Thousands of NHS staff working in pathology departments across the UK are at risk from routine exposure to harmful levels of formaldehyde due to poor monitoring and control, according to an analysis of Freedom of Information requests published online in the journal Occupational & Environmental Medicine on June 9.
The analysis found that airborne levels of formaldehyde, a known carcinogen used as a tissue preservative, exceeded eight-hour European Union workplace limits in seven out of ten NHS pathology departments. The researchers called for urgent national regulatory intervention to protect the health of NHS employees working in these labs, noting there are 28,000 such workers in England alone.
The study highlighted that while the United States Environmental Protection Agency declared formaldehyde presents an "unreasonable risk of injury to human health" in 2024, and the EU introduced new binding workplace exposure limits for formaldehyde in 2021 (0.3 parts per million over eight hours), the UK maintained a higher limit of 2ppm after leaving the EU. Researchers sent Freedom of Information requests to all 122 NHS Trusts across England, Scotland, Wales, and Northern Ireland seeking data on monitoring frequency and caseloads from cell pathology departments during 2024-25. All trusts responded; most provided a full year's record covering over 1.7 million monitoring events.
Despite handling tens of thousands of surgical specimens annually—the average lab processed nearly 37,000—monitoring was infrequent: almost three-quarters measured airborne levels once a week or less. The EU long-term exposure limit was regularly exceeded at seventy percent of sites; only eleven percent conducting daily or more frequent checks did not regularly exceed it. While none surpassed current UK legal limits overall, nearly one-third recorded at least one instance above two parts per million within twelve months.
Researchers stated: "A substantial body of evidence demonstrates that formaldehyde is associated with myriad deleterious health effects at concentrations well below UK [workplace exposure levels]." They cited risks including respiratory and reproductive issues as well as increased cancer rates. They argued their findings have relevance beyond healthcare environments since many other industries also expose workers to formaldehyde.
The authors concluded: "Urgent national regulatory intervention is now warranted... This will require a combination of upgraded infrastructure, more regular personal exposure monitoring, better employee education... improved access to appropriate personal protective equipment... management accountability... and external oversight by the Health and Safety Executive." In an accompanying editorial, Professor Hans Kromhout and Dr. Martie van Tongeren acknowledged limitations with measurement methods but said, "Despite these limitations... it is obvious that exposure levels can be high... There are currently no common guidelines or standards for control and monitoring ... such guidelines are urgently needed." They advocated aligning UK workplace limits with those set by the EU.
