Guidelines on the Safe Use of Urine and Faeces in ... - EcoSanRes

Caroline Schönning and Thor Axel Stenström
Figure 5. Open defecation is a
major route of contamination of
enteric and parasitic diseases.
Other individuals and the home
environment may be affected
through direct contact and also
by walking barefoot. In addition,
surface water sources may be
heavily impacted.
Treatment could be primary, i.e. directly in the toilet in relation to defecation, e.g. by the addition
of ash (further described below), or secondary where the material is collected from the toilet
(or left in the toilet with no further addition of faeces) and treated in a controlled way to reduce
pathogens to acceptable limits. Esrey et al. (1998) stated that a combination of safe storage and
fast destruction of the pathogens in excreta are needed in order to prevent contamination of the
environment. Barriers are exemplified in the alternate “F-diagram” (Figure 6).
Figure 6. Barriers required to prevent the transmission of disease/spread of pathogens, adapted
from Esrey et al. (1998).
Inactivation of pathogens will also occur on agricultural land after application of the excreta
as fertilizer and on crops that may have become contaminated if fertilized during growth
or from splashes from the soil during heavy rains. This inactivation with time and due to
prevailing environmental conditions can provide a barrier against exposure from handling and
consumption of crops and for humans and animals possibly entering the fertilized field. The
inactivation is dependent on ambient temperature, moisture and sunshine (that will increase
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