The Pest Sighting Behind the Dry Store
You are the food safety supervisor at a bakery/cafe. During a Tuesday morning walkthrough you find: (1) mouse droppings on a shelf in the dry store, behind a stack of flour bags; (2) a gap of about 15 mm under the dry store door; (3) a torn fly screen on the back door, which is propped open for ventilation; (4) a bag of flour with a chewed corner; (5) a sticky trap behind the shelf with two mice on it, dated 'three weeks ago' and not replaced. The dry store is next to the prep area where dough is mixed and where RTE sandwiches are made. The pest control contractor visits monthly; the last report noted 'activity in dry store - monitor'. The owner says 'it's a bakery, there are always a few mice, the traps are doing their job'.
1. Assess the pest problem and explain the specific food safety risks it creates in this premises, including why the location next to the prep area matters.
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Assessment
- This is not 'a few mice' - it is an established infestation in a dry store. Evidence: droppings on a shelf, a chewed flour bag, two mice caught on an old trap, and a contractor report already flagging activity. The traps are catching mice, which means mice are present and breeding nearby.
- The 15 mm door gap and the torn/propped-open back door are entry points. A mouse can get through a gap of about 6–7 mm; 15 mm is an open door. The propped door also lets flies in.
- The chewed flour bag shows product is being accessed. The droppings show contamination of the storage environment.
Food safety risks
- Direct contamination: mouse droppings and urine can carry Salmonella (e.g. S. Enteritidis), Listeria and E. coli. Droppings on a shelf above/beside flour can contaminate bags, and from there hands, utensils and dough.
- Indirect contamination: mice walk on shelves, bags and surfaces, then the same surfaces are touched by staff who then handle RTE sandwiches. The dry store is next to the prep area - that is the critical point. Flour dust, bags and staff movement connect the two spaces, so pest contamination in the dry store is a direct route to RTE food.
- Product contamination: the chewed flour bag must be treated as contaminated. Do not use it.
- Flies: the torn screen and propped door allow flies, which are mechanical vectors for Salmonella, E. coli and Staph. aureus.
Why the owner's view is wrong 'Traps are doing their job' is a misunderstanding: traps are monitoring and control, not proof of control. Catching mice means the problem is active. An old trap dated three weeks ago is not being monitored, so the contractor's 'monitor' recommendation has not been acted on.
2. Set out the corrective actions you would require, covering the dry store, the building, the pest control programme and the product, and state what records you would keep.
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Immediate actions (today)
- Product: discard the chewed flour bag and any bag with evidence of gnawing or droppings. Record quantities. Do not use.
- Clean: remove all stock from the dry store, clean shelves and floor, and disinfect. Use a damp method (not dry sweeping) to avoid spreading droppings and dust. Wear gloves and a mask; wash hands afterwards.
- Inspect: check all bags and containers; transfer opened dry goods to sealed, pest-proof containers (e.g. lidded bins).
- Traps: replace the old sticky trap, date it, and add more traps along walls and behind shelves. Check and date traps at least weekly.
Building and entry points 5. Door gap: fit a door seal/brush strip to close the 15 mm gap. 6. Back door: repair or replace the torn fly screen; keep the door closed. If ventilation is needed, fit a screen or air curtain - do not prop the door open. 7. Gaps and pipes: seal any other gaps around pipes and walls.
Pest control programme 8. Escalate with the contractor: from 'monitor' to active treatment (baiting, trapping, proofing). Ask for a written report and a follow-up visit within days, not a month. 9. Increase monitoring to weekly checks of traps and dry store, recorded. 10. Review the contract - monthly visits are not adequate for an active infestation.
Records to keep
- Pest sighting log (date, location, evidence, action).
- Trap check record (date, number caught, trap replaced, initials).
- Corrective action record for the chewed product (disposal).
- Cleaning record for the dry store.
- Maintenance records for the door seal and fly screen.
- Contractor reports and follow-up actions.
Follow-up
- Re-inspect within 7 days; escalate to the owner if activity continues.
- Brief staff: report sightings immediately, keep dry goods sealed, keep doors closed.
- If the owner refuses the building works, record that refusal in writing - it is a legal compliance issue, not a preference.