Objectives The US Environmental Protection Agency has determined that formaldehyde presents an “unreasonable risk of injury to human health”. Occupational exposure studies demonstrate that chronic formaldehyde inhalation is associated with damage to the respiratory, female reproductive, and nervous systems, and is also carcinogenic. The UK long- and short-term work exposure limit (2ppm) is amongst the world’s highest and now diverges significantly from recently improved EU regulation (EU long-term exposure limit: 0.3ppm; EU short-term exposure limit: 0.6ppm). We sought to evaluate the formaldehyde monitoring data of NHS cell pathology departments and compare the extent of inhalation exposure to EU and UK work exposure limits.

Methods Using the Freedom of Information Act (2000), we requested 12 months of formaldehyde inhalation exposure monitoring data from n=121 NHS Trusts.

Results In total, 1,712,371 formaldehyde inhalation exposure monitoring events were disclosed by n=104 NHS Trusts on behalf of n=117 NHS cell pathology departments. Formaldehyde inhalation exposure is infrequently monitored (once weekly or less at 73% of sites) and EU work exposure limits are regularly breached (95th centile of exposure >0.3ppm at 70% of sites; 95th centile of exposure >0.6ppm at 44% of sites). Over a third (34%) of NHS cell pathology departments had exceeded the UK work exposure limit at least once in the preceding 12 months. Overall, only 11% of NHS cell pathology departments had at least once daily formaldehyde inhalation exposure monitoring demonstrating a 95th centile of exposure lower than the EU long-term work exposure limit.

Conclusions Urgent national regulatory intervention is warranted to improve the occupational hygiene of NHS cell pathology departments and protect the health of thousands of NHS employees.

What is already known A substantial body of occupational exposure data shows that formaldehyde inhalation is associated with myriad deleterious health effects on the respiratory, female reproductive, and nervous systems. It is also a human carcinogen. Pathology departments are amongst the riskiest occupational environments for formaldehyde inhalation exposure and therefore require a high standard of governance and infrastructure to adequately protect staff.

What this study adds We show that formaldehyde inhalation exposure in most NHS cell pathology departments is monitored infrequently and that EU work exposure limits are often breached. Our data raises concern for the health of thousands of NHS employees working in these environments.

How this study might affect research, practice, or policy Urgent national regulatory intervention is now warranted to improve the occupational hygiene of NHS cell pathology departments. This will require a combination of upgraded infrastructure, more regular personal exposure monitoring, better employee education on basic lab practice and chemical risk, improved access to appropriate personal protective equipment, management accountability for occupational health, and external oversight by the Health and Safety Executive.

The authors have declared no competing interest.

This study did not receive any funding

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Data disclosed under the Freedom of Information Act (2000) is publicly available.