Archive for October, 2012

I’m attending the Water and Health Conference (whconference.unc.edu)  in North Carolina to learn more about sanitation practices and to present my work on using human urine as a fertilizer. Below is excerpts of my poster:

Why human urine?

Use of human urine has demonstrated significant increase in biomass production compared to no fertilizer application in various plants, such as cabbage, tomatoes and beets (Jonsson, Stintzing et al. 2004; Guzha, Nhapi et al. 2005; Tidaker, Mattsson et al. 2005; Mnkeni, Kutu et al. 2008; Pradhan, Holopainen et al. 2010). Promoting its use could help alleviate 2 global crises by:

1.    Providing access to affordable fertilizer to sustain the increasing population’s calorie intake

2.   Providing adequate sanitation to the 2.6 billion people who lack access to proper sanitation

There is a limited understanding of the long-term impacts on the biomass production and  the soil’s chemistry. This experiment was developed to simulate nine years of continuous use of human urine as a fertilizer with spinach. The data presented in this poster is on the biomass and does not included the soil analysis.

Experimental design

The experiment was located in Arla, Himachal Pradesh, India and conducted from June to October, 2011.

Human urine collection

  • Undiluted human urine was collected  from 14 volunteers and stored in 10 L containers for 34 days at 25 degrees Celsius
  • During storage the human urine stabilized at a pH of 9
  • The human urine was assumed to contain 6 g of nitrogen per liter

Field set-up

  • Three fertilizer treatments and a control (no fertilizer) simulated nine years of continuous fertilizer application (years 1, 3, 5, 7, and 9)
  • Replicated 3 times in space (blocks) for a duration of 32 days

Statistical analysis

  • Randomized complete block design (RCBD)
  • Performed with SAS software using Duncan pairwise procedure.

Null hypothesis:

Human urine, mineral fertilizer and combination treatments will have equivalent biomass production in each simulated year

Results

Dry biomass produced per plant (Figure 3 and 4-A) from the human urine treatment was:

  • Significantly higher to the control for simulation years 5, 7 and 9
  • Not significantly different to the mineral fertilizer treatment, except for simulation year 9 where the average mass from the human urine treatment was significantly higher.
  • Significantly lower to the combination treatment at simulation years 3 and 5

Concentrations of nitrogen in the spinach tissue (Figure 4-B)were not significant different between the three treatments (human urine, mineral and combination) at increasing simulated year indicating the assumption of 6 g of nitrogen per liter was correct. All treatments had significantly  higher tissue nitrogen concentrations than the control.

Concentrations of sodium in the spinach tissue (Figure 4-C) from the human urine treatment was:

  • Significantly higher than all the mineral fertilizer treatments
  • Significantly higher than the combination treatment excepts for simulation years 3 and 9
  • Significantly higher than the control, except for simulation years 3 and 5

Moving forward

Farmers, especially those with out access to fertilizer, would benefit from using human urine as a fertilizer.  Spinach grown with human urine produced a greater biomass than no fertilizer and produced equivalent biomass to synthetic fertilizer. Human urine is combination with additional phosphate and potassium overall produced the highest spinach biomass. With continuous use, the survival rate of the spinach with the human urine treatment was higher  than with the mineral fertilizer. Salt sensitive plants may grow poorly in comparison.

References:

CRRAQ (2010). Guide de référence en fertilisation, Centre de référene en agriculture et agroalimentaire du Québec,.

Guzha, E., I. Nhapi, et al. (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.

Höglund, C. (2001). Evaluation of microbial health risks associated with the reuse of source-separated human urine. Department of Biotechnology. Stockholm, Royal Institute of Technology. Doctoral

Jonsson, H., A. R. Stintzing, et al. (2004). Guidelines on the Use of Urine and Faeces in Crop Production. EcoSanRes Publication Series. Stockholm, Stockholm Environment Institute. Report 2004-2

Kirchmann, H. and S. Pettersson (1995). “Human urine – Chemical composition and fertilizer use efficiency.” Fertilizer Research 40: 149-154.

Mnkeni, P. N. S., F. R. Kutu, et al. (2008). “Evaluation of human urine as a source of nutrients for selected vegetables and maize under tunnel house conditions in Eastern Cape, South Africa.” Waste management & research 26(132).

Mufwanzala, N. and O. Dikinya (2010). “Impact of Poultry Manure and its Associated Salinity on the Growth and Yield of Spinach (Spinacea oleracea) and Carrot (Daucus carota).” International journal of agriculture and biology 12(4): 489-494.

Pradhan, S. K., J. K. Holopainen, et al. (2010). “Human Urine and Wood Ash as Plant Nutrients for Red Beet (Beta vulgaris) Cultivation: Impacts on Yield Quality.” Journal of agriculture and food chemistry 58: 2034-2039.

Putnam, D. F. (1971). Composition and concentrative properties of human urine. National Aeronautics and Space Administration Contractor Report. Huntington Beach, California, McDonnell Douglas Astronautics Company – Western Division. NASA CR-1802.

Tidaker, P., B. Mattsson, et al. (2005). “Environmental impact of wheat production using human urine and mineral fertilisers – a scenario study.” Journal of Cleaner Production 15(2007): 52-62.

Vinneras, B. (2002). Possibilites for sustainable nutrient recycling by faecal separation combined with urine diversion. Department of Agricultural Engineering. Uppsala, Swedish University of Agricultural Sciences. Doctoral: 88.

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How much pooh?

Posted: October 22, 2012 in Uncategorized

Table 1 – Proposed Swedish design values for the mass of excrement (wet and dry mass produced per person per year) and concentration range of nitrogen, phosphorus and potassium excreted per person per year on dry mass bases (Kirchmann and Pettersson 1995; Höglund 2001; Vinneras 2002)

  Wet mass (kg) Dry mass (kg) Nitrogen (kg) Phosphorus (kg) Potassium (kg)
Urine 550 21 2.5-4.3 0.2-1.0 0.8-1.2
Faeces 51 11 0.5-0.7 0.13-0.5 0.1-0.5

The concentration of elements (see Table 1) in human excrement has diurnal fluctuations in individuals depending on dietary habits, hydration, perspiration, and level of physical work in the day (Heinonen-Tanski, Sjöblom et al. 2007). For example, a study in Sweden recently observed a 30% increase from the typical values of potassium in human urine probably due to the use of potassium supplement salt (Vinneras 2002). Cultures with higher meat consumption will urinate higher concentrations of nitrogen because of the increases protein content (Heinonen-Tanski, Sjöblom et al. 2007; Pradhan, Nerg et al. 2007).

These fluctuations challenge the designing process of waste management systems. Table 1 are the Swedes standard values of the mass of waste we excrete on an annual base. Nitrogen, phosphate and potassium (N-P-K, macro nutrients required by plants) by mass account for about 80%, 50%, and 60%, respectively, in domestic waste water, more than feces (Kirchmann and Pettersson 1995; Höglund 2001; Vinneras 2002; Ganrot, Dave et al. 2006; Mnkeni, Kutu et al. 2008).

 References:

Ganrot, Z., G. Dave, et al. (2006). “Recovery of N and P from human urine by freezing, struvite precipitation and adsorption to zeolite and active carbon.” Bioresource Technology 98: 3112-3121.

Heinonen-Tanski, H., A. Sjöblom, et al. (2007). “Pure human urine is a good fertilizer for cucumbers.” Bioresource Technology 98: 214-217.

Höglund, C. (2001). Evaluation of microbial health risks associated with the reuse of source-separated human urine. Department of Biotechnology. Stockholm, Royal Institute of Technology. Doctoral.

Kirchmann, H. and S. Pettersson (1995). “Human urine – Chemical composition and fertilizer use efficiency.” Fertilizer Research 40: 149-154.

Mnkeni, P. N. S., F. R. Kutu, et al. (2008). “Evaluation of human urine as a source of nutrients for selected vegetables and maize under tunnel house conditions in Eastern Cape, South Africa.” Waste management & research 26(132).

Pradhan, S., A.-M. Nerg, et al. (2007). “Use of Human Urine Fertilizer in Cultivation of cabbage (Brassica oleracea)––Impacts on Chemical, Microbial, and Flavor Quality.” Journal of agriculture and food chemistry 55: 8657-8663.

Vinneras, B. (2002). Possibilites for sustainable nutrient recycling by faecal separation combined with urine diversion. Department of Agricultural Engineering. Uppsala, Swedish University of Agricultural Sciences. Doctoral: 88.

 

Protesters sit on toilets

Posted: October 15, 2012 in Uncategorized


Developing nations aren’t the only ones with toilet issues. How often have you bought something at a cafe just to use their toilet? Public toilets are limited and are more often than not locked. And some are starting to do something about it in their area:

“Protesters bring their own toilets and drop their trousers on Adelaide beach for a sit-in to highlight the lack of public facilities in the area. Organiser and artist Andrew Baines said he wished to bring the issue to the wider community. One protesters said while they were glad of the exposure, he wish it had been in summer”

http://www.guardian.co.uk/world/video/2012/aug/20/protesters-toilets-adelaide-beach-video

Everybody poohs…

Posted: October 8, 2012 in Uncategorized

It can be hard to find a toilet… where to go when there isn’t one?

Everybody poohs – for most of you reading this blog: you have access, like me, to a toilet at home. To a waste management system that the United Nations considers adequate sanitation.*

There are over 2.6 million people around the world who don’t such access. And about 1.6 million children are dying each it because of it.

Why?

Join me on everybodypoohs.com, as once a week I’ll explore such questions through stories about where people’s pooh is going.

* Adequate sanitation is defined as: having access to improved sanitation facilities, which includes flush or pour-flush to piped-sewer system; septic tank or pit latrine; ventilated improved pit latrine (VIP); latrine with slab; and composting toilet. Unimproved sanitation facilities are flush or pour-flush to elsewhere; latrine without slab or open-pit; bucket; hanging toilet or hanging latrine; no facilities or bush or field.