View Full Version : human waste as fertilizer

Sep 22nd, 2006, 05:24 AM
A researcher with Queensland's Department of Primary Industries (DPI) says it is environmentally safe to use processed human waste as a fertiliser on food crops. The CSIRO is coordinating the research as part of a four-year nationwide project. Queensland project manager, Dr Mike Bell, is preparing his final report.

He says the processed waste is the by-product of the water recycling process and can be used safely.

" ... we're starting to see potassium decline and we're seeing trace elements decline, so it makes sense."

One of the leading campaigners against water recycling in Toowoomba, Rosemary Morley, says farmers will find it difficult to sell their produce if they use recycled human waste to grow food. "People are just not prepared to go anywhere near using their own excrement, whatever treatment's gone to it, because people know that you usually don't go near that," she said.

Sep 22nd, 2006, 05:35 AM
What do you think, Eve?

:o I'm not sure I know what to think.

Sep 22nd, 2006, 05:57 AM
Roxy, well I know that human waste has been used for very many years in the East, but we don't know if there has ever been research on whether health has been at risk. As for human waste being processed for use as fertilizers, or human waste being used for drinking water - in both cases it is probably just the thought that is offputting. Someone who knows something about this, told me that the end result of drinking water, for example, has gone through many processes of filtering, and is probably cleaner than the tank water we drink, or even tap water. I hear people say, "well you won't catch me drinking it"!

But would I drink this water personally? - I'll probably be a coward and buy bottled water! ;). At the moment I use tap water and magnetise it to draw out all the impurities.

Sep 22nd, 2006, 06:02 PM
My family once had human waste spread on our land. Wow, did the grass grow well that year! It smelt though (that was before the law changed about having to plow in smelly fertilisers).

Sep 22nd, 2006, 07:55 PM
I'd be a lot happier to use this than animal fertiliser. If we need it to grow our food then we should provide it. :)

Sep 23rd, 2006, 12:03 AM
Its funny you should mention this Wessex Water tested a version of this called BIOGRAN which happened about 6 years ago.

It was human orgaic bumb dung then it was pushed through machines to create a cake, this in turn was baked at 2000 degrees then which dried in to pellets.

I had some it was great, but could only be used on grass, non direct contact crops, eg not for spuds, carrots, turnips etc.

Fine for fruit trees, etc.

I have not spotted the product on general sale the only reason I know about it I was a temp for them.

Sep 23rd, 2006, 12:10 AM
Human Organic Bum-dung - I think you've got yourself a marketing dream there Snaffler! ;)

Sep 23rd, 2006, 05:00 PM
its not a new idea. Google humanure for lots more.

Sep 26th, 2006, 11:59 PM
Why do people find animal dung to be so much more attractive than human dung? I don't get it.

Sep 27th, 2006, 12:04 AM
Nor me. Convention?

Sep 27th, 2006, 12:41 AM
People used to use it all the time, as long as the food is boiled before eating it then it should be fine.

Sep 27th, 2006, 12:54 AM
Someday it will probably be necessary to do this everywhere and Australia, with its seriously degraded soil, might be the first to have to do so.

Sep 30th, 2006, 12:01 PM
Why do people find animal dung to be so much more attractive than human dung? I don't get it.

Human waste has to be treated to kill parasites and pathogens which can easily be transmitted, whereas horse manure, and cow manure, from field grazing animals, should be relatively safe to use just as it comes. Less smelly too. Have you compared the smell of a horse poo to the smell of a human poo, particularly a meat eating human poo?
There is a role for using human poo, from composting toilets etc, but it is important that it is treated by proper composting methods. Composting naturally heats the compostable materials to a fairly high temperature so hopefully that would kill parasites and pathogens.
If you study history you will remember many diseases like cholera were transmitted via open sewers. Cholera wiped out whole populations in some areas. Unfortunately it is coming back in some war zones today because sewers have been bombed.

Sep 30th, 2006, 03:46 PM
I assumed that it would be treated! ;)

Oct 1st, 2006, 03:45 AM
I recently read a book that addressed this topic (it's relatively new, from the U.S. and deals with waste here) but I can't think of its name. Anyway, human waste contains a lot of heavy metals that we don't want being absorbed into the plants we will then eat (think mercury for example). In some counties in the U.S. the "safe" levels of metals in fertilizer have been increased in order to allow the use of human waste. When I think of the name of the book I'll post it - it was a good read.

If anyone here in the U.S. has spread Milorganite on their lawns then they have already used human waste.:)

Oct 1st, 2006, 04:58 PM
as long as its vegan human waste, any other kind :eek:

Oct 19th, 2006, 06:55 PM
the problem of human waste si like dianevegan all the heavy metals that are contained in it but there are also problems if the human manure utilized is from people who take medicinals.
I read some articles on that and it also takes something like 2 years for the manure to be ready to be used.
It'll be a good way to recycle all the human wastes.
I also read an article about ESA (european space agency) about a system that they are finalizing to provide food for the astronauts in the long missions where it's impossible to bring enought food in the shuttle. They recycle human manure and use it to cultivate seaweed (spirulina if i'm not wrong) that is the most effective way to produce proteins with few energy.

Dec 12th, 2006, 12:06 PM
Klutz "Why do people find animal dung to be so much more attractive than human dung? I don't get it."

For one, the animals commonly used have traditionally been fed a vegan diet, although this is no longer the case. Also, while the difference, in terms of supporting parasites that can infect humans, between plant waste composted in a compost bin made up of an animals gastrointestinal tract, and plant waste composted in a wooden compost bin, is greater than the difference between plant matter composted in a bovine animal as compared to plant matter composted in a human, there is a slight disadvantage to using human gi tracts of animal gi tracts, in terms of the number of parasites. Generally, parasites that live in plants won't live on animals, at all, but parasites that live in one animal are slightly more likely to be transmitted to the same animal (human to human) than they are likely to be transmitted between different animals (one vertebrate to another vertebrate). For example we are extremely unlikely to get a disease from earthworm poo (invertebrates) but almost as likely to get a disease from bovine poo as we are from human poo — assuming the same diet. Add in the factor of animal origin (in part) diet — and the risks go even higher.

Dec 29th, 2006, 02:52 PM
This was very informative! This is slightly off topic, but personally I don't understand why we don't use human shit (excuse the language:o) as manure instead of polluting the sea with it!:eek:

Some people do:


Not sure why this doesn't happen on a wider scale - however I believe in some countries human waste is already used in agriculture; I seem to remember bananas are sometimes grown that way.

Dec 29th, 2006, 06:19 PM
I think we should.

Unfortunately, the sewage systems of big cities, and suburban and rural septic tanks, become contaminated with all kinds of toxic materials that people pour down their sinks and flush down their toilet. It would be great if we could find a way make sure that nothing but urine, feces, and appropriately biodegradable toilet paper were flushed and poured down the sink. Then such matter would be great for non-food plants: golf courses, decorative gardens, growing plants for fiber, and wood, for growing cotton, hemp, etcetera.

I even think green manures for food could be grown this way. In other words, feed golf courses or buckwheat crops with composted human excrement. The cut the grass and the buckwheat and compost it, and use that compost in food-plant gardens and for food-trees (orchards). But again, due the law of physics saying perpetual motion is impossible, it would seem to me that human excrement could not possibly be produced in large enough quantities to feed all the food plants that would be needed to feed those same humans that produced the excrement. Even if, in addition, we used human bodies to feed plants, there still wouldn't be enough material — unless our population continuously declined. Eventually it would decline to zero, unless other souces of N were input into the system. It could, however, substantially reduce the amount of Haber Process N that was needed.

One way to make sure that nothing but urine and feces and TP get into sewage systems is to install 2 completely separate drain systems in large cities, draining into 2 completely separate sewage systems, and install 2 separate drainage systems in suburban and rural homes. This would mean doubling up on the the present system which has one for water going in and one for water going out. We would need an "excrement drain" system for urine, feces, and TP only, and a separate, and just as large and complex, "wash water drain" system for washing clothes, washing dishes, bathing with soap and water. If we want to save all the nitrogen and organic matter, the excrement system would have to be a new system that doesn't use the current porous tanks that allow lots of N to percolate into the surrounding soil (and not incidentally, into the ground water below). And we would have to find a way to clean toilet bowls that doesn't add dangerous chemicals to the excrement drain system. Simple plastic holding tanks that are pumped out once every 2 months or so might do. The composting could be done by a company that you paid to do it.

However since most people eat meat, this makes their excrement much more dangerous and much less desirable, even for golf courses.

Disinfectants would have to be used in very limited quantities, because they would slow down decomposition and add dangerous chemicals. The amount and kind of chemcials used to clean toilet bowls, would have to be controlled. And then how would you police people to make sure they don't flush all kinds of inappropriate materials down their excrement drain?

We do have some controls like this in industry, where manufacturers are prevented, these days, from pouring things into the sewage system, various industrial chemicals, that they used to pour into the sewage system. It works fairly well with industry. But of course some companies still circumvent the rules and dump things they aren't supposed to dump. But getting every individual in every household to comply would take a whole new level of social responsibility being instilled in people that are very different from past cultural values. It will take a long time. I think it could be done if people set their mind to it.

Dec 30th, 2006, 11:35 PM
I remember going to the sewage works as a child (and that was a long time ago!) to pick up dried human shit for our garden. I think it was in Rickmansworth.

Jan 1st, 2007, 03:22 PM

see point 4 how to install a compost toilet