Pathogen Environmental
Monitoring
Kimberly Bukowski
Cornell Dairy Foods Extension
Importance of PEM
•
•
•
•
•
Preventing recalls
Long term program improvements
Verification of cleaning and sanitizing program
Verification of hygienic/transition areas
Required written records under FSMA
Pathogen Control Principles
Separate
Raw from
RTE
GMPs and
Controlled
Conditions
Sanitary
Facility and
Equipment
Design
Effective
Cleaning &
Sanitizing
Procedures
/Controls
PEM
Effective
Pathogen
Control
Separate Raw from Ready To Eat (RTE)
GMPs and Controlled Conditions
Sanitary Facility and Equipment Design
Effective Cleaning & Sanitizing
Procedures and Controls
Pathogen Environmental Monitoring
Root Cause Analysis:
Eliminating Repeat Problems
What do I
already
know?
Define
problem
Information
gathering
Potential causes
RCA Methods
The 5 Whys
• Keep asking ‘why’
until the root cause
is identified
RCA Methods
Fishbone Diagram
• Used identify possible
causes for a problem
• Can induce a different
type of thinking
Myth Busting is Critical
Use data and logic to focus resources
Common misconceptions about root cause
• “The organism is airborne”
• “Raw meat is (20-40% Lm +) highly contaminated
with the organism”
• “It cannot be removed from the processing
environment”
• “Drains will always be positive”
• Listeria species on contact surfaces means product
is positive for Listeria monocytogenes.
RCA-based Corrective Action
• Identify corrective action
to prevent reoccurrence
– If implemented earlier,
would it have prevented
the event?
• Implement solution
Developing a Sampling Plan
• Site and product specific
– Wet or dry environment based on product
• Incorporate typical, rotating, and random sites
Pathogens of Concern
Pathogens typically monitored in PEM programs
• Listeria monocytogenes
• Salmonella
• Cronobacter spp.
– Typically in infant formula plants
– Occasionally monitored in other powdered product
facilities
Index and Indicator Organisms
• Index organisms: markers whose presence relates to the
possible occurrence of ecologically similar pathogens (e.g.,
Listeria spp.)
• Indicator organisms: markers whose presence relates to the
general microbiological condition of the food or environment
(i.e., hygienic quality) (e.g., coliforms, Enterobacteriaceae, SPC)
– Negative tests for indicators do not indicate absence of
pathogens
• Long-term trending and analysis needed for pathogens, index,
and indicator organisms
Listeria monocytogenes
Salmonella
Testing Locations
Minimum
Sampling
Frequency
Number of
samples
Zone
Sampling Site
Examples
Microbiological
Analyses
1
Direct product contact
surface
Packaging, utensils, fillers,
inside vats, employee
hands
Indicator organisms,
pathogens (under
special conditions)
Weekly
Product
dependent
Non-product contact sites
adjacent to Zone 1
Areas above packaging,
equipment framework,
control panels, overhead
pipes over Zone 1,
computer screens
Pathogens
Weekly
10-15
Non-product contact sites
adjacent to Zone 2, areas
of cross-contamination
risk
Floors, walls, ceilings,
condensate drip pans,
forklifts, carts, trash
containers, pallets, floor
mats, drains,
brooms/mops/squeegees
Pathogens
Weekly
10-15
Areas outside processing
Hallways, loading docks,
warehouses, locker
rooms, cooler/freezers,
Pathogens
Monthly
5-10
2
3
4
Ideal Indicator Sites
• Locations close to the growth niche that can
identify an active growth niche
• Locations that can identify suspect organisms
before they become attached to or imbedded
within the equipment.
• Z4 to Z3 Transfer areas
• Sanitary Facility Design issues
Testing Considerations
• Prioritize sampling sites
– After kill step (pasteurization)
– Before final packaging
• Focus attention on zones 2 & 3.
• Sites with historic positive results
• Reference plant layout, traffic patterns and
hygienic zone areas to help determine
additional sites
Hygienic Zoning Areas
Zone 4
Zone 4
Zones 3 & 4
Zones 1 & 2
How do these relate
to sampling zones?
Zones 1 & 2
Adapted from Food Safety Preventive Controls Alliance
Offices
Assemble, Wrap Area
Hall
Hall
Ambient
Ingr. Storage
Refr. Ingr.
Storage
Non-manufacturing,
Entry area
Hall
Hall
Metal
Detect
Fill, label
Spiral Freeze
Cook Area
Mix Room
Utensil and Small
Equipment Cleaning
Room
Transition, Basic GMP, Primary pathogen control area –
CONTROLLED ACCESS
Adapted from Food Safety Preventive
Controls Alliance
Women’s Room
Packaging
Storage
Carton
Assembly
Hall
Frozen
Storage
Lab
Men’s Room
Shipping & Receiving
Maintenance
Mechanical
Example Hygienic Zoning Areas
Traffic Flow:
Product, Equipment, and Personnel
Timing
• Pre-operational
• During Production (recommended)
• Post-rinse
Frequency
• Daily
– As a corrective action for a specified amount of
time
• Weekly
– Zones 2 and 3
• Monthly
– Zone 4
Number of Samples:
Considerations
• Based on facility size
• Aging facilities=increased risk=increased sampling
• Geography of facility
– Proximity to hazards
• Budget
• Manpower
Number of Samples:
Recommendations
Minimum
• 30 sponges per 50,000 square feet
– Raw area: 7
– RTE/High Hygiene: 20
– Zone 4: 3
Best in Class
• 55 sponges per 50, 000 square feet
– Raw area: 14
– RTE/High Hygiene: 35
– Zone 4: 6
Innovation Center for US Dairy
Growth Niches
Locations harboring the organism after the routine
sanitation process for that area has been completed.
Methodology
• Sponge
– used with gloves
– most commonly used
• Handled sponge
• Crevice Swabs
Sponges
Crevice Swab
Small Crevice Swab
Cornell Dairy
Blend Room
Zone Mapping
Zone 3
Zone 2
Zone
3
Zone 2
Zone 2
Zone 3
Zone 3
Zone
3
Zone Mapping
Zone 2
Zone 2
Zone 2
Zone 3
Zone 3
Zone 3
Zone 3
Zone 3
Zone 2
Zone 2
Zone 3
Zone Mapping
Cornell Dairy 8 oz. Bottled Milk Filler
Zone 3
Zone 3
Zone 3
Zone 1
Zone 1
Zone 2
Zone 2
Zone
1
Zone
2
Zone 3
Zone 3
Zone 2
Zone 3
Zone 3
Zone Mapping
Zone 1
Zone 3
Zone 2
Zone 1
Zone 1
Zone 1
Zone 3
Zone 3
Zone 2
Zone 3
Zone 2
Zone Mapping
Zone 3
Zone 3
Zone 3
Exterior Tank
not near lid
Zone 3
Exterior: Zone 3
Interior: Zone 2
Zone 3
Interior
Zone 1
Zone 3
near lid
Zone 1
Zone 2
Zone 3
Zone 3
Cornell Dairy
Cultured Products Room
Zone 2
Zone 3
Zone Mapping
Zone 3
Zone 3
Zone 2
Zone 2
Zone 1
Zone 3
Zone 1
Zone 1
Compositing
• Approach 1:
– Samples from multiple sites
– Single sponge
– Single Enrichment
• Approach 2:
– Samples from multiple sites
– Multiple sponges
– Single Enrichment
Results
•
•
•
•
Send samples to a certified lab
Review results upon arrival
Apply corrective actions
Monitor trends
Follow-Up and Corrections
• Plant specific and may differ by zone
• Consider frequency of sampling vs. root cause
analysis
• Intensified cleaning and sanitizing required
• Long-term trending and analysis
– Pathogens
– Index and indicator organisms
Corrective Actions
• Positive samples need follow-up: re-testing
and vector swabbing
• Shutting down problem areas
• Written records
5/15/2013
23
5/23/2013
Thorough cleaning with an acid cleaner (vs. our old chlorine bleach) was performed
x
ADA 6/13/2013
Vector Swabbing
Additional samples should be taken from
environmental area that showed positive results
Investigation of a Positive Finding
• Review infrastructure and equipment in the
area
• Targeted cleaning
• Review records
• Corrective action
– Location (zone)
– Trends
Tracking Results
• Track and trend environmental data
• Collect and record data to provide actionable
information
• Establish a baseline to monitor trends
• Detection of a pathogen in Zone 1 requires
immediate action as product may be
contaminated
Tracking Results Example
Map with Areas and Positive Swabs
Map with Areas and Positive Swabs
Verification Swabbing:
ATP Swabbing
• Rapid test for presence of organic material
• Determines relative cleanliness of the surface
• Sanitation monitoring and verification activity
Verification Swabbing:What is ATP?
• ATP is the “energy currency” molecule of all
living organisms
• In cells, ATP loses one or more phosphates to
release energy
Verification Swabbing:
Allergen Swabbing
• Control test designed to prevent cross-contact
from allergenic food soil on process equipment
• Sanitation monitoring and verification activity
• Planning for allergen testing requires clear
communication and coordination with senior
management to hold or destroy product, pending
results of the testing
Environmental Monitoring Program Revisions
• Review the program at least annually and
modify as necessary when:
Indicated by corrective actions
When ingredients and processing changes are made
Following adverse events
When equipment modification, repairs, replacements are
made
– When there are consistently no positive findings
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FSMA and Environmental Monitoring
• Environmental Monitoring as a Verification Activity:
– Verify the effectiveness of sanitation programs
– Verify that hygienic zoning is working
• Understand “normal” environmental conditions vs. something
has changed or something unusual is going on
– Not a specific preventive control, though records are
required for a food safety plan
• A useful program diligently tries to find the organism
Adapted from Food Safety Preventive
Controls Alliance