more finely textured. Where traditional cremation produces a coarse grayish material, hydro cremation leaves a pure white powder.

The FCA describes the end product as: “bone ash, but the ash is whiter than flame cremation, and of a finer consistency, almost like flour. Green Cremation preserves 20+% more bone fragments than flame cremation. In choosing Green Cremation, you'll need to make sure the container (urn or otherwise) you use is large enough to hold the additional amount of ash.”

Choosing a cremation urn after hydro cremation

It is essential to note the importance of choosing a larger cremation urn to hold the ashes after hydro cremation, such as the Athena Pewter Cremation Urn, versus traditional cremation.

When the process is complete, it produces up to 20 percent more bone ash than traditional cremation. The How Stuff Works Science website states that an average human body can produce from three to nine pounds of ash, depending on the bone structure and weight of that person. An accepted method of estimating volume is to figure on approximately one cubic inch of ash per pound of body weight for a traditional cremation. For hydro cremation factor up by about 20 percent.

What are the benefits of hydro cremation vs. traditional cremation?

Proponents of hydro cremation offer many reasons for choosing this method of disposition. Most significantly, it is an eco-friendly alternative to being embalmed and buried. The following benefits are listed by Village Memorial:

  • No harmful mercury emissions.
  • Far less energy used than in traditional cremation.
  • No burning of caskets.
  • Cleaner - No emitting of toxins or dioxins into the atmosphere.
  • Less carbon dioxide production than incineration cremation.
  • Bone ash remains are 100% unique to the individual
  • Byproducts enrich soil chemistry.
  • The bone ash (Calcium Phosphate) is 100% sterile, completely neutralized, disease and pathogen free.

The FCA refers to hydro cremation as “green cremations” and lists these benefits on their website:

  • 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.

How do I find a service provider?

Misunderstanding about how alkaline hydrolysis cremation works is prevalent. Therefore, currently the practice is not widely available. Legal precedents and popular acceptance of new customs surrounding death are often very slow to change.

According to the science, technology and design blog Gizmodo,“Alkaline hydrolysis is currently legal in only 8 U.S. states. Despite being one of the cheapest and most environmentally-friendly forms of dealing with a [body], it is not an option for most of us. … The process is currently legal in Colorado, Florida, Illinois, Kansas, Maine, Maryland, Minnesota, and Oregon.”

The FCA’s webpage champions Minnesota as the first (made legal in 2003) and one of only a few states where alkaline hydrolysis is available to the public. The Mayo Clinic in Rochester refers to hydro cremation as bio cremation. The Bradshaw Funeral and Cremation Services in Stillwater and the Mayo Clinic in Rochester are currently the only options in Minnesota for bio cremation.

If you live in one of the other seven states (listed above) where hydro cremation is available, you can find out about locations near you by performing a quick search on the Internet for service providers in your state. Alkaline hydrolysis cremation is slowly becoming more widely accepted and laws are changing to accommodate this practice, so there is likely to be a lot of change occurring in the near future.

How much does it cost?

Prices will vary significantly from provider to provider, so be sure to inquire locally if you intend to go this route. The Funeral Consumers Alliance of Minnesota estimates that:

Basic Green Cremation (no on-site ceremony) is $2,395, three times the lowest Direct Cremation price in the Twin Cities Metro area, but less expensive than some funeral homes charge. (One small-town funeral home in southern Minnesota charges $4,320 for Direct Cremation, one of the highest prices in the state.) Some observers predict the price will come down as other funeral homes offer Alkaline Hydrolysis. However, the high cost of the Resomator, the stainless steel pressurized chamber used for Alkaline Hydrolysis, means it's unlikely many funeral homes will be adding this option to their General Price Lists.

As stated above, the price of hydro cremation should come down as the technology is more widely distributed and gains broader acceptance from the general population. Market forces will inevitably drive costs down as hydro cremation becomes more widely available, promoting greater competition between providers. But for now, it remains priced significantly higher than traditional cremation, but lower than the costs incurred from a traditional burial.

Is it regulated?

According to the Cremation Association of North America and the National Funeral Directors Association, at this point in time, alkaline hydrolysis is regulated on a state level. In the future, with wider acceptance, this may change. Currently with only eight states in the union using hydro cremation, there hasn’t been a call for federal regulation.

Cremation urns suitable for cremation ashes after hydro cremation

The question of whether the remains received after the process belonged to your loved one is always present. But because there is only one body ‘cremated’ at a time during hydro cremation, this doubt is eliminated.
Many affordable, tastefully designed and interest-specific cremation urns are available. Consider a cremation urn for display, a scattering urn or a biodegradable urn to be buried or planted with a tree. Your thoughtful choice will honor your loved one.
Continue shopping
Your Order

You have no items in your cart