In the Millennium Development Goals, the target has been set to halve the proportion of people without access to safe drinking water and adequate sanitation by 2015 (Zimbelman and Lehn 2006). The goal is justified as, 1,1 billion people in 2000 had no access to safe drinking water and 2,4 billion to adequate sanitation (WHO, UNICEF, WSSCC 2000). Lack of sanitation causes approximately 250 million cases of water-related diseases and five to ten million deaths annually in developing countries. Even though the developing countries suffer the most, the international community also faces payments of hundreds of billions of US dollars yearly due to diseases like diarrhoea, schistosomiasis and cholera. Medical or environmental issues, but rather the overwhelming poverty that these countries are faced with, restrain the solutions to the epidemics. While governments lack the resources to provide people with basic health care and sanitation, people are uneducated about the linkage between sanitation and diseases. (Hollander 2003, 101-102)
In a world, where water is becoming a scarcity and more and more expensive, and while governments fail to provide safe drinking water and sanitation facilities for their citizens, alternative approaches are needed. Dry sanitation offers a sustainable solution for the improvement of sanitation for the disadvantaged. Conventional water closets consume a lot of fresh water for transportation and purifying wastewaters. Dry toilets function without water, which has become a scarcity in the regions battling with sanitation problems. (Zimbelman and Lehn 2006) Eco sanitation has been acknowledged by the UN (Langergraber and Muellegger 2005) and dry toilets are presented to different kinds of communities in several countries around the world, such as South-Africa, Zambia, Mexico, Romania and Vietnam (Rautanen ja Viskari 2006; Jensen et al. 2008). Furthermore, as the need for articial fertilizer has increased and people are not able to afford it (Guzha et al. 2005), dry toilets provide a lucrative fertilizer turning waste into resource (Zimbelman and Lehn 2006). In Sub-Saharan Africa, the annual production of human excreta per person is enough to cover the amount of artificial fertilizer needed for the annual food production of the individual (Winker et al. 2009). Urea is also considered one of the most important industrial nitrogen producing fertilizers (Heinonen-Tanski et al. 2007). In dry toilets, the faeces are collected into two chambers. When the other one is full, it is left to compost and the other chamber is put to use. After every use organic material, such as sawdust or bark-mulch, is added. In warm temperature and adequate airflow, faeces are degraded by fungi and bacteria. (Zimbelman and Lehn 2006)
Possible challenges with dry sanitation are the stigma of using human faeces as a fertilizer in order to produce food, and participation of the recipient for safe use and ensured ownership of the toilet. (Heinonen-Tanski et al. 2007, Peasey 2000) Water closets are usually considered to be a symbol of modernity, so dry toilets can be perceived as a sign of inadequate progress. Yet, in some areas sanitation is perceived as a secondary matter, while dry toilets are wanted for the appearance reasons only. (Langergraber and Muellegger 2005, Folke 2006) Dry sanitation is said to work better in the rural areas, where the space is not so limited, opposed to urban, densely populated urban settlements. (Zimbelman and Lehn 2006) Nevertheless, dry sanitation should be considered as an option in suitable areas as a provider of improved sanitation, environmental development and increased food supply.
References:
Folke, S. (Ed.) and Nielsen, H. (Ed.) 2006. Aid Impact and Poverty Reduction. Palgrave MacMillan. New York.
Guzha, E., Nhapi, I. and Rockstrom, J. 2005. An assessment of the effect of human faeces and urine
on maize production and water productivity. Physics and Chemistry of the Earth 30. 840–845.
Heinonen-Tanski, H., Sjöblom, A., Fabritius, H. and Karinen, P. 2007. Pure human urine is a good fertiliser for cucumbers. Bioresource Technology 98. 214–217.
Hollander, J. M. 2003. The Real Environmental Crisis: why poverty, not affluence, is the environment’s number one enemy. University of California Press Ltd. England/USA.
Jensen, P.K.M., Phuc, P.D., Knudsen, L.G., Dalsgaard, A. and Konradsenc, F. 2008. Hygiene versus fertiliser: The use of human excreta in agriculture –A Vietnamese example. Int. J. Hyg. Environ. Health 211. 432–439.
Langergraber, G. and Muellegger, E. 2005. Ecological Sanitation—a way to solve global sanitation problems? Environment International 31 433– 444.
Rautanen, S.L. and Viskari, E.L. 2006 In Search for Drivers for Dry Sanitation. Land use and water resource research. Tampere Polytechnic University of Applied Sciences. Tampere, Finland.
Peasey, A. 2000. Health Aspects of Dry Sanitation with Waste Reuse. Well Studies in Water and Environmental Health. Task No 324. London. UK.
WHO, UNICEF, WSSCC 2000. Global water supply and sanitation assessment 2000 Report. Geneva, Switzerland.
Winker, M., Vinnerås, B., Muskolus, A., Arnold, U. and Clemens, J. 2009. Fertiliser products from new sanitation systems: Their potential values and risks. Bioresource Technology 100. 4090–4096.
Zimbelman, M. and Lehn, H. Contribution of dry sanitation to the MDGs and a sustainable development. Vortrag auf der 2nd International Dry Toilet Conference: Dry Toilet 2006. Tampere, Finland, 16. - 19.08.2006
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