Exposure to biocides and their potential exposure sources among adults: A nationwide population-based study in South Korea.

Biocides are present in personal care (including preservatives or antibacterials), pest control, and disinfectant products (including non-agricultural insecticides, fungicides, and disinfectants), and their long-term exposure may induce adverse health effects in humans. Therefore, in this study, we assessed the exposure levels and major exposure predictors of biocides among nationally representative Korean adults. The target group included adults (≥19 years) participating in the Korean National Environmental Health Survey (KoNEHS) 2015-2020. We employed survey-weighted multiple regression analysis and conditional inference trees analysis to assess the associations between demographic characteristics, behavioral sources (including personal care product use, pesticide use, and dietary patterns), and urinary levels of phenol (triclosan [TCS]), parabens (methyl paraben [MP], ethyl paraben [EP], propyl paraben [PP], and butyl paraben [BP]), and the pyrethroid insecticide metabolite (3-phenoxybenzoic acid [3-PBA]). Urinary EP, BP, and 3-PBA levels were higher in South Korean adults compared with those in Western countries. Major exposure predictors for MP, EP, and PP included the use of personal care products such as sunscreen, makeup, and hair care products in KoNEHS 2018-2020. Major exposure predictors for TCS and BP were vegetable consumption, and those for 3-PBA were mosquitocide use during summer in KoNEHS 2018-2020. However, these predictors were not observed in KoNEHS 2015-2017. Collectively, our findings suggest that biocide exposure predictors vary according to changes in product use and diet habits of individuals. Therefore, developing strategies to mitigate biocide exposure based on the demographic and behavioral characteristics of the general population is imperative.

Relationship between the use of hair products and urine benzophenone-3: the Korean National Environmental Health Survey (KoNEHS) cycle 4.

Background: Benzophenone-3 is a type of ketone with 2 benzene rings attached to a carbonyl group (C=O) and one benzene ring attached to a hydroxyl group (-OH). As an endocrine-disrupting chemical, benzophenone-3 is known to be associated with reproductive, developmental, thyroid, and endocrine toxicities. Benzophenone-3 is commonly used in hair products, cosmetics, and ultraviolet (UV) filters because of its characteristic property to absorb UV light. This study aims to investigate the association between the use of hair products and urine benzophenone-3 using the data from the Korean National Environmental Health Survey (KoNEHS) cycle 4 (2018-2020), which represents the Korean population. Methods: Using the KoNEHS cycle 4 survey, the data of 3,796 adults aged ≥ 19 years were analyzed. Based on the 75th percentile concentration of urine benzophenone-3, the participants were divided into the low- and high-concentration groups. Chi-square test was conducted to analyze the association of urine benzophenone-3 with distribution of general characteristics, use of personal care products, consumption of marine foods, and use of plastic products as the variable. Logistic regression analysis was conducted to calculate odds ratios (ORs) for the high-concentration group of urine benzophenone-3 based on the use of hair products. Results: Women with < 6 times or ≥ 6 times of hair product usage had significantly higher adjusted ORs compared to those who did not use hair products. The calculated ORs were 1.24 (95% confidence interval [CI]: 1.12-1.38) for women with < 6 times of usage and 1.54 (95% CI: 1.33-1.79) for women with ≥ 6 times of usage. Conclusions: This study revealed the association between the use of hair products and the concentration of urine benzophenone-3 in the general Korean population.

Relationship between crustacean consumption and serum perfluoroalkyl substances (PFAS): the Korean National Environmental Health Survey (KoNEHS) cycle 4.

Background: Perfluoroalkyl substances (PFASs) are non-aromatic organic compounds, whose hydrogen atoms in the carbon chain substituted by fluorine atoms. PFASs exhibit developmental toxicity, carcinogenicity, hepatotoxicity, reproductive toxicity, immunotoxicity, and hormone toxicity. PFASs are used in the production of disposable food packages, aircraft and automobile devices, cooking utensils, outdoor gear, furniture and carpets, aqueous film forming foam (AFFF), cables and wires, electronics, and semiconductors. This study aimed to determine the association between crustacean consumption and serum PFASs. Methods: Adult participants (2,993) aged ≥ 19 years were extracted from the 4th cycle data of the Korean National Environmental Health Survey (KoNEHS). Based on the 50th percentile concentrations of serum PFASs, participants were divided into the low-concentration group (LC) and the high-concentration group (HC). General characteristics, dietary factors, coated product usage, and personal care product usage, an independent t-test and χ2 test were analyzed. The odds ratio (OR) of serum PFAS concentration against crustacean consumption was estimated via logistic regression analysis adjusting for general characteristics, dietary factors, coated product usage, and personal care product usage. Results: The OR for the HC of serum PFASs was higher in individuals with ≥once a week crustacean consumption than in those with < once a week crustacean consumption. Estimated ORs were perfluorohexanesulfonic acid 2.15 (95% confidence interval [CI]: 1.53-3.02), perfluorononanoic acid (PFNA) 1.23 (95% CI: 1.07-1.41), and perfluorodecanoic acid (PFDeA) 1.42 (95% CI: 1.17-1.74) in males, and perfluorooctanoic acid 1.48 (95% CI: 1.19-1.84), perfluorooctanesulfonic acid 1.39 (95% CI: 1.27-1.52), PFNA 1.70 (95% CI: 1.29-2.26) and PFDeA 1.43 (95% CI: 1.32-1.54) in females. Conclusions: This study revealed the association between the crustacean consumption and concentrations of serum PFASs in general Korean population.

Exposure to biocides and its association with atopic dermatitis among children and adolescents: A population-based cross-sectional study in South Korea.

BACKGROUND: Biocides have emerged as a contributor to the rising cases of atopic dermatitis among children and adolescents. Previous animal studies suggested that phenols, parabens, and pyrethroid insecticides present in these products might play a role in atopic dermatitis. However, there's limited epidemiological evidence confirming the individual or combined effects of exposure to these chemicals on atopic dermatitis in young populations. This study aimed to investigate the association between phenol, paraben, and pyrethroid metabolite levels in urine and atopic dermatitis among Korean children and adolescents METHODS: We analyzed 556 preschool children (3-5 years), 701 schoolchildren (6-11 years), and 731 adolescents (12-17 years) enrolled in the 4th Korean National Environmental Health Survey (KoNEHS) (2018-2020). We used logistic regression and Bayesian kernel machine regression to evaluate the association between atopic dermatitis and individual or mixed exposure to urinary triclosan (TCS), parabens (methylparaben, ethylparaben, propylparaben, and butylparaben), and 3-phenoxybenzoic acid (3-PBA) levels. RESULTS: Urinary TCS levels were positively associated with atopic dermatitis in schoolchildren. When stratified by sex, male schoolchildren exhibited an increasing prevalence of atopic dermatitis as their urinary TCS and 3-PBA levels increased. The combined effect of biocide mixtures on atopic dermatitis was also significantly increased in male schoolchildren, with TCS as the main contributor. CONCLUSIONS: These study findings suggest that biocides at levels found in Korean children and adolescents affect atopic dermatitis.

Environment-wide association study to identify exposure pathways of bisphenol A in Korean children and adolescents: Korean National Environmental Health Survey (KoNEHS) 2018-2020.

Bisphenol A (BPA) is an endocrine-disrupting chemical commonly used in manufacturing plastic products. Despite ongoing efforts and regulatory measures, BPA exposure among children persists. This study aimed to identify the modifiable factors associated with urinary BPA levels in Korean children and adolescents. We conducted an environment-wide association study (EWAS) using data from the Korean National Environmental Health Survey (KoNEHS) Cycle 4. This study included 578 preschoolers, 736 school-aged children, and 828 adolescents. A total of 117, 103, and 102 modifiable factors were selected from KoNEHS Cycle 4. Each modifiable factor associated with urinary BPA levels was tested using a multivariable linear regression model. Subsequently, multiple testing corrections were performed using false discovery rate (FDR) estimation. For the validation phase, we used the iteration of the least absolute shrinkage and selection operator (LASSO), a machine learning-based regression analysis. After the validation phase of the LASSO regression, two modifiable factors were identified as being significantly related to urinary BPA levels in preschoolers. Urinary cotinine levels and the use of slime or clay toys were positively associated with urinary BPA levels in preschoolers. However, no significant associations were observed between school-aged children and adolescents. Our results suggest novel exposure pathways to BPA in recent lifestyles and contribute to the development of effective prevention strategies. These modifiable factors provide valuable targets for interventions aimed at reducing BPA exposure in children. Further research is needed to explore additional modifiable factors and confirm our results in larger and more diverse populations.

Relationship between shellfish consumption and urinary phthalate metabolites: Korean National Environmental Health Survey (KoNEHS) cycle 3 (2015-2017).

Background: Phthalates are endocrine disrupting chemicals that are widely used in the production of items of daily life such as in polyvinylchloride plastics, insecticides, and medical devices. This study aimed to determine the association between phthalate exposure and shellfish consumption using data from the Korean National Environmental Health Survey (KoNEHS) cycle 3 (2015-2017), which is a nationally representative survey. Methods: In this study, we analyzed the KoNEHS cycle 3 data of 3,333 (1,526 men and 1,807 women) adults aged more than 19 years. Data related to the variables of sociodemographic factors, health-related behaviors, dietary factors, seafood consumption frequency, and urinary phthalate metabolites concentrations were collected. The concentrations of urinary phthalate metabolites of all the participants were divided into quartiles to define high and low concentration groups based on the 75th percentile concentration. A χ2 test was conducted to analyze the distribution of independent variables. To analyze the relationship between shellfish consumption and phthalate exposure, the odds ratios (ORs) were calculated using logistic regression analysis. Results: Total adults with shellfish consumption frequency of over once a week showed the following adjusted ORs for high concentrations of the following metabolites compared with the group that consumed shellfish once a week or less: 1.43 (95% confidence interval [CI]: 1.01-2.06) for mono-(2-ethyl-5-oxohexyl) phthalate (MEOHP), 1.43 (95% CI: 1.01-2.03) for mono-(2-ethyl-5-carboxypentyl) phthalate (MECPP), 1.57 (95% CI: 1.10-2.24) for ∑di-2-ethylhexyl phthalate (∑DEHP), 2.01 (95% CI: 1.46-2.77) for mono-carboxyoctyl phthalate (MCOP), 1.56 (95% CI: 1.11-2.18) for mono-carboxy-isononly phthalate (MCNP), and 2.57 (95% CI: 1.85-3.56) for mono (3-carboxypropyl) phthalate (MCPP). Conclusions: The concentrations of urinary phthalate metabolites (MEOHP, MECPP, ∑DEHP, MCOP, MCNP, and MCPP) were higher in adults with a higher frequency of shellfish consumption.

Exposure to volatile organic compounds and polycyclic aromatic hydrocarbons is associated with the risk of non-alcoholic fatty liver disease in Korean adolescents: Korea National Environmental Health Survey (KoNEHS) 2015-2017.

Non-alcoholic fatty liver disease (NAFLD) is one of the most frequent liver diseases among adolescents. Several animal studies have suggested that volatile organic compounds (VOCs) and polycyclic aromatic hydrocarbons (PAHs) increase NAFLD risk. However, few epidemiological studies have confirmed the association between VOCs, PAHs and NAFLD in the general adolescent population. Therefore, we analyzed 798 adolescents from the Korean National Environmental Health Survey (KoNEHS), 2015-2017, to examine the associations of urinary metabolites of VOCs and PAHs with serum alanine aminotransferase (ALT) activity and NAFLD prevalence. We performed linear regression, logistic regression, and Bayesian kernel machine regression (BKMR) to evaluate the association of urinary VOCs and PAHs metabolites with ALT levels and NAFLD prevalence. After adjusting for all covariates, urinary benzylmercapturic acid and 2-hydroxyfluorene levels were found to increase ALT activity and NAFLD prevalence. Additionally, the BKMR analyses showed a significantly positive overall effect on ALT activity and NAFLD prevalence with urinary concentrations of VOCs and PAHs metabolites, with 2-hydroxyfluorene as the biggest contributor. Our study suggests that exposure to low-level VOCs and PAHs may have a detrimental effect on NAFLD risk in adolescents. Given the increasing prevalence of NAFLD in adolescents, future cohort studies are confirmed to comprehend the effect of these chemicals on NAFLD risk.

Relationship between the use of plastics in refrigerator food storage and urine phthalate metabolites: the Korean National Environmental Health Survey (KoNEHS) cycle 3.

Background: Plastics are high-molecular-weight materials composed of long carbon chains. They are prevalent in daily life, present in various items such as food containers and microwavable packaging. Phthalates, an additive used to enhance their flexibility, are endocrine-disrupting chemicals. We utilized the data from the Korean National Environmental Health Survey (KoNEHS) cycle 3, representing the general South Korean population, to investigate the relationship between the use of plastics in refrigerator food storage and phthalate exposure. Methods: We assessed 3,333 adult participants (aged ≥ 19 years) including 1,526 men and 1,807 women, using data from KoNEHS cycle 3. Using the 75th percentile concentration, urine phthalate metabolites were categorized into high and low-concentration groups. χ2 test was conducted to analyze variations in the distribution of each variable, considering sociodemographic factors, health-related factors, food intake, the use of plastics, and the concentration of urine phthalate metabolites as the variables. To calculate odds ratios (ORs) for the high-concentration group of urine phthalate metabolites based on the use of plastics in refrigerator food storage, logistic regression analysis was conducted. Results: In men, the use of plastics in refrigerator food storage had significantly higher adjusted ORs compared to those using the others. The adjusted ORs were calculated as follows: mono-(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP) had an OR of 1.35 (95% confidence interval [CI]: 1.05-1.72), mono-(2-ethyl-5-oxohexyl) phthalate (MEOHP) had an OR of 1.48 (95% CI: 1.16-1.88), mono-(2-ethyl-5-carboxypentyl) phthalate (MECPP) had an OR of 1.32 (95% CI: 1.04-1.66), ∑di(2-ethylhexyl) phthalate (∑DEHP) had an OR of 1.37 (95% CI: 1.08-1.74) and mono-n-butyl phthalate (MnBP) had an OR of 1.44 (95% CI: 1.13-1.84). Conclusion: The concentrations of urine phthalate metabolites (MEHHP, MEOHP, MECPP, ∑DEHP, and MnBP) were significantly higher in men who used plastics in refrigerator food storage compared to those using the others.

Association of metabolites of benzene and toluene with lipid profiles in Korean adults: Korean National Environmental Health Survey (2015-2017).

BACKGROUND: Environmental exposure to benzene and toluene is a suspected risk factor for metabolic disorders among the general adult population. However, the effects of benzene and toluene on blood lipid profiles remain unclear. In this study, we investigated the association between urinary blood lipid profiles and metabolites of benzene and toluene in Korean adults. METHODS: We analyzed the data of 3,423 adults from the Korean National Environmental Health Survey Cycle 3 (2015-2017). We used urinary trans,trans-muconic acid (ttMA) as a biomarker of benzene exposure, and urinary benzylmercapturic acid (BMA) as an indicator of toluene exposure. Multivariate logistic regression analyses were performed to explore the association between blood lipid profiles and urinary metabolites of benzene and toluene. Additionally, we examined the linear relationship and urinary metabolites of benzene and toluene between lipoprotein ratios using multivariate regression analyses. RESULTS: After adjusting for covariates, the fourth quartile (Q4) of ttMA [odds ratio (OR) (95% confidence interval, CI = 1.599 (1.231, 2.077)] and Q3 of BMA [OR (95% CI) = 1.579 (1.129, 2.208)] were associated with an increased risk of hypertriglyceridemia. However, the Q4 of urinary ttMA [OR (95% CI) = 0.654 (0.446, 0.961)] and Q3 of urinary BMA [OR (95% CI) = 0.619 (0.430, 0.889)] decreased the risk of a high level of low-density lipoprotein cholesterol (LDL-C). Higher urinary ttMA levels were positively associated with the ratio of triglycerides to high-density lipoproteins [Q4 compared to Q1: ß = 0.11, 95% CI: (0.02, 0.20)]. Higher urinary metabolite levels were negatively associated with the ratio of low-density lipoprotein to high-density lipoprotein [Q4 of ttMA compared to reference: ß = -0.06, 95% CI: (-0.11, -0.01); Q4 of BMA compared to reference: ß = -0.13, 95% CI: (-0.19, -0.08)]. CONCLUSION: Benzene and toluene metabolites were significantly and positively associated with hypertriglyceridemia. However, urinary ttMA and BMA levels were negatively associated with high LDL-C levels. These findings suggest that environmental exposure to benzene and toluene disrupts lipid metabolism in humans.

Urinary 3-phenoxybenzoic acid (3-PBA) levels and changes in hematological parameters in Korean adult population: A Korean National Environmental Health Survey (KoNEHS) 2012-2014 analysis.

Pyrethroid insecticides have been broadly used as pest control in agriculture and residential spaces, exerting high effectiveness of insecticidal property and relatively low toxicity to humans. Several animal studies suggested that exposure to pyrethroids may induce hematological abnormalities, thereby altering the number of blood cells and resulting in blood disorders. However, no epidemiologic study has reported on the effect of pyrethroid insecticide exposure on hematological changes, except for occupational exposure. This study aimed to investigate the effect of urinary 3-phenoxybenzoic acid (3-PBA) concentrations on hematological parameters in a representative South Korean adult population. We analyzed data from 6296 adults enrolled in the Korean National Environmental Health Survey (2012-2014). We employed multiple linear regression analysis to evaluate the association of urinary 3-PBA levels with eight hematological profiles: white blood cells (WBCs), red blood cells (RBCs), hemoglobin, hematocrit, platelets, mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), and mean corpuscular hemoglobin concentration (MCHC). The urinary 3-PBA levels were negatively associated with WBC, RBC, and hemoglobin levels and positively associated with MCV levels. The direction and magnitude of the association between the 3-PBA and hematological parameters varied according to sex and age. The adverse effects of 3-PBA on hematological parameters were distinctive among males aged 60 years and older. In this age group, 3-PBA levels were negatively associated with the WBC, RBC, hemoglobin, hematocrit, and MCHC levels among males. This study is the first to verify that urinary 3-PBA concentrations at the levels found in a Korean population are associated with blood parameters. This finding merits further investigation to understand the impact of 3-PBA on human blood function and public health.

Risk of Nonalcoholic Fatty Liver Disease Is Associated with Urinary Phthalate Metabolites Levels in Adults with Subclinical Hypothyroidism: Korean National Environmental Health Survey (KoNEHS) 2012-2014.

Nonalcoholic fatty liver disease (NAFLD) is a condition of excess accumulation of fats in the liver. Thyroid dysfunction is commonly observed in adult populations with NAFLD. In subjects with thyroid dysfunction, phthalates, which are chemical compounds widely used to increase the flexibility of various plastic products, may increase the risk of NAFLD prevalence. Therefore, our study aimed to evaluate the relationship between the levels of urinary phthalate metabolites and the risk of NAFLD stratified by the levels of thyroid-stimulating hormone (TSH). Data (n = 2308) were obtained from the Korean National Environmental Health Survey II (2012−2014). Using the hepatic steatosis index, participants were classified into non-NAFLD (<30) and NAFLD (>36) groups. Participants with euthyroidism were defined as 0.45−4.5 mIU/L for serum TSH and normal thyroxine (T4) levels (n = 2125). Subclinical hypothyroidism (SCH) was defined as a higher TSH level (4.5−10 mIU/L) with normal total T4 levels in the serum (n = 183). A multivariate analysis was performed to assess the association of the urinary phthalate concentration with the risk of NAFLD after stratification based on the thyroid hormone levels. The levels of phthalate metabolites in urine were not significantly associated with NAFLD in adults with euthyroidism. However, a significant increased risk of NAFLD in those with SCH was observed in the fourth quartile of mono (2-ethyl-5-hydroxyhexyl) phthalate (odds ratio (OR) 13.59, 95% confidence interval (CI) 12.13−86.44), mono (2-ethyl-5-oxohexyl) phthalate (OR 8.55, 95% CI 1.20−60.53), mono-(2-ethyl-5-carboxypentyl) phthalate (OR 9.06, 95% CI 1.78−45.96), and mono-benzyl phthalate (OR 6.05, 95% CI 1.62−22.54) compared to those of the lowest quartile after being adjusted with covariates. In conclusion, the levels of phthalate metabolites in urine are positively associated with NAFLD in adults with SCH. More experimental studies are needed to clarify the risk of NAFLD caused by phthalate exposure in cases with poor thyroid function.

The association between urinary bisphenol A levels and nonalcoholic fatty liver disease in Korean adults: Korean National Environmental Health Survey (KoNEHS) 2015-2017.

BACKGROUND: Nonalcoholic fatty liver disease (NAFLD) is becoming a global health problem. Bisphenol A (BPA), one of most widely used environmental chemicals, is suspected to be a contributor to the development NAFLD. This study was performed to examine the relationship between human BPA levels and risk of NAFLD. METHODS: The data (n = 3476 adults: 1474 men and 2002 women) used in this study were obtained from the Korean National Environmental Health Survey III (2015-2017). BPA levels were measured in urine samples. NAFLD was defined using hepatic steatosis index after exclusion of other causes of hepatic diseases. RESULTS: There was a significant linear relationship between the elevated urinary BPA concentrations and risk of NAFLD. In a univariate analysis, odds ratio (OR) of the highest quartile of urinary BPA level was 1.47 [95% confidence interval (CI) 1.11-1.94] compared to the lowest quartile. After adjusted with covariates, the ORs for NAFLD in the third and fourth quartiles were 1.31 [95% CI 1.03-1.67] and 1.32 [95% CI 1.03-1.70], respectively. CONCLUSIONS: Urinary BPA levels are positively associated with the risk of NAFLD in adults. Further experimental studies are needed to understand the molecular mechanisms of BPA on NAFLD prevalence.

Association between Blood Mercury Levels and Non-Alcoholic Fatty Liver Disease in Non-Obese Populations: The Korean National Environmental Health Survey (KoNEHS) 2012-2014.

Mercury is widely distributed in the environment, and a plausible association between mercury exposure and hepatic damage has been reported. Non-alcoholic fatty liver disease (NAFLD), which comprises a spectrum of liver diseases, has recently been recognized in non-obese subjects. However, there have been no studies on the relationship between internal mercury levels and NAFLD in non-obese individuals. Therefore, we investigated the association between blood mercury levels and NAFLD in non-obese subjects. Cross-sectional data (n = 5919) were obtained from the Korean National Environmental Health Survey (2012-2014). NAFLD was defined using the hepatic steatosis index (HSI). Blood mercury levels were log-transformed and divided into quartiles based on a weighted sample distribution. The association between blood mercury levels and NAFLD was analyzed using a multivariate logistic analysis after body mass index stratification. The geometric mean of blood mercury in the overweight group was significantly higher than that of the non-obese group (p < 0.001). The weighted frequencies of patients with NAFLD based on the HSI were 3.0-7.2% for the non-obese subjects and 52.3-63.2% for the overweight subjects. In the multivariate analysis, blood mercury levels were positively associated with NAFLD for both the overweight and non-obese groups (all p for trend < 0.001). Increased blood mercury levels are closely associated with NAFLD. In particular, mercury could be a risk factor for NAFLD in the non-obese population.

Urinary Phthalate Levels Associated with the Risk of Nonalcoholic Fatty Liver Disease in Adults: The Korean National Environmental Health Survey (KoNEHS) 2012-2014.

The prevalence of nonalcoholic fatty liver disease (NAFLD) is increasing worldwide. Recent experimental studies suggested that phthalates might induce NAFLD. Therefore, this study aimed to investigate the relationship between phthalates metabolites and NAFLD in the human population. This cross-sectional analysis was performed using data from the Korean National Environmental Health Survey II (2012-2014) among Korean adults (n = 5800). NAFLD was diagnosed using the hepatic steatosis index (HSI) in the absence of other causes of chronic liver diseases. Among the participants (mean age 46 years, 47.5% male), the prevalence of NAFLD was associated with urinary levels of mono(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP), mono-(2-ethyl-5-oxohexyl) phthalate, mono-(2-ethyl-5-carboxypentyl) phthalate, mono-benzyl phthalate (MBzP), and mono-n-butyl phthalate (MnBP) compared to the reference group. In the multivariate model, the odds ratios (ORs), 95% confidence interval (CI) for NAFLD were 1.33 (1.00-1.78) and 1.39 (1.00-1.92) in the 3rd and 4th quartile of MEHHP, respectively. Based on the study findings, high levels of urinary phthalates are associated with the prevalence of NAFLD in Korean adults. Further investigation is required to elucidate the causal relationship.

The association between urinary bisphenol A levels and nonalcoholic fatty liver disease in Korean adults: Korean National Environmental Health Survey (KoNEHS) 2015-2017

BACKGROUND@#Nonalcoholic fatty liver disease (NAFLD) is becoming a global health problem. Bisphenol A (BPA), one of most widely used environmental chemicals, is suspected to be a contributor to the development NAFLD. This study was performed to examine the relationship between human BPA levels and risk of NAFLD.@*METHODS@#The data (n = 3476 adults: 1474 men and 2002 women) used in this study were obtained from the Korean National Environmental Health Survey III (2015-2017). BPA levels were measured in urine samples. NAFLD was defined using hepatic steatosis index after exclusion of other causes of hepatic diseases.@*RESULTS@#There was a significant linear relationship between the elevated urinary BPA concentrations and risk of NAFLD. In a univariate analysis, odds ratio (OR) of the highest quartile of urinary BPA level was 1.47 [95% confidence interval (CI) 1.11-1.94] compared to the lowest quartile. After adjusted with covariates, the ORs for NAFLD in the third and fourth quartiles were 1.31 [95% CI 1.03-1.67] and 1.32 [95% CI 1.03-1.70], respectively.@*CONCLUSIONS@#Urinary BPA levels are positively associated with the risk of NAFLD in adults. Further experimental studies are needed to understand the molecular mechanisms of BPA on NAFLD prevalence.

Relationship between seafood consumption and bisphenol A exposure: the Second Korean National Environmental Health Survey (KoNEHS 2012-2014).

BACKGROUND: This study aimed to identify the relationship between exposure to bisphenol A (BPA) and seafood consumption using a nationally representative data of the general Korean population. METHODS: This study was conducted on 5,402 adults aged 19 years and older (2,488 men, 2,914 women) based on the second Korean National Environmental Health Survey (2012-2014). We stratified the data according to gender and analyzed urinary BPA concentrations in terms of sociodemographic characteristics, health behavior, dietary factor, and seafood consumption. In the high and low BPA exposure groups, the odds ratios (ORs) were calculated using logistic regression analysis according to the top 75th percentile concentration. RESULTS: In men, large fish and tuna and other seafood categories had significantly higher ORs before and after adjustment in the group who consumed seafood more than once a week than in the group who rarely consumed seafood, with an adjusted value of 1.97 (95% confidence interval [CI]: 1.12-3.48) and 1.74 (95% CI: 1.10-2.75), respectively. In the shellfish category, the unadjusted OR was 1.61 (95% CI: 1.00-2.59), which was significantly higher in the group who consumed seafood more than once a week than in the group who rarely consumed seafood. However, the OR after adjusting for the variables was not statistically significant. In women, the frequency of seafood consumption and the concentration of urinary BPA were not significantly associated. CONCLUSIONS: BPA concentration was higher in men who frequently consumed large fish and tuna, shellfish and other seafood in this study.

Relationship between seafood consumption and bisphenol A exposure: the Second Korean National Environmental Health Survey (KoNEHS 2012–2014)

BACKGROUND: This study aimed to identify the relationship between exposure to bisphenol A (BPA) and seafood consumption using a nationally representative data of the general Korean population.METHODS: This study was conducted on 5,402 adults aged 19 years and older (2,488 men, 2,914 women) based on the second Korean National Environmental Health Survey (2012–2014). We stratified the data according to gender and analyzed urinary BPA concentrations in terms of sociodemographic characteristics, health behavior, dietary factor, and seafood consumption. In the high and low BPA exposure groups, the odds ratios (ORs) were calculated using logistic regression analysis according to the top 75th percentile concentration.RESULTS: In men, large fish and tuna and other seafood categories had significantly higher ORs before and after adjustment in the group who consumed seafood more than once a week than in the group who rarely consumed seafood, with an adjusted value of 1.97 (95% confidence interval [CI]: 1.12–3.48) and 1.74 (95% CI: 1.10–2.75), respectively. In the shellfish category, the unadjusted OR was 1.61 (95% CI: 1.00–2.59), which was significantly higher in the group who consumed seafood more than once a week than in the group who rarely consumed seafood. However, the OR after adjusting for the variables was not statistically significant. In women, the frequency of seafood consumption and the concentration of urinary BPA were not significantly associated.CONCLUSIONS: BPA concentration was higher in men who frequently consumed large fish and tuna, shellfish and other seafood in this study.

The exposure level of environmental harmful substances related to the secondhand smoke in Korean non-smoker adults: data from the second Korean National Environmental Health Survey (KoNEHS 2012-2014): a cross-sectional study.

BACKGROUND: We aimed to find the exposure level of environmental harmful substances related to the secondhand smoke (SHS) using a nationally representative data of the general population in Korea. METHODS: Total 3,533 people were included in this study. We compared the proportion exceeding 95 percentile of the concentrations of harmful substances by sex according to SHS exposure. 16 kinds of substances related to tobacco smoke were analyzed including heavy metals, polycyclic aromatic hydrocarbons, volatile organic compounds, and environmental phenol. For 16 kinds of substances, the odds ratios (ORs) for exceeding 95 percentile of each harmful substance were calculated by multiple logistic regression according to SHS exposure. Age, education level, marital status, body mass index, drinking, and exercise were adjusted as covariates. Cotinine level was additionally adjusted to increase reliability of our results. RESULTS: SHS was associated with high exposure of mercury, methylhippuric acid, fluorene, and cotinine. In women, SHS was associated with mercury, methylhippuric acid, fluorene, and cotinine, while in men, it was associated with cotinine. After adjusting covariates, ORs of blood mercury, methylhippuric acid and hydroxyfluorene in the exposed gruop were greater than that in the non-exposed group. Especially in female, methylhippuric acid and hydroxyfluorene showed consistent result. CONCLUSIONS: Our finding demonstrates that SHS is related to several harmful substances. Therefore, to reduce the health effects of SHS, it is necessary to educate and publicize the risk of SHS. Future studies are necessary to more accurately analyze factors such as exposure frequency, time, and pathway of SHS.

Urinary 3-phenoxybenzoic acid levels and the association with thyroid hormones in adults: Korean National Environmental Health Survey 2012-2014.

BACKGROUND: Owing to insecticidal activity at low doses with relatively low toxicity in humans, synthetic pyrethroids have been used widely for pest control in agricultural and domestic settings. Pyrethroids are suspected for potential endocrine disruption. However, the thyroid disrupting effects of pyrethroids, particularly in humans, is relatively underexplored. OBJECTIVES: This study aimed to report 3-phenoxybenzoic acid (3-PBA) concentrations in urine, and assess its association with serum thyroid hormone (TH) levels in a representative adult population of Korea. METHODS: Data obtained from representative Korean adults recruited in the Korean National Environmental Health Survey (2nd round, 2012-2014) were analyzed. Urinary 3-PBA levels were associated with serum thyroxine (T4), total triiodothyronine (T3), and thyroid-stimulating hormone (TSH) levels among the Korean adult population. RESULTS: Urinary 3-PBA levels among Korean adults were >3 times higher than those reported in Canada and the United States. Urinary 3-PBA levels showed negative association with serum T4, and this pattern was not changed after stratification by sex. For T3, the association varied by sex and exposure levels. Male demonstrated the same inverse association between urinary 3-PBA and T3, but female did not show such association. Among adults in the lower half of urinary 3-PBA levels, the association with T3 was significant, while that among the remainder was marginal. The association with T4 remained significant on sensitivity analysis, after controlling for other urinary chemicals. CONCLUSION: Urinary 3-PBA levels in the general Korean adult population were found to be generally higher than those of other countries, and were associated with decreased TH levels. Considering the importance of THs, the public health implications of pyrethroid insecticide exposure warrant further studies.

Relationship between personal care products usage and triclosan exposure: the second Korean National Environmental Health Survey (KoNEHS 2012-2014).

BACKGROUND: We aimed to find the exposure level of triclosan (TCS), a known endocrine disruptor, related to the use of personal care products using a nationally representative data of the general population in Korea. METHODS: This study included data of 6288 adults aged 19 years and older (2692 men, 3596 women), based on the Second Korean National Environmental Health Survey (KoNEHS 2012-2014). The data were divided according to gender. The frequency and proportion of each variable were determined by dividing participants into two groups based on the top 75th percentile concentration of urinary TCS (male: 1.096 µg/g creatinine, female: 1.329 µg/g creatinine). Odds ratios (ORs) were calculated using logistic regression analysis for the high TCS exposure and low TCS exposure groups. RESULTS: Overall, the proportion of participants using personal care products was higher in women than in men. There was a significantly higher proportion of participants in the high TCS exposure group with younger age, higher education and income levels and with more frequent use of fragrance products, hair care products, body cleansers, cosmetics, and antimicrobial agents. In both men and women, ORs tended to increase with increased frequency of use of hair care products, body cleansers, and cosmetics before and after adjustment. CONCLUSIONS: Our findings demonstrate that as the frequency of use of personal care products increases, urine TCS concentration increases. Because TCS is a well-known endocrine disruptor, further studies are needed and explore other health effects with exposure to TCS in general population in Korea.