• norsk
    • English
  • English 
    • norsk
    • English
  • Login
View Item 
  •   Home
  • Norges miljø- og biovitenskapelige universitet
  • Faculty of Science and Technology (RealTek)
  • Master's theses (RealTek)
  • View Item
  •   Home
  • Norges miljø- og biovitenskapelige universitet
  • Faculty of Science and Technology (RealTek)
  • Master's theses (RealTek)
  • View Item
JavaScript is disabled for your browser. Some features of this site may not work without it.

Quantitative microbial risk assessment of agricultural use of fecal matter treated with urea and ash

Fidjeland, Jørgen
Master thesis
Thumbnail
View/Open
Masteroppgave_Jorgen_Fidjeland_2010.pdf (2.587Mb)
URI
http://hdl.handle.net/11250/188680
Date
2010-12-27
Metadata
Show full item record
Collections
  • Master's theses (RealTek) [1401]
Abstract
Today about 2,6 billion people lack access to improved sanitation and over 2 billion people

use pit latrines. This results in spreading of pathogens from excreta into the environment

and drinking water sources, causing severe illnesses. In developing countries the health

impact of this is, however, overshadowed by malnutrition. Sustainable sanitation can

prevent spreading of pathogens to the environment, as well as ensure safe reuse of the

nutrients in excreta for food production in agriculture.

A planned sanitation system in Kampala, Uganda is aiming to sell fecal matter treated for

two months with urea, as a fertilizer product. Using urea, the most common mineral

fertilizer in the world, to treat fecal matter will inactivate most of the pathogens, and

increase the fertilizer value of the fertilizer product. Ash could also be used in combination

with urea to enhance the pathogen inactivation.

The objective of this research was to assess the health risk for the farmer applying the

fertilizer product, and for the food consumer eating crops grown in these fields. The

evaluation of the urea and ash treatment was conducted by using quantitative microbial risk

assessment for identifying the health risk, applying relevant data for the conditions in

Kampala.

Ascaris was identified as the main threat to human health. Assuming that the farmer is not

using protective clothing, 4 % w/w urea is needed to achieve an annual risk of Ascaris

infection less than 10-3, which is suggested to be tolerable. Health risk associated with

consuming raw carrots and spinach grown in soil amended with treated fecal matter were

acceptable if 3 % w/w urea or more was used in the treatment. Using ash in addition to urea

increased the Ascaris inactivation, but was not very favorable since water addition is needed

to maintain the moisture, extending the volumes needed during treatment.

An inactivation study of Salmonella typhimurium phage 28B in fecal matter treated with

urea and ash, showed no difference in inactivation at different pH levels. Because both

Salmonella typh. phage 28B and adenovirus are dsDNA viruses, raising the pH will probably

not affect the adenovirus inactivation either. However, a pH increase would increase the

rotavirus inactivation. More research is on their inactivation and fate in the soil is needed to

evaluate whether or not they represent a significant health risk in this context.
Publisher
Norwegian University of Life Sciences, Ås

Contact Us | Send Feedback

Privacy policy
DSpace software copyright © 2002-2019  DuraSpace

Service from  Unit
 

 

Browse

ArchiveCommunities & CollectionsBy Issue DateAuthorsTitlesSubjectsDocument TypesJournalsThis CollectionBy Issue DateAuthorsTitlesSubjectsDocument TypesJournals

My Account

Login

Statistics

View Usage Statistics

Contact Us | Send Feedback

Privacy policy
DSpace software copyright © 2002-2019  DuraSpace

Service from  Unit