Skip Navigation
Skip to contents

Epidemiol Health : Epidemiology and Health

OPEN ACCESS
SEARCH
Search

Search

Page Path
HOME > Search
2 "Kiook Baek"
Filter
Filter
Article category
Keywords
Publication year
Authors
Funded articles
Epidemiologic Investigation
An outbreak of neurologic symptoms among patients exposed to an unknown stench in a high school near an industrial complex: an epidemiological investigation
Kiook Baek, Seongmin Jo, Chulyong Park, Joon Sakong
Epidemiol Health. 2022;44:e2022105.   Published online November 9, 2022
DOI: https://doi.org/10.4178/epih.e2022105
  • 2,951 View
  • 95 Download
AbstractAbstract AbstractSummary PDFSupplementary Material
Abstract
OBJECTIVES
Seven students at a high school in Korea visited the emergency room with non-specific neurological symptoms after a stench was noticed during a school entrance ceremony. In relation to this incident, 105 patients visited medical institutions over 5 days. A team of environmental and epidemiological experts was assembled to investigate the incident.
METHODS
Our team of experts participated in the investigation 1 month post-incident. Previously, only air samples had been analyzed. We received results of air samples analyzed by other investigators, medical records of some students, and data from police interviews of patients. Additional investigation and interviews were conducted, and the events were reconstructed in spatial and temporal order.
RESULTS
A cluster of patients was observed on the south side and parts of the north side of the upper floor. A stench like that reported during the incident had been noticed for about 2 years near the school. Students consistently described a similar stench occurring frequently in the vicinity of the school. According to student statements, the odor mainly resembled something burning. The carboxyhemoglobin levels of some students were observed to be >1.5%.
CONCLUSIONS
In the investigation, 2 suspected sources were identified: a science room storing chemicals downstairs from the auditorium and various industrial facilities near the school. Combining the scattered evidence, we considered a toxic puff of gas, perhaps from brief incineration or leakage in a specific area, to be the likely cause of the incident. We describe our approach and the limitations encountered during the investigation.
Summary
Korean summary
본 논문은 일개 고등학교에서 원인미상의 악취와 함께 100명 이상의 환자가 발생한 사건에 대한 조사과정을 담은 문헌이다. 본 연구진은 사건 발생 후 약 1달 후에 조사진에 합류하였으며, 발생 당시 환자 분포 점지도 작성, 인근 지역 사업장 및 악취발생 장소 점지도 작성, 사건 전후 시계열적 사건분석, 기상자료, 관계자 인터뷰 자료 분석 등의 역학적 기법을 동원하여 원인을 인근 지역에서 발생한 퍼프 가스의 유입으로 추정하였다. 본 사건의 원인은 결국 미제로 종결되었지만 추후 유사 사례 발생시 본 조사의 방법론을 참고할 수 있을 것이며, 의료진의 조기 개입을 수행하지 못함으로 인한 초기 상세 인터뷰 자료 확보, 생체 시료 수집 등이 이루어지지 못한 본 조사 과정의 한계점을 반면교사로 삼을 수 있을 것이다.
Key Message
This paper presents an investigation of an outbreak of over 100 patients experiencing an unexplained odor in a high school. The research team utilized epidemiological methods, including dot mapping, temporal analysis of events, and interview data analysis. The source of the odor was estimated to be the inflow of puff gas from surrounding areas. Although the toxic puff gas discharge facility was not identified, sharing the experience from this investigation could help with future investigations of similar incidents.
Systematic Review
Systematic review and meta-analysis of cancer risks in relation to environmental waste incinerator emissions: a meta-analysis of case-control and cohort studies
Kiook Baek, Jong-Tae Park, Kyeongmin Kwak
Epidemiol Health. 2022;44:e2022070.   Published online September 1, 2022
DOI: https://doi.org/10.4178/epih.e2022070
  • 4,366 View
  • 210 Download
  • 1 Web of Science
AbstractAbstract AbstractSummary PDFSupplementary Material
Abstract
OBJECTIVES
Various toxic substances can be generated from incinerators, exposing nearby residents, and epidemiological studies have shown wide variations in risk estimates for cancer risk in populations living close to incinerators.
METHODS
Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, a literature search and systematic review were conducted to identify studies conducted on general populations exposed to environmental incinerator emissions and cancer outcomes. Meta-analysis was performed according to the cancer types for which 2 or more studies were reported. Subgroup analysis was done for sex, the exposure estimation method, the study period, and the type of outcome.
RESULTS
Eleven studies were found for the qualitative review and meta-analysis. Seven studies had a case-control design, and 4 had a cohort design. The pooled effect size was not significant for breast, colorectal, liver, lung, lymphohematopoietic, stomach, bladder, central nervous system, and laryngeal cancers, non-Hodgkin lymphoma, sarcoma, leukemia, and all cancers. In the subgroup analysis, the pooled effect size of laryngeal cancer in females was 1.82 (95% confidence interval, 1.10 to 3.01), although only 2 studies were identified.
CONCLUSIONS
The meta-analysis did not provide evidence of an increased risk for any cancer among populations living near waste incinerators, except for laryngeal cancer in females. However, since relatively few studies were reviewed and some cancer types showed significant increases in individual studies, this evidence needs to be updated regularly.
Summary
Korean summary
본 연구에서는 현재까지 소각장 인근 주민들의 암 위험도에 대해 보고된 환자-대조군 연구 및 코호트 연구를 체계적 문헌고찰과 메타분석법을 활용하여 분석하였다. 총 11개의 문헌에서 보고한 암 위험도를 암종별로 분석한 결과 소각장 인근 거주로 인한 암 위험도 상승이 유의하게 상승한 암종은 없었다. 세부 그룹 분석에서 여성의 후두암이 비록 단 2개 문헌에서만 보고하고 있었지만 유의한 상승을 보였다. 본 연구는 현재까지 논란이 많은 소각장 인근 거주와 암 발생 위험도의 증가에 대해 관찰연구로서 생태학적 연구를 배제하고 비교적 역학적 증거로서 가치가 높은 연구방법인 환자-대조군 연구와 코호트 연구를 고찰한 의의가 있으며, 본 연구의 방법론을 활용하면 추후 같은 주제의 증거를 지속적으로 갱신하여 종합할 수 있으리라 기대한다.
Key Message
This meta-analysis showed a lack of evidence of elevated risk of specific cancers after pooling the effect sizes by cancer type, except for laryngeal cancer in women. However, due to the small number of included studies, the evidence needs to be monitored and updated on a regular basis in the future.

Epidemiol Health : Epidemiology and Health