Use excreta compost only for non-edible plants (preferably)?

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Re: Use excreta compost only for non-edible plants (preferably)?

Hello All
It’s Marko in France

I have been using compost from my toilet in the garden for the last 25 years. I also have had over 1 000 000 people go throw my compost toilettes in the last 5 years and have used this compost in agriculture. After reading the different posts in this thread I want to share this:

I believe that there are different qualities of compost.

*Anyone can make a "leave it in a pile/heap compost". This compost I would not use in agriculture. It is perfect for bio-mass reconstruction and reforestation i agree.

*Then there is compost that is managed, it is made in a controlled manner/ritual/respect. By creating certain basic conditions "biological terrain” with a N/C and O/H2O balance. I is then covered to keep the moisture in (70%) and insulated (to keep the heat in).
Only then will the compost heat up rapidly (+/-3days) to + 70°c, this can last 10 to 21 days witch is largely enough to kill of all pathogens and parasites. The temperature will tail off over the next 2 to 3 months (once this themophillic phase is finished) and during the next (mesophillic) phase, there are many divers populations of mycelium that will colonize and break down the different toxins by digesting them ( depending on the different types of cover materiel).
After this first cycle is finished (après 6 months) the compost is then turned, paying particular attention to take that that was at the exterior of the pile and placing it in the center of our next "andain" while re-oxygenating and re-humidifying to restart the whole procedure. Nb: urine can be used in the re-humidifying process.
At the end of this second cycle the compost is turned once aging and covered for a further year in to a maturing/ageing pile. The healthy compost is then used in agriculture. Here we have used a cycle of 2 years to sanitize and have living healthy compost.
*I believe that this process needs to be done by qualified people who have had adequate training and especially hands-on “experience in the field”.
*In the not to distant future, composting centers will and can use inoculations of different mycelium to decontaminate different types of toxicity including soil decontamination of any kind.

A must read “Mycelium Running” by Paul Stamets.

I would like to add a quick observation: I have noticed that there is a variable differnce in how fast the compost heats up and for so long, i used to put it down to the changes in atmospheric presure, but of late i have noticed that its got alot to do with my energy... If when i constuct the compost i am happy singing as i go, then the time it takes to heat up is quicker and it seems to stay hotter for a longer period...!

Thank you for reading
Biena vous
Marko
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  • Otterpohl
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Re: Use excreta compost only for non-edible plants (preferably)?

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
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

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  • canaday
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Re: Use excreta compost only for non-edible plants (preferably)?

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
Conservation Biologist and EcoSan Promoter
Omaere Ethnobotanical Park
Puyo, Pastaza, Ecuador, South America
inodoroseco.blogspot.com
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  • gerhard_dario
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Re: Use excreta compost only for non-edible plants (preferably)?

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...gust2012withcover.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
Gerhard Pelzer
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  • sjoerdnienhuys
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Re: Use excreta compost only for non-edible plants (preferably)?

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.
Sjoerd from The Netherlands.
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Some of my work on: www.nienhuys.info
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  • anapaine
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Re: Use excreta compost only for non-edible plants (preferably)?

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)?"

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.

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  • gerhard_dario
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Re: Use excreta compost only for non-edible plants (preferably)?

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
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  • HakanJonsson
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Re: Use excreta compost only for non-edible plants (preferably)?

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...InCropProduction.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
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  • HakanJonsson
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Re: Use excreta compost only for non-edible plants (preferably)?

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

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  • gerhard_dario
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Re: Use excreta compost only for non-edible plants (preferably)?

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
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  • Marijn Zandee
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Re: Use excreta compost only for non-edible plants (preferably)?

Dear Hakan,

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

rgds

Marijn
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  • HakanJonsson
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Re: Use excreta compost only for non-edible plants (preferably)?

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
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