There was quite an interesting discussion lately on the ecosanres discussion forum which is run by SEI. For me, I find it a real pity that that particular discussion forum is closed and only e-mail based, so I have asked Ralf Otterpohl if I can copy his recent postings across to here so that they are out in the open and can be re-found more easily. Ralf is a well-known professor in Germany (Technical University Hamburg-Harburg) who has published on ecosan topics since several decades and whose current main interest is in Terra Preta Sanitation.
(I didn't copy the other responses, not because they are not good as well but because I haven't asked the particular people yet for their permissions)

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On Apr 3, 2012, at 8:32 PM, Ralf Otterpohl <ro@...> wrote:

Dear Carl,
Dear All,

I agree in long term separation of above 10 years until no crop restrictions apply. However, in many cases the excreta compost can be highly beneficial to help reforestation, to create beneficial trees that avoid land erosion and provide fodder, later even food. Moringa Oliveira trees are amazing in multiple benefit, the leaves are great fodder (up to 40% for goats fodder see reader in www.anamed.net), seeds useable for greywater precipitation or drinking water purification. At the same time roots build humus in the surrounding soil improving yields, too. After 10 years in excreta compost leafs can also be highly nurishing food, the taste after being cooked is like mangold/swiss chard and spinach. Unfortuntely only in the warm climates. Such concepts with Moringa (not yet the excreta compost I guess) are used in Ethiopia in the South West in a really dry region with great success. With this goats could be kept in fences thus allowing re-growth of natural and man-made vegetation.

Further great trees are Neem (besides 40 great benefits to man excellent goat fodder see ANAMED) and we should look more for the Annatto Tree (Lipstick-Tree), it has the potential to provide nutrition for humans yielding as much as intensive wheat fields on the same area but restoring it at the same time and allowing veggie production under them, too. Compost is very often urgently needed to get trees tall enough to survive the growth phase. The Composting Group in Arba Minch (involved in EU CLARA project of Gunter Langergraber) does apply this 'trick' to sell compost, you buy a bag with a small tree and buy 3 bags of compost with it to have it growing.

For sanitisation: Lactic Acid Fermentation is highly efficient even before the composting in the toilet, good thermo-phase later followed by vermi-composting is pretty safe - plus 10 years of crop restrictions for hygiene and wash out of micro pollutants. We will get high amounts of compost when we also compost urine with woody waste (200 kg/person /year allow evaporation in between) and even better with addition of some charcoal. See www.tuhh.de/aww for many downloads of over a 100 person years of intense practical ecosan research including vermi-composting.

Kind regards

Ralf

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On Apr 10, 2012, at 11:26 AM, Ralf Otterpohl wrote:

Dear Carl,

The great thing is that we have so many options at hand that all have their upsides and downsides. Your system has some clear advantages, no doubt.

Improving soil is the thing to do to assure the base for water and food security, therefore we work on systems that produce maximum humus also from urine. Not from the desk but with lots of practical applications. The diffence may be that we work on developing professional systems that can serve millions at low costs. Densely populated areas are often not all that suitable for huge chambers. The collection effort for excreta and urine in the peri-urban and urban is that same as urine dominates volume. Composting in our approach is ideally done where the humus is used (non-food for the first ten years), where the soil is, as transporing twice does not make a lot of sense.

Kind regards

Ralf

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Re: Compost for Trees Re: EcoSanRes: Composting Reduces Growers' Concerns About Pathogens!

Dear Richard,
Dear All,

Everybody is free to use more or less well sanitized excreta for his or her own food supply. The risk is low in this case, as an emitting person will just infect a person taht is ill already. For professionals in sanitation we cannot do so because we do have a certain risk of spreading nasty diseases. This is unneccessary because we can grow our food with the kitchen waste and utilize excreata compost non-food eg for planting trees.

One pathway that is not considered even by hygienists (obviously there are many people also overdoing this issue..) is the uptake of bacteria through roots of vegetables. This pathway is called endocytosis in plants and very well proven by respected universities. E.g. E-Coli has been found to move inside the plant alive until it will be digested at some time. Now I will not put anybody at risk by implementing systems where there is a pathway shorter than 10 years from toilet to vegetables.

In Germany we have had severe incidents with EHEC - where there are species of E-Coli that are deadly. The victims in Germany last year ate sprouts from seeds that had been watered with wastewater. Richard, when your secretary, who likes your spinach from the toilet compost falls ill, you will be responible at least morally. In the school of my children we just had an EHEC warning, this is not so rare as we may think. And there is a lot of pathogens around.

If we as Ecosan community want to be taken seriously as professionals in sanitation we must get away from unnecessary risks. Almost everybody around the world does hate to eat veggies from toilet compost (almost always at far too low temperatures) and I cannot follow the obsession some of us have for promoting exactly this. Excreta compost is so little that we can easily keep it separate and bring to the ecological loop in a longer time span. Many people are repelled by the nice drawings from toilet to mouth, few will tell us.

I do respect your motivation and your good work, but flexibility and adaptation is something great. Let us move to the safe side where the health and lifes of others are can be affected.

Kind regards

Ralf

Ralf Otterpohl
Univ. Prof. Dr.-Ing.
Director
Institute of Wastewater Management and Water Protection
*** focus on Resources Management Sanitation / Ecosan
TUHH Hamburg University of Technology, Germany
www.tuhh.de/aww

Dear all,

Il Walonia (southern region of Belgium), according to the law, sewage sludge can't be used on eadible plants (fruits and vegetable crops, usualy eaten raw) if spread less than 10 month before harvesting. (The main issue adressed by the legislation is related to the heavy metals).

I've never heard any problem related to pathogens because of this practice. In France, where sewage sludge is widely used, there seems not to be pathogenic problems related neither. Lime is ofter used to kill (inactivate?) pathogens and enhance agronomical value of the products.

Is there any reason for having stronger laws with "humanure" than from sewage sludge?

Where does the "10 years rules" come from?

Thanks in advance for your opinion,

Best regards,

Geoffroy Germeau

Dear Geoffroy,
dear Ralf,
dear all,
in Germany the application of sewage sludge is prohibited on horticultural grounds, fruit orchards and pasture.
The regulations for UK following GAP (good agricultural practice):
www.environment-agency.gov.uk/netregs/bu...riculture/61893.aspx
I fully support Ralfs suggestion. Expenses and risks are relatively high for few manmade shit. Wood or perennial plantations are to be chosen.
EHEC bacteria is initially spreaded by cow-manure from highenergy protein feeded cattle. The more of that feed, the more bacteria. In Germany usually they don´t applicate cow manure as fertilizer in horticulture - too dangerous. But the postgraduate agricultural engineer who prepaired my hobby garden plot (Bioland Ecological certificated) applicated a lot of cow dung at the end of january. Allowed but problematic.
Important to take care and to remember the both aspects of food security.
TUHH published a lot of important stuff. Thank you for publishing under Creative Commons. Last December I discussed EHEC (COW-DUNG vermicomposted) in Alamar/Havana/Cuba referring to the (HUMAN-DUNG) dissertation of Buzie-Fru "Development of a continuous single chamber vermicomposting toilet with urine diversion for on-site application" doku.b.tu-harburg.de/volltexte/2011/1095/
Gerhard Pelzer
Consultant Social Marketing

Interesting discussion - SuSan Design is testing sanitized human excreta in maize production in Uganda and we hope to bring about a safe/practical way to add the nutritional value of human excreta to farm production. Our results shold be avaialble in August.

Dear all, Dear Ralph,

I am in France manufacturing some dry toilets and the question of the use of the excreta is a permanent question from users.
As Geoffroy says, in France sewage sludge is spread with or without composting before spreading.
I say to users that we think that there is no risk in spreading vermi-composting coming from toilets but we invit them using the compost on trees or non eadible plants. Each time we do analysis, we have compost that can be consider as compost for each type of plant in the frensh law. This i confused and not logical
Can we consider that there is a different risk in using compost from european people than using compost coming from region where there are different disease or bacteria ?
Or is there no différence between countries in the world ?
Do you think that the law and rules in european countries are not linked to recent resarch ?
What about European rules in that sector ?
What is real and what is supposition ?

Thank you for your answers

Emmanuel
Ecodomeo

Dear Emmanuel,
dear all,
infections by intestinal parasites will be the biggest problem by number of cases. "Enterobius" attacking worldwide and only transmitted between humans is not very problematic for health. Parasistism caused by other types of worms in combination with diarrhoea is more a problem of tropical and subtropical regions and main reason for poor developement of children. To kill worm helmeths, compost temperature should reach 70 degrees Celsius.

Most of the harmfull bacteria multiplies in bodies of humans and other warm-blooded animals. Viruses, E. coli, Salmonellae and Shigellae may survive some month in soils. Perfect hygienisation by earthworms will reduce bacteria significant and in most cases no bacterial infection will happen after consumption of food fertilized with that material.

Midrange temperatures, midrange moisture, optimal conditions in your garden for bacteria to live long. Normaly there must be lot of one type of bacteria entering your body to start the specific infection. Mentioned EHEC E.Coli needs only a few bacteria to start a a potentially life threatening disease. They may live for a long time in plants.

Risk is a statistical issue. Risk assessment is always culture-dependent. Water in USA must be bacteria free. In Germany we allow more bacteria and dont want as much chlorine in water as in USA. We don´t fear food fertilized organic. Your customers might reinfect themselves with intestinal worms, Maybe there is a inner-family ping-pong infection and some neighbors become infected too. It´s not complete riskless, but will not be responsible for epidemic situations. To collect shit in cities for the production of fertilizers beeing connected with all parts of the world by plains, too dangerous in my opinion.

Is the application of sludge good or bad and what is the difference? The sludge usually is not used on horticultural grounds, the same for compost from seperated collection. If used on eg. sugar-beets, wheat, potatoes the problems are more on the heavy metal content than concerning bacteria, for the bacteria will become killed before eaten. If the wheat/flour is not used crude (is this a real problem, or only a theoretical), not a problem using your compost.

Gerhard Pelzer

Dear all,

First of all, thanks Elizabeth for broadening the discussion by transferring it to this forum too.

I think a lot of Ralf Otterpohls (and other comments) out of the ecosanres posts are very valuable, it would especially be interesting to hear more about the endocytosis path way (Can Martina Winker help us here?). For me they also echo a discussion we had here end of last year, this was the "reuse of faecal matter, is it worth it?" discussion thread, that ran into 4 pages and contains a lot of very useful info.

Elizabeth, would it be possible to have one of your colleagues go through that tread again and compile the key information and then add it to this discussion?

As I recall, the threat mentioned above also came to the conclusion that we need more stringent rules on how to post-process and/or use faecal waste. For the time being, I would agree with most comments made here to apply faecal waste only to non-food crops. Considering the small volumes this should not be a problem and could encourage tree planting.

I have probably said this before, but I think further research into how to safely use faecal waste and also how to handle waste streams from DEWATS systems, should be a priority for Ecosan research.

Kind regards

Marijn

Dear Geoffrey,
Dear All,

As you know most people will reject eating food from excreta compost. If food for others is produced, this must be respected. Few people would reject if this is 10 years old compost.

In addition we have lots of nasty pharmaceutcal residues and hormones from the pill. Over 10 years even those many absolutely non-biodegradeable ones will have been washed out.

Another aspect: all the composting is stil not relly really save for all pathogens at all times of operation. 10 years is short and jsut another saftey measure. Plenty of non-food-applications.

Another point: generally accepted scintific knowledge is just a fraction of what is going on in the universe, actually very crude and somewhat mediaeval. Quantum physics do apply to life. Entanglement means that there can be links of substances that have been attached somewhere. There is plenty of proof that also frequencies of substances can be imprinted on water. As crazy as this may sound, I personally do not want such links to other people. Such thinking is familiar to millions of people and there are traces of this in old cultural knowledge, too. E.g. this is part of the thinking behind Biodynamic Farming (they would say 7 years, I am more in the metric system). I would have called the authors crazy if i had seen this statement 30 years back : )

For all those resons: plant staff on your composted excreta if you eat this yourself or people who know and accept. Do not misuse trust of people who would not like it or even hate it. This is one of the resons we work on composting all excreta including urine with sufficient woody waste and some charcoal from woodgas stoves.

Kind regards

Ralf

Dear Marijn!

Example reference to Endocytosis of plants (it is an amazing topic! uptake of living bacteria though roots). If the community is wide awake we must change our practice. Legislation does not consider this pathway:

Turning the Table: Plants Consume Microbes as a Source of Nutrients
Chanyarat Paungfoo-Lonhienne1*, Doris Rentsch2, Silke Robatzek3, Richard I. Webb4, Evgeny Sagulenko5, Torgny Näsholm6, Susanne Schmidt1#, Thierry G. A. Lonhienne1#
1 School of Biological Sciences, The University of Queensland, Brisbane, Queensland, Australia, 2 Institute of Plant Sciences, University of Bern, Bern, Switzerland, 3 The Sainsbury Laboratory, Norwich Research Park, Norwich, United Kingdom, 4 Centre for Microscopy and Microanalysis, The University of Queensland, Brisbane, Queensland, Australia, 5 School of Biochemistry and Molecular Biosciences, The University of Queensland, Brisbane, Queensland, Australia, 6 Department of Forest Ecology and Management, Swedish University of Agricultural Sciences, Umeå, Sweden

Citation: Paungfoo-Lonhienne C, Rentsch D, Robatzek S, Webb RI, Sagulenko E, et al. (2010) Turning the Table: Plants Consume Microbes as a Source of Nutrients. PLoS ONE 5(7): e11915. doi:10.1371/journal.pone.0011915
Received: June 7, 2010; Accepted: July 7, 2010; Published: July 30, 2010

Kind regards

Ralf

Dear Ralph,

Thanks for the link to the article, I have not had time to really read it but it looks very interesting.

To the whole comunity,

A further question that hopefully someone can answer.

In many texts on Twinpit / Sulabh toilets, there is a claim that after 2 or 3 years of storage of the excreta in the pit that is not in use the remaining compost is pathogen free, apart from worm helminths. Does anyone have a link to a (recent) paper that either supports or refutes this?

Kind regards

Marijn

Dear Ralf and all,

I am a physician (Dr. med.) by qualification and half of my 58 years of life I have been living in Tamil Nadu, India. I had hepatitis A, amoebiasis, giardiasis (many times), ascariasis (roundworm), various diarrhoeas etc. yet I think that most of the offical standards (international, national) are overdone i.e. based rather on fear and on the concept of surgical hygiene (where hygiene = absence of all microorganisms) than on an understanding of soil microbiology, microbiological metabolism and ecology of soils etc. (I do not claim that I understand.)
The damage (in regard to the environment and to public hygiene) that is being done by mankind to itself is not due to low standards, but due to ignorance and carelessness about them, also carelessness at criminal levels.
I am also promoting biodynamic (BD) farming and respect the particular qualities and strengths of this type of farming, but I cannot accept the in-principle banning of human waste recycling into soils from the scenario of (certified) organic farming or of BD farming in particular. Organic farming argues with the risk of pathogens and pharmaceutical residues, but not dealing with the "shit" does not end it to exist. BD farming (Steiner) argues with the lack of life force (prana), and, as Ralf mentions, other fringe sciences argue with the information imprinted into water and possibly other biological saps and substances. (If the science of info imprints is on the right track, imprints can also be undone, corrected, "reprinted".)
All this is to simply state that we seem to need some more serious research in this field to arrive at a healthy middle way between "risk" elimination at ppt levels and over-confidently heroic messing around with our own excreta. I am not afraid, we seem to be on the right track.
Rgds, Lucas

Dear all,
very interesting discussion. I find the statement of Lucas very logical and convincing. There needs to be a sound and healthy middle way for use of excreta as it is a precious resource and at the same time poses health risks. It would certainly be the easiest way to restrict the use of excreta as proposed to only non-edible plants or at most fruit trees. Since the human factor will always lead to the mentioned carelessness of standards to a certain extent there needs to be clear and simple rules to follow. Looking at WHO rules it is mind-boggling and too complex to understand. In this sense the simple message of BD-farming (Steiner) not to use human excreta in agriculture is easy to remember and easy to follow. On the other hand such a rule might be too strict and steal the potential benefits for farmers. So where is the middle way - could SuSanA community try to come up with a recommondation of simple and most beneficial rules for use of excreta in terms of minimising health risk and taping the benefit of reuse?

As this fits to this topic so well, let me share with you the video of Soil on the agricultural activities with human excreta. The most critical part (around 6:45) is when people and even children apply the composted excreta with their bare hands on the soil. They use it for all kinds of vegetables etc...how would you guys appraise this practice?



Cheers
Christian

Dear Christian,

Thanks for posting this.
I was asked by SOIL to closely read their publication: "The soil guide to ecological sanitation", now also in the Susana library, to come up with suggestions for further editions.

The compost in this video has been treated at their central composting plant. The method they have created for composting faeces at a reasonably big scale, to me seems the most advanced I have ever read about. In their publication they claim the following (which I am willing to believe):

1. They build their piles in such a way that the edges, which may not get warm enough for sterilization, do not contain faeces.

2. They monitor the temperatures of the piles and measure daily in a number of locations, to guarantee that all the material stays over 50 degrees Celcius, for 2 months. This system is based on literature: (Cairncross et al., 1993) which states that faecal matter will be safe after composting at 50 deg C, after 1 week.

To the best of my knowledge they have not yet been able to test the compost in a microbial lab, I have suggested them to do this at the earliest possible time, to verify their sterilization process. Maybe one of the SOIL people is a member here and can tell us what the word is on that?

Anyway, in short:

I think, based on the description of the system that the risks associated with their composting system are very small, especially compared to household scale treatment systems.

The safety of their compost should however be validated by lab analyses (preferably as an ongoing effort for each batch). If that has not happened yet.

Further, many of the issues raised earlier in this thread are of a cultural nature, apparently the people SOIL works with have overcome those.

Last, I would also suggest that compost from faeces should only be used on (fruit)trees, unless a secondary treatment, that is verified by lab analyses, has been used.

rgds

Marijn

Interesting discussion... just a quick remark from my side (I think that has not been mentioned yet; Edit: Gerhard Pelzer already mentioned it to some extend and it was also mentioned in the first post; but well for the sake off stressing this fact I will leave this post here):

Coming from a water-supply background: there has been an discussion in how far the recontamination of drinking water at the household level is a problem or not. And while you can usually measure an increase in coliform contamination at this level one has to keep in mind that illnesses do not spread this way, in contrast to a contamination at the water source or in a distribution network. Additionally one can expect that the inhabitants already have an acquired immune response to those pathogens that are present in the direct surroundings of their HH (note that this does NOT really help the children below 5 those immune system is still mostly untrained).

To some extent this line of reasoning can be applied to reuse of faecal material as fertilizer too; e.g. as long as the faecal material used is only "their own", and the food produced is only used for their own consumption (and not sold on the market for example), you will not spread illnesses and the negative health-effect will be relatively low.

Obviously this is not really the optimal solution, but I think this is something to keep in mind too.

Rural toilet systems where the owners want to reuse their excreta should preferably be UD in order to reuse the big amount ot nutrients with very low hyginic risc. We do prefer composting of urine with woody waste to make good soil conditioner as we follow organic agriculture. Direct application of mainly mineral fertilizer is no healthy way of plant nutrition. Kitchen waste and yard clippings would be added here.

Faecal matter will hardly ever be composted in a safe way with above 70 °C on site so this should clearly be non-food for a long period of time. amounts are very small anyway. 'Their own pathogens' is not applicable as the wife may not wish to get sick through her husband or to contaminate visitors. There is a lot of nasty stuff that can survive in faecal matter.

Dear all,

I also have a reservation about the "only using for growing food consumed within the household" rules (also regarding urine). I practice this is pretty much impossible to enforce. Especially vegetables tend to ripen all around the same time, so for example people have too many cucumbers and barter them for some rice or corn. As Ralph indicates above, for faecal waste the risks are bigger then for urine, because there are many more pathogens in faeces including some more severe ones than in urine.

Ralph, regarding your comment on using urine as a mineral fertilizer.
I would always advocate using compost (non human waste based) together with urine. To promote the living soil concept. As I believe that is a more efficient process than co-composting the urine, in terms of: nutrients preserved, simplicity, labor and input requirements for farmers. So I agree that using only urine is as bad for soils as using only synthetic fertilizers, but I would think that a compost and urine strategy is as good as your co-composting technique. Any thoughts on that anyone?

rgds

Marijn

Dear Merijn,

The main thing is to convert mineral nitrogen like the ammonia in urine into organic forms ideally humic acids. Works well with combining woody waste - if dry they can absorb and evaporate excess of moisture. In addition this leads to much compost compared to teh frustration of the shrinking organic mass without woodbase.

In German: 'Holz macht Boden stolz' meaning 'wood makes soil proud' as an old saying among farmers.

Ralf

Dear Ralph,

Thanks again for your answer, these are all subjects that I work very closely on at the moment, so the information here is important for me. I do agree that humic substances are very important, mainly for long term soil health and fertility.

As I wrote earlier, at the moment my feeling is that a mix of compost (preferably including high lignen material such as corn stalks or wood) and direct urine application would create a healthy soil, with some additional short term fertilization from the ammonium and nitrate from the urine.
One of the reasons for this strategy in is that one needs very large amounts of compost to cover the nitrogen, potassium and phosphate needs of a crop. With a combined approach we can create a living soil, while using compost a bit more sparingly (which is important for the people I work with).

I would like, once more, to invite other subscribers to the forum to add their views to this topic.

One more technical question:
Does anyone have any data on how fast Nitrogen from compost (the organic part, so not the NH4 and NO3) becomes available to plants. In other words, if I make a calculation of the Nitrogen needs of a plant can I substitute the grams N from urea or other fertilizer for grams N from compost, or does the organic N in compost become available much slower?

Thank you

Marijn

Dear Ralf
Dear all,
I do not agree to the statement that ammonia in urine ideally should be transformed to organic nitrogen.

The grounds for my statement are:
1) The only way I know of transforming ammonia to organic nitrogen goes via bacteria. These use organics as their source of energy. But the bacteria do not only multiply, increasing the bacterial mass. They also have to respire. Thus, it is less than half of the energy of the organics fed to the bacteria that ends up in the bacterial mass, which is the mass containing the organic nitrogen. More than half will be lost in endogenic respiration. From a sustainability and greenhouse gas point of view, it would be far better to use the feed organics either for biogas production, if the feed organics are easily degraded like food waste, or to use it as biofuel for incineration, if it is woody waste. To use this energy just to build ammonia nitrogen into organic form is a waste which does not use the potential of the energy in the organics to decrease the greenhouse gas emissions.

2) In composts, often large proportions of the input nitrogen is lost, largely as ammonia, but also as nitrous oxide (N2O) and, in the best of worlds, as nitrogen gas. The nitrogen losses are especially large when composting substrates with lots of easily available nitrogen, and especially if the nitrogen is in the form of ammonia. E.g. in the paper "Nitrogen loss during composting of poultry litter" Venglovsky et al. (2011) report that 65% of the initial N was lost when poulty litter was composted and in "Nitrogen turnover and loss during storage of slurry and composting of solid manure under typical Vietnamese farming conditions" Tran et al. (2010)report that the losses were 45-55% when the pig slurry was composted with straw.

3) The nitrogen that ends up as organic nitrogen in composts has on average a very low efficiency in feeding the plants and thus in replacing mineral (chemical) nitrogen fertilizers. In a literature review by Odlare et al. (2000) they found that of the nitrogen in the compost, the literature indicates that on average about 0-15% is used by the crop the first year, another 5-10% the next year and in total over sevaral years about 20-30% of the organic nitrogen in the compost is utilized by the crops. One important reason for this percentage not being higher is that a lot of the organic nitrogen is mineralized when there is no crop on the soil to take it up. See the next bullet, no 4.

4) Organic nitrogen in the soil has a big drawback in that is is not directly available to the plants. It only becomes available after it has been mineralized and mineralization is not well syncronized with the need of the plants.
For mineralization, the soil moisture and temperature has to be suitable. In temperate climate like Sweden and Denmark, and I think also northern Germany our winter crops (winter wheat, winter barley, winter rape, etc.) need a very large part of their nitrogen very early in the year, when they start to grow in the spring. In mid Sweden, they need ample access to mineral nitrogen from about mid April. At this time the soil temperature is only just over freezing, which means that organic nitrogen is not being mineralized in the soil. By end of June, when the winter crops stops to take up nitrogen as they start to ripe, the soil temperature has increased to 15-20 degrees centigrades and thus then there is a lot of mineralization and this continues through the autumn. This in turn means that lots of nitrogen is mineralized at times when there are now crops that can take it up. Thus, a large part of the nitrogen that is mineralized in the late summer and autumn is lost in the winter and spring, causing eutrophication of e.g. the Baltic Sea.

5) Source separated urine has a unique and very valuable property in that it is readily plant available (see e.g. "Practical Guidance on the Use of Urine in Crop Production" at www.ecosanres.org/publications.htm). This means that it can be used to supply winter crops with the nitrogen when they need it and thus increase their health, competitiveness against weeds, and quantity and quality of their yeild. As it has such a high plant availability it can be supplied to the crop just before it is needed, thus minimizing the risk for losses and negative effects on the environement.

This is the reason why several of the large urine diversion projects in Sweden during the 90-ies were initialized by organic farmers. The farmers realized the unique quality of the source separated urine and they wanted it for improving the competitiveness of their crops against weeds and for better yields. Source separated human urine was, just as the manure from animals, allowed as fertilizers in organic farming in Sweden before we joined the EU, just as it still is by IFOAM, International Federation of Organic Agriculture Movements. It is a great pity that it is not allowed in organic farming by the EU.

I really think that the sustainability of a urine diversion system is decreased if the urine is used for composting instead of for fertilizing directly, because by composting only some 15% of the initial nitrogen will end up being used by the plant (50% left after composting and of this 30% is used by plants). The rest is lost to the environment causing large negative environmental effects (N2O, NO3, NH3).

If the urine instead is used directly as a fertilizer it can replace mineral fertilizers at a rate of 1:1, thus DECREASING the global warming caused by its production in the form of emissions of N2O and CO2.

I am open for any discussion of my conclusions, if this discussion is based on data from scientific publications.

With sincere wishes for increased sustainability,
Håkan

Dear Hakan,

Thank you for this contribution. Could you give a more complete reference for Odlare et al., 2000 ?

rgds

Marijn

Dear Hakan,
dear Ralf,
dear all,

important discussion. The last comments of Hakan and Ralf touch on questions about organic fertilizing in general. Far away from the topic: use excreta compost only for non-edible plants. Elisabeth should create a new topic. WG 3 - Renewable energies and climate change - should become invited to participate.

IFOAM regulation does not distinguish between human feces and urine. Today are human excrements prohibited for use on crops for human consumption. New IFOAM Standard will allow more in accordance to COROS assessment reference.

IFOAM Basic Standards (2005) still valid May 2012:
4.4.4 Manures containing human excrement (feces and urine) are prohibited for use on crops for human consumption.
Exceptions may be made where detailed sanitation requirements are established by the standard-setting organization to prevent the transmission of pests, parasites and infectious agents and to ensure that manures are not mixed with other household or industrial wastes that may contain prohibited substances.

New Standard under developement, actuall Draft 0.3 will be in discussion until June 2012. Draft version 0.4 will be the version submitted for a final approval vote. Regulation concerning human excrement since Draft Version 0.2:
4.4.5 Human excrement shall be handled in a way that reduces risk of pathogens and parasites and shall not be applied within six months of the harvest of annual crops for human consumption with edible portions in contact with the soil.

Draft History

IFOAM Standard Draft 0.1 (Version 2010)
4.4.5 Manures containing human excrement must not be applied on soil that will be used to grow crops for human consumption within the next six months.
Regional or other exception at certification body discretion
Exceptions may be made where detailed sanitation requirements prevent the transmission of pests, parasites and infectious agents and manures are not mixed with other household or industrial wastes that may contain prohibited substances.
4.4.6 Manures containing human excrement (feces and urine) are prohibited for use on crops for human consumption

IFOAM Standard Draft 0.3 (May 2012)
4.4.5 Human excrement shall be handled in a way that reduces risk of pathogens and parasites and shall not be applied within six months of the harvest of annual crops for human consumption with edible portions in contact with the soil.
4.4.6 Mineral fertilizers shall only be used in a program addressing long-term fertility needs together with other techniques such as organic matter additions, green manures, crop rotations and nitrogen fixation by plants. Their use shall be justified by appropriate soil and leaf analysis or diagnosed by an independent expert.

COROS, GOMA

COROS, Common Objectives and Requirements of Organic Standards (International reference to perform bi-lateral or multi-lateral equivalence assessments of organic standards)
Objective:
Sheet DATA ENTRY, 4.3.5 :
Organic soil fertility management does not use of human excrement on crops for human consumption without measures to protect humans from pathogens.

COROS Consultation Discussion:
Objective:
Organic soil fertility management does not use of human excrement on crops for human consumption without measures to protect humans from pathogens.
FiBL (Otto Schmid): nothing is said on soil tillage, which is a key criticism on organic farming: We might add: this includes the emphasis on soil conservation and minimum tillage practices.
GOMA-IFOAM answer (GOMA, Global Organic Market Access, a joint initiative of FAO, IFOAM and UNCTAD):
Rate of tillage is not commonly addressed in organic standards (which is why it is criticized) and therefore would seem out of place in a document that presents the common requirements. This document, an equivalence instrument, is not intended to lead standards in a new direction but to reflect the current status of organic standards.

More about Lisbon Treaty and how to change organic regulation in europe now: www.ifoam.org/about_ifoam/around_world/e...er_2012_EN_heavy.pdf

COROS, GOMA and humanure, one example:
GOMA (www.goma-organic.org), the Global Market Access project, is a joint initiative of FAO, IFOAM and UNCTAD.
GOMA organized a draft working group for co-operation on Organic Labelling and Trade for Asia and decided to develop Asia Regional Organic Standard (AROS). WG meeting: 26-27 September 2011, Seoul,
"Human Waste: It was noted by the standards developer that COROS and AROS currently have the same wording and also that two countries, Philippines and China, specifically allow it in their standards with restrictions. Discussion included adding more detailed language in the restrictions, the need to allow this substance due to the peaking and eventual decline of phosphorous sources, and whether there should be different language regarding of urine. It was decided to define and treat urine and solid human waste the same, and add some more explicit restrictions requiring further treatment, examples being composting and fermentation."
(www.goma-organic.org/wp-content/uploads/...MA_Asia_WG_Seoul.pdf)

Regards,
Gerhard

Dear Marijn,
The complete reference for Odlare et al., 2000 is:
M. Odlare, M. Pell, P.-E. Persson. 2000. Kompostanvändning i jordbruket : en internationell utblick (In Swedish). RVF utveckling, [1103-4092]; 2000:6. Svenska renhållningsverksföreningen. Malmö, Sweden.
This report is however not available on the net, as the organisation has changed name since the report was printed.

If you want the report, you can probably get it from Monica Odlare att Mälardalen University or from me at Swedish University of Agricultural Sciences.
Best regards,
Håkan

Dear Gerhard,
Thanks for a detailed and good description of the IFOAM regulations and thanks for correcting me. I was wrong in writing that human excreta is allowed by the IFOAM. After studying the regulations better, I should have worded it "use of human excreta are prohibited by IFOAM, but standard-setting organizations may make exemptions provided that detailed sanitation requirements preventing the spreading of pests, parasites and infectious agenst are established." I guess that it was this exemption that the Swedish organic branding organisation KRAV used for many years and I think that it is a real pity that, due to the present EU regulation, they are not allowed to use it any more.

Detailed sanitation requirement have been published by the WHO in their guidelines on "Safe use of wastewater, excreta and greywater" volume 4 "Excreta and greywater use in agriculture"

They generally recommend that a Hygien Risk Assessment should be made for the systems, but they also give the detailed sanitation requirements which I have upload with a file. From these it is:
1) obvious that source separeted urine poses a very small risk.
2) considering that some crops, also food crops, has a long growing period and many others, like sorghum, millet, rice etc are cooked before eating, actually many crops can according to "Practical guidance on the use of urine in crop production" www.ecosanres.org/pdf_files/ESR2010-1-Pr...nCropProduction.pdf, pages 24-28 be fertilized also with urine which has not been stored, which otherwise is the recommended treatment for sanitization. BUT NATURALLY FOR CROPS EATEN RAW AND WHICH MIGHT COME INTO CONTACT WITH THE URINE OR THE URINE FERTILIZED SOIL, THE URINE SHOULD BE STORED at least FOR 6 MONTHS AT 20 DEG C before fertilization.

For faeces, the FAO guidelines give several options. For three years, while I had a UDDT in my house, I used the option of composting for at least a week at more than 50 deg C. I have a well insulted food waste compost. By feeding and turning it I got the temperature up to 50 deg C. When confirmed that I had at least 50 deg C, I added the faeces in the center of the compost. The faeces got a temperature of 55-60 deg C within a day. I waited about 5 days and then I turned it, but still keeping it in the center of the compost. This I consider a very safe sanitization.

However, as Ralph points out, it is a bit tricky to reach 50 deg C in small composts. It takes good insulation, experience and taking good care of the compost. Thus, I generally recommend the storage option given by WHO. In Sweden this means to store the faeces for two years, and then you can compost them a low temperature. After this they are a nice looking and very good fertilizer.

I really hope that IFOAM will allow excreta or at least urine as a fertilizer not only as an exemption but as a general rule. One important reason for doing this is that source separated human urine is by far the fertilizer around with the lowest cadmium (Cd) level. It has a cadmium level of just about 0.6 mg Cd/kg P, which is extremely low.

One company sells fertilizers declared low in Cd in Sweden. They are guaranteed to have less than 12 mg Cd/kg P. The average level in Europe is about 80-85 mg Cd/kg P. Manure from both conventional and organic farms in Sweden have Cd levels of 7-18 mg Cd/kg P.

EFSA (European Food Safety Authority) in their scientific opinion on cadmium in food www.efsa.europa.eu/en/efsajournal/pub/980.htm states that "The mean exposure for adults across Europe is close to, or slightly exceeding, the TWI of 2.5 µg/kg b.w. Subgroups such as vegetarians, children, smokers and people living in highly contaminated areas may exceed the TWI (Tolerable Weekly Intake) by about 2-fold. Although the risk for adverse effects on kidney function at an individual level at dietary exposures across Europe is very low, the CONTAM Panel concluded that the current exposure to Cd at the population level should be reduced."

The fact is that you can not find any fertilizer, organic or conventional, that is even close to urine when it comes to being low in Cd. Thus, my conclusion from this is that urine should be recommended as a fertilizer for food crops, out of health and sustainability reasons! I hope that IFOAM will find this also.

Sustainable regards,
Håkan

Dear Hakan,
dear all,

Urine is low in Cd. Costs to eliminate toxic Cd are estimated up to 100 €/MT. Vegetarians are highly exposed to Cd. Phosphate containing high levels of Cd will become sold as cheaper fertilizers for poor countries. More expensive Cd-"clean" phosphate rock will be used in high developed nations. Additional problems are gypsum at the retrieval of phosphate from the rock and natural radioactivity.
EC Commission decision of January 2006 allows Sweden to set lower limitations of Cd content in fertilizers (100 grams / metric ton eq 0.1 mg / kg)
(eur-lex.europa.eu/LexUriServ/LexUriServ....129:0019:0024:en:PDF). But EU is only responsible to regulate mineral fertilizers (chemicals). Regulations concerning organic fertilizers are national law, not community law. National, regional and EU government regulations supersede EU Organic Standards and may vary from member state to member state.
I believe that wording of IFOAM standards next year will be: "Human excrement shall be handled in a way that reduces risk of pathogens and parasites and shall not be applied within six months of the harvest of annual crops for human consumption with edible portions in contact with the soil."
But eg. German "Düngemittelverordnung" (fertilizer regulation) must also be changed to allow application in Germany.
I am IFOAM affiliated and will ask IFOAM Head Office, EU-Group and FIBL to check the correctness of my remarks.

Regards,
Gerhard Pelzer

Note from Moderator to "anapaine": this post is off the topic of this discussion. Please can you explain the linkages of your post to the discussion "Use excreta compost only for non-edible plants (preferably)?"
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Compost is organic matter that has been decomposed and recycled as a fertilizer and soil amendment. Compost is a key ingredient in organic farming. At the simplest level, the process of composting simply requires making a heap of wetted organic matter (leaves, "green" food waste) and waiting for the materials to break down into humus after a period of weeks or months. Modern, methodical composting is a multi-step, closely monitored process with measured inputs of water, air and carbon- and nitrogen-rich materials. The decomposition process is aided by shredding the plant matter, adding water and ensuring proper aeration by regularly turning the mixture. Worms and fungi further break up the material. Aerobic bacteria manage the chemical process by converting the inputs into heat, carbon dioxide and ammonium. The ammonium is further converted by bacteria into plant-nourishing nitrites and nitrates through the process of nitrification.
BioActive Cocopeat is also a recycled organic product originating from pure cocopeat. Cocopeat comes from the husk of the coconut and is widely used around the world as a superior high quality growing media due to its unique aeration and water-holding qualities.You can try coco-peat for your plants.

Some of the elements in the discussion will become more clear when definitions are correctly established. With human excreta (urine and faeces) it is assumed that these are fresh or rather fresh, being the reasons for restrictions.

From the discussion I gather the following: When fresh human faeces are composted over a period one year below 20 degrees Celsius (1Y<20C) it can well be applied for forestry and similar plant growing, causing minimal risks. Similar with fresh human faeces which are composted half a year over 20 degrees Celsius. The nitrogen binding in fresh human faeces increases with the application of fine dry clay soil in the UDDT.

Sewage is often city sewage and can include all sorts of undesirable elements such as chemical and metals. Obvious specific rules apply for the use of city sewage. It is also not similar as human excrements although they will contain some.

Effluent from biogas reactors is also different and can not be called fresh human excreta since it has been processed already. In this case one needs to now the retention period of the biogas reactor and if it is an environmental temperature or thermophilic process. With a minimum one months retention and high temperature the effluent is nearly 100% safe to handle.
One issue related to the application on crops is the amount of rain and sun that will pass between the latest application and the harvesting. Dust from the ground during harvesting can spread parasites to the crop, which is the main risk. Generally the plant breaks down the nutrients and converts them to crop.
Having a list of definitions associated with the standard will be helpful.

Dear Hakan,
dear all,

IFOAM regulations for the use of human faeces as fertilizer have changed. Now the use is allowed with restrictions. On August 12, 2012, the new version of the IFOAM Norms, Version 2012
www.ifoam.org/about_ifoam/standards/norm...ust2012withcover.pd, has replaced former Version 2005. EU-Eco-Regulation are still not updated and not mention human faeces in the positive list of allowed fertilizers. National legislation may take precedence and make the use of urine and faeces in principle impossible, whether for organic farming or conventional farming techniques.

New regulation on human excrement as fertilizer :
4.4 Soil Fertility and Fertilization
4.4.5 Human excrement shall be handled in a way that reduces risk of pathogens and parasites and shall not be applied within six months of the harvest of annual crops for human consumption with edible portions in contact with the soil.

"The IFOAM Standard is intended to be an internationally applicable organic standard that can be used directly for certification. It will also be a highly recognized, globally applicable standard.The IFOAM Standard now offers a global platform for organic standard setters to discuss, exchange, negotiate and compromise on detailed standards, thereby taking over the role that the IFOAM Basic Standard had in the past in this regard." (IFOAM, August 12, 2012)

I am relieved that the changes have already taken place, and not next year, as I announced in May.

Regards,
Gerhard

Dear Gerhard and everyone,

It is excellent that these codes are changing.

Nonetheless, those rules refer to human feces and it is correct to be concerned about their use in agriculture, BUT what we need to raise consciousness about is that, after the treatment we give feces (long storage, drying, composting, baking in solar ovens, etc.), they stop being feces. Recognizing the cyclical nature of these ecosystem processes, feces should be seen as a temporary state, not a permanent state. In a practical sense, we can define this temporary state as the time in which this material may potentially contain fecal pathogens, especially helminth eggs which are the most persistant pathogens and can be seen under the microscope (presuming the users have such intestinal worms).

If we analyze our treated (ex) feces, what we would find is fungal hyphae, soil bacteria, humic acids, undigestible fibers, etc., which in no way constitute feces or any health risk.

If we turn back the clock on the material, we find plants growing in soil, which optimally included the decomposed feces of animals (potentially including those of a species called Homo sapiens).

So these rules, guidelines, and laws should just stipulate what is proper treatment of feces and testing of the final product, after which we have a safe compost that can be used however we like.

Best wishes,
Chris Canaday

Dear Chris,
Dear All,

We should distingish between a vision to be established and everyday practice that can work ok. If we learn to feed the soil in a vegetable garden with chopped fresh veggies we can boost productivity. See youtu.be/pSShndKiA3g for reference, this really works. Such increadible productivity is based on the understanding that plant roots take up bacteria alive and digest them (as it has been shown e.g.for E-Coli by excellent international universities).

With proper land use we do have plenty of good use for excreta compost for reforestation with edible trees that produce massive amounts of food and fodder like Moringa Olifera. Handling of excreta in more densely populated areas (where there are rather tiny gardens if at all) should be in the hands of a professional local composting organisation. Those living in the rural can do otherwise easily with Arbo Loo and urine utilisation. When there is collection for a composting site the site can be in a reforestation zone and shift to the next later. Ecosan for low density rural settings is really simple, at TUHH we work towards serving 100.000 people in an adequate way and at a low price. We found the ways and aim at tolet producers and adequate projects now.

Kind regrads

Ralf