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WHO GUIDELINES F

SAFE USE OF WAST EXCRETA AND GREYWATER

VOLUME IV

EXCRETA AND GREYWATER USE IN AGRICULTURE

WHO GUIDELINES FOR THE

SAFE USE OF WASTEWATER,

EXCRETA AND GREYWATER

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EXCRETA AND GREYWATER USE IN AGRICULTURE

Volume 4

Excreta and greywater use in agriculture

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PREFACE

The United Nations General Assembly (2000) adopted the Millennium Development

Goals (MDGs) on 8 September 2000 The MDGs that see most directly related to the

safe use of excreta and greywater in agriculture are "Goal 1: Eliminate extreme

poverty and hunger” and “Goal 7: Ensure environmental sustainability.” The use of

exerein and greywater in agriculture can help communities to grow more foed and

make use of precious water and nutrient resources However, it should be done safely

‘to maximize public health gains and environmental benefits

‘To protet public health and facilitate the rational use of wastewater and excreta in

agriculture and aquaculture, in 1973, the World Health Organization (WHO)

developed guidelines for wastewater use in agriculture and aquacultute under the te

Rewse of effluents: Methods of wastewater treatment and health safeguards (WHO,

1973), After a thorough review of epidemiological studies nd other infoemation, the

guidelines were updated in 1989 as Health guidelines for the use of wastewater in

aricudtare and aquaculture (WHO, 1989) These guidelines have been very

fnffucntal, nd many countries have adopted or adapted them for thelr wastewater and

xe use practices

‘The use of exereta and greywater in agriculture is inereasingly considered a

method combining water and nutrient reeyeling, increased household food security

and improved nutition for poor househols, Recent interes in exereta and greywater

use jn agriculture has been driven by water scarcity, lack of availablity of mteiens

tnd concemns about health and envieonmental effects, Ic was necessary to update the

guidelines to take into account scientific evidence concerning pathogens, chemicals

and other factors, including changes in population characterises, changes in

Ssnitation practices, beter methods for evalbating risk, sociallequity issues and

soviocultural practices There was a particular need to conduct a review of both isk

assessment and epidemiological dats

Tn onder to better puckage the guidelines for appropriate audiences, the third

ition of the Guidelines for the safe use of wastewater, excreta and greywater is

presented in four scparate volumes: Volume I: Pliey and regulatory aspects; Volume

2) Wastenerer use in agriculture, Volume 2: Wastewater and excreta use in

‘aquaculture; and Volume 4: Bxereta ana greywater use in agrexdare

WHO waterselted guidelmes are hased on scientific consensus and best

available evidence; they are developed through broad participation, The Guidelines

forthe safe use of wasteweter excreta and greywater are designed te protect the

health of farmers (and thei families), Jocal communities and prodact consumers

‘They are meant 10 be adapted to take sto consideration national socioeuttural,

cesanomie and environmental factors, Where the Guidelines relate to technical issues

— for example, excreta and greywater (reatmen — technologies that are readily

lable and achievable (rom both technical and economic standpoints) are

explicily noted, but others are not exchided, Overly sirict standards may not be

sustainable and, paradoxically, may lead to reduced heath protection, because they

may be viewed as unachievable under local circumstances and, thus, ignored The

Guidelines rerefore sive to maximize overall public health benefits and the

beneficial use of scarce resources,

Following an expert meeting in Stockholm, Sweden, WHO published Water

‘quality: Guidelines, standards and heh — Assesment of risk and risk management

for water-relaved infections disease (Fewtrell & Bartram, 2001) This document

Dresenisa harmonized framework forthe development af guidelines and standards for

\waterclated microbial hwzards This framework involves the assessment of health

Sacir€ó bạn quy

risks prior to the setting of health targets, defining basic cantrol approaches and

evaluating the impact of these combined approsches on public health staus The

Framework is exible and allows counties to take into consideration health vsks that

may result from microbial exposumes through drinking-water or contact with

recreational or occupational water It is important that health sks from the use of

exereta and greywater in agriculture be put into the context of the overall burden of

disease within a given population

‘This volume of the Guidelines for the safe use of wastewater, excreta and

greywater provides information ơn the assessment and management of risks

sssovated with mierobial hazards 1 explains requirements to promote the safe use of

fexereta and greywater in agriculture, ineluding minimum procedures and specific

health-ased targets, and how those requirements are intended 10 be used This

volume also describes the approaches used in deriving the guidelines, including

health-based targets, and includes a substuntive revision of approaches to ensuring

microbial safety

This edition ofthe Guidelines supersedes previous editions (1973 and 1989) The

Guidelines are recognized as representing the position of the United Nations system

fon issues of wastewater, excreta and greywater use and health by “UN-Water.” the

‘oordinating body ofthe 24 United Nations agencies and programmes concerned with

‘water issues This edition ofthe Guidelines further develops concepts, approaches and

information n previous editions and ineludes addtional information on

+ the context of the overall waterborne disease burden in a population and how

the use of excreta and greywater in aoriculture may contribute to that burden;

+ the Stockholm Framework for development of water-elated guidelines and the

setting of healdh-based arzets:

risk analysis:

+ risk management strategies, including quantification of different health

protection measures;

+ guideline implementation strategies

‘The revised Guidetines will be useful tall dhose concerned with issues eating 10

the safe use of wastewater, evereta and greywater, public health and water and waste

‘management, including environmental and public health scientists, educators,

researchers, engineers, policy-makers and whose responsible for develeping standards

and regulations,

bạn

ACKNOWLEDGEMENTS

‘The World Heath Organization (WHO) wisest expres its aprasation oil hose

whose effons mae posible the production of the Guidelines for the safe ase of

Twstewater exeeta and greywater Volume 4: Excreva and greywoter use in

agriculture, in paricular Dr Jamie Bartam (Coordinator, Water, Sanitation and

Health, WHO Geneta) Mr Richard Carr (Technical Officer, Wate, Sanitation and

Heath, WHO, Geneva) and De Thor Axel Stesrdm_ (Head of Waer mở

Environmental’ Microbiology, Swedish Insitute for Infectious Disease Control

Stockholm), sho eoordinated the development ofthis vokume ‘An intsmatonal group of experts provided mateal and paricpated ia the

development and review of Vollme 4 of the Gaideliney for the safe ase of

‘wastewer.erereta and grevwuter Many individuals contributed to cach chapter,

diretly and dough awocited activites The conto of the following to the

development of these Guidelines ae appreciate:

‘Mohammad Abed Aziz Al-Rasheed, Ministry of Health, Amman, Jordan

Sager Al Salem, WHO Regional Centre for Environmental Health Activities,

‘Amman, Jordan

John Anderson, New South Wales Department of Public Works & Services,

Syeiey, Australia

‘Andecas Aagelakis, National Foundation for Agricultural Research, Institute of

Traklo, Iaklio, Greece

‘Takashi Asano, University of California at Davis, Davis, California, USA

[Nichohis Ashbol,* University of New South Wales, Sydney, Ausraia

Lorimer Mark Austin,* Couneit for Seientifie and Industrial Research, Pretoria,

South Africa

Ali Akbar Azimi, University of Tehran, Tehran, ran

Javed Aziz, University of Engineering & Technology, Lahore, Pakistan

‘Akiga Bahri, National Research Institute for Agricultural Engineering, Water, and

Forestry, Ariana, Tunisia

‘Mohamed Đazza, Food and Agriculture Organization of the United Nations,

Cairo, Eaypt

Ursula Blumenthal," London School of Hygiene and Tropieal Medisine, London,

United Kingdom

Jean Bontous, Unversity of Monipellet, Montpeliee, France

[Laurent Bontous, European Commission, Brussels, Beajurm

[Robert Bos, WHO, Geneva, Switaeland

Patrik Brocken,* Deutsche Gesellschaft flr Technische Zusammenarbeit (GTZ),

Eschborn, Germany

FFrangois Brissaud, University of Montpllier I, Montpellier, France

Stephanie Bucchler, International Water Management Institut, Pantarchera,

‘Anden Pradesh Inia

Paulina Cervantes-Oliver, French Environmental Health Agenes, Maisons Afr

France

Andrew Chang, University of California at Riverside, Riverside, Califo, USA,

Guelladio Cissé, Swiss Cente for Scientific Research, Abidin, Cote d'Isoie

Joseph Cotravo, J Cotruve & Associates, Washington, DC, USA

‘Brian Crathorne, RWE Thames Water, Reading, United Kingdom

David Cunliffe, Environmental Health Service, Adelaide, Australia

‘Anders Dalsgaard, Royal Veterinary and Agricultural University, Frederiksberg,

Denmark

“Anas (ines he preparation of sata aia

‘Gayziri Devi, lternational Water Management Institute, Andhra Pradesh, nda Ju) Olor Dranger.* Universi’ of Linkdping Sweden

ay’ Drechsel International Water Management Institute, Agora, Ghana

[Bruce Durham, Veolia Water Systems, Derbyshire, United Kingdom

Peter Edwards, Asian Insitute of Technology, Klong Luang, Thailand

Dirk Engels, WHO, Geneva, Switerland

Badri Fatal The Nebeew University Jrusilem, leusalem, Isral

John Farwell, independent consultant, Flackwell Heath, United Kingdom

Pinchas Fine, Insinte of Soil, Water and Environmental Sciences, Bet-Dagan, Israel

Jay Fleisher, Nova Southeastern University, Fort Lauderdale, Florida, USA, Yanfen Fu, National Centre for Rural Water Supply Technical Guidance, Being People's Republic af China

‘Yaya Ganou, Ministry of Health, Ouagadougou, Burkina Faso

Alan Godley, United Uli Water, Warrington, United Kingdom

Maria tsabel Gonzalez Gonzalez, National Institue of Hygiene, Epidemiol

Microbiology Havana, Cuba

‘Cagatay Guler, Hacedepe University, Ankara, Turkey

(Gary Hartz, Director, Indian Health Service, Rockville, Maryland, USA

Paul Heaton, Power and Water Corporation, Daewin, Northern Territory, Australia Ivano Hespanto, University of Sa0 Paolo, Sao Paolo, Brazil

oss Hae, WHO Geneva, Switzerland

Peter Jenssen.* University of Life Sciences, Aas, Norway

Banca Jiménee, National Autonomous University of Mexico, Mexico City, Mexico

Jean-Frangois Junger, European Commission, Brussels, Belgium

loannis K: Kalavrousiotis, University of loannina, Agrnio, Greece

Peter Kolsky, World Bank, Washington, DC, USA

Doulaye Kong* Swiss Federal Instimte for Environmental Science and

“Technology (EAWAG) / Department of Water and Sanitation ia Developing Countries (SANDEC), Duebenderf, Switzerland

‘Sasha Koo-Oshima, Food and Agriculture Organization of the United Nations, Rome, italy

Eliseth Kvamstnim.* Verna Ecology Tne, Stocksolm, Sweden|

“Ale Sipisia Lakati, Department of Environmental Health, Nairobi, Kenya Valentina Lazarova, ONDEO Serviess, Le Peeg, France

Pascal Magoarou, European Commission, Brussels, Belgium

Duncan Mara,* University of Leeds, Leeds, United Kingdom

‘Gerardo Mogel, Deparment of Health, Manila, Philippines

Gerald Moy, WHO, Geneva, Switzerland

‘Rafael Majeviego, Teehnical University of Catalonia, Barcelona, Spain

Gonstuntino Nurizzo,Polteenio di Milano, Mila, aly

Gideon Oron, Ben-Gution University ofthe Neges, Kiryat Sde-Boker, tse Mohamed Ouahil, Ministry of Health and Population, Algiers, Alveria

‘Albert Page, University of Californie at Riverside, Riverside, California, USA, (Gensing Pan, Nanjing Agricultural University, Nanjing, People's Republic of China

Nikolaos Paranychianakis, National Foundation for Agricultural Research, Instinte of take, ralio, Greece

‘Martin Parkes, Notth China ‘College of Water Conservancy and Hydropower, Zhengzhou, Henan, People's Republic of China

‘Susan Petterson,* University of New South Wales, Sydney, Australia

Liga Raschid-Sally, Intersivonal Water Management Instfiue, Accra, Ghana Anna Richen-Stnzing,* Vera Ecology Ine, Stockhalim, Sweden

Kerstin Riske, Insite for Medicine, Microbiology’ and Hygiene, Dresden, Germany

Lorenzo Savioli, WHO, Geneva, Switzerland

Jorgen Sehlundt, WHO, Geneva, Swiverland

Caroline Schonning.*” Swedish Instinte for Infections Disease Control,

‘Stockholm, Sweden

Janine Schwvartzbrod, Univesity of Naney, Naney, France

Louis Schwartzbrod, University of Nanoy, Naney, France

Natalia Shapicova, Ministry of Health, Tashkent, Uzbekistan

Hille! Shuval, The Hobrew University of Jerusalem, Jerusalem, Israel

Martin Strauss," Swiss Federal Institue for Environmental Science and

“Technology (EAWAG) / Department of Water and Sanitation in Developing, Countries (SANDEC), Ducbendorf, Switzertand

Ted Thairs, BUREAU Working Group on Wastewater Reuse (former Seoretary}, Herefordshire, United Kingdom Terrence Thompson, WHO Regional Office for the Western Pacific, Manila, Philippines

“Sanh Tibatema, National Water & Sewerage Comporaton, Kampala, Uganda Andrea Tilehe, European Commission, Brussels, Belgium

Musaiko P, Tole, Kenyatta University, Nairobi, Kenya

Francisco Torrella, University of Marcia, Murcia, Spain

Hajime Toyofoku, WHO, Geneva, Switzerland

‘Wim van der Hoek, independent consultant, Landsmeer, The Netherlands

Johan Verink, ICY Waste Water & Energy Hanover, Germany

“Marcos von Sperling, Federal University of Minas Gerais, Belo Horizonte, Brazil (Christine Weme,* Deutsche Gesellschaft fir Technische Zusammenarbeit (G12), Eschbom, Germany

‘Steve White, RWE Thames Water, Reading, United Kingdom

Thanks are also due to Marla Sheffer for editing the comple text of the Guidelines, Windy Prohom and Colette Desigaud for their assistance in project

‘adnisteation and Peter Gosling, who aeted as the rapporte forthe Final Review

“Meeting forthe Finalization of the Third Edition of the WHO Guidelines for the Sale Use of Wastewater, Exereta and Greywater in Geneva,

“The preparation of these Guidelines would not have been possible without the generous support ofthe United Kingdom Department for International Development, the Swedish Intemational Development Cooperation Ageney (Sida) through the Stockholm Environment Institute, the Norwegian Ministry of Foreign Affairs, the Deutsche Gesellschaft fr Technische Zusammenarbeit (GTZ) and the Dutch Ministry

of Foreign Affairs (DGIS) through WASTE (advisors on urban environment and development)

XECUTIVE SUMMARY

‘This volume of the World Health Organization's (WHO) Guidelines forthe safe use

of wastewater, excreta and greywater describes the present state of knowledge fegarding the impact of excreta and greywater use in agriculture on the health of

product consumers, workers and their families and local communities Heath hazards

ae identified for each group at risk, and appropriate health protetion measures to

mitigate the risks ae discussed

‘The primary sim ofthe Guidelines iso maximize public health protection and the

beneficial use of important resources, The purpose of this volume is to ensure that the

use of excreta and greywater in agriculture is made as safe a5 possible so that the

nutritional and household food security benefits can be shared widely in affected

communities, Thus, the adverse health impacts of exereta and greywater use in

agriculture should be carefully weighed ayainst the benefits 10 health and the

snvironment associated with these practices, Yet this isnot a mater of simple trads-

ofl Wherever excreta and greywater use contributes sigificamly ta food security

and autritonal itu, the point s fo identity associated hazards, define the risks they

represent to vulnerable groups and design measures aimed at reducing these risks

‘This volume of the Guidelines is intended to be used as the basis for the

evelopment of intemarional and national approaches Gneluding standards and

in agriculture, as well as providing a framework for national and Toval

ng

‘The information provided is applicable (o the intentional use of exereta and

greywater in agriculture, butt should also be relevant to their unintentional use

"The Guidelines provide an integrated preventive management framework for

salety applied from dhe point of household excreta and greywater generation 10 the

consumption of products grown with rested excreta applied a5 fertilizers or treated

fexywater used for irigation purposes, They describe ressonable minimmam

requirements of good practice to protect the heath of the poople using tested excreta

or greywater or consuming products grown with these for fertilization er irgation

purposes and provide information that is then used to derive health-based targets,

Neither the minimum good practices nor the health-hased targets are mandatory

Fimits The prefered approaches adopted by national or local authorities towards

‘of the Gutdlins, including healt-hased targets, may vary depending

fon local social, cultural, environmental and economic conditions, as well as

knowledge of routes of exposure, the nature and severity of hazards and the

effectiveness of health protection measures available

‘The revised Guidelines forthe safe use uf wastewoter, excreta and greywater wil

be useful to all those concermed with issues relating tothe safe use of wastewater,

fexereta and greywater, public heal, water resources development and wastewater

‘management The target audience may include public health, agricultural and

environmental scletsts, agriculture protessionals, educators, researchers, engineers,

policy-makers and those responsible for developing standards and regulations

Introduction

Traditional waterborne sewerage will continue 40 dominate sanitation for the

foresceahle faure Since only a action of existing wastewater treatment plants inthe

World are optimally reducing levels of pathogenic microorganisins and since a

majority of people living in both rural and urban areas will not be connected 10

convalized wastewater Weatment system, aliemative sanitation approaches need 10 be

‘developed in paral

The United Nations General Assembly adopted the Millennium Development Goals (MDGs) on 8 September 2000 (United Nations General Assembly, 2000) The MDGs most dircely related 10 the use of excret and greywater in ageeultre are Goal 1: Eliminate extreme poverty and hunger” and “Goal 7: Ensure environmental sastinability.” The sanitation target in Goal Tis to halve, by 2015, the proportion af people without aecess to adequate sanitation Houschold- or community-centred Source separation 8 one of the allerative approaches thal is rapidly expanding in

‘order to moot this target, It also helps to prevent environmental degradation and to promote sustainable reeyeling ofthe existing plant nutrients fn human excreta for food production

‘The principal forees driving uhe increase in use of excreta and greywater in agriculture are:

‘+ increasing water scacity and stress, and degradation of freshwater resources

‘resulting from the improper disposal of wastewater, excrea and greywater:

‘+ population increase and related increased demand for fod and fre;

+ a growing recognition of the resource value of excreta and the nutrients it + - the MDGs, especialy the goals for ensoring environmental sustainability and climinating poverty and hunger

Growing competition between apriculturl and urban areas for high-quality {reshsater supplies, particularly in arid, semi-arid and densely populated regions, ill Jncrease the pressure on this inereasingly scarce resource Most population growth is expected to occur in urban and perurban areas in developing countries (United Nations Population Division, 2002) Population growch increases both the demand for fresh water and the amount of wastes that aze discharged into the environment, thus leading to more pollution of clean water sources, Household-cented source separation and the safe se of exercta and greywater in agriculture will help to alleviate these pressures and help communities to grow more food and conserve precious water and rutrient resources The additional advantages of nutrient use from excreta as fertilizers aretha this “product” is less contaminated with indusirial chemicals Uhan| when wastewater is used and that it saves water For other uses

This velume focuses mainly on small-scale applications It is applicable to both Industrialized and developing countries

‘The Stockholm Framework

The Stockholm Framework is aa integrated appeoach tht combines rsk assessment and risk management to contol water-related diseases This provides « harmenized framework for the development of health-based guidelines and standards in tems of

\water-and santaion-related microbial hazards The Stockholm Framework involves the assessment of health risks prior to the setting of health-based targets and the

‘development of guidaline values, defining basie contol approaches and evaluating the

‘impact of these combined approaches on public health The Stockholm Framework provides the conceptual framework for these Guidelines and other WHO water-related suidelines

Assessment of health risk

Three types of evaluations are used to assess risk: microbial analysis, epidemiological studies and quantitative microbial risk assessment (MRA) Human faeces contin a

Flume 4 Bxcreta and greveuter nee ov agricul

variety of different pathogens reflecting the prevalence of infetion inthe population:

in contrast, only a few pathogenic species may be exereted in urine The risks associated with both reuse of urine as a fertilizer and the use of greywater for invigation purposes ate related 10 cross-contamination by focal - matter Epidemiological data For the assessment of risk thrauzh treated faeces, feal sludge, rine of greywater are searee ad unreliable, while ample evidence exists related t0 untreated faceal mater In addition, microbial analyses are partly unreliable in the prediction of risk due to a more rapid diel of indicator organisms such as Escherichia collin uring, leading 10 an underestimation of the risk of pathogen transmission The epposite may occur in greywater where a growth of the indicator bacteria on easily degradable organi substances may lad to an overestimation ofthe risks, Based on the above limitations, QMIRA is the main approach taken, due tthe range of organisms with common transmission characteristics and thet prevalence in the population Factors accounted for include:

+ major transmission routes;

1+ relative efficiency of diferent reatment barriers:

4 risk management measures,

Health-based targets

Healh-base targets define a tecel oF heath prveetion hati lovato eae za

‘Atealihbaped tage can be based on a standard metric of discus, such as day adjusted fe year of DALY (ie 10* DALY), ot itean be based on ab appropriate

‘ath outcome, auch 2b the prevention of exposure to phogsns in excreta and greywater anytime between ther generation atthe hooschol level and thet we in 2dellue, To achieve a healhcbasod trast, heallh protection meaics are developed Usually 9 healh-based target ean be achieved hy combining health volstlon measares aged at diffrent scp the press “The ealthchased targets may be acicved trough afferent weatment barriers of heath preston measures The barr relate to erfcation monitoring, mainly in langesels sydems a lsat in Table | or excreta and greywater Veriiation thon ong inapplicable owing

"The health-bse targets may alo relat to operational monitoring, such as soage jas an on-site treatment ease or further treatment offsite after collection, This 5 xempliid for aes fom small-scale syste in Table For collected urine, storage entra apply that are derived mainly from compiled Fisk assessment stdin, The formation oad Ras been converted (0 apeatiosl fudelnes to mit thers wo aleve below 10" DALY, also accounting Fr aia festhprscetion measures The operational guidelines are based source separation

ot urine (Table 3) In case of heavy faealetoss-contaminaton, the suggested orage times may’ be lengthened If urine is used as a feilizr of crops for hoxsehold consumption only, it can be used dccly witout storage The DAaiheed of houschold disease irasmissionateutabe to the lak of hygiene is much higher than that of wansmission hough wine applied as elzer

Relsediecl0'vhey

le eo or dp

“Tabe2 Recommendations or storage este of dey excel and aceatsndge bear wea

‘Storage: ambient 15-2 yer Wil elimina acer pthosns repowth OF Ecoand|

Some vitoene ove ay pr no mabe

(echuray sual of erin pia (10 3%) 0F expt ict of dacs eas wil ocr win

Health protection measures

A variety of health protection measures can be used 0 reduce health risks for local communities, workers and their Families and for the consumes of the fnilized or irrigated products

Havards associated with the consumption of excreta-ferilized produets include

‘excretatelated pathogens The risk from infectious diseases is signfieanty reduced if foods are eaten afler proper handling and adequate cooking The following health protection measutes have an impact on produet consumers

1+ cxoreta and ereywater treatment crop restestions

‘+ waste application and withholding prinds between fentlization and harvest allow die-off of remaining pathogens,

+ hygienic food handing a Food preparation praties

+ health and hygiene promotion;

+ produce washing, disinfection and cooking,

sess, bu íc ni novnali eogfi2e á ease fay weetions of encom, “

‘consumed hy dividuals exer than members of the household fran whom ihe ine was collected,

2 Notgmolinds oe prouction a oder

«Far fod crops ht re onset esommended ta he rine He appli Teli harveting and Bin i mevpnuel tro he pound ie sie prs ow above the est one mah

ih arying walling pads Per mebdhlly ieu) For all types of tested excreta, additonal safety measures apply, These include, for example, a recommended withholding time of one month between the moment of application of the treated excreta asa fertilizer and the lime of erp harvest (Figure 1), [Based on QMRA, this time period has been shown to result in a probability of {infection well below 10 which i within the range ofa 10"° DALY

vel

Workers and their families may’ be exposed to exereta- related and vector-home pathogens (in certain locations) through excreta and greywater use activities Exereta and greywater treatment is a measure to prevent diseases associated with excreta and freywaler hut will nt directly impact yweior-hore diseaces, Other health protection

‘measutes For workers and thei Families include

use of personal protective equipment:

aoeess to safe drinking-water and sanitation files at farms

health and hygiene promotion;

disease vector and intermediate host contol,

reduced vector contact

Local communities ate at risk fom the same hazards as workers IF they do not have access to safe drinking-water, they may use contaminated ieigation water for sinking or for domestic purposes Children may also play or sim in the contaminated water Similarly, af the aetvides result in inereasod vector breeding then vector-bome diseases ean affect loc communities, even if they do not have iret access to the Fieks, To reduce health hazards, the following health protection

‘measures for local communities may be used

exerota and greywater wealments

limited contact during handling and controled access o elds;

access to sae drinking-water and sanitation Tails in Focal commvnites health and hygiene promotion;

disease vector and intermediate host contol,

redueed vector contact

Monitoring and system assessment

Monitoring has three different purposes: validation, or proving that the system is capable of mecting its design requirements; operational monitoring which provides information regarding the functioning of individual components of the heaHh protection measures; and verification, which usually takes place atthe end of the process o ensure thatthe system is achieving the specified target

The three functions of monitoring are each used fr different purposes a diferent times, Validation is performed when a new system is developed or when new processes are added and is used to test or prove tha the system is capable of meeting the spesified targets Operational monitoring is sed on routine basis to indicate that processes are working as expected Monitoring of this type relies on simple

‘measurements shat ean be read quickly so that decisions ean he made in time t0 remedy a problem Verification is used to show that the end product (eg treated xerels oF EreyWwater erops) meets treatment targets and ultimately the healh-based targets Information from verifieation monitoring is collected periodically and thuc would arrive too late fo allow managers to make devsions to prevent a hazard break: Chrough However, verification monitoring in larger systems can indieate trends over time (eg if the elfciency ofa specific process was improving oe decreasing}

"The most effective means of consistently ensuing safety inthe agricultural use of cexerets and greywater i through the use of» comprehensive risk assessment and risk management approach that encompasses all steps i the process from waste

‘generation to treatment, use of exereta as fertilizers or use of greywater for irigation purposes and product use or consumption Three components of this approach are

Flume 4: Bxerota and greveutor ne »

Important for achieving the health-based targets: system assessment, identifying control measures and methods for monitoring them and developing @ management plan

Sociocultural aspects

Muman behavioural pattems anc a key determining factor in the transmission of exerdaxebted discates The social feasibility of changing cerain behavioural patiems in order to introduce exereta or greywater use schemes or 1 reduce disease transmission in existing schemes needs to be asessed on an individual project basi Cultural beliefs and public perceptions of excreta and greywater use Vary so Widely in different pans of the world that one eannot assume that any of the local practices that hhave evolve in relation to such use can be readily transferred elsewhere Even wien projects are techneally wel planned and all of the relevant health protection measures have heen inchided, they can fail if cultural beliefs and public perceptions have not been adequately accounted for

Environmental aspects

Excreta are an important source of nutrients for many farmers The direct use of exereis and greywater on arable land tends to minimize the envizormenta impact in both the local and global context Reuse of excreta on arable land sevures valuable Ferilizers for crop jwodystion and limits the negative impact on water bodies The environmental impact of diferent sanitation systems can be measured in terms ofthe conservation and use of natural resources, discharges to water bodies, sir emissions and the impacts on sols In this type of assessment, source separation and houshold

‘entre use systems frequently score more favourably than conventional systems

‘Application of exereta and greywater to agricultural land will reduse the đứt Impacts on water bodies As for any type of ferilizer, however, the nutrients may percolate ilo the groundwater if applied in excess or used into the surface water aller excessive rainfall This impact will always be less than that ofthe direct use of

‘water hodies asthe primaty recipient of exereta and greywater, Surtace water bodies are affected by agricultural drainage and runofT Impacts depend on the type of water body (rivers, agricultural channels, lakes oF dams) and their use, as sell a¢ the hydraulic retention time andthe function it performs wihin the ecosystem,

PPhesphoru is an essential element for plant growth, and external phosphorus from mined phosphate is usually supplied in agriculture in order to increase plant productivity World supplies of accessible mined phosphate are diminishing

‘Approximately 25% of the mined phosphorus ends up it aquatic environments or buried in landfills or other sinks This discharge into aguatie envizonments is damaging, as it causes eteephication of water bodies, Urine alone eontans more that 50% of the phosphorus exerted by humans, Thus, th diversion and use of urine in agriculture can ald erop production and reduce the costs of and need for advanced

‘wastewater reament praceses to remove phosphorus rom the treated eluents,

Economic and financial considerations

Economic factors are especially important when the viability of a new projet is appraised, but even an economically wordywhile project can fail without care, financial planning

Economic analysis and financial considerations are crucial for encouraging the safe use of exereta Economic analysis secks 10 establish the feasibility of a project and enables comparisons between different options The cost transfers oer sectors

(eg the health and environmental impacts on downstream communities) also need 10

be included ina cost analysis, This canbe facilitated by the use of mulipe-ebjective Aecision-making processes

Financial planning considers how the project isto be paid for In establishing the financial feasibility ofa project, i s important to determine the sourees of revenues and clarify who will pay for what The ability to profitably sell products fertilized with excreta or irigated with yreywater also needs analysis

In developing «national policy framewark to facilitate the safe use of excreta as ferilter, i is important to define the objectives of the policy, assess the current policy environment and develop a national approach National approaches for Adequate sanitation based onthe WHO Guidelines will provect public health eptimally

‘shen they ae integrated into comprehensive public health programmes that include other sanitary measures, such as health and hygiene promotion and improving access (o sae drinkingovatr

"National approaches need to he adapted to the local sociocultural, environmental and economic circumstances, but they should be aimed at progressive improvement of public health Interventions that address the greatest local health threats first should be giXen the highest priory As resources and new data become available, addtional halt protection measures can be intrxluced

Planning and implementation periode

Planning and implementation of programmes forthe agricultural use of excreta and greywater require comprehensive, progressive and incremental approach that Fesponds to the greatest health peortics first This integrated approach should be based oman assessment ofthe cent sanitary situation and should take into account the local aspects related to ater supply and solid waste management A sound basis for such an approach can be found in the Bellagio Principles, which prescribe that akeholders be provided with the relevant information, enabling them lo make informed choices.” Thus, « wider range of decision-making and evaluation criteria {or sanitation serviees can be applied

In addition, projet planning requires consideration of several different issues identified through the involvement of sakeholders applying participatory methods tnd considering treatment, crop restriction, taste application, homan exposure control, cost, technical aspects, support services and taining bath for risk reduction tnd for maximizing the benefits from an individual as well asa community point of

1 INTRODUCTION

“greywater prescos information on the healt risks associated with pathogens

{ha oscur in human exereta and greywater when wsed in agriculture 1 also

presents heath protection measures, rclodin technical barriers and best practices to

‘minimize these risks, The Guidelines ae based on the development and use of health

based targets Health-based targets establish a goal of attaining a certain level of

health protection in an exposed population This volume furthermore inelades

evidence on the fertilizing value of treated excreta, relates their use To sstainablity

triteria, outlines planning, prevention and implementation strategies and puts th

safe handling in legal, nstitional and esonomie framework Any possible adverse

pacts wll be weighed agains the health and environmental benefits of recirculating

hutriens to arable land Positive health impacts, such as the contribution to better

rnotition and the impact on household food security, especially forthe poor, need to

be considered in his context

"The poor beat the heaviest burden of diseases transmited through tiecal-ral

pathways, which include comaminated water and improper excreta disposal

“Therefore, the postive health outcome of these Guidelines is potentially pretest for

the poorest members of society reflecting «social equity dimension, & significant

amount of human excreta is used in subsistence agriculture Although the mai focis

ofthe Guidelines ison small-scale systems ther scone i not lite to these

This volume of the Guidelines for the safe use of wastewater, excreta and

_greynater istractred as one in igure 11

T: volume of the Guidelines for the safe use of wastewater, excreta and

Smt of Volume ofthe Guielins fr he fe wef steed excreta an grew

\ Sits bat quyền

‘Chapter 1 presents the objectives and introduces some conceptual issues it also escres the target audience, the driving forees behind excreta and wreywater use, the resource value and the Milleniuin Development Goals (MDGs) Chapter 2 provides

an overview of the Stockholin Framework Chapter 3 provides the epidemiological, Imicrobiologieal and risk assessment bases for the Guidelines, Chapters 4 and $ present health-based targets and health protection measures, including technical

‘components, cop restritions agricultural mead, human exposure control, hyiene education and health care aspects, tile chapter 6 provide practical guidance on

‘monitoring and system assessment, Chapters 7, 8 and 9 provide backeround information on sociocultural, environment and economic and financial aspects The policy, institutional and legal frameworks are covered in chapter 10, and planning and Implementation pocedures are presented in chapter I

1.1 Objectives and general considerations

The primary objective ofthese Guidelines isto protect the health of individuals and benefit the health status of communities by the sae use of excreta and greywater in a range of agricultural applications The Guidlines consider the positive health outcomes of this use (such as its contribution to better nutrition and food security), without presenting these as trade-ofls

“To this end, the Guidelines describe revommended reasonable minimum safe practice requirements and system performance 10 protect the healh of the people lsing excreta and greywater, local communities and the consumers of products grown,

‘sith them, The Guidelines support the development and implementation of risk

‘management svateyies, The roquted level of health protetion can he achieved by tưởng a combination of manazement approaches (e.g handling and crop restetion, hhuman exposure control) and quality targets to arive atthe specified health vatcome Thus, the guidance provided concerns beth good handling practices and quality speculations and may inelode:

+ level ofmanagernents

+a concentration ot a constituent that doesnot represent significant sk 1 dhe health of members of important user roups;,

‘+a onltion under which such exposures are unlikely to occur; oF

+a combination ofthe fst vo,

‘The Guidelines relate to an integrated risk management framework (see the Stockholm Framework in chapter 2) applied ftom the point of generation to consumption of products grown with exereta or greywater The approach followed in

‘these Guidelines i tended to lead to national standards and regulations that can be realy implemented and enforced and are protective of public health, Iti essential that each country review its needs and capacities in developing & regulatory framework In order to define national standards and procedures, itis necessary 10 consider the Guidelines in the context of local environmental, social, economic and cultural conditions (WHO, 2004) Suecessfl implementation of the Guidelines ill equire a broad-based policy framework that includes positive and negative incentives

te alter behaviour and monitor and improve situations, This will require significant efforts in interseetoral coordination and cooperation at national and local levels and the development of suitable skills and expertise

In some situations, it wil note possible to fully implement the Guidelines at

‘once The Guidelines allow ineremental implementation, The greatest threats to heath should be given the highest priority and addressed frst Overtime, it should be

Volume 4 Bxoroa and

‘sansparent and accountable politcal decision-making proces

1.2 Target audience and definitions

These Guidelines are targeted at decision-makers and regulators in World Health Organization (WHO) Member States who are responsible for scting the framework

to, planning and implementing activites in santation-olted areas Its hoped that these Guidelines will also be useful all those with a stake or interest inthe safe use

of excreta and greywater, public health and water and waste management, including environmental and public healt scientists, educators, farmers, researchers, engineet, community planners, polieymakers and reulatrs

The health hazards linked to the agricultural use of exereta and greywater vary with the distribution of pathogens, the local transmission and exposure pathways and the capacity of health sevices to deal with them, The pathways are closely related to handling practices in the chain fom the producer to the wse, including ingestion af sontaminated food products, The responsibility for minimizing health risks Fes with the direct users of exerota and greywater withthe planners and managers of systems where excreta and greywater are applied and withthe local and national regulatory authorities that set standards for norms and procedures NongovemtmenHl organizations and special interest groups also have an important role 10 play in helping local commamitis to maximize the reuse of valuable resources while ensuring that healt risks are reduced toa minimur

In the comext ofthese Guidelines, “excreta” refers to acces and urine, but aso 10 exeretaderived products, such as faecal sludge and septge (for definitions of terms used in the Guidelines, sce Annex 1) Sludge derived from the treatment of municipal

‘industrial wastewater isnot included in these guidelines The ma focus of these Guidelines is the prevention of infectious disease wansmission, and health isstes associated with exposure to chemicals are discussed only in broad terms,

“Greywater” is defined as wastewater from the kitchen, bath and lundy, excluding wastewater from wilets, and therefore generally contains lower concentrations of excreta, except in specific situations as a result of infant eare oF

‘where anal cleansing water is combined withthe greywater Greywater is used mainly {or irrigation, but health issues are also associated withthe use of greywater for ether purposes, such as iletMushing, service water oF groundwater infiltration,

‘rvitoamentl, sociocultural and ezonomie condition atthe national evel below

In some cases, countries may choose to develop different stindards for products

3

consumed locally and for products destined for export, Wherever lower national standards are set, based ona locally adopted level of tolerable risk {sce chapter 2 fr & further discussion of tolrable risk, the incidence of diarthoeal or other diseases reeds to be accounted for

1.3.2 Food exports

The Guidelines ean be adapted based on lacal conditions except in elation to the tiles that govern intemational trade in food, which have been agreed during the Uruguay Round of Motilatral Trade Negotiations and apply 0 all members of the World Trade Organization (WTO), With regard to food safety, rules are set out inthe Agreement on the Application of Sanitay and Phytosanitary Measures According to this, WTO members have the right to take legitimate measites to proce the life and health of their populations from hazards in food, provided thatthe measures are not Lenjstifably restrictive of trade (WHO, 1999), There are documented eases where the import of contaminated vegetables has led to disease outbreaks in eeipiem countries Pathogens ean be iniroduced ino communities lacking wmmuniy resulting in important disease outbreaks (Frost el 1995: Kapperud etal, 1995) Guidslnes for the international trade of excreta-fertlized and wastewater imignted food products therefore need to be based on sound scientific sk management principles

‘WHO Guidelines for the safe use of exereta and greywater in agriculture are hased

fn a risk analysis approach that is recognized a8 the fundamental methodetosy

‘underlying the development of food safety’ standards that both proside adequate health protection and faite trade in food, Adherence to the WHO Guidelines will help to tnsure the intematonal trade of safe Food products in the case af export of exeretae ferilized or greysater-ierigated Food products

1.4 Factors that affect sustainability in sanitation

Sustainable development, as defined in the Report of the World Commission on Environment anid Development (WCED, 1987) is development that “mets the needs

Of the present generation without compromising the ability of future generations to rect their own needs” From both a sustainability and a public health perspective, increasing access to adequate sanitation and promoting the adoption by individuals and communities of key hygienic behaviours are ist priorities

Within the scope of the Guidelines for the safe use of wastewater, eccreta and _greynare, sustainability ean be describ asthe ability to an and manage the use of exerota and greywater in agrieulture as important resoores in sus a way'that human health is not compromised, nutrients are recycled for food production and negative Jmpacts on water resources ofthe envionment are avoided Sustainability nesdk ro be defined in relation tothe interaction of users, organizational stcture and techoology,

‘with a range of important criteria: health and hygiene, environmental and resource use, economy, socigeultual aspects and use and technology function These aspects should be addressed with appropriate policies and within a conducive legal and regulatory framework they are covered in different parts of the Guidelines

1-4} Health and hygiene

‘The process of reducing disease hurdens through improved sanitation is associated with the determinants of sustainability and is closely related to hygiene, behavioural change and proper access to and use of Water and sanitation facilis, Focusing on just the provision of sanitation hardware wil not result in sustainable change and will therefore not have lasting impact onthe health staus of communities Health aspects

of exereta and greywater use ate Further dealt with in chapters 3 and 8,

4

Flume 4 Bxcreta and greveuter nee ov agricul

1.4.2 Environment and resource wse

Minimizing the negative impacts of exereta and greywater on surface water and

groundwater and making more eficient use of the nutrient resourees that they contain

for crop and energy production will diectly coniibute t environmental

sustainability The environment will most importantly benefit from the teatment snd

safe use of excreta and greywater in terms of:

eyeing of water and nutient resources:

reduction of pressure on freshwater resourees;

reduction of dawnstream pollution from the discharge of wastes

reduetion of potential environmental impacts from various chemicals (among

thers, endocrine disruptors, pharmaceuticals and thee residues, which party

aisorb to soll particles aniior biodegrade in the soil, reducing the

‘environmental impact on waters,

Environmental aspects of exereta and greywater use are further discussed in

chapter 8

1.43 Beonomy

"Economic aspects of sanitation are impeetant a both national and houschold levels At

the ational level, planners want to ensure optimal cost-ffectiveness of investments

jn hygiene and ‘sanitation options, ‘These investmen's should give substantial

seonamie returns in health benebts and fine savings (Hutton & Haller, 2004), The

cost-benefit of reducing adverse health and other impacts davmnsteam 4 a result oF

better wastewater ireatment andor reducing vaste discharges into surface waters has

‘not been estimated But is ikely to be as important

‘Several studies have indicated that iis more cost-efewtve to provide funding for

resting sanitation and hygiene demand through promotion than lo hewily subsidize

Sanitation hardwate (Caieneross, 1992; Weight, 1997; Samanta & van Wijk, 1998;

Kolsky & Diop 2004), Most costs associated with gaining access to senitation are

incurred at the housshold level, Consumers want products that are durable ad hat

‘ill not cost Tot to operate and maintain, 1 unlikely that sanitation will become

Ssiainable unless local resourees are ia focus, where people can make a living

supplying serviees to those in need (Kolsky & Diop, 2004) Economic aspects are

further discusced in chapter 9 and in relation to institutional and legal aspects in

chapter 10,

ed Sociocultural aspects and use

Sociocultural Factors ate fundamental for susainabibity, A sanitation faelty without

appeal will not be used Use is linked 10 access and eonvenionee factors, but is also

overed by socal, cultural and refigious belts For wits and women, site acces is

8 major concern The pereeption of osmership or responsibilty #8 crucial and will

alfet, for example, the cleanliness of the facilities and, ultimately, their long-term

success, Sociocultural issues concerning the use of exereta and greywater are further

Aiseussed in chapter 7,

145 Technology function

‘Technology foretion and selection contribute importantly to aspects of sustainability:

‘Technologies selected forthe se use of excrete and greywater should mec ll of the

following sustainability criteria, accounting for robustness and vaiailtes in lod:

bạn

‘+ Health — technologies should provide inherent individual and public heath protection:

+ Environment — technologies should prevent contaminants from reaching

‘groundwater and surface water supplies and provide other environmental protection

+ Economy — technologies should he cost-effective and avilable in a range of

‘options that accommodate differen levels of afordabiiy, and it should be possible to upgrade or improve them as more resources become avilable; + Socigcultral — technologies should be compatible sith local values and beliefs and designed with al potential users in mind

Exoreta and greywater treatment technologies, handling and use are further Aiseussed in chapter 5

*+ population increase and related increased demand for food and fibre:

‘+ growing rveognition ofthe resource value of excreta and greywater and the Tin they contain;

+ - the MDGs, especially the goals for ensuring environmental sustainability and {fo eliminating poverty and hunger

1.5.1 Water scarcity, stress and degradation

Its estimated that within the next 50 years, more than 40% of the work's population will live in countries facing water srs or water scarcity in 1995, SI countries were classified as waterscaree or waterstressed, and it is estimated that 48 and 34 countries will fll into these categories by 2025 and 2050, respectively These rumbers do not include people living in arid regions of large countries where sufficient water is pootly distributed — eg, China, India and the United States oF America (China is predicted to reach ater scarcity by 2050 and India by 2025) (ffimiehsen, Robey & Upadhyay 1998), Growing competition between azriultral and urban areas For high-quality freshwater supplies, pariculary in arid, semi-arid and densely populated regions wil increase the pressure on this resource,

Excreta and greywater can be treated and used close to thei otgin, ether on ste

or in decentralized treatment systems This prevents their discharge into surface waters, thus reducing downistream microbial atd chemical contamination 1 also rediees the coats of developing infrastructure for elaborate conveyance systems (eg sower networks)

Additionally, the “polluter pays” principle is stating to take hold in many places forcing upstream users to teat their wastes to higher standards before discharging them into water bodies Previously, the additional costs of water ieatment oF los of evosystem services (e.g desruetion of fisheries of loss of aesthetic value) were passed on 10 downstream water users Acknowledgement of the concep a integrated

‘Water resources management has Jed to the realization that waste discharges into surface waters have heath, environmental and eeonomie implications for downstream users AS this awareness spreads, it will become increasingly difficult to discharge

Volume 4 Bxoroea

inadequately treated wastes into surface watts Therefore, treatment and use of cexereta and greywater closer tothe point at whieh they are generated become a more aactive option,

1.5.2 Population growth and food production

(Over the next $0 years, most population growth is expected to occur in urban and periurhan areas in developing countries (United Nations Population Division, 2002), For example, a mijority ofthe 19 cities for which the most rapid growth is predicted between 2000 and 2015 (with populations expected to more than double) are in chronically watershort regions ofthe developing world (United Nations Population Division, 2002,

The growth of urban populations especially in developing countries, wil ead 10 several new challenges:

+ greater populations will generate more wastes, especially in and around eis: + onsite waste disposal will he more dificult in many densely populated areas; + orhan agriculture will play a more iasporiat role in sunplying food to city djellers Excreta and greywater will become increasingly important as inputs Exereta and greywater can help t0 improve food production, especially for subsistence farmers who otherwise might not be able 10 afford artificial fertilizers The use of greyiealer for irrigating home gardens may also help to relieve

‘malnutrition and Tood insecurity atthe household level by providing a steady supply

of water for erp itrgaton, allowing the year-long production of vegetables

"The use Of Lealed and souree-separated faoces and urine hes been suggested as suitable for urban agrieuture Wastewater is used already toa large extent in these

‘applications Treated exerela would potentially pose fewer heath risks in these «pes

of applications Estey (2001) has summarized the impact of excreta use in relation to

‘Their dietary intakes are rstrentFmited, and urban residents in developing countries havea lower encray intake than thie rural counterparts Yet poor urban dvellers will

‘ot be able te atfoed imported food

[Lowering the costs of inputs and producing food closer to where people live can reduce food production costs Urban agriculture and home gardening can produce more food per unit space, because food can be grown an roofs on walls and in and around buildings Urban agriculture has enjoyed a revival in the past Few decades (Smit, Rata & Nase, 1996) In greater Bangkok, 60% of the land is under cultivation The demand For food by consumers and for water and nutrients by producers reconnees resources und wastes in a salt, non-pelluing and economic: Eshion Growing food closer to consumers also strengthens the livelihood of loeal communities

‘Recovery and recycling of nutrients feom Inman exereta and other organic matter provide complete nutition for plans, Access to affordable and more nutritious Food

‘wll increase and post-harvest food lasses will be reduved if food is grown and

‘consumed locally This represents a saving in water as well as nutrients,

‘When food is grown farther away fram population centres, not only docs it cost more, but valuable micronutrients are less likely to reach consumers, particularly people with itl income, Urban farming and home gardening, onthe other hand, am result in beter diets, improving macro- and micronutrient intakes as well as the

‘utcitonal status of vulnerable groups, such as women, children, the elderly and the disabled (Maxwell, Levin & Csete, 1998)

1.5.3 Bxereta and greywater as resources

Exereta and greywater contain nutrients and water, which make them valuable resources, The use of exereta and greywater in agriculture aquaculture and oiher settings reduces the need for aniticial ferilizers and is important for nutrient recycling, Some studies indicate that the work's supply of readily availble

‘Phosphorus is lintited and will ran out in 150 years (Rosemarin, 2004), Excreta are an faocessible source of important plant nutrcnts, such as phosphorus, nitrgen and potassium, Exereta use can lp to reduce the mining oF Finite phosphorus reserves and energy expended t0 create antici ferlizers Greywater is mostly used for invgation, as service water of sometimes for groundwater recharge at Tocal scale Is

‘use helps rece the demand for freshwater supply’ and mitigates the stress on siler

[Exereta quantities and composition

Anoually, about 130 million tonnes of fertilizers are sold globally, 639% of which are sold inthe developing world OF this quantity 78 million tonnes are nitrogen and 13.7

"milion tonnes phosphorus The rest represents potassium, sulfor and micronutrients, The excreta fom 6 billion persons contin 27 million tonnes of nitrogen and 3 milion tonnes of phosphorus, This means that one thứ ofthe oes mineral nitrogen use could in thoory be replaced by nisrogen from exerea, Similarly, 22% of the world’s

‘se of mined phosphorus could be replaced by phosphorus from exerts

The major plant auriensniogen, phosphorus and poassium are found in human exereta and thus also in domestic wastewater (Figure {.2), but the contents will vary

‘depending on the food intake Greywater will mainly recycle water and supplies only

‘minor amounts oF nutrients

‘Mass balance and content of macronutrients in excreta

Tite nutrient content in urine and faeces depends directly on the amoonts and quality

of food consumed, Childeen eed nuutients «9 grow: in adults, however, food consumption is mainly for energy, and only minor amounts of nattents ate retained and accumulated in the body Almost ll consumed plant autiens will therefore leave the human body in excreta, Even during adolescence, accumulation of nutrients inthe body is negliibl, caleulated to be less than 2% of the consumed nitrogen between the ages of 3 and 13,

Since most nutrients leave dhe human body in excreta, excreted plant nutrients can

be caleulated From food intake, an which information is readily available Based on Sats from the Food and Agriculture Organization of the United Nations (FAO) (hdpz/Aessao org) on the available food supply in different counties, calculations have been made of amounts and macronutrient content of excreta, insson &

‘Vinmeris, 2004) Table 1.1 provides default values for dhese parameters in Sweden,

These equations can be sed to estimate the average excretion of nitrogen and phosphorus in different counties; see examples in Table 1.2 There tends to be greater

‘variability in values fr potassium

The total per capita annual excretion reported by Gao etal (2002) for China was 44g of iitogen and 0.5 ky of phosphorus, which are in the sume range as the Figutes given in Table L2, where the total excretion has been partitioned berween urine and Taeces

‘The relative umunts of nutrients in urine and faeces depend on the dit: digested rutriets are mainly excreted with the urine, whereas undigested fractions are

‘exereted in the faeces Apprasimately KE% of the excreta nitrogen and 67% of the exereta phosphorus are found in the urine, and the rest are in the facees These Figures tre lower in Ching, where the urine contains approximately 70% of the exereta nitrogen ind 25-60% ofthe phosphorus (Co eta 2002),

Digesubiity also influences the amount of faeces excreted in Sweden, the amount

‘consumption of large amounts of liquid dues the urine,

Use of urine as fertilizer

Urine is rich in nittogen and can be used for Fertilizing most non-nitrogen-fixing crops aller proper treatment to reduce potential microbial contamination, Crops with w high airegen content that respond well 10 ritrogcn fertilization include spinach eaulifiower and maize, Direct use of urine as a plant fertilizer will email the most efcint use of nutrients, but addition af urine to improve composting of earhon-rich substrates is another possibility although it ay result in large antmoni losses) The rutcents in urine are in ionic form, and their plant availabilty and fertizing effet compare sell with those of chemical (amunonium- and urea-based) fertilizers (Kirchmann & Petterson, 1995; Johansson el 2001), When the aittogen content of collected urine is unknown, a concentration of 3-7 of nitrogen per litre m exertion tan he used as a default value (nsson & Vinneris, 2004), On a yearly hasi the amount of nitrogen produced per person equals 30-70 ke, supporting ane crop on 300-400 m’, but up 103-4 times this level may be an optimal application strategy

‘The achieved yield varies depending on the soil conditions As with chemical fertilizers, the effect i lower on soil poor inorganic content, Under these conditions, soil fertility may’ Benet from using both urine and faeces of other organe Fertilizers alternatively applied in consecutive years and for different crops Urine can be applied either undiluted er dilated with water, preferentially just before sowing or dung the

initial plane grow, Once the crop enters its reproductive stage, nutrient uptake is lov, and nutrients are mainly relocated ssithin the plant (Marsehner, 1997) Plants with ineMicient or small root systems (eg carats, onions and letuce) will benefit From repeated applications during the cultivation period (Thonup-Kestensen, 2001) The Lest results of the use of urine asa ferilizer fr barley in Sweden are shown in Box 1

The best fertilizing effect is obtained when the urine is retly incorporated into the sol alter pplication: shallow incorporation is sufficient (Rodhe, Richen Stintzing

& Swineck, 2004) Direct invorporation alo minimizes ammonia losses to the air Surface application generally gives a nitrogen loss above 70% due to ammonia

‘volatilization, and soil ineomparaton is therefore very important (Morken, 1998),

‘Trials with diferent application strategies using urine asa fenilizer for leks gave

a threefold yield increase (Bath, 2003) Application either in two doses or divided nto

‘snaller doses appiod every 14 days gave the same yield and nuttent upiake (Table 1.3), The strategy used in West Alfiea involves the Froquent application of small amounts of urine in order to avoid leaching, Extensive erals have boen performed on

‘various vegetables in Zimbabwe (Morgan, 2004), Results confirm the experience that urine is a quik-acng fenilizer that car be used for most vegetables

Use of faces as fertilizer

acces may contain high concentrations of pathogens, and appropriate tn

therefore racial to ensure it safe use, The iota amount of nutrients excreted is lower

jn facees than in urine, but the concentrations of (especially) phosphorus and potassium are higher in faeces than in urine It fs these two elements that may Significantly inerease the erop yield (Morgan, 2003), The eantent of erganie matter ia faeces also increases the water-holding and ion-buffeing capacities of soils, which is

of importance for improving soil structure and stimulates the microbial activity The Fenilizing eect of faeces is more variable (hân hạt of wine, since the proportion oF nitrogen in mineral form and the content and properties of the organic mater vary depending on the treatment applied

Faecal compost applied together with urine may have advantages, since the Former

‘conditions the soil and the latter provides rapidly accessible niazen, Incineration of faeces reslts in ash with high contents oF phosphorus and potassium as vill as micronutrients, but nitrogen und sulfur are lost to the atmosphere Ash in general (Oshich may also be added to dhe feces) aso inereases the pH and dhe bulTering apacity ofthe soil, The pH inerease i especialy important on soils with very fow pH (4-5) and to ge the all onetit from feilizing with, for example, urine, as shown on experimental plots in Zimbabwe (Morgan, 200),

‘ox 1.1 Urine frtizer fr harley in Sweden

rie wat tt a a eine om bly in Swale daring 1997-1999 Johanson ea

DW dhe, Richer Sizing & Since, 200), Rel showed that henge elec of rin cameondel to abot 91% ofthat of egal aman of ammonite mineral Tels (gue 13) The wine was sea beloe sowing wih conan spear ft

Faccal compost ean be applied as a complete phosphorus-potassium fertilizer or

asa soil improver Approximately 40-70% of the organic mater and somewhat less fof the nitrogen are lost though biological activity and volatilization, Most of the remaining nitrogen will become available to plants during degradation This slow process improves the water-holding and bulfering capacity of the soil The Phosphorus is also partly, but toa lesser extent, bound in organic forms, whereas the potassium is mainly in ionic form and readily available to plants In anaerobic digests, approximately the same proportion of organic matter is degraded as in composting, but the mineralized nitrogen remains within the digested residue and 40-70% of the

nitrogen is in the form of ammonium, which is readily available 10 plants The digested residues make up a well balanced, quick-acting and complete ferilizer (kerhielm & Richert Stizing, 2004) Additonal substrates, uch as animal manure and household waste, ae often added o digestion processes, sthich affects the amount and composition ofthe residue

IE facces are dried rapidly and low moisture levels prevail, the loss of organie

‘matter and nitrogen will be small, Compared with composting, dry storage recycles more organic matter and mirogen to the sol, but the organic mater is less sabe Dried faecal matter is a complete phosphorus-potassium ferilizs, contributing eonsiderable amounts of nitrogen a8 wel

Treated faeces, ina desiccated, incinerated, composted or mixed form, is preferably applied to and incorporated in the ot Zone ofthe soil prior to sowing oF planting, because the high content and availabifity of phosphorus are important forthe evelopment of small plants and oats

“The faecal mate fom one person is enough to fertilize 200-300 m* of wheat at a yield of 3000 kha based on dhe P content Where the soil is devoid of phosphorus, 5-10 times the removal rate can be applied At this application rate, most of the

‘Phosphorus will romain and will improve the sil with significant yield inereases and without negative efects from phosphorus or organic mati Application rates for Farmyard manure in agriculture ae in the range of 20-40 ha If large amounts of lime or ash are used as additives, a minor risk of negative effects exists at pplication rates, due to a high resulting pit (7.5-8) in the soil This risk veil, however, materialize only at extremely high application rates orf the initial pH of the soil already high

In bucket experiments of low-temperature composting of Facees in Zimibebwe, vegetables such as spinach, covo, lettuce, green pepper, tomato and onion were grown

in 10-Tire buckets with poor local topsoil (Morgan, 2003) Growth was compared berseen no additions and plants grown in topsoil mixed with an equal volume of humus derived from eo-composted human faeces and urine A dramatic increase in vegetable yield resulted from the addition of the composted faeces and ute mix t0 oor soil (Table 1.8),

Plant and al pe Growth Viel (girah—VelU(ginak Watney erg weight) is weight) i S00 prove

Topsalfosss nhưng sài rate

Greywater volume and composition

Greywater produetion and composition are dependent on sanitary standard awareness of the nsed for waler conservation, waler availability and raw seater

"

composition (Lens, Zeeman & Lelingi, 2001; Eriksson et al, 2002) Greywater

volume and composition also vary with lfewyle: family size, age of resident, eating

habits and detergents used The main sources af greywater ar laundry, bathroom and

kitchen Inthe following summary, the results of some studies on greywater volume

and composition are presented

‘Greywater volumes produced may be as low a 20-30 irts per person pr day in

poor areas where wate often is hand-catied rom taps (Ridderstolp, 2004; Winblad

‘& Simpson-Heher, 2004) When availability increases the production of greywler

increases, but it seldom exceeds 100 lites per person per day'in developing counties,

‘mn industrialized countries, ereywater produetion is normally in the range of 100-200

lites per person per day (he highest figures are reported from the USA and Canada)

and sometimes exceeds 200 Tres per person per day (rites & Tehobanoglous, 1998;

Dertaglial et a, 2005) in new housing developments in Europe, where awareness of

the need for water conservation is promoted, the per capita daly greywater production

fs less than 100 litres (Table 1.5)

In general, the concentrations of plant nutrients (nitrogen, phosphorus and

potassium) and pathogens of health eoncem are low in greywater (Ottosson &:

Stenstrim, 2003a; Jenssen & Vrile, 2004), due to the fet that the majority of these

are found in excreta, Bacterial indeators tend to overestimate the faecal load in

greywater hecause regrowth may occur (Manville et al, 2001); compared with

shemical biomatkers, a 100- (0 LOD0cfold overestimation of the faecal load was found

(Otosson & Siemmởm, 20032) The microbial contamination of greywater is,

however, significant and must be taken into account when calewating risks and

selecting weatment methods,

Table 15 Examples of greywater prod

mm ‘Greswater redaction titres pe person per Reference

an

‘Germany, Norway and Seen, 100 Riera 200): Wiad &

Sergi dài D605) Developing ions 2020 Rider 2004); Wha Sinpsontlebat 2008)

‘hosphorus-containing detergents are used, concentrations (picaly range from 3 0 7 mg/l If phosphate-ree detergents are used the concentrations are about 1 mer Greywater contebutes 10% oF les ofthe total nitrogen content in wastewater, and the nitrogen concentration in greywater is often 10 mgll or less, prior to (reatment (Winners, 2002; Jenssen & Vee, 2008),

‘Greywater contains 30% or more of the readily degradable organic matter in household sewage — measured as biological (BOD) oF chemical (COD) oxygen demand — but the concentrations are highly variable, depending on household practices In industrialized countries, excessive amounts of detergents, including Shampoos, shower oils, cleansing powders, ete are common and responsible for substantial BOD input, in addition to grease and oil used in food preparation In silures where use of cooking oil is common, the ereywaterorpanie content becomes very high and may call for special care when designing treatment systems Ifcolecied separately, the oil and grease can be processed to biodiesel (Zhang etal 2003), but thy can aio inerease biogas yield in anaerobic digestion, Examples of coneentrations

of various water quality parameters found in untested or primary weated greywater are presented in Table 1.6

The concentrations of ution: in greywater depend on the per capita mass Aisehatge anu the water use The per capita discharges under Swedish conditions are presenied in Table 1.7,

In the sites listed in Table LÍ, phosphorus-containing detergents were use According to Norwegian studies, the por capita mass discharge of phosphorus 1s reduced to 0.2 mul with phosphorus-free detergents (enssen & Veile, 2004) The

‘malor part of the heavy metal load in household wastewater is found in the greywater fraction (Vinneris, 2002), and concentrations of heavy metals can therefore be expected 10 be ofthe same level asin combined household wastewater

1.54 Millennium Development Goals

[At the 2002 World Summit on Sustainable Development in Johannesburg elebal leaders agreed to adopt a sanitation coverage target — namely, "to halve, by the year

2015, the proportion of people who do not have access to basie sanitation” (Uiited Nations, 2002) Expanding sevess to and proper use of improved sanitation facilites

‘would have far-ranging positive health consequences and would support mestng the relevant targets of the Mallennium Development Goals,

To achieve the sanitation target under MDG7, WHO estimates that 1.9 biflion people will need to gain access to improved sanitation by 2015 — 1 billion urban

‘Syellers and 900 million rural gellrs, This figute takes into account the project’ population growth As of 2002, 79% ofthe unserved worldwide (.e, 2 billion people) lived in rural areas Expanding access to basic sanitation in rural areas is an urgent pritity (WHO/UNICEF, 2008) A large percentage of population growth, however, i fexpecied to occur in urban and periurkan areas (ollen in slums or informal sedtemiens) in developing counties,

Man cf the 2.6 billion people without improved sanitation are among those hardest to reach: families living in remote rural areas and urban slums, families displaced hy war and famine and families mited io the poverydlsease tap (WMHOLUNICEF, 2009)

Table 1.6 Concentration of some water get parameters found i ateated or primary aed (ei ta feat greener

Fanner BOD COD Suspended Total NH: KEM Toot ag (xu) sods Ney Ning) Pcolors Faccl

Nemay MO SỬ - ẤM CAN A8 haw Sermo 2001)

‘whole, Because much of dhe wastewater is Hkely to be discharged into water bodies without adequate eatment, thus exposing dovenstream users 10 human pathogens through ungeated drinking-water, food or contact with contaminated water

Table 1.9 Greywater volume al eancntralions of eons water quay parametts

reser colecied from Swedih co hoening developments cermpared with Swedish norm

BOD, mendayloriol suy denang

Sours Caleta tm Viner tal 2006)

Therefore, if effective treatment were available at the household level, prior to discharge of waste into the environment or use, the health of downstream users would

he bor protected

Poverty has long been recognized as one of the primary impediments 1 sustainable development In many countries, poor subsistence farmers do not have aovess to water resources and may not have money to buy Fertilizers, The use oF exerein and greywater in agriculture has the potential to afTcet poverty positively in several way

+ improved household food security and nutritional variety, which reduce inalnativion:

+ nreased income from sale of surplus eros (the use of exerts and

‘may all cultivation of erops year-round in some locations),

+ money saved on Ferilizer, which ean be put to other productive uses