My French granny says it is more hygienic to poo in a big hole in the garden, like she did when she was growing up, than it is to go inside. Is this true? She also said that in olden days, people collected pee and used it to make plants grow better. Could we do this now?
There鈥檚 a dispute over whether the practice is healthy or harmful, but there鈥檚 certainly a lot of information out there 鈥� Ed
鈥� We need to remember just how bad it was before modern sanitation. London experienced The Great Stink in 1858 鈥� hot weather that exacerbated the smell of untreated excrement in and around the Thames 鈥� which led to plans for the treatment of human and industrial wastes.
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So maybe it is best to avoid using the garden outside an isolated dwelling, and certainly not in towns, let alone cities. Diseases we rarely hear about today such as typhoid and cholera were rampant before sanitation. So please, do your business inside and flush it away for treatment.
鈥淟ondon experienced The Great Stink in 1858 鈥� hot weather that exacerbated the smell of excrement鈥�
Secondly, urine can be valuable or harmful depending on how it is handled. It is loaded with nitrogen and phosphate, which fertilise plants. If it can be collected separately from other waste, it can easily be treated and farmers can spread it on crops.
But urine is difficult to remove from wastewater, and it is harmful if discharged into waterways, where it fertilises algae. Decomposing algae consume a lot of oxygen, creating dead zones in the waterways.
You can spread your urine thinly in your garden and watch your plants grow. However, if it is concentrated, it can burn the plants.
Peter Jacobson, Davis, California, US
鈥� When I was growing up in the 1950s, I often visited a cottage that had an earth closet. This consisted of a bucket under a wooden seat, with a container full of soil from the garden beside it. Having used the bucket, you shovelled some soil on top. The contents of the full buckets were later buried in the garden, which produced wonderful, very large vegetables. In past centuries, this 鈥渘ight soil鈥� was collected from toilets in towns, and was used to provide fertiliser for market gardens.
Greg Nuttgens, Bridgend, Mid-Glamorgan, UK
鈥� Your granny is right. At the very least, defecating outside prevents our dung鈥檚 disagreeable odour from tainting the air inside. Indeed the word 鈥減oo鈥� comes from the French verb 鈥�puer鈥�, which means to stink. We instinctively connect this bad smell to the risk of disease, which is why it is so off-putting even though everyone does it. Some microbes do get wafted into the air we breathe, but too few to make us sick.
No matter how carefully we wipe ourselves, some microbes will get onto our hands and hence onto any surface we then touch. They can also be splashed from the lavatory bowl when we flush it, and from the bidet or basin when we wash ourselves. If we or other people then touch these surfaces and pick up the microbes, they could get transferred to kitchen surfaces and so on to food.
鈥淒efecating outside prevents our dung鈥檚 disagreeable odour from tainting the air inside鈥�
But a big hole in the ground contains no water that can splash. The outdoor air disperses the smell more quickly. The dung can be covered with soil to trap the smell and prevent accidental contact. If the home has an outside tap, then this and the spade handle will be the only thing our dirty hands might touch, and any splashes we make while washing them will be away from indoor surfaces.
Before flushing toilets were invented, folk would do their business in chamber pots, which they would empty onto the streets below. They were clearly hygiene conscious back then, for it is said that the English word 鈥渓oo鈥� comes from their warning cries of 鈥�濒鈥檈补耻!鈥� 鈥� French for 鈥淲ater!鈥� 鈥� as they tipped it out, so as not to surprise passers-by.
Defecating into the ground is also better for our insides. The usual sitting position on a toilet can put a strain on our bowels as we open them, and lead to health problems. But going in a hole requires us to squat, which allows our bowels to open more easily.
We certainly could water our gardens with urine. It is rich in salts and minerals that plants find useful. It is also especially rich in urea, a more complex waste substance that soil microbes start breaking down. Plants can then take up these nutrients through their roots, and use them to grow and thrive.
Len Winokur, Leeds, UK
鈥� Excrement was collected in barrels at the end of streets in 18th-century London and shipped up the coast for the alum industry around Whitby.
Derek Morris, Harpenden, Hertfordshire, UK
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