Indoor air pollutant exposure and respiratory health risk assessment in urban healthcare facilities: a comparative study of public and private sectors

Abstract

Aim: Indoor air quality (IAQ) is a critical component of occupational health in hospitals, where healthcare workers face exposure to particulates and clinical chemical vapours. Prolonged exposure to these environments is linked to an increased incidence of chronic respiratory conditions. This study aimed to quantify the indoor concentrations of particulate matter (PM_2.5 and PM₁₀), formaldehyde (HCHO), and total volatile organic compounds (TVOCs) in public and private tertiary healthcare facilities in Benin City, Nigeria, and to evaluate the associated non−carcinogenic and carcinogenic health risks for personnel. Methods: IAQ was monitored in triplicate at high-occupancy sampling points over an eight-week period using handheld digital monitors. Health risks were assessed using hazard quotient (HQ) and incremental lifetime cancer risk (ILCR) models. Additionally, a structured questionnaire was administered to 152 hospital workers to correlate environmental data with self-reported respiratory symptoms. Results: The PM_2.5 and TVOC levels frequently exceeded the WHO guidelines in both facilities. The private facility exhibited alarming HCHO concentrations, particularly in the emergency (HQ=10.04) and laboratory (HQ=8.86) units, indicating risks up to ten times the safety threshold. Similarly, the ILCR exceeded the 1.0 × 10⁻⁴ threshold at the highest exposure site, reaching a peak of 1.49 × 10⁻⁴. Coughing (78.3%) was the most prevalent symptom. Notably, compared with workers in the private sector, workers in public hospitals faced significantly greater respiratory burdens, with an adjusted odds ratio (AOR) of 3.009 (95% CI: 1.277–7.088) for persistent cough and an AOR of 2.681 (95% CI: 1.093–6.578) for chest pain. Conclusions: Hospital indoor air poses severe toxicological and carcinogenic risks. Immediate implementation of advanced mechanical ventilation and specialized filtration is needed to safeguard healthcare personnel.

Keywords

indoor air quality / formaldehyde / respiratory health / occupational asthma / healthcare facilities

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