During my internship and my master thesis writing in 2014, there was a visitor in the farm that recorded the anthroponic system me and my coordinator were working on. The system design can be viewed below, as well as a short video where I try to quickly explain how the system works:
For those interest in learning more about aquaponics before exploring anthroponics, I highly reccomend FAO’s resource on aquaponics. It is the most complete aquaponics document I have seen to that and offers tons of information on how to get started. It is available for free in the United Nations website as well as below:
Recently it has occurred to me that the definition of Anthroponics (alternative farming methods using recirculating water and a soilless medium, and with human waste as the source of nutrients) can be expanded.
What is human waste? Human waste has been typically defined as biowaste, including both urine and feces, among other fluids. Traditionally it encompasses all body fluids and residue (such as nails, skin, hairs, etc) which are released by the human body in the environment and are biogradable. When we think of human waste we usually think of Blackwater, or the end result of combining water with urine and feces that reaches our contemporary wastewater treatment plants.
We can take a step back and also consider greywater as a type of human waste. Greywater can be defined as the water resulting after human use in activities such as washing (in sinks and dishwashers), showers, kitchen sinks and baths. This greywater usually contains a considerable less amount of human biowaste, but it will likely contain detergents and soap. The platform Greywateraction.org mentions using greywater for growing edible crops though keeping in mind that it is “essential to put nothing toxic down the drain–no bleach, no dye, no bath salts, no cleanser, no shampoo with unpronounceable ingredients, and no products containing boron, which is toxic to plants. It is crucial to use all-natural, biodegradable soaps whose ingredients do not harm plants. Most powdered detergent, and some liquid detergent, is sodium based, but sodium can keep seeds from sprouting and destroy the structure of clay soils. Chose salt-free liquid soaps. While you’re at it, watch out for your own health: “natural” body products often contain substances toxic to humans, including parabens, stearalkonium chloride, phenoxyethanol, polyethelene glycol (PEG), and synthetic fragrances.” (Source). This platform also provides a list of greywater friendly cleaning products.
It seems unlikely that a greywater system could work effectively in feeding a recirculating system without using soil, as many of the nutrients from human biowaste exist in lesser concentrations, and there are few widespread cleaning products that would not pose any risk to the crops and to human health. However, as environmental awareness increases and companies produce products that are biogradable and perhaps even benefitial when released into the environment, it is not surprisingly that greywater may in the near future acquire properties that make it usable for hydroponic use.
We could also take an even further step back in our definition of Anthroponics to include all human waste streams, particularly industrial wastewater. However, most of the current human waste streams are unfit even for release in the environment, let alone for use in agriculture, given that manufacturing processes create waste products not conducive to life. It is not unlikely to imagine a future where biofabrication methods (see relevant TED Talk) have transformed the manufacturing landscape, particularly in regards to leather and meat production, thus opening the door to Anthroponic applications. But for now it seems extremely hard to implement within current business practices.
It seems therefore apparent that embracing a wider definition of Anthroponics may be needed in the future, but the current definition and the current nutrient sources for Anthroponics (human biowaste) will provide enough challenges and opportunities for designers and engineers for the near future.
As we explore the potential to use human waste for growing food or crops, it is essential to not overlook or underestimate the potential health concerns of such an endeavor.
Let us start with u-anthroponics:
The current proposed methodology for using human urine in a sanitary way for an aquaponics/anthroponics application was documented in the master thesis “Aquaponics and its potential aquaculture wastewater treatment and human urine treatment“. There, the methodology used was based on the methodology used by Pradhan et al, in their 2007 research paper “Use of Human Urine Fertilizer in Cultivation of Cabbage (Brassica oleracea)––Impacts on Chemical, Microbial, and Flavor Quality” (Alternative link).
In both cases, the urine is separated at source from a healthy individual, under no type of medication and without any current disease. While this restriction prevents any large-scale application, it ensures a first layer of protection in terms of potential problems. After the urine is collected, it is kept in a sealed container where the process of urea volatilization will occur. That chemical reaction is described in p.12 of the master thesis and also in the wikipedia page about Ammonia volatilization from urea. The urine is generally stored until its pH reaches a value of 9, which according to Pradhan et al achieves a reduction of the bacterial population and therefore its sterelization. Further research such as conducted by Hilt et al has shown that fresh urine is not sterile, so a sterelization step such as the one described above is necessary to ensure further sanitation.
However, reaching a pH of at least 9 is a process that can take several weeks up to a month depending on several conditions. There is little information on how to optimize this process, and as such its an essential area that warrants further research for future anthroponic applications.
Moving on to f-anthroponics:
Since there is no record of a feces based aquaponics system ever being constructed, there is little information on how safe this practice would be or if at all possible. However, there exists some base research done which allows us to infer how such a practice could be created and be sanitary, thus protecting its users.
As described in the Types of Anthroponics Systems, the feces would be collected into a recipient where black soldier fly larvae would consume the feces. This process is described by Banks et al 2014 research paper “Growth rates of black soldier fly larvae fed on fresh human faeces and their implication for improving sanitation” (Alternative Link), where it was reported that feeding black soldier fly larvae human feces resulted in significantly larger growth. On the other hand, feeding black soldier fly larvae is a well-known type of fish feed practice in the aquaponics community, having been documented by the master thesis “Integrating Biosystems to foster Sustainable Aquaculture: Using Black Soldier Fly Larvae as Feed in Aquaponic Systems” (Alternative Link).
In order to enable this type of feces-based anthroponics system, some sort of sanitary action must be taken between the harvesting of the black soldier fly larvae and its use for feeding the fish. I proposed a solution in the anthroponics subreddit, which explained:
- Only use feces from a healthy individual, under no type of medication or without an illness, and without any blood on the feces;
- freeze the papua before feeding them to the fish;
- most importantly, keep the handling of the feces/larvae and touching the plants separate, and always wash your harvest thoroughly just in case.
So, basically, the way to ensure the process is sanitary, according to my current understanding of some microbiological processes, is to follow a simple precautionary process to u-anthroponics, and on top of that to wash/clean the harvested black soldier fly larvae, to freeze them and to always keep the handling of the feces/larvae and the growing plants separate.
However, unlike u-anthroponics, f-anthroponics requires a much stricter waste handling since the feces arent sterilized, and overal has more problems that need to be overcome. In theory, f-anthroponics systems (as the one described in this blog) can be sanitary, but only a real world prototype with adequate testing material will be able to compare the final product with, for example, an equivalent product using cow manure as fertilizer.
I have recently finished my master thesis on the topic of aquaponics and its potential aquaculture wastewater treatment and human urine treatment (aka “peeponics”). While I wasn’t able to mention the term anthroponics (as it wasn’t used widely enough), this thesis can be considered one if not the first academic document on the topic of anthroponics (more specifically, u-anthroponics). The thesis is in english and can be viewed below:
Alternatively, it was uploaded to mediafire and shared with the r/aquaponics and r/anthroponics community. The mediafire file can be viewed here.