Association between humidifier disinfectant exposure during infancy and subsequent neuropsychiatric outcomes during childhood: a nation-wide cross-sectional study

A Study on the Preliminary Plan for Environmental Health in Seoul, Korea

In the Republic of Korea, the Environmental Health Act was amended in January 2021, making it mandatory for each local government to establish a plan for environmental health. Accordingly, the Seoul Metropolitan Government (SMG) must establish the Local Plan for Environmental Health (LPEH) to protect citizens' health from environmental hazards. The plan would support existing environmental health policies in Seoul to improve population health and achieve their goals. As a proof-of-concept to establish the LPEH, we developed a preliminary plan for environmental health in Seoul. We analyzed environmental health conditions of Seoul, identified driving conditions for execution of environmental health policies, set basic policy directions, and identified tasks needed to establish the preliminary plan. As a result, we established the vision and the goals of the preliminary plan. The vision is "a safe Seoul environment, healthy citizens". The strategies are "active monitoring of environmental health issues", "minimization of health damage and meticulous and systematic response", and "building a foundation for environmental health". To achieve the vision and the goals, we developed three strategies, eight tasks, and 25 sub-tasks. Under the preliminary plan we developed, we expect that SMG is able to protect citizens' health from threats of environmental hazards; improve environmental health conditions, especially in susceptible populations such as infants; and promote environmental justice.

Health Effects Associated With Humidifier Disinfectant Use: A Systematic Review for Exploration

BACKGROUND

It has been 10 years since the outbreak of lung disease caused by humidifier disinfectants in Korea, but the health effects have not yet been summarized. Therefore, this study aims to systematically examine the health effects of humidifier disinfectants that have been discovered so far.

METHODS

All literature with humidifier disinfectants and their representative components as the main words were collected based on the web, including PubMed, Research Information Sharing Service, and government publication reports. A total of 902 studies were searched, of which 196 were selected. They were divided into four groups: published human studies (group 1), published animal and cytotoxicology studies (group 2), technical reports (group 3), and gray literature (group 4).

RESULTS

Out of the 196 studies, 97 (49.5%) were published in peer-reviewed journals as original research. Group 1 consisted of 49 articles (50.5%), while group 2 consisted of 48 articles (49.5%). Overall, respiratory diseases such as humidifier disinfectant associated lung injury, interstitial lung disease, and asthma have a clear correlation, but other effects such as liver, heart, thymus, thyroid, fetal growth, metabolic abnormalities, and eyes are observed in toxicological experimental studies, but have not yet been identified in epidemiologic studies.

CONCLUSION

The current level of evidence does not completely rule out the effects of humidifier disinfectants on extrapulmonary disease. Based on the toxicological evidence so far, it is required to monitor the population of humidifier disinfectant exposure continuously to see if similar damage occurs.