Human excreta is made up of urine and faecus. Humans produce 120-200
grams of excreta per day. It consists of 80% water and the rest is mostly
organic matter. Those having toilets generally add a lot more water by
mixing it with Urine, washing ourselves, as well as washing the toilet.
Those who do not, generally leave it to the nature to take care of it.
FAECES
Human faeces
naturally contains high amounts of bacteria. It also contains pathogenic
bacteria, viruses, protozoa or helminthes. Thus many diseases get
transmitted through faeces. Because of this it is considered a problem and a
risk to handle. Therefore waste disposal and sanitary systems have
increasingly tried to reduce human contact with faeces.
Most of the 2,00,000 tonnes of faeces that we produce every day
ultimately finds its way to water bodies like river and the sea. Even though
there we have effluent treatment plants, at a high cost to the exchequer,
there is still large scale contamination. We have ended up contaminating
groundwater, and the sea.
On the other hand if we look at this waste as nutrients, it could help us
increase food security and agriculture. Human faeces are rich in
phosphorous, potassium and organic
| matter. Thus they make good soil
conditioning material. In fact, by failing to return natural fertilisers,
such as human excreta, back to the land, we are depleting soils of
nutrients, resulting in the use of artificial fertilisers, and the increased
use of pesticides..
URINE
Urine is a by-product
from the body's function of balancing liquid and salts. The average person
produces about 500 litres of urine per year.
Urine is generally sterile, though it contains some bacteria after
excretion. Cystitis, typhoid fever, schistosomiasis or leptospirosis can be
transmitted through urine.
Urine is a high quality, low-cost alternative to commercial fertilizers.
It is especially rich in nitrogen and also contains substantial amounts of
phosphorus and potassium. According to estimates if urine of about 30 crore
people in India who have toilets could be collected, it can produce 1.65
million tones of fertilizers valued abot Rs. 800 crores per annum.
Estimated excretion of
nutrients per capita in India
(from Jonsson & Vinneras, 2004)
Total Nitrogen (in kg/cap, yr) - 2.7
Total Phosphorous 0.4
Nitrogen in urine- 2.3
Nitrogen in faeces- 0.3
Phosphorous in urine- 0.3
Phosphorous in faeces- 0.1 Source: www.ecosanres.org |
Thus we can see that what we
consider waste, does contain essential nutrients which if ploughed back into
the soil is extremely beneficial. The WHO has declared that Soil is a natural
sanitization system, but provides that 1. The persons handling the waste
should have adequate protection. 2. The waste should be covered by 25 cm of
soil and 3. No root crops should be planted (WHO, 1989). |
Novel schemes include a plan to build an artificial wetland
at a jail in Mombasa, Kenya, to process sewage from 4,000 inmates that now
flows untreated into a creek, or ponds in South Africa where algae purify
waste and are then used as fertilizer. "About 90% of the sewage and 70% of
the industrial waste in developing countries are being discharged untreated
into water courses," said Achim Steiner, head of the UN Environment
Programme (UNEP). Sanitation goals seen
slipping solution may lie partly in nature -Alister Doyle [C.eldoc1/d70d/18mar08mnt1.pdf] The toilet at the Mumbai Municipal Corporation's Versova has no flush tank. The
pumping station recycles sewage water so that it can be used for gardening and
bathing. -- Tank the sewage in your tub by Anush Chopra. DNA, Mumbai 7th
December, 2005.
Treated domestic waste water helps production of carp fish. The
nutrients in the sewage are used to develop food organisms. - Domestic waste
water as fish food, Down to Earth, 15th November 2007. | Reuse of Faeces and Urine from Ecological Sanitation - Niall
Boot
This brief outlines in more detail the methods used to render both faeces
and urine safe for agricultural use and provide guidance on application
methods. Excreta from one person can provide nearly enough nutrients to
produce approximately 250kg of cereal per annum (Strauss, 2000). This is one
of the reasons the resource has been used throughout history in both
aquaculture and agriculture (the by-product from ecosan is usually used in
the latter). Historically excreta has not always been treated before use,
correctly operated ecosan allows excreta to be reused whilst minimising
health risks.
[
C.eldoc1/d70d/reuse-faeces-urine.pdf]
| This section is based on
Guidelines on the Use of Urine and Faeces in Crop Production by Jonson H, .
EcoSanRes Publication Series. Report 2004-2. Stockholm Environment Institute:
Stockholm. Sweden. Available from
www.ecosanres.org. |
|