02. Matthew Lau [Compatibility Mode]

The Role of Water in Food Safety
and Sustainability
Mathew Lau, Ph.D.
(ILSI-Europe Emerging Issues Committee)
Peter McClure, David Cunliffe, John Fawell, Liesbeth Jacxsens, Lise Korsten,
Kate Medlicott, Maria Pepe Razzolini , Mieke Uyttendaele, Pratima Rao Jasti,
Philip Amoah, Pay Dreschel , Sarah Cahill, Marisa Caipo, Maria Campos,
Charles Gerba, Lee-Ann Jaykus , Gertjan Medema, Massimo Signorini and
Flavio Zambrone
ILSI SEA Region 6th Asian Conference on Food and Nutrition Safety (Nov 2012)
http://www.ilsi.org/SEA_Region/Pages/ViewEventDetails.aspx?WebId=4D540914-EEB6-40E4-89EB-0B73BA3D76C1&ListId=478BE3CB-581B-4BA2-A2808E00CCB26F9C&ItemID=66
ILSI Europe Water Initiative
Presentations @ Conferences
2
Expert Group
Dr PeterMcClure
- Chair -
Unilever
UK
International Water Management Institute
- IWMI
Food and Agriculture Organization - FAO
GH
CO
AU
UK
US
BE
US
ZA
SG
NL
BR
AR
Prof Mieke Uyttendaele
Dr Flavio Zambrone
Universidad Javeriana
Department of Health
Independent Consultant
University of Arizona
University of Ghent
North Carolina State University
University of Pretoria
Nanyang Polytechnic
Delft University of Technology
University of Sao Paulo
National
Institute
of
Agricultural
Technology
Ghent University
Planitox
Dr Pratima Rao Jasti
ILSI Europe
BE
Dr Philip Amoah/Dr Pay Dreschel
Dr Sarah Cahill/Dr Marisa Caipo/
Dr. Vittorio Fattori*
Prof Maria Claudia Campos Pinilla
Dr David Cunliffe
Prof John Fawell
Dr Charles Gerba
Dr Liesbeth Jacxsens
Prof Lee-Ann Jaykus
Prof Lise Korsten
Dr Mathew Lau
Prof Gertjan Medema
Prof Maria Tereza Pepe Razzolini
Dr Marcelo Signorini
*Observer
IT
BE
BR
Background
4
Water Scarcity
• Because of climate change and (associated) water
shortages, there is a need to find alternative
sources of agricultural water (e.g., wastewater)
• But guidelines are needed to assure resulting
product is safe
5
Table of Contents
1. Introduction
2. Fresh Produce and Microbial Safety Concerns
3. The Behaviour of Microbial Hazards in the ProductionProcessing Environment
4. Good Agricultural Practices (GAPs), Good Manufacturing
Practices (GMPs), Detection and Monitoring
5. Waters Used in Fresh Produce Production
6. Waters Used in Fresh Produce Packing and Processing
7. Microbial risk assessment
8. Data Gaps and Recommendations
Epidemiology
•
Produce associated outbreaks not uncommon.
•
True disease burden is unknown due to underreporting.
•
Viruses/parasites relatively under-recognized; with
majority being Salmonella and E. coli O157:H7
•
There are a handful of outbreaks linked directly to
contaminated production (irrigation) and
processing (wash) waters
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Water as a source of contamination
Spinach-associated
Escherichia coli O157:H7
Outbreak in US (2006)
the river functioned as
a vector between the
contaminated feces
and the irrigation wells
US/Canada
1996) berries
and Cyclospora
cayetanensis: spraying
with pesticides or
fungicides prepared
using contaminated
water
Jalapenos peppers
Salmonella Saintpaul ,
US (2008). The outbreak
strain was isolated from two
environmental samples,
agricultural water, and Serrano
peppers on a farm in Mexico
which grew the peppers
Australia (2006): papayas and
Salmonella Litchfield : washed with water
from a source later determined to contain
other serotypes of Salmonella
US (2011) melons and Listeria
monocytogenes : water/wet surfaces
in processing environment facilitates
survival and persistence
8
Water as a source of contamination
Low Infective Dose
Contamination
Low levels of pathogens
can pose Public Health
Concern
9
Water as a Contamination Source
The importance of water, relative to other
contamination sources (e.g., the hands of workers,
surface sanitation, animal encroachment, etc.) is not
well known.
10
Impact of Crop and its Production
-Plant physiology (respiration
rate, climateric or not,
damage/bruises)
-Antimicrobial components: e.g.
carrots, essential oils
-Microbial ecology, competitive
flora
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Fresh Produce Production
• The quality of water used for irrigation has the greatest
potential impact on the microbiological safety of fresh
produce
• There are two general sources of irrigation water:
– Surface water (more prone to contamination)
– Ground water reserves (less prone to contamination)
• Treated wastewater is increasingly being used for
irrigation purposes but poses the following risks:
– Inadequate treatment
– Mixing water sources
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Relative Risk?
• Depend on water source
• Relative risk:
– Tap/municipality water (potable)
– Ground water
– Surface waters
– Rain water
– Drain water
– Effluents
– Storm water
– Untreated wastewater ? ?
Irrigation Method
• Irrigation methods vary - Simple manual vs automated
practices (sprinklers, canals/furrows or drip irrigation)
• Controls must be specific to the method. A few general
principles:
– Maintenance of water delivery systems
– Cessation of irrigation several days prior to harvest
– Limit direct contact between edible plant tissue and
irrigation water (splashes)
– Disinfection and decontamination treatments
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Fresh Produce Packing and
Processing
• Many guidelines and regulations that have requirements
for post-harvest process water quality.
15
Water Quality Requirements
On farm
Processing
(on or off
site)
Ready to
Eat (RTE)
Requirements for microbial water quality increase as the
product progresses from field to final processing
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Fresh Produce Packing and
Processing
• Key mechanisms to limit microbial contamination in
packing and processing include:
–
–
–
–
–
Use of high quality water
Good equipment sanitation
Sequential washing steps
Use of disinfection techniques
Control biofilms
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Control: GAPs and GMPs
• In some countries, adherence to GAPs is regulated by
law; in others, GAPs are guidance to the industry
• Voluntary standards (such as Global GAPs) have also
been instituted, largely to ally retail and consumer
concerns, and to promote trade
• Safety of fresh produce (and its associated water) is
assured at the packing/processing phase by Good
Manufacturing Practices (GMPs), prerequisite programs,
and in some instance, HACCP
• Third party certification is an emerging means by which
to assure GAPs compliance
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Country
Australia
N. Zealand
c
Australia
N. Zealand
Australia
N. Zealand e,f
Canada
Water Type
Regulation
Irrigation water for non
food crops : Secondary
treatment or primary
treatment with lagoon
detention
Guideline
Reference
< 1000 E. coli per 100 mL
Australian Guidance for
Water Recycling, 2006
< 1 E. coli per 100 mL
Australian Guidance for
Water Recycling, 2006
Guideline
< 100 E. coli per100 mL
Australian Guidance for
Water Recycling, 2006
Guideline
< 1000 total coliforms per 100 mL
Steele & Odumeru, 2004
Irrigation water for
Guideline
commercial crops raw or
unprocessed : Advanced
treatment to achieve
total pathogen removal
required
Irrigation water for
commercial food crops:
Secondary treatment
with >25 days lagoon
detention and
disinfection
All
Criterion a, b
Selected
Irrigation
Water
Quality
Guidelines
and
Regulations
< 100 fecal coliforms per 100 mL
Italy
Wastewater
Regulation
< 10 E. coli per 100 mL
Salmonellae absent in 100 mL
Spain c
Wastewater
Regulation
< 100 E. coliper 100 mL
Angelakis et al., 2007; Cirelli
et al., 2008
Iglesias et al., 2010
< 1 nematode egg in10 L
USA
Surface water
Guideline
<126 E. coli per 100 mL
U.S. EPA, 2003; LGMA, 2012
USA
Wastewater
Guideline
Fecal coliforms absent per 100 mL
U.S. EPA, 2004
Regulation
< 2.2 totoal coliforms per 100 mL
Steele & Odumeru, 2004
California
(USA)
WHO
Fecal coliforms absent
Wastewater
Guideline
< 1000 fecal coliforms per 100 mL
< 0,1 nematode egg per L
Blumenthal & Peasey, 2002;
WHO, 2006
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Microbiological Standards?
• Most guidelines and regulations are heavily based on
microbial standards
• An alternative is the World Health Organization
guidelines for use of wastewater in agriculture, which
have been revised substantially:
• The fecal coliform guideline has been replaced by health based
targets defined through attributable risks and DisabilityAdjusted Life Years (DALYs)
• Governments in developing countries have been given greater
flexibility in achieving these targets (WHO, 2006).
• Requirements for restricted vs. unrestricted irrigation (i.e. for
crops that are to be eaten uncooked vs. cooked)
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Risk Assessment
• Most MRAs to date has focused on evaluating human
health risks associated with:
– Use of treated wastewater for irrigation
– Various irrigation type and irrigation conditions
– Enteric viruses rather than bacteria
• Universal use of MRA to manage fresh produce safety
risks is complicated by :
– Vast number of produce items and production/
processing conditions
– Lack of data for many parameters
• There are, however, some examples
(http://www.fao.org/food/food-safety-quality/scientific-advice/jemra/en/)
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Data Gaps/Needs
The relative importance of contaminated water to the
burden of produce-associated foodborne disease
Characterization of produce-associated sporadic
disease and outbreaks
Rapid & effective methods to enable safe use of
wastewater for irrigation
Faster and more reliable testing of water for potential
pathogen contamination
Reliable data for MRA
Indicators; Predicting pathogen emergence
Role of global climate change
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Conclusions
Recognition that global climate change will affect water
availability and quality worldwide.
The Global market presents an important opportunity for
farmers in developing countries but safety and quality are
important success factors.
Local regulations (where absent) for best practices need
to be set by government departments or agricultural
associations and implementation verified at farm level.
Transparency and simplicity are vital for maintaining the
confidence of consumers.
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