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Under the microscope: formaldehyde exposure in National Health Service pathology departments in the United Kingdom
Magdalena Plesa1, Richard L Yates2
1University of Liverpool Management School, Liverpool, UK mplesa@liverpool.ac.uk.
Objectives:
The US Environmental Protection Agency has determined that formaldehyde presents an 'unreasonable risk of injury to human health'. Occupational inhalation exposure is associated with short- and long-term damage to the respiratory, female reproductive and nervous systems, and is also carcinogenic. The European Union (EU) has recently introduced formaldehyde work exposure limits (WELs) lower (long-term 0.3 ppm; short-term 0.6 ppm) than those currently applied in the UK (long-term 2 ppm; short-term 2 ppm). UK regulation additionally requires exposure to carcinogens to be reduced to as low as is reasonably practicable. We evaluated formaldehyde airborne concentrations in National Health Service (NHS) cell pathology departments to assess the adequacy of exposure controls.
Methods:
Using the UK Freedom of Information Act (2000), we requested 12 months (2024-2025) of formaldehyde airborne monitoring data collected by cell pathology departments across 122 NHS Trusts in England (n=102), Scotland (n=10), Wales (n=6) and Northern Ireland (n=4). Results were evaluated empirically and using EN 689:2018 statistical methods to assess exposure variability, estimate upper-bound concentrations and determine the likelihood of adequate exposure control when benchmarked against EU WELs.
Results:
A total of 1 715 516 formaldehyde airborne monitoring results were disclosed by 117 NHS cell pathology departments. Monitoring was infrequent, with 73% of sites measuring formaldehyde airborne concentrations once weekly or less. The EU long-term WEL was exceeded regularly at 70% of sites (95th percentile >0.3 ppm), and the EU short-term WEL was exceeded regularly at 43% of sites (95th percentile >0.6 ppm). The 95th percentile upper tolerance limit (UTL95,70) exceeded the EU short-term WEL at 68% of sites. Only 11% and 17% of departments demonstrated frequent (once daily or more) formaldehyde airborne monitoring with 95th percentiles below the EU long- and short-term WELs, respectively.
Conclusions:
Formaldehyde exposure is infrequently monitored and inadequately controlled in NHS cell pathology departments.
