Transcript Slide 1

Pathogens & Contaminants
Corinne Waelti, seecon international gmbh
Pathogens & Contaminants
1
Find this presentation and more on: www.ssswm.info.
Copyright & Disclaimer
Copy it, adapt it, use it – but acknowledge the source!
Copyright
Included in the SSWM Toolbox are materials from various organisations and sources. Those materials are open source. Following the opensource concept for capacity building and non-profit use, copying and adapting is allowed provided proper acknowledgement of the source
is made (see below). The publication of these materials in the SSWM Toolbox does not alter any existing copyrights. Material published in
the SSWM Toolbox for the first time follows the same open-source concept, with all rights remaining with the original authors or producing
organisations.
To view an official copy of the the Creative Commons Attribution Works 3.0 Unported License we build upon, visit
http://creativecommons.org/licenses/by/3.0. This agreement officially states that:
You are free to:
• Share - to copy, distribute and transmit this document
• Remix - to adapt this document. We would appreciate receiving a copy of any changes that you have made to improve this
document.
Under the following conditions:
• Attribution: You must always give the original authors or publishing agencies credit for the document or picture you are using.
Disclaimer
The contents of the SSWM Toolbox reflect the opinions of the respective authors and not necessarily the official opinion of the funding or
supporting partner organisations.
Depending on the initial situations and respective local circumstances, there is no guarantee that single measures described in the toolbox
will make the local water and sanitation system more sustainable. The main aim of the SSWM Toolbox is to be a reference tool to provide
ideas for improving the local water and sanitation situation in a sustainable manner. Results depend largely on the respective situation
and the implementation and combination of the measures described. An in-depth analysis of respective advantages and disadvantages and
the suitability of the measure is necessary in every single case. We do not assume any responsibility for and make no warranty with
respect to the results that may be obtained from the use of the information provided.
Pathogens & Contaminants
Find this presentation and more on: www.ssswm.info.
Contents
1. Introduction
2. Characteristics of Pathogens and Contaminants
3. Pathogens
4. Contaminants
5. References
Pathogens & Contaminants
3
Find this presentation and more on: www.ssswm.info.
1. Introduction
The overall Problem
Substances such as pathogens (microorganisms) and contaminants
(chemicals and metals) in drinking water may harm both public health
and the environment. In developing countries, the contamination of
drinking water with pathogens is the major factor for prevalence of
diseases.
Most often, faeces infiltrating drinking water sources are responsible
for contamination with pathogens. Contaminants in drinking water may
originate from human activities and natural processes.
Pathogens & Contaminants
4
Find this presentation and more on: www.ssswm.info.
2. Characteristics of Pathogens and Contaminants
Types of Pathogens and Contaminants
Pathogens
•Bacteria
• e.g. Salmonella,
Escherichia coli,
Campylobacter
•Viruses
• e.g. Rotavirus,
Hepatitis
•Parasitic protozoa
• e.g. Giardia
•Helminths (worms)
• e.g. Trichuris
trichiura
Contaminants
• Inorganic chemicals
• e.g. nitrate, arsenic,
fluoride, chloride
• Organic chemicals
• e.g. petro-chemicals
(oil, diesel), solvents,
drugs, pesticides
• (Heavy) metals
• e.g. cadmium,
copper, lead, mercury
 Microorganisms
Pathogens & Contaminants
5
Find this presentation and more on: www.ssswm.info.
2. Characteristics of Pathogens and Contaminants
Sources of Pathogens and Contaminants
Source: BUCHANAN et al. (2010)
• Underground storage tanks
• Chemical storage
• Accidental spills of hazardous
materials
• Spreading of sewage treatment
sludge
• Septic systems
• Animal feedlots
• Storage and spreading of road
salt
• Underground pipelines or
sewers
• Use and spilling of fertilisers
and pesticides
• Landfills
• Private and abandoned wells
Source: CONSERVATION ONTARIO (2009)
Pathogens & Contaminants
6
Find this presentation and more on: www.ssswm.info.
2. Characteristics of Pathogens and Contaminants
Dispersion of Pathogens and Contaminants
Migration of contaminants in an
unconfined (left) and a confined
(right) aquifer.
Movement of insoluble
contaminants in ground water:
Oil spills (lighter than water)
accumulate on the water table
and spread horizontally.
Source: WAL (2010)
Pathogens & Contaminants
Adapted from FREEZE et al. (n.y.)
7
Find this presentation and more on: www.ssswm.info.
2. Characteristics of Pathogens and Contaminants
General Effects of Pathogens and Contaminants
Drinking water contamination:
•Poor drinking water quality
•Loss of community’s drinking
water supplies
Impacts on the environmental
system by contaminants:
• Loss of ecosystem functions
•High costs for restoration and
alternative drinking water
supplies
•Health problems
Examples for related economic
effects:
Examples for related economic
effects:
• Higher health expenses
• Less revenue by fisheries
• Restricted work force
• Less revenue from tourism
Pathogens & Contaminants
8
Find this presentation and more on: www.ssswm.info.
3. Pathogens
Transmission & Health Risks of Disease
Faecal-oral transmission routes:
• Fingers
• Flies and other insects
• Fields (agriculture)
• Food
• Fluids
Health risks:
Gastrointestinal symptoms
such as diarrhoea, vomiting
and stomach cramps
Source: HESPERIAN & UNDP (2004)
Pathogens & Contaminants
9
Find this presentation and more on: www.ssswm.info.
3. Pathogens
Probability of Causing Infections
Persistence in
the environment
Low minimal
infective doses
Little or no
human immunity
Amount and
variability of
pathogens
Long latency
periods
SHUVAL et al. (1986)
Pathogens & Contaminants
10
Find this presentation and more on: www.ssswm.info.
3. Pathogens
Probability of Causing Infections
Sanitation
system
Persistence in
the environment
Low minimal
infective doses
Little or no
human immunity
Source: http://2.bp.blogspot.com/2yIT8xt_stM/TwtB4J9sBqI/AAAAAAAACmY
/s_69HHksUA/s1600/Istanbul%20Toilet.gif
[Accessed: 05.06.2012]
Amount and
variability of
pathogens
Long latency
periods
SHUVAL et al. (1986)
Pathogens & Contaminants
11
Find this presentation and more on: www.ssswm.info.
4. Contaminants
Health Risks related to contaminated Groundwater
Possible health risks:
• Cancer
• Liver, kidney and nerve
problems
• Birth defects
• Learning disabilities in
children
Source: WALLIN (1997)
Source:
http://www.thewaterchannel.tv/tutorial/s
ection_4/6.html
Pathogens & Contaminants
12
Find this presentation and more on: www.ssswm.info.
5. References
BUCHANAN, B., DE LA CRUZ, N, MACPHERSON, J., WILLIAMSON, K. (2010): Water Wells that Last for Generations. Edmonton:
Alberta Agriculture and Rural Development. URL: http://www1.agric.gov.ab.ca/$department/deptdocs.nsf/all/wwg404
[Accessed: 05.06.2012].
CONSERVATION ONTARIO (Editor) (2009): Wellhead Protection Areas. Newmarket: Conservation Ontario. URL:
www.conservationontario.ca/source_protection/files/ODWSP%202009%20Finals/ODWSP_FAQS_wellhead_EN_2009_02_27_WEB.pdf
[Accessed: 06.06.2012].
FREEZE, R.A., ATWATER, J., LIEBSCHER, H. (n.y.): Water Stewardship . Ground Water Resources of British Colombia. Victoria: The
Province of British Columbia. URL:
http://www.env.gov.bc.ca/wsd/plan_protect_sustain/groundwater/gwbc/C05_contamination.html [Accessed: 05.06.2012].
HESPERIAN FOUNDATION (Editor); UNDP (Editor) (2004): Sanitation and Cleanliness for a Healthy Environment. Berkeley: The
Hesperian Foundation. URL: www.unwater.org/downloads/EHB_Sanitation_EN_lowres.pdf [Accessed: 05.06.2012].
SHUVAL H.I., ADIN, A., FATTAL, B., RAWITZ, E., YEKUTIEL, P. (1986): Wastewater Irrigation in Developing Countries. Health
Effects and Technical Solutions. Washington, D.C.: The World Bank. URL:
http://documents.worldbank.org/curated/en/1986/05/440564/integrated-resource-recovery-wastewater-irrigation-developingcountries-health-effects-technical-solutions [Accessed: 05.06.2012].
WAL, A. van der (2010): Understanding Groundwater & Wells in Manual Drilling. Instruction Handbook for Manual Drilling Teams
on Hydro-geology for Well Drilling, Well Installation and Well Development. Papendrecht: Practica Foundation. URL:
www.unicef.org/wash/files/04.pdf [Accessed: 06.06.2012].
WALLIN, R. (1997): Wellhead Protection: A Guide for Arizona Communities. TUCSON: Arizona Department of Environmental
Quality, Water Quality Division. URL: http://www.unicef.org/wash/files/04.pdf [Accessed: 05.06.2012].
Pathogens & Contaminants
13
“Linking up Sustainable Sanitation,
Water Management & Agriculture”
SSWM is an
initiative
supported by:
Created
by:
Pathogens & Contaminants
14