---
title: "Compost & Mould Poisoning in Pets UK"
description: "UK compost bin and mouldy food poisoning in dogs and cats — tremorgenic mycotoxins, symptoms, garden risks, and Animal PoisonLine after scavenging."
url: "https://pethealth.org.uk/health/compost-mould-poisoning-pets-uk"
canonical: "https://pethealth.org.uk/health/compost-mould-poisoning-pets-uk"
date_published: "2026-06-01"
date_modified: "2026-07-10"
source: "PETHEALTH+"
---

# Compost & Mould Poisoning in Pets UK

**Mouldy food and compost produce mycotoxins that can kill UK pets.** Tremorgenic toxins cause vomiting, tremors, and seizures within hours. Secure compost bins, never feed mouldy scraps, and phone your vet or **Animal PoisonLine on 01202 509000** immediately if your pet scavenges mouldy material.

## Why compost and mould poison pets

**Mycotoxins** are poisonous chemicals produced by fungi growing on decaying organic matter. Compost heaps, food waste bins, and mouldy leftovers are ideal environments for toxin-producing moulds.

UK pets are poisoned when they:

- Raid **kitchen compost caddies** or outdoor compost bins
- Eat **mouldy bread, pasta, rice, or nuts** from counters or bins
- Scavenge **mouldy food** dropped at barbecues, picnics, or bird tables
- Dig into **garden compost heaps** or leaf mould piles
- Eat **mouldy windfall fruit** or fermented vegetation in autumn

Dogs are the most common victims due to scavenging behaviour. **Cats** accessing indoor caddies or outdoor bins are also at risk.

## Tremorgenic mycotoxins — the main threat

The most dangerous compost-related toxins in UK pets are **tremorgenic mycotoxins** — including roquefortine C and penitrem A from certain mould species.

These toxins attack the **nervous system**, causing:

- Muscle tremors — fine shaking to violent jerking
- Rigidity and hyperthermia (high temperature)
- **Seizures**
- Collapse and death in severe cases

Tremorgenic poisoning can progress **rapidly** — from mild tremors to seizures within hours. Early veterinary treatment is essential.

Other mycotoxins cause primarily **liver damage** — similar to some mushroom poisons — with vomiting, jaundice, and bleeding. Aflatoxins from mouldy nuts and grains target the liver.

## Symptoms of mould and compost poisoning

Signs typically appear within **30 minutes to a few hours** after ingestion:

| Early signs | Severe signs |
|-------------|--------------|
| Vomiting and retching | Seizures |
| Drooling | Collapse |
| Restlessness | Hyperthermia — hot body |
| Fine muscle tremors | Breathing difficulty |
| Agitation | Coma |

Some dogs show **ataxia** — wobbling and inability to walk normally — before tremors become obvious.

Do not assume mild tremors will pass without treatment. Toxins can escalate to life-threatening seizures.

## Common UK exposure scenarios

Typical cases involve:

- **Kitchen compost caddies** left open on worktops — dogs and cats pull out mouldy tea bags, bread, and pasta
- **Garden compost bins** with loose lids — dogs knock them over in gardens
- **Autumn windfall apples** fermenting on lawns — alcohol and mould together worsen toxicity
- **Bird table scraps** and mouldy fat balls
- **Bin raiding** on collection day — mouldy food waste in wheelie bins
- **Forgotten lunchbox contents** in children's bags or cars

Autumn and warm wet weather increase mould growth — risk peaks when compost heaps are damp and warm inside.

## Compost vs other garden poisons

Compost poisoning is distinct from:

- **Slug pellets (metaldehyde)** — causes rapid tremors and seizures too — see [slug pellet poisoning](/health/slug-pellet-poisoning-pets-uk)
- **Onion and garlic** in food waste — causes delayed anaemia — see [onion and garlic poisoning](/health/onion-garlic-poisoning-pets-uk)
- **Grapes and raisins** in discarded baking — kidney failure — see [grape poisoning in dogs](/health/grape-poisoning-in-dogs)
- **Xylitol** in sugar-free gum thrown in bins — see [xylitol poisoning in dogs](/health/xylitol-poisoning-in-dogs)

Food waste often contains **multiple hazards** — mould toxins plus toxic foods. Treat any compost or bin scavenging as potentially serious.

## Emergency treatment

If your pet ate compost or mouldy food:

1. **Phone your vet or Animal PoisonLine (01202 509000) immediately** — treat as emergency
2. Report what was eaten, estimated amount, and time
3. **Do not induce vomiting** unless your vet advises — some pets already seizuring
4. Keep your pet **cool and calm** — hyperthermia worsens outcomes
5. Bring a sample of the **mouldy material** if safely collectable
6. Out of hours: [Vets Now emergency clinic finder](https://www.vets-now.com/find-an-emergency-vet/)

Veterinary care may include:

- **Activated charcoal** if ingestion was recent and no seizures yet
- **Anti-seizure medication** — diazepam or levetiracetam
- **Muscle relaxants** for severe tremors
- **IV fluid therapy** and temperature monitoring
- **Liver support** if hepatotoxic mycotoxins suspected
- Hospitalisation until tremors resolve — often 24–48 hours

Prognosis is good with prompt treatment for most tremorgenic cases. Delayed care increases seizure complications and death risk.

## Prevention in UK homes and gardens

### Kitchen

- Use **sealed compost caddies** — never leave open on counters
- Empty caddies frequently into outdoor bins
- Keep caddies in **closed cupboards** or behind child-proof latches if pets counter-surf
- Dispose of mouldy food in **outdoor wheelie bins** with secure lids — not indoor bins pets can open

### Garden

- Use **closed compost bins** with locking lids — not open heaps if you have dogs
- Fence off traditional compost heaps and leaf mould piles
- Clear **windfall fruit** from lawns regularly in autumn
- Secure **wheelie bins** — store behind gates if dogs raid bins
- Clean **barbecue and picnic areas** immediately after eating

### Training and walks

- Teach strong **"leave it"** for scavenging on walks
- Supervise dogs in gardens — compost bins tip when dogs lean on them
- Avoid letting dogs dig in **leaf piles** where mould develops

For mouldy vegetables in the fridge — throw in outdoor bin, not open compost accessible to pets.

## Mouldy food — never feed pets

Some owners believe dogs can eat stale bread or mouldy cheese because "dogs eat anything." This is dangerous. **Never feed mouldy food** intentionally.

Mould on cheese, bread, nuts, and grain products carries tremorgenic and liver toxins. If you would not eat it, your pet should not either.

Safe vegetable scraps without mould are a separate topic — see [what vegetables can dogs eat UK](/health/what-vegetables-can-dogs-eat-uk). Mouldy versions are toxic.

## When to see an emergency vet

Seek **immediate emergency care** if your pet:

- Ate compost or visibly mouldy food — even a small amount
- Shows tremors, wobbling, or muscle rigidity
- Has seizures or collapse
- Vomits repeatedly with agitation or restlessness
- Feels unusually hot — hyperthermia from tremorgenic toxins

For general poisoning first steps, see [pet first aid UK](/health/pet-first-aid-uk) and [when to see an emergency vet UK](/health/when-to-see-emergency-vet-uk).

## FAQs

### Can compost poison dogs?

Yes. Compost heaps and mouldy food produce mycotoxins — especially tremorgenic toxins — that cause vomiting, tremors, seizures, and death in dogs. Even small amounts of mouldy bread, pasta, or compost material can be dangerous.

### What are signs of mould poisoning in pets?

Vomiting, drooling, muscle tremors, rigidity, fever, seizures, and collapse. Signs can appear within 30 minutes to several hours after eating mouldy food or compost. Severity depends on the toxin and amount eaten.

### Are compost bins dangerous to cats?

Yes. Cats can access kitchen compost caddies or garden bins and eat mouldy scraps. Cats are also sensitive to mycotoxins — tremors and seizures require emergency vet care.

### How do I keep pets away from compost?

Use sealed compost bins with secure lids, never leave kitchen caddies open, fence off garden compost heaps, and clear dropped food from barbecues and picnics immediately. Train dogs to leave mouldy items on walks.

## Sources

- [Animal PoisonLine](https://www.animalpoisonline.co.uk)
- [PDSA — Poisoning in pets](https://www.pdsa.org.uk/pet-help-and-advice/pet-health-hub)
- [RSPCA — Keeping pets safe](https://www.rspca.org.uk/adviceandwelfare/pets)
- [BVA — Pet poisons](https://www.bva.co.uk)

Canonical HTML: https://pethealth.org.uk/health/compost-mould-poisoning-pets-uk
Last modified: 2026-07-10