Assessment of phthalate exposure at a fire site in Korean firefighters.

To determine phthalate exposure in 32 firefighters, the concentrations of urinary phthalate metabolites, immediately (exposure day) and three weeks (control day) after fire suppression, were compared. Mono-(2-ethyl-5-carboxypentyl) phthalate, mono-(2-ethyl-5-hydroxyhexyl) phthalate, mono-(2-ethyl-5-oxohexyl) phthalate, mono-n-butyl phthalate (MBP), mono-n-benzyl phthalate (MBzP), and total phthalates (∑phthalates) levels, and creatinine-adjusted levels of MBP, MBzP, and ∑phthalates were significantly higher on exposure day than on control day. Phthalate concentration was significantly higher in firefighters who performed the fire extinguishing tasks (geometric mean [GM], 149.9 µg/L) than in those who performed other tasks (GM 70.8 µg/L) (p = .012). The GM concentration of firefighters who were active ≤ 50 m from the fire was 119.0 µg/L, and 37.6 µg/L for those who were > 50 m away (p = .012). The GM concentration was significantly different (p = .039) in firefighters with subjective symptoms after fire suppression (151.9 µg/L) compared to those without symptoms (81.6 µg/L). This study showed that firefighters were exposed to phthalate.

Differences in salient beliefs associated with voluntary exercise training among South Korean firefighters before and after COVID-19.

BACKGROUND: Participating in voluntary exercise training is important to meet occupational requirements as well as firefighters' health and safety. The purpose of this study is to identify salient beliefs associated with voluntary exercise training among firefighters in the pandemic era by comparing outcomes with those from a previous elicitation study, which was carried out before the COVID-19 outbreak. METHODS: A total of 57 firefighters are recruited to participate in an elicitation study. Participants are requested to respond to six open-ended questions related to voluntary exercise training. Content analysis is used to create categories that combine similar factors in each belief. Beliefs mentioned by more than 30% of participants are used for comparison with the results of the previous research. RESULTS: "Improves my physical ability" (n = 44) and "cause injury" (n = 17) are identified as behavioral beliefs in the present study, whereas "makes me tired" and "takes too much time" were also elicited in Lee's study. Normative beliefs are "family members" (n = 45) and "colleagues" (n = 27) and these results are consistent with those in Lee's study. "Lack of time" (n = 28), "exercise facilities" (n = 19), and "COVID-19" (n = 19) are elicited as control beliefs in the present study, whereas "physical condition" (n = 21) and "exercise partners" (n = 14) were elicited as other control beliefs, and "COVID-19" was not mentioned in Lee's study. CONCLUSION: This study can contribute valuable information about salient beliefs associated with exercise training behavior among firefighters, particularly under pandemic conditions. Future researchers should develop tailored exercise training programs for firefighters based on current elicited beliefs.

Effects of the Omicron variant on perinatal outcomes in full-term neonates.

BACKGROUND: Research of coronavirus disease (COVID-19) effects on newborns is ongoing. But the research of specific variant's effects is none. This study analyzed the effects of the Omicron variant on the perinatal outcomes of full-term newborns during the Omicron wave period.  METHODS: Between December 2021 and April 2022, this study was conducted on all newborns who visited a single center. We investigated due to the Omicron maternal infection maternal pregnancy complications, delivery methods, birth week, Apgar scores, neonatal resuscitation program requirement, whether respiratory support was required until 12 h after childbirth, suspicious infectious status, and mortality depending on maternal Omicron infection. RESULTS: A total of 127 neonates were enrolled, and 12 were excluded based on exclusion criteria. Sixteen neonates were born to mothers with a history of Omicron COVID-19, and 99 were born to non-infectious mothers. All infected mothers became infected in the 3rd trimester. Of the 16 mothers, seven were symptomatic, and four met the isolation criteria, according to Korean guidelines. The birth weight of newborns to mothers with a history of COVID and those without was 2.958 ± 0.272 kg and 3.064 ± 0.461 kg (p = 0.049), respectively. The 5-min Apgar score at childbirth was 9.29 ± 0.756 and 9.78 ± 0.460 for neonates born to symptomatic and asymptomatic mothers (p = 0.019), respectively. When compared with or without maternal self-isolation, neonates requiring respiratory support 12 h after birth demonstrated a significant difference (p = 0.014; OR, 10.275). Additionally, the presence or absence of transient tachypnea of the newborn showed a significant value (p = 0.010; OR 11.929). CONCLUSIONS: Owing to Omicron COVID-19, newborns were born with lower birth weight, low 5-min Apgar scores, and required respiratory support until 12 h after birth.

Posttraumatic stress disorder symptoms and neurocognitive functioning in fire fighters: The mediating role of sleep problems and resilience.

BACKGROUND: Firefighters are often exposed to terrible and dangerous scenes due to their duties, and thus have a high risk of developing posttraumatic stress disorder(PTSD). The purpose of the study is to examine the relationship between PTSD symptoms, sleep problems, resilience and neurocognitive functioning of firefighters, and to identify the sequential mediating effects of sleep problems and resilience on the relationship between PTSD symptoms and neurocognitive functioning (especially psychomotor speed and processing speed). METHODS: Data were collected from 325 firefighters in eight fire departments in four regions of Korea. Subjects performed neurocognitive function tests and completed the following questionnaires: Primary Care PTSD Screening, Pittsburgh Sleep Quality Index-K and Connor-Davidson Resilience Scale-2. The correlation and dual mediation effects were analysed using SPSS 22.0 program and PROCESS macro 3.4 program. RESULTS: PTSD symptoms, neurocognitive functioning, sleep problems and resilience were significantly correlated with each other. In the sequential mediation model, the relationship between PTSD and psychomotor speed/processing speed was sequentially mediated by sleep problems and resilience after adjusting for demographic variables. CONCLUSIONS: The PTSD symptoms of firefighters were related to a sequential link between sleep problems, low resilience and decreased neurocognitive function. These findings could serve as a basis for more effective and integrated interventional strategies for facilitating better neurocognitive functioning in firefighters.

Rheumatoid arthritis in low-level toluene-exposed workers based on nationwide medical surveillance data in Korea.

BACKGROUND: There is growing evidence that exposure to organic solvents can play a role in the etiology of rheumatoid arthritis (RA). This prospective cohort study aimed to investigate the association between RA and toluene exposure. METHODS: The study cohort consisted of Korea Occupational Safety and Health Agency data from male workers exposed to toluene who had undergone a toluene-associated special medical examination at least once between January 1, 2000 and December 31, 2004 (n = 148,870). The morbidity from RA based on hospital admission records was estimated from 2000 to 2005 using National Health Insurance Claim Data. The standardized admission ratio (SAR) for RA was calculated with reference to the general population. Levels of urinary hippuric acid (HA), a metabolite of toluene, were measured and used for exposure assessment. RESULTS: Toluene-exposed workers were at an elevated risk of seropositive rheumatoid arthritis (ICD-10 code M05) with an SAR of 2.38 (95% confidence interval [CI]: 1.14-4.37) and other rheumatoid arthritis (M06) with an SAR of 1.22 (95% CI: 0.91-1.59). When data were stratified according to the duration of toluene exposure and by tertiles of urinary HA level, no significant difference was apparent. CONCLUSION: SARs of the toluene-exposed workers are higher than that of the general reference population, indicating that exposure to toluene may contribute to an increased risk of RA. Further studies of toluene-exposed workers with longer follow-up are needed.

The relationship between the pattern of shift work and sleep disturbances in Korean firefighters.

PURPOSE: Sleep disturbances are prevalent in firefighters, but the relationship between patterns of shift work and sleep disturbances has not yet been investigated. Here, this relationship has been evaluated in Korean firefighters. METHODS: A cross-sectional study was conducted using an online questionnaire, which captured demographic, psychosocial and work-related characteristics. Sleep disturbance was assessed using the insomnia severity index (ISI). The relationship between insomnia and work-related factors (including type of shift work and the frequency of emergency events and off-duty work which means overtime work on off days) was analyzed. RESULTS: A total of 9810 firefighters completed the survey, representing approximately 21.5% of all Korean firefighters; data from 9738 subjects were included in the analysis. All firefighter roles were significantly associated with insomnia; the odds ratio (OR) was 2.456 (95% confidence interval [CI] 1.461-4.128) for fire suppression and 1.871 (95% CI 1.105-3.167) for the emergency medical services and rescue. However, the pattern of shift work did not show a statistically significant relationship. The OR increased along with the frequency of emergency events and off-duty work (p value for trend < 0.05). CONCLUSIONS: This study found a significant association between the frequency of emergency and off-duty work and insomnia in Korean firefighters, whereas the pattern of shift work showed no significant relationship. Therefore, measures to reduce the frequency of emergency and off-duty work are required to prevent sleep disturbances in firefighters.

Cancer mortality in Korean workers occupationally exposed to methanol: a cohort study.

PURPOSE: Recently, the international agency for research on cancer recommended that methanol should be recognized as a medium-priority, human cancer risk. Therefore, we performed an epidemiological study to evaluate the relationship between methanol exposure and the cancer mortality of Korean workers occupationally exposed to methanol. METHODS: The study cohort was composed of methanol-exposed 25,218 male workers, data on whom were available from the Korea Occupational Safety and Health Agency; all participants underwent methanol-associated medical check-ups at least once between January 2000 and December 2004. The durations of methanol exposure were categorized as < 10, 10-20, and ≥ 20 years. Workplace methanol exposure levels for each worker were divided into three grades. We compared their standardized cancer mortality rates (SMRs) to those of the general population. Intra-cohort hazard ratios were estimated using a Cox's proportional hazards model. RESULTS: We found no positive association between methanol exposure and cancer mortality. In terms of all cancer mortality, methanol-exposed workers exhibited significantly lower SMRs than the general population. In terms of other cancer mortality, no significant difference or trend was evident as a function of duration of methanol exposure. CONCLUSIONS: Although we found no significant correlation between methanol exposure and cancer mortality, we believe the work is meaningful; this is the first, large-scale, human epidemiological study. The carcinogenic potential of methanol remains an open question, and studies with longer-term follow-up periods are needed.

Occupational exposure to crystalline silica and gastric cancer: a systematic review and meta-analysis.

Crystalline silica is a widely used industrial material that is readily available worldwide, and is one of the most common types of particulate mineral pollutants. It has been classified as a group 1 human carcinogen of the respiratory system; however, whether it is linked to gastric cancer remains uncertain. We conducted a systemic review and meta-analyses to search for evidence of the relationship between gastric cancer and occupational exposure to crystalline silica. We searched for articles on occupations involving silica exposure and gastric cancer studies up to December 2014. Pooled-risk estimates of the association between occupational crystalline silica exposure and risk of gastric cancer were calculated by a random effects model. Metaregression analyses of industry type and histological confirmation status, study design and industrial subgroup analyses were performed. 29 articles, including 9 case-control and 20 cohort studies, were analysed. The overall summary effects size was 1.25 (95% CI 1.18 to 1.34) for the association of occupational silica exposure with gastric cancer. Both heterogeneity and publication bias were partially attenuated after subgroup analyses. Heterogeneity of studies was attenuated after metaregression by industry. Higher overall effects were observed in the mining and foundry industries. We found a significant relationship between occupational crystalline silica exposure and gastric cancer. Our results were strengthened by various subgroup analyses and, considering the biological plausibility of our premise, further studies are required to better understand this association.

Central nervous system diseases of organic solvents exposed workers based on nationwide medical surveillance-data in Korea.

BACKGROUND: New light is being shed on the relationship between chronic neurotoxicity of the central nervous system (CNS) and exposure to low-level organic solvents (OS). However, there are few longitudinal studies with a large sample size. METHODS: A cohort of OS-exposed male workers was selected who had undergone an OS-associated specialized medical check-up at least once between 2000 and 2004 in Korea. The standardized admission ratios (SAR) for CNS diseases were calculated with reference to the Korean adult male population. Adjusted relative risks (ARR) were also estimated in comparison to noise-exposed male workers. RESULTS: There were 238,574 OS-exposed workers, yielding 954,772 person-years of exposure. OS-exposed workers were at elevated risk of "other extrapyramidal and movement disorders" (G25) with a SAR = 2.95 (95% CI: 1.41-5.42) and "systemic atrophies primarily affecting the CNS" (G10-G13) SAR = 2.08 (95% CI: 1.03-3.74). There were no significant differences between the OS-exposed workers and noise-exposed workers. CONCLUSIONS: A limited number of CNS diseases identified through hospital admissions data and short observation periods reduced statistical power to determine effect size. OS exposure was positively associated with "other extrapyramidal and movement disorder and systemic atrophies primarily affecting the CNS.

Characteristics of Workplace Injuries among Nineteen Thousand Korean Firefighters.

To determine the actual firefighter injury statistics in Korea, we conducted a survey on the nature of on-duty injuries among all male firefighters in Korea. We distributed questionnaires to all Korean male firefighters via email, and data from the 19,119 workers that responded were used for data analysis. The job types were categorized into fire suppression, emergency medical service (EMS) and officers. As estimated of age standardized injury prevalence per one thousand workers, 354 fire extinguishing personnel, 533 EMS workers, and 228 officers experienced one or more injuries during the previous 12 months. The odds ratio (95% confidence interval) of injuries was 1.86 (1.61-2.15) for fire suppression and 2.93 (2.51-3.42) for EMS personnel compared to officers after adjusting for age, marital status, smoking habit and career period. Age standardized absence days from work due to injuries per one thousand workers were 1,120, 1,337, and 676 for fire suppression, EMS and officers, respectively. Car accident (24.5%) was the most common cause and wound (42.3%) was the most common type of injuries. Our nationwide representative study showed that fire suppression and EMS workers are at greater risk of on-duty injuries compared to officers. We observed different injury characteristics compared to those reported in other countries.

Epidemiologic characteristics of compensated occupational lung cancers among Korean workers.

An understanding of the characteristics of occupational lung cancer is important to establish policies that prevent carcinogen exposure and to compensate workers exposed to lung carcinogens. This study analyzed the characteristics of occupational lung cancers in workers who were compensated under the Industrial Accident Compensation Insurance Law between 1994 and 2011. A total of 179 occupational lung cancers were compensated. The main carcinogenic exposure was asbestos, followed by crystalline silica and hexavalent chromium. The mean exposure duration and latency were 19.8 and 23.2 yr. The most common industry was manufacturing, followed by construction and transportation. The most common occupation was maintenance and repair, followed by foundry work, welding, painting, and spinning or weaving. Although asbestos was predominant carcinogen, the proportion of these cases was relatively low compared to other developed countries. Proper surveillance system is needed to monitor occupational lung cancer and improve prevention measures.

Improving Cardiorespiratory and Muscular Function of Korean Firefighters: A Kinect-Based Mixed Reality Device Exercise Intervention Randomized Control Trial.

OBJECTIVE: This study addresses declining physical fitness among Korean firefighters due to a low exercise participation rate caused by the absence of exercise instructors. The research explores Virtual Mate (VM), a Kinect-based mixed reality device, as a potential solution, but its capacity to replace training instructors in enhancing physical fitness remains uncertain. METHODS: Twenty Korean male firefighters were divided into two groups: the exercise group received an 8-week intervention using VM, while the control group maintained regular physical activity. Cardiopulmonary function and muscle function were measured. RESULTS: After 8 weeks, the exercise group demonstrated a significant improvement in VO 2peak . Furthermore, there were notable enhancements in the strength and endurance of most knee, shoulder, and trunk flexors and extensors. CONCLUSIONS: Integrating VM into an exercise program can effectively improve cardiorespiratory and muscular function in Korean firefighters.

Work-related infectious diseases among Korean workers compensated under the Industrial Accident Compensation Insurance Law, 2006-2011.

BACKGROUND: Korea has no surveillance system for work-related infectious disease. However, these diseases are compensated by the Korea Workers' Compensation & Welfare Service (KCOMWEL). OBJECTIVES: To understand the nature and distribution of compensated occupational infectious diseases in Korea. METHODS: We used the KCOMWEL electronic database to analyze compensated cases of work-related occupational infectious disease. We reviewed and confirmed diagnoses excluding denied claims, secondary infections, dermatoid diseases, duplicated cases and those with missing information. We calculated the distribution of work-related infectious disease in Korea by occupation, calendar year, gender, age, and employment duration, as well as the annual compensated claim rates (per million). RESULTS: We included 1,062 compensated cases of work-related infectious disease. The most common was scrub typhus (n = 567, 53.4%), followed by tuberculosis (n = 227, 21.4%), viral hepatitis (n = 55, 5.2%), and viral influenza (n = 53, 5.0%). A sudden increase in scrub typhus was observed in 2009. Unskilled laborers, including short-term contract workers in public sectors, were most commonly affected by these diseases, followed by health care professionals. CONCLUSIONS: Workers employed in forestry care in the public sectors and in hospitals were most vulnerable to infections. Proper surveillance systems to monitor infectious diseases among vulnerable working groups and improved prevention measures are needed.

Association Between Parental BMI and Offspring's Blood Pressure by Mediation Analysis: A Study Using Data From the Korean National Health and Nutrition Examination Survey.

OBJECTIVES: This study analyzed the relationship between parental body mass index (BMI; BMI_p) and hypertension in their adolescent offspring (HTN_a), focusing on the mediating effect of adolescents' BMI (BMI_a). METHODS: Utilizing data from the Korea National Health and Nutrition Examination Survey, including participants aged 12-18, we conducted a mediation analysis while controlling for confounding factors such as age, sex, physical activity, dietary habits, household income quartile, and parents' alcohol and smoking habits. RESULTS: The study included a total of 5731 participants, of whom 3381 and 5455 participants had data on fathers' and mothers' BMI, respectively. For adolescent systolic blood pressure (SBP_a), the father's BMI (BMI_f) had a significant total effect (ß, 0.23; 95% confidence interval [CI], 0.12 to 0.34) and average controlled mediated effect (ACME) (ß, 0.27; 95% CI, 0.23 to 0.32), but the average direct effect (ADE) was not significant. The mother's BMI (BMI_m) had a significant total effect (ß, 0.17; 95% CI, 0.09 to 0.25), ACME (ß, 0.25; 95% CI, 0.22 to 0.28) and ADE (ß, -0.08; 95% CI, -0.16 to 0.00). For adolescent diastolic blood pressure, both BMI_f and BMI_m had significant ACMEs (ß, 0.10; 95% CI, 0.08 to 0.12 and ß, 0.09; 95% CI, 0.07 to 0.12, respectively), BMI_m had a significant ADE (ß, -0.09; 95% CI, -0.16 to -0.02) but BMI_f had an insignificant ADE and total effect. CONCLUSIONS: The study found that parental BMI had a significant effect on SBP_a, mediated through BMI_a. Therefore, a high BMI in parents could be a risk factor, mediated through BMI_a, for systolic hypertension in adolescents, necessitating appropriate management.

Validating a Korean Version of the Single-Item Burnout Measure for Evaluating Burnout Among Doctors.

OBJECTIVE: It is essential to measure the effect of burnout on doctors because burnout can affect doctors' mental health as well as the functioning of medical practice. This study aims to validate a Korean version of the single-item burnout measure (SIBM), which was developed to quickly measure the level of burnout among doctors. METHODS: Through an online survey, a self-report questionnaire was administered to 324 public health doctors in Korea. The Korean version of the SIBM was validated against the Maslach Burnout Inventory-General Survey (MBI-GS), the Patient Health Questionnaire-9 (PHQ-9), the Generalized Anxiety Disorder-7 (GAD-7) screening tool, the Perceived Stress Scale (PSS), and the Vaccination Attitudes Examination (VAX) scale. Pearson correlation coefficients and analysis of variance (ANOVA) were used to determine the association between the SIBM and other scales. ANOVA was additionally used to determine the associations between the subscales of the MBI-GS and those of the SIBM. RESULTS: The correlation coefficient between the SIBM and the MBI-GS, PHQ-9, GAD-7, and PSS was positive (p<0.01), and the correlation coefficient between the SIBM and the VAX scale was not significant. Therefore, convergent and discriminant validity was verified. Exhaustion and cynicism, which were correlated with the SIBM, with r2=0.43 (p<0.01) and 0.48 (p<0.01), yielded R2 scores of 0.27 (p<0.01) and 0.20 (p<0.01) in ANOVA. CONCLUSION: The Korean version of the SIBM is an appropriate screening tool for burnout. It can be evaluated in a short time, thereby enhancing continuous follow-up observations and response rates to burnout.

The Effect of Prior Mental Health on Persistent Physical Symptoms after Exposure to a Chemical Disaster.

A styrene monomer (SM) oil vapor leak occurred at a chemical plant in Seosan, South Korea on 17 May 2019. A bad odor developed, and many residents complained of various symptoms and visited nearby medical institutions. We analyzed the demographic and clinical characteristics of patients treated at local hospitals and clinics for symptoms related to SM exposure, and identified factors affecting symptom persistence in any organ. Data were collected by the main Seosan office, and 1201 (33.0%) subjects agreed to participate in this study. We used the Assessment of Chemical Exposure toolkit of the Agency for Toxic Substances and Disease Registry. Logistic regression was performed to determine whether mental health symptoms prior to the accident were risk factors for symptom persistence. The strongest risk factor for persistence of at least one symptom in any organ was a preexisting mental health symptom (odds ratio [OR] = 5.47, 95% confidence interval [CI]: 2.57-11.65). Persistent symptoms of the nervous (OR = 1.54), musculoskeletal (OR = 1.92), and gastrointestinal (OR = 1.45) systems were observed. Prior mental health symptoms are risk factors for persistent physical symptoms after a chemical disaster. After a disaster, management of individuals with preaccident mental symptoms or disease is needed.

Development of the Korean Firefighter Performance Battery: Job-Related Physical Fitness Assessment.

OBJECTIVE: The Candidate Physical Capability Test (CPAT) has been used in many countries to assess the fitness levels of firefighters, but it requires a special facility with a space of at least 900 square m 2 and expensive equipment. Because it can be difficult to have both money and space at smaller gas stations, we have developed the Korean Firefighter Performance Battery (KFPB). METHODS: To verify the validity and reliability of the developed KFPB, this study consists of three parts, a validation test, reliability test, and evaluation criterion. RESULTS: As a result of the analysis, the KFPB met all of the criteria as a valid evaluation. Furthermore, the KFPB seems to compensate for the shortcomings of CPAT. CONCLUSIONS: In locations where the CPAT is difficult to administer, the KFPB is expected to be used as a firefighting job-related physical fitness evaluation.

Cancer morbidity of professional emergency responders in Korea.

BACKGROUND: Many professional emergency responders (ERs) who belong to the Korean National Emergency Management Agency (NEMA) have been cross-trained and serve multiple roles. As such, firefighters and other ERs in Korea are exposed to similar occupational hazards. This study was conducted to estimate cancer morbidity in male ERs and compare that with Korean men. METHODS: The cohort was comprised of 33,416 male ERs working between 1980 and 2007, who were alive on December 31, 1995. Work histories were merged with the Korea National Central Cancer Registry (KNCCR) to assess cancer morbidity between 1996 and 2007. Standardized incidence ratios (SIRs) with reference to Korean men were analyzed. RESULTS: SIRs with reference to national cancer rates were not significantly decreased for overall cancer (SIR = 0.97, 95% CI = 0.90-1.08) in all ERs. However, colorectal (SIR = 1.35, 95% CI = 1.07-1.67), kidney (SIR = 1.59, 95% CI = 1.00-2.41), and bladder (SIR = 1.77, 95% CI = 1.08-2.73) cancer, and non-Hodgkin's lymphoma (SIR = 1.81, 95% CI = 1.12-2.76) morbidities were significantly increased among all ERs. In firefighters, significantly increased cancer types were as same as those of all ERs. In non-firefighter ERs, colorectal (SIR = 2.51, 95% CI = 1.20-4.61) and bone and articular cartilage cancers (SIR = 9.53, 95% CI = 1.07-34.41) were significantly higher than those of Korean men. CONCLUSIONS: Korean firefighters showed excess morbidity in several cancer types, including colorectal and urologic cancers, and non-Hodgkin's lymphoma, demonstrating similar trends to previous studies for firefighters conducted in other countries. Increased incidence in these cancer types suggests occupational exposure to carcinogens and shift work.

Biological monitoring for exposure assessment of volatile organic compounds by Korean firefighters at the fire site.

The VOCs and metabolites in urine for exposed VOCs were evaluated for firefighters who participated in the actual fire fighting to determine whether firefighters were exposed to hazardous chemicals, which is the basic data on cancer risk of firefighters. When the fire extinguishing time is long, the concentration of benzene, PHEMA, and toluene among VOCs and metabolites in the case of fire suppression, rescue, and fire investigation work, which is estimated that the exposure of hazardous substances generated from the fire site at the time of fire suppression was large, significantly increased. In the case where the number of urination is 2 or less, the concentration of TZCA, toluene, and benzene among VOCs and metabolites was significantly increased compared to the number of urinating more than 2 times. In the concentration of VOCs and metabolites in urine corrected with creatinine, the concentrations of toluene and PHEMA in urine were significantly higher. The concentration of PHEMA in urine was higher in the group who participated in the fire suppression for more than 11 hours (long time) than the group who participated in the fire suppression for a short time.