Association between humidifier disinfectant use and development of lung cancer: A nested case-cohort study

Objective: The outbreak of lung disease among humidifier disinfectants (HDs) users lead to the identification of humidifier disinfectants-associated lung injury (HDLI) cases. Subsequent research highlighted the respiratory health risks associated HDs but the connection to lung cancer remained uncertain. To assess the risk of lung cancer development among individuals exposed to HDs and to investigate the characteristics of HDs exposure influencing the occurrence of lung cancer. Materials and methods: A cohort study was conducted using the national database, encompassing 7343 claimants exposed to HDs. The study focused on 195 confirmed lung cancer cases, employing the standardized incidence ratio (SIR) for comparisons with the general population, and the odds ratio (OR) using propensity score matching for internal comparisons. Results: The study found a significantly higher incidence of lung cancer among individuals exposed to HDs compared to the general Korean population, with elevated SIRs observed in both men and women (SIR = 3.43, 95 % CI = 2.81–4.13 for men; SIR = 11.19, 95 % CI = 8.95–13.82 for women). In the propensity score-matched case-control design, a longer duration of HDs use was associated with an increased risk of lung cancer (OR = 2.48, 95 % CI = 1.35–4.56 for using HDs for more than 49 months and OR = 1.02, 95 % CI = 1.01 – 1.03 for every one month). Conclusion: The findings suggest a potential association between HDs exposure and an increased risk of lung cancer.