The importance of poo

"1% of wastewater is waste. The rest is wasted water."

I can't remember why now that poo got on to my list of potential blog topics, but last night we watched the last program in the excellent The Chemical World series on the ABC, which revived my enthusiasm, so today I did a bit of internet wandering and actually became a tiny bit downhearted, but not a lot.


There is actually more to this topic than what was on the TV last night, but let's start there.


The part of the program which was relevant was on phosphorus, about which I learnt a lot. although I can't say I understood it all. I sort of knew some of it but what I did remember from my own experience, very clearly was an experiment that went wrong in our chemistry class at school. I cannot remember what the experiment was, but I know it involved phosphorus being added to something and what happened was a mini explosion which created clouds of gas and the whole class rushing out into the corridor, followed by the gas. I feel for the poor teacher now. She must have been mortified. She was only young - it might have been her first job. I think her name was Miss Poulson. Nobody was injured from all of this and I think we all thought it was a bit of a lark - yes we used that term back then. So yes I sort of knew it was a vaguely dangerous thing and also that it sometimes glowed. And actually one of the things I learnt today was that it's a component of napalm, and is also in matches. Which I might have known but I'm not sure.

The name Phosphorus is Greek of course, from two words which together mean light bearer and which refer to the planet Venus as the morning star. They personified Phosphorus as one of their lesser godly beings. In latin it's Lucifer and also refers to the planet Venus as the morning star. Which is etymologically really interesting isn't it? Venus is a rather hell like planet, and we also know that Lucifer is one of the names the devil gets called. But, of course, Lucifer was also an angel originally. The word 'lucifer' is also connected to light - lucid must derive from it surely? All quite appropriate anyway - Venus as a hell and yet as a bright light in the sky.


Back to the chemical phosphorus though. Did you know, for example, that .7% of the human body is made up of phosphorus. It is one of the crucial elements for the existence of life. Without phosphorus there is no life. You cannot create and maintain life without it. But it's in short supply. I believe 1% of the earth's crust is made up of phosphorus and 50% of that is in Arab countries according to Wikipedia, although it then goes on to say, and this doesn't quite make sense, that Morocco produces 85% of the global supply. China, Russia and the USA also have deposits. There were all those islands like Nauru which had large deposits of guano, but these are now largely exhausted, and so they are now mining rock phosphorus. The annual demand, again according to Wikipedia I think, is rising nearly twice as fast as the growth of the human population.


"The extraction of phosphate rock is not only a very toxic and energy intensive process but it’s also a non-renewable resource that’s predicted to reach peak supply in 2033. After that the price of phosphorus will increase significantly, bringing the price of food up with it. According to the Soil Association’s peak phosphate report, without mined phosphate, crop yields in conventional farming could be reduced by half." Rachel Dring - Sustainable Food Trust (UK)


Why will it bring up the price of food? Because phosphorus is, of course, a prime ingredient in fertiliser. Plants - like us - need phosphorus to grow and they get it from the soil. They do not put it back. All of which is quite dire.


What to do? Well, as I said phosphorus is in the human body and every day we excrete it in our waste - primarily in urine I believe but also in fecal matter. Now the human race has been using human excrement as fertiliser for thousands of years, and in many poorer parts of the world it still is being used. I sort of did for a while when we lived in Donvale, where we had a septic tank system which included a massive, compulsory sand filter. It was very deep - they had to blast out the hole which was quite long and wide, and was filled with varying grades of sand, with soil on top. I used it as a vegetable garden and that particular vegetable garden was indeed the most productive of all the vegetable gardens I have had over the years. I worried mildly about it, but we seem to have survived. My worry was completely uninformed and mostly just based on the normal association in the mind of poo with disease.


Historically human, and animal excrement has been used as manure since the dawn of time. Early on bone ash was also used - this too is a source. And I suppose that animal bone ash may well be a constituent of the fertiliser blood and bone. A German called Hennig Brand was the man who localised phosphorus in urine. It's interesting isn't it that something that can indeed cause disease and death - and certainly did before the invention of the flush toilet and efficient sewage systems can at the same time be life-giving.

We all know of the importance of washing hands after a visit to the toilet, the dangers of cholera, typhoid, dysentery and all manner of other diseases, emanating from e-coli and excrement generally not to mention the parasites. Prior to flush toilets and sewers the excrement was buried or thrown into the rivers and the sea, and thence into the drinking and washing water. Some was directly put on to the land as a fertiliser. As happens with animal manure today. Mostly animal manure is not treated and yet it is a vital part of the gardener's tool kit.


Today in the developed world sewage is largely processed in vast sewage plants. Progress is being made in separating out the useful phosphorus laden bits, and also by returning the water to drinkability, but we haven't got there yet. Many worry about the amount of pharmaceuticals, metals and hormones that may be present in the human waste, and which could cause disease and birth defects. Here the evidence gets a bit murky. As some point out, animal manure is not treated in the same way as human excrement, and yet many of the animals producing this manure have been pumped with antibiotics and hormones too. I also saw that the process of treating the sewage, gets rid of 99.9% of the pathogens. The solid waste which is used as manure - called biosolids - is processed through reactors which also produce renewable energy.


Many Aussie farmers swear by biosolids. It is less soluble than artificial fertilisers they say, and therefore stays in the soil longer. As well as phosphorus there is nitrogen and potassium too. The program I saw last night was largely optimistic that the mined phosphorus could eventually be replaced by products emanating from human waste - and there's a lot of that. Whether it be from redesigning the toilets themselves, or processing the waste. It certainly shouldn't be dumped into the sea where it causes algae blooms which basically kill everything. And then I saw someone say that up to 22% of the world demand for phosphorus could be produced by recycling human waste. Which probably isn't enough. And the really gloomy say things like:


“I don't think that the fundamental principle of mixing shit with drinking water and then paying a lot of money and using a lot of energy to remove the shit from drinking water is necessarily the best idea,” Rose George/Wired


Sometimes you think you can't win don't you? But scientists are amazing people and there seemed to be plenty of optimists on the TV last night seeing solutions emerging.


"you aren't what you eat - you are what you don't poop." Wavy Gravy


Although what you do poop (as the Americans say) is eventually what you eat perhaps.


Which brings me to the other wonderful aspect of poo - the poo transfer. Not only does poo cause disease, it can also cure it. Indeed this too has been going on since forever. Doctors from ancient times have prescribed poo in various forms as cures for all manner of stuff. They have also spent some time examining poo as a diagnostic tool. And this is certainly still done today. It's a standard test for all manner of digestive diseases.


Then there's the poo transfer to boost the human biome, and to defeat C-difficle - potentially the only way to do so. The human biome has been discovered to be so important that these days, almost routinely babies born by Caesarian section are smeared with some of their mother's poo so that they get the biome in the poo that they would otherwise have encountered in a natural birth. It boosts the immune system and may help with all manner of other diseases.


Poo is simultaneously life and death giving. In poor countries it is often burnt as fuel - doubtless producing noxious gases as it does so, some of which go into the food being cooked over the fire. The dung is also used to coat dwellings - like plaster or mud - and this probably releases gases as it dries, not to mention passing on whatever nasties it may contain to the people who handle it.


It provides endless amusement to small children and larger ones too as well as major disgust and phobia. Maybe it's the word itself which is so attractive to children - that soft plosive 'poo' so easy to say and so comforting somehow. Like Winnie-the-Pooh.

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