🚫 Why Glutaraldehyde Is No Longer Used for Endoscope Disinfection in the UK

Date: July 2025

Author: FRCPathPrep Editorial Team

Category: Infection Control | FRCPath Part 2

💡 Quick Summary

Once widely used for disinfecting flexible endoscopes, glutaraldehyde has now been almost entirely phased out in UK healthcare. If you're preparing for FRCPath Medical Microbiology Part 2, understanding why is essential for OSPE, viva, or infection control SAQs — especially those involving decontamination failures or occupational health issues.

🔬 What Was Glutaraldehyde Used For?

Glutaraldehyde is a high-level disinfectant that was commonly used to disinfect heat-sensitive medical equipment like flexible endoscopes. A 2% alkaline solution was traditionally used in cold disinfection tanks, effective against:

• Vegetative bacteria

• Mycobacteria

• Viruses and fungi

• (With prolonged exposure) some bacterial spores

⚠️ So Why Was It Abandoned?

The UK's move away from glutaraldehyde reflects concerns about safety, compliance, efficacy — and prion transmission risk.

❗ 1. Occupational Safety Concerns (COSHH)

• Respiratory Sensitiser: Glutaraldehyde is a potent trigger for occupational asthma, rhinitis, and bronchial hyperreactivity.

• Skin Irritant: Direct contact causes dermatitis and chemical burns.

• Vapour Hazard: Even low vapour levels can cause symptoms, especially in poorly ventilated reprocessing areas.

• The HSE (Health & Safety Executive) and COSHH Regulations mandate tight control or substitution of such hazardous agents.

❌ 2. Process Control Failures in Manual Disinfection

• Manual soaking relies heavily on perfect technique — incorrect concentration, temperature, or soaking time = failure.

• No inactivation of biofilm or proteinaceous material if pre-cleaning is suboptimal.

• Residual glutaraldehyde can remain inside channels, causing chemical injury to patients.

• Inconsistent reproducibility made it non-compliant with HTM 01-06, BSG, and JAG standards.

🧬 3. Prion Transmission Concerns

One of the major reasons glutaraldehyde is now unsuitable is its ineffectiveness against prion proteins, such as abnormal PrP^Sc associated with:

• Variant CJD

• Iatrogenic CJD

• Other transmissible spongiform encephalopathies

🔎 Why It Matters:

• Prions are resistant to chemical disinfectants, including glutaraldehyde.

• Studies show glutaraldehyde may even fix prion proteins to instruments, making them harder to remove during cleaning.

• For any reusable instrument (including endoscopes) potentially exposed to high-infectivity tissues (e.g. tonsils, brain), validated prion inactivation methods must be used — typically involving:

  • Single-use instruments, or

  • Steam sterilisation at high temp/pressure after validated cleaning.

Hence, glutaraldehyde does not meet UK decontamination policy for instruments with any conceivable prion exposure.

✅ 4. Better Alternatives Are Now Standard

Modern NHS practice uses validated automated endoscope reprocessors (AERs) that use:

• Peracetic acid

• Hydrogen peroxide

• In some cases, ortho-phthalaldehyde (OPA)

These are:

• Safer for staff

• More effective against pathogens and biofilm

• Fully compatible with traceability, reproducibility, and audit

📚 UK Guidance Snapshot

Guidance	Position on Glutaraldehyde
HTM 01-06	Avoid glutaraldehyde; not suitable for safe reprocessing
COSHH/HSE	Hazardous; respiratory and skin sensitiser
BSG/JAG	Supports automated, validated systems
ACDP TSE Working Group	Prion risks: glutaraldehyde inadequate

💬 In FRCPath Exam Terms...

❝ Glutaraldehyde is no longer recommended for endoscope disinfection in the UK due to its health risks to staff, unreliability in manual processes, incompatibility with prion decontamination requirements, and the availability of safer validated alternatives. Current UK guidance favours automated reprocessors using agents like peracetic acid. ❞

🧠 FRCPath Part 2 Tip

Be ready to explain:

• Difference between high-level disinfection vs sterilisation

• What’s needed for TSE-prion risk mitigation

• How to respond to staff exposure complaints

• What you’d do if glutaraldehyde was found in use in an audit

📌 Final Takeaway

The shift away from glutaraldehyde reflects the NHS’s commitment to patient safety, staff wellbeing, and modern infection control standards. Its inability to neutralise prions, coupled with occupational hazard, makes it obsolete for today’s endoscopy and surgical environments.

✉️ Signup at FRCPathprep.com to stay ahead with more FRCPath Part 2 practice resources!