Urinary 2-naphthol Concentrations Research Articles

ODP277 Urinary Concentrations of Polycyclic Aromatic Hydrocarbons and Childhood Obesity

Abstract Background Polycyclic aromatic hydrocarbons (PAHs), primarily produced by incomplete combustion of organic materials, have been suggested as obesogens, but information on PAHs and obesity, especially in children, is limited. We examined the cross-sectional association between urinary concentrations of PAHs and obesity in the Korean pediatric population. Methods We analyzed the data of 2286 children and adolescents aged 3–17 years who participated in the Korean National Environmental Health Survey (KoNEHS) 2015–2017. Urinary concentrations of 2-naphthol, 2-hydroxyfluorene, 1-hydroxyphenanthrene, and 1-hydroxypyrene were assayed using gas chromatography-mass spectrometry. Covariate-adjusted standardization method was used for the urinary dilution adjustment. Overweight and obesity were defined as BMI-for-age ≥85th percentile and ≥95th percentile, respectively. Multiple linear and logistic regression models were performed to analyze the relationship of BMI z-score and overweight with urinary concentrations of PAHs after adjusting for age, sex, household income, parental education level, physical activity, fast-food consumption, and ETS exposure. Results Obese children showed significantly higher urinary 2-naphthol concentrations than normal-weighted children in the overall population [3.62 µg/L (95% confidence intervals (95% CI): 3.20, 4. 09) vs. 2.88 µg/L (95% CI: 2.62, 3.16)]. Similar findings were observed in the age groups 6-11 and 12-17 years. Significant increases in BMI z-scores for 10 times increase in urinary 2-naphthol concentrations were observed in the age groups 6-11 [0.31 z-score units, (95% CI: 0.13, 0.49), P = 0. 001] and 12-17 years [0.33 z-score units, (95% CI: 0. 05, 0.60), P=0. 02]. A significant but smaller association was observed between change in BMI z-score and 1-hydroxypyrene concentrations in the 6-11 year group [0.14 z-score units, (95% CI: 0. 02, 0.27), P=0. 03]. The multiple logistic regression models for overweight showed significant positive associations with the quartiles of 2-NAP in the overall population [OR (95% CI); 1.14 (0.83-1.55), 1.39 (1. 03, 1.88), 1.46 (1. 08, 1.99) in the 2nd, 3rd, and 4th quartile, respectively, compared with the 1st quartile; P-for-trend=0. 006]. Similar associations between 2-naphthol and overweight status were also observed in the 6-11 year and 12-17 year groups. Conclusion This result suggests a possible link between PAH exposure, particularly 2-naphthol, and obesity in the Korean pediatric population. Given the growing obesity rates among Asian children and adolescents, this finding warrants further studies on the impacts of long-term exposure of PAHs on childhood obesity and possible mechanisms for this association. Presentation: No date and time listed

Dietary β-Carotine to Reduce Lipid Peroxidation Induced by PAH Exposure of Pregnant Women

ISEE-885 Objective: Prenatal exposure to oxidative stress may explain the adverse pregnancy outcomes and fetal origin of adult disease. The purpose of this study was to investigate the association between the exposure to polycyclic aromatic hydrocarbons (PAHs) and oxidative stress for pregnant women and the modification effect by nutritional factors. Material and Methods: A total of 519 pregnant women who had lived in Seoul, Cheonan and Ulsan, Korea were enrolled from July 2006 through January 2007. We measured urinary 2-naphthol concentrations to represent exposure to PAH and analyzed biomarkers such as urinary Malondialdehyde (MDA) and serum total reactive oxygen species (total ROS) for measurement of oxidative stress. Dietary intake was calculated using 24 hours recall. Other individual characteristics such as exercise, smoking, and alcohol consumption were obtained by a questionnaire completed at the beginning of the study. Results: Mean urinary concentrations of 2-naphthol, MDA, and serum total ROS were 13.41 ± 15.52 mmol/mol creatinine, 2.39 ± 1.86 μmol/g creatinine, and 197.77 ± 64.53 mmol respectively. Urinary concentrations of 2-naphthol were significantly associated with urinary MDA levels (P = 0.002), but not with total ROS concentrations (P = 0.097). Urinary 2-naphthol concentrations remained to be significantly associated with urinary MDA levels after adjusting for age, height, weight, urinary cotinine level, and alcohol consumption. We searched for nutritional factors affecting the relationship and found β-carotine uptake significantly decreases urinary MDA levels associated with urinary 2-naphthol concentrations. Conclusions: Polycyclic aromatic hydrocarbons (PAHs) are important carcinogens which are found in cigarette smoking, coke oven emissions, and diesel exhaust. These results suggest that exposure to PAH affects lipid peroxidation for pregnant women and dietary β-carotine uptake decreases the lipid peroxidation caused by PAH exposure.

환경성 PAHs 노출과 생체지표 연구

The aim of the study was to see if there is any differences in urinary 1-hydroxypyrene glucuronide (1-OHPG) and 2-naphthol levels in children (<TEX>$8{\sim}14$</TEX> years old) and their mothers (<TEX>$30{\sim}46$</TEX> years old) living three cities in South Korea (Seoul, Incheon and Pohang) and three in China (Changchun, Datong and Kunming), where the levels of air pollution varies. The factors related with urinary biomarkers levels were also evaluated. The study subjects consisted of 118 Korean (60 children and 58 their mothers) and 120 Chinese (60 children and 60 their mothers). Urinary 1-OHPG was measured by synchronous fluorescence spectroscopy after immuno-affinity purification using monoclonal antibody 8E11 and urinary 2-naphthol concentrations were determined by HPLC with fluorescence detector. Information on recent consumption of diet containing high PAHs, environmental tobacco smoke (ETS), type of cooking and heating fuels, and other life-style characteristics were collected by self-administered questionnaire. The arithmetic mean of urinary 1-OHPG levels (n = 120, <TEX>$mean{\pm}SD$</TEX>, <TEX>$6.77{\pm}7.96{\mu}mol/mol$</TEX> creatinine) in Chinese were 10 fold higher than those in Korean (n = 118, <TEX>$0.62{\pm}0.61{\mu}mol/mol$</TEX> creatinine) (P < 0.01). Urinary 2-naphthol levels in Chinese (n = 119, <TEX>$59.50{\pm}82.29{\mu}g/g$</TEX> creatinine) were significantly higher than those in Korean (n = 117, <TEX>$25.09{\pm}46.56{\mu}g/g$</TEX> creatinine) (P < 0.01). Urinary 1-OHPG and 2-naphthol levels were significantly higher in children living the polluted cities in China (Datong and Chanchun, respectively). Multiple linear regression analysis indicated that living in factory area (vs. residential area) and use of coal stove as heating fuel were significant predictors for urinary 1-OHPG (overall model <TEX>$R^2$</TEX>= 0.46, n = 204). And ETS was predictor for urinary 2-naphthol levels in Korean (<TEX>$R^2$</TEX> = 0.36, n = 46). These results indicated that urinary 1-OHPG and 2-naphthol levels were related with different ambient particulate air pollution, type of heating fuels and ETS.

Effects of genetic polymorphisms of CYP1A1, CYP2E1, GSTM1, and GSTT1 on the urinary levels of 1-hydroxypyrene and 2-naphthol in aircraft maintenance workers

This study was undertaken to investigate the effects of genetic polymorphisms of the cytochrome P450 1A1 (CYP1A1) and 2E1 (CYP2E1), and glutathione S-transferases mu (GSTM1) and theta (GSTT1) on urinary 1-hydroxypyrene and 2-naphthol levels, and to estimate the level of exposure to polycyclic aromatic hydrocarbons (PAHs) in aircraft maintenance workers. In 218 Korean aircraft maintenance workers, the geometric means of urinary 1-hydroxypyrene and 2-naphthol were 0.32 and 3.25 μmol/mol creatinine, respectively. These urinary concentrations were approximately at the upper limit of the general population. Mean urinary 2-naphthol concentrations were significantly different between smokers and non-smokers. CYP1A1 and GSTM1 were statistically significant in analyses on both 1-hydroxypyrene and 2-naphthol levels among smokers. The results suggest that smoking has more profound effects on urinary PAH metabolites than does genetic polymorphisms in this population, and that CYP1A1 and GSTM1 activity might be related to the metabolism of 1-hydroxypyrene and 2-naphthol.

Effects of occupation, lifestyle and genetic polymorphisms of CYP1A1, CYP2E1, GSTM1 and GSTT1 on urinary 1-hydroxypyrene and 2-naphthol concentrations.

This study was undertaken to determine the effects of occupation, lifestyle and the genetic polymorphisms of cytochrome P450 1A1 (CYP1A1), cytochrome P450 2E1 (CYP2E1) and glutathione S-transferases micro1 (GSTM1) and 1 (GSTT1) on the concentrations of urinary 1-hydroxypyrene (1-OHP) and 2-naphthol among Korean coke oven workers and university students. The study subjects included 90 coke oven workers and 128 university students. A questionnaire was used to obtain detailed data about the work area, smoking habits and food intake of subjects. Associations between urinary polycyclic aromatic hydrocarbon (PAH) concentrations and occupation, smoking status, total airborne PAH level and genetic polymorphisms were tested. Urinary 1-OHP and 2-naphthol concentrations were higher in coke oven workers than in students and correlated significantly with work area. Urinary 2-naphthol concentrations increased with an increase in the level of cigarette smoking in students. Total airborne PAH level correlated with urinary 1-OHP concentration in coke oven workers. Urinary 1-OHP and 2-naphthol concentrations were higher in coke oven workers with the c1/c2 or c2/c2 genotype of CYP2E1 than in those with the c1/c1 genotype. Urinary 2-naphthol concentrations were higher in GSTM1-null workers than in GSTM1-positive workers. In multiple regression analysis CYP2E1 was a significant factor determining urinary 1-OHP concentrations in coke oven workers. CYP2E1 and GSTM1 were significant determinants for urinary 2-naphthol concentrations in coke oven workers and GSTM1 and smoking were prognosticators among university students. Urinary 1-OHP is a better indicator of occupational exposure to PAH in coke oven workers than 2-naphthol, whereas urinary 2-naphthol may be more sensitive for non-occupational inhalation exposure to PAH. In occupationally exposed populations CYP2E1 and GSTM1 appear to play an important role in the metabolism of pyrene and naphthalene. In individuals not occupationally exposed to PAHs GSTM1 and smoking seem to influence the urinary concentration of 2-naphthol.

Urinary 1-hydroxypyrene and 2-naphthol concentrations in male Koreans.

Urinary 1-hydroxypyrene (1-OHP) has been used as a biological marker of exposure to polycyclic aromatic hydrocarbons (PAHs), and urinary 2-naphthol is suggested as a new marker for route-specific exposure to airborne PAHs. We analyzed urinary 1-OHP and 2-naphthol concentrations in 292 male Koreans (129 university students and 163 shipyard workers) to define the distribution pattern in Koreans with no or low occupational exposure to PAHs. Histories of cigarette smoking and the eating of PAH-containing foods were obtained by a self-administered structured questionnaire. Urine samples were collected and urinary 1-OHP and 2-naphthol concentrations were measured using high-performance liquid chromatography (HPLC). The arithmetic (geometric) means of urinary 1-OHP and 2-naphthol concentrations for all students, expressed as micromoles per mole of creatinine, were 0.04 (0.04) and 3.12 (2.22), for non-smokers 0.03 (0.03) and 1.78 (1.30) and for smokers 0.05 (0.03) and 4.36 (3.62), respectively. Among shipyard workers, the arithmetic (geometric) means of urinary 1-OHP and 2-naphthol concentrations were 0.69 (0.31) and 4.37 (2.62) for all, 0.27 (0.18) and 2.46 (1.16) for nonsmokers, and 0.97 (0.44) and 5.60 (4.44) for smokers, respectively. Mean urinary 1-OHP and 2-naphthol concentrations differed significantly between nonsmokers and smokers both in students and in shipyard workers. In smokers, some variables related to smoking habit were positively correlated with urinary 1-OHP and with 2-naphthol concentrations. The latter showed better correlations with the variables related to smoking amount than the former. None of the food-related factors was significantly correlated with urinary 1-OHP or 2-naphthol concentration. These results suggest that urinary 2-naphthol concentration is more sensitively affected by smoking status than urinary 1-OHP concentration and that urinary 2-naphthol is a sensitive marker for low-level inhalation of PAHs.