Indoor Exposure to Volatile Organic Compounds (Benzene, Toluene, Xylene, and Formaldehyde) and Associated Health Risk in Hotels of Hunan, China

Abstract

Background: Indoor air pollution caused by volatile organic compounds (VOCs) has garnered considerable attention, but its extent in hotel environments remains underexplored. This research was aimed at measuring the levels of VOCs (benzene, toluene, xylene, and formaldehyde) in hotels and evaluate their health risks using quantitative risk assessment methods, including lifetime carcinogenic risk (R) and noncarcinogenic hazard quotient (HQ). Method: Air samples were gathered from 79 hotels during the summer and winter of 2023. We analyzed the concentrations of four VOCs and conducted a descriptive analysis of the results. Spearman’s rank correlation and principal component analysis were utilized for statistical evaluation. US EPA guidelines were used to calculate both carcinogenic and noncarcinogenic risks, with uncertainty quantified through Monte Carlo simulation (10,000 iterations) to derive probabilistic risk distributions. Results: Formaldehyde was the most abundant compound found in hotels (median: 17 μg/m3, range: ND–130 μg/m3), and compliance rate reached 99.15% (GB 37488-2019 limit: 0.10 mg/m3). Principal component analysis revealed that adsorption/desorption processes, seasonal behaviors, emission sources, and humidity are the primary drivers of VOC variability in the hotel environment. The median HQ for the four VOCs was 5.25 × 10−2, all below 1. The median sum lifetime cancer risk for total VOCs was 2.45 × 10−5, and formaldehyde dominated the combined cancer risk. Conclusion: Formaldehyde is a primary pollutant in hotel air, and prolonged exposure (8 h/day, 6 days/week, and an exposure duration of 30 years) can pose a carcinogenic risk to humans. Improving ventilation and installing air purification systems are recommended to mitigate VOC exposures in the environments. However, this study has certain regional limitations in terms of geographical coverage, which may affect the generalizability of the findings.