1) Cohort development

 The Environment and Development of Children (EDC) cohort (The study for health effects of environmental hazardous chemicals on children’s growth and development)
- Fetuses are provided with not only nutrients and oxygen but also various chemicals from their mothers. 
- Hazardous effects can appear in the short terms such as in congenital deformity or in the long terms throughout children’s life courses. Thus, EDC cohort study aims to investigate the association between maternal and children’s exposure to environmental pollutants and children’s health during the course of development.
The Korean CHildren's ENvironmental health Study (Ko-CHENS) (The children’s environmental health birth cohort)
- Ko-CHENS recruits pregnant women residing in Korea from 2015 to 2019 and follows up their children from their fetal stages to early puberty for growth, neuro-cognitive development (e.g. ADHD), allergic diseases (e.g. atopic dermatitis), social skills, and emotional development in relation with environmental exposures.

The Korea Environmental Elderly Panel (KEEP) (The study for the effects of particulate matter in the elderly)
- Objective: To collect scientific evidence for the hazardous effects of indoor and outdoor particulate matter (PM)
- Study participants: 120 elderly people aged ≥60 years old who attend community welfare centers for the elderly
- Methods: 1) To develop an elderly panel data to assess individual level exposures to indoor and outdoor PM taking Korean life styles into account, 2) to assess the exposure level of PM by PM compositions, depending on individuals’ living spaces, and 3) to assess the effectiveness of various interventions to alleviate the health effects of indoor and outdoor PM exposures.

2) Environmental epidemiology studies

- To reveal the causal pathways of “external exposure → internal exposure (in utero) → response  → disease development” by integrative analysis of biological information (genome and epigenome), clinical information (phenome; in other words, collection of various clinical presentations such as respiratory and endocrine functions and neurocognitive development), and information on environmental exposures (exposome).

Air pollution
- To study the association between indoor and outdoor air pollution including particulate matter, ozone, carbon monoxide, and nitrogen dioxide and mortality and morbidity
Climate change 
- To study the health effects of extreme weather events such as heat waves, flood, and drought, and increase of infectious diseases which all can be linked with climate change
Endocrine disrupting chemicals (EDC)
- To study the health effects of EDC such as bisphenol A, phthalate, 3-PBA, and pyrethroids, which can disrupt normal endocrine functions when exposed to humans

3) Risk communication

Developing daily guidelines
*Particulate matter(PM) daily guidelines to reduce undesirable health effects of PM
1) Maintain active life styles under PM2.5 < 50μg/m3
2) PM masks are moderately recommended under PM2.5 50~100μg/m3 although individuals’ health status and discomfort from masks should be considered.
3) Masks are highly recommended and outdoor activities should be refrained under PM2.5 ≥ 100μg/m3
4) More strict control for PM is recommended for patients having asthma, chronic respiratory diseases, and cardiovascular diseases, and pregnant women.

Awareness and education
- Groups: pregnant women who visit public health centers, teachers and children in elementary schools and day care centers
- Format: 50 minutes lecture and 10 minutes questions and answers
- Contents: understanding and preventing the health effects of PM, understanding the health effects of endocrine disrupting chemicals
- Lecturers: residents and fellows of Department of Preventive Medicine, Seoul National University College of Medicine

4) International cooperation

- Professor Yun-Chul Hong wrote a report analyzing the children’s environmental health status in six countries in Asia Pacific (Cambodia, Indonesia, Myanmar, Philippines, Timor Leste, and Viet Nam) and suggesting the direction for children’s environmental health policies with the support from UNICEF. He also held the International Conference on Children's Health and the Environment (INCHES) on June 27-29th, 2018 in Seoul, and the international workshop “Consultation Workshop on Country Profiles on Children’s Health and Environment in East Asia and Pacific Region” on February 14-15th, 2019 in Seoul.
- Professor Yun-Chul Hong has advised on the environmental health policies in Asia Pacific as a WHO policy advisor, and continuously participating in international cooperation regarding air pollution policies as the chair of the Thematic Working Group on Air Quality under Asia-Pacific Regional Forum on Health and Environment. He also held the international workshop “Thematic Working Group on Air Quality” and the international symposium for “Climate, Environment, and Health in Asia Pacific” on June 19-21th, 2019 in Seoul.

UNEP(UN Environment Programme) 
- Professor Yun-Chul Hong wrote the report “Evidence-based solutions for air pollution in Asia Pacific” as the chair of the study group, with the support from and cooperation with UNEP and CCAC

AIRCAP(The Asian Initiative for Research on Climate and Air Pollution) 
- Professor Yun-Chul Hong is leading AIRCAP as the chair. AIRCAP is a research network formed by environmental epidemiologists specializing in air pollution and climate change in Asia Pacific regions.