Contributions of dietary, demographic, disease, lifestyle and other factors in explaining variabilities in concentrations of selected monohydroxylated polycyclic aromatic hydrocarbons in urine: Data for US children, adolescents, and adults

Environmental and dietary factors associated with urinary OH-PAHs in mid-pregnancy in a large multi-site study

BACKGROUND

PAH exposure is associated with adverse health outcomes, but exposure sources in pregnancy are not well-understood.

OBJECTIVES

We examined associations between urinary OH-PAHs during pregnancy and environmental tobacco smoke (ETS) and short-term ambient air pollution exposure. Participants included 1603 pregnant non-smokers in three cohorts from 7 sites across the USA. We also examined associations with intake of foods typically high in PAHs in one cohort with dietary assessment data (n = 801).

METHODS

Urinary OH-PAHs were measured using LC-MS/MS; urinary cotinine was measured using SPE/UPLC-MS/MS. To accommodate different detection limits by cohort, ETS exposure was represented by modified cotinine quartiles; these combined concentrations below the highest detection limit in the first category (0-0.017 ng/mL), with the rest divided evenly into three categories (0.0171-0.2 ng/mL, 0.21-1.191 ng/mL, 1.192-1465 ng/mL). Air pollution exposure was represented by quartiles of same-day ambient PM2.5 in residential census tracts estimated from EPA's Downscaler Model. We fitted separate Tobit regression models for log-OH-PAH concentrations in association with cotinine or ambient PM2.5 quartile adjusted for specific gravity, site, batch, household income, education, employment status, neighborhood deprivation index, season, and year. For the food model, PAH dietary intakes were estimated using food frequency questionnaire data and standard portion weights from a national database.

RESULTS

In adjusted models, the highest modified cotinine quartile vs. the lowest was associated with 48% (95% CI: 13%, 94%) higher urinary 1-hydroxynaphthalene, 36% (15%, 61%) higher 2-hydroxynaphthalene, 41% (23%, 63%) higher 3-hydroxyphenanthrene, and 70% (28%, 127%) higher 1-hydroxypyrene. Second and third quartile cotinine concentrations were associated with higher OH-PAHs, although not consistently. Same-day ambient PM2.5 was not associated with any OH-PAH, nor was self-reported dietary intake.

CONCLUSIONS

ETS is a major source of PAH exposure for pregnant people in the USA while ambient PM2.5 and diet measured via usual intakes appear less influential. Our findings underscore the importance of policies/actions to reduce environmental tobacco smoke exposure among pregnant people.

Urinary polycyclic aromatic hydrocarbon metabolites and their association with oxidative stress among pregnant women in Los Angeles

BACKGROUND

Polycyclic aromatic hydrocarbons (PAHs) have been linked to adverse birth outcomes that have been reported to be induced by oxidative stress, but few epidemiological studies to date have evaluated associations between urinary PAH metabolites and oxidative stress biomarkers in pregnancy and identified critical periods for these outcomes and PAH exposures in pregnancy.

METHODS

A cohort of pregnant women was recruited early in pregnancy from antenatal clinics at the University of California Los Angeles during 2016-2019. We collected urine samples up to three times during pregnancy in a total of 159 women enrolled in the cohort. A total of 7 PAH metabolites and 2 oxidative stress biomarkers [malondialdehyde (MDA), 8-hydroxy-2'-deoxyguanosine (8-OHdG)] were measured in all available urine samples. Using multiple linear regression models, we estimated the percentage change (%) and 95% confidence interval (CI) in 8-OHdG and MDA measured at each sample collection time per doubling of PAH metabolite concentrations. Furthermore, we used linear mixed models with a random intercept for participant to estimate the associations between PAH metabolite and oxidative stress biomarker concentrations across multiple time points in pregnancy.

RESULTS

Most PAH metabolites were positively associated with both urinary oxidative stress biomarkers, MDA and 8-OHdG, with stronger associations in early and late pregnancy. A doubling of each urinary PAH metabolite concentration increased MDA concentrations by 5.8-41.1% and 8-OHdG concentrations by 13.8-49.7%. Linear mixed model results were consistent with those from linear regression models for each gestational sampling period.

CONCLUSION

Urinary PAH metabolites are associated with increases in oxidative stress biomarkers during pregnancy, especially in early and late pregnancy.

Possible relationship between respiratory diseases and urinary concentrations of polycyclic aromatic hydrocarbon metabolites - a pilot study

This study investigates the potential relationship between exposure to polycyclic aromatic hydrocarbons (PAHs), specifically monohydroxylated metabolites (OH-PAHs), in urine, and the prevalence of respiratory diseases in 2-year-old children residing in two locations within the Czech Republic - České Budějovice (control location) and the historically contaminated mining district of Most. Despite current air quality and lifestyle similarities between the two cities, our research aims to uncover potential long-term health effects, building upon previous data indicating distinctive patterns in the Most population. A total of 248 urine samples were analysed for the presence of 11 OH-PAHs. Employing liquid-liquid extraction with ethyl acetate and clean-up through dispersive solid-phase extraction, instrumental analysis was conducted using ultra-high performance liquid chromatography coupled with tandem mass spectrometry. The incidence of respiratory diseases was assessed through questionnaires administered by paediatricians. The concentrations of OH-PAHs were elevated in urine samples from 2-year-olds in Most compared to those from České Budějovice. The incidence of respiratory diseases showed statistically significant higher levels of OH-PAHs in children from Most, together with a higher incidence of influenza. This association underlines the impact of environmental PAH exposure on children's respiratory health. It suggests that elevated urinary OH-PAH levels indicate an increased risk of developing respiratory diseases in the affected population. Further studies are needed to clarify the possible long-term health effects and to contribute to sound public health strategies.

Baseline data and associations between urinary biomarkers of polycyclic aromatic hydrocarbons, blood pressure, hemogram, and lifestyle among wildland firefighters

Introduction

Available literature has found an association between firefighting and pathologic pathways leading to cardiorespiratory diseases, which have been linked with exposure to polycyclic aromatic hydrocarbons (PAHs). PAHs are highlighted as priority pollutants by the European Human Biomonitoring Initiative in occupational and non-occupational contexts.

Methods

This cross-sectional study is the first to simultaneously characterize six creatinine-adjusted PAHs metabolites (OHPAHs) in urine, blood pressure, cardiac frequency, and hemogram parameters among wildland firefighters without occupational exposure to fire emissions (> 7 days), while exploring several variables retrieved via questionnaires.

Results

Overall, baseline levels for total OHPAHs levels were 2 to 23-times superior to the general population, whereas individual metabolites remained below the general population median range (except for 1-hydroxynaphthalene+1-hydroxyacenaphtene). Exposure to gaseous pollutants and/or particulate matter during work-shift was associated with a 3.5-fold increase in total OHPAHs levels. Firefighters who smoke presented 3-times higher total concentration of OHPAHs than non-smokers (p < 0.001); non-smoker females presented 2-fold lower total OHPAHs (p = 0.049) than males. 1-hydroxypyrene was below the recommended occupational biological exposure value (2.5 μg/L), and the metabolite of carcinogenic PAH (benzo(a)pyrene) was not detected. Blood pressure was above 120/80 mmHg in 71% of subjects. Firefighters from the permanent intervention team presented significantly increased systolic pressure than those who performed other functions (p = 0.034). Tobacco consumption was significantly associated with higher basophils (p = 0.01-0.02) and hematocrit (p = 0.03). No association between OHPAHs and blood pressure was found. OHPAHs concentrations were positively correlated with monocyte, basophils, large immune cells, atypical lymphocytes, and mean corpuscular volume, which were stronger among smokers. Nevertheless, inverse associations were observed between fluorene and pyrene metabolites with neutrophils and eosinophils, respectively, in non-smokers. Hemogram was negatively affected by overworking and lower physical activity.

Conclusion

This study suggests possible associations between urinary PAHs metabolites and health parameters in firefighters, that should be further assessed in larger groups.

Risk assessment and predictors of the exposure to polycyclic aromatic hydrocarbons in Spanish adults by urinary human biomonitoring

Polycyclic aromatic hydrocarbons (PAHs) are produced primarily during incomplete combustion of organic matter and in various industrial processes. They are widespread environmental pollutants that are of significant interest due to their potential toxicity. Humans can be exposed to PAHs through ingestion, inhalation and dermal contact. In the present study, ten urinary PAH biomarkers were determined in first-morning urine samples (n = 504) from the adult population (aged 18-65 years) residing in the Valencian Region of Spain. These samples were analysed using liquid-liquid extraction followed by high-performance liquid chromatography coupled to tandem mass spectrometry (HPLC-MS/MS). All PAH biomarkers were quantified in more than 65 % of the urine samples. Naphthalene biomarkers, 1-hydroxynaphthalene (1OHNAP) and 2-hydroxynaphthalene (2OHNAP), exhibited the highest levels with geometric means (GMs) of 0.7 and 11.9 μg L-1, respectively. The 95th percentile of all PAH biomarkers ranged from 0.22 to 64.8 μg L-1. Estimated daily intakes (EDIs) for the analysed PAH families in the studied population ranged from 17 (pyrene) to 18581 (naphthalene) ng·kg-bw-1·day-1 (GM). Significant associations were observed between the quantified urinary metabolites of PAHs and smoking status, home location, annual household incomes, BMI, and the consumption of grilled food in the last 24 h. Hazard quotients (HQs) of naphthalene and consequently, hazard indexes (HIs) were above 1, especially for smokers. Therefore, potential health risks associated with PAH exposure in the target population could not be discarded.

Coking-Produced Aromatic Compounds in Urine of Exposed and Nonexposed Populations: Exposure Levels, Source Identification, and Model-Based Health Implications

Coking contamination in China is complex and poses potential health risks to humans. In this study, we collected urine samples from coking plant workers, nearby residents, and control individuals to analyze 25 coking-produced aromatic compounds (ACs), including metabolites of polycyclic aromatic hydrocarbons (PAHs) and their derivatives, chlorophenols, and nitrophenols. The median concentration of total ACs in urine of workers was 102 μg·g-1 creatinine, significantly higher than that in the other two groups. Hydroxy-PAHs and hydroxy hetero-PAHs were the dominant ACs. Workers directly exposed from coking industrial processes, i.e., coking, coal preparation, and chemical production processes, showed higher concentrations of hydroxy-PAHs and hydroxy hetero-PAHs (excluding 5-hydroxyisoquinoline), while those from indirect exposure workshops had higher levels of other ACs, indicating different sources in the coking plant. The AC mixture in workers demonstrated positive effects on DNA damage and lipid peroxidation with 5-hydroxyisoquinoline and 3-hydroxycarbazole playing a significant role using a quantile g-computation model. Monte Carlo simulation revealed that coking contamination elevated the carcinogenic risk for exposed workers by 5-fold compared to controls with pyrene, pentachlorophenol, and carbazole contributing the most, and workers from coking process are at the highest risk. This study enhances understanding of coking-produced AC levels and provides valuable insights into coking contamination control.

Human biomonitoring and reference values of urinary 1-hydroxypyrene among Iranian adults population

Polycyclic aromatic hydrocarbons (PAHs) are one of the most important environmental pollutants. Urinary concentrations of 1-hydropyren metabolites of PAHs have been used as biomarkers of these chemicals' exposure in humans. This cross-sectional study was conducted on 468 healthy Iranian adults over 25 years old and non-smokers in six provinces who were selected based on the clustering method. Fasting urine sampling and body composition and demographic measurements were performed. Urine samples were analyzed by GC-MS. The analysis included descriptive statistics and analytical statistics using multiple linear regression by Python software. 1-Hydroxypyrene was found in 100% of samples, and the mean (Reference Value 95%) concentration of 1-hydroxypyrene was 6.12 (RV 95%: 20) μg/L and 5.95 (21) μg/gcrt. There was a direct relationship between the amount of body composition (body fat, visceral fat), BMI, and age with the urinary concentrations of 1-hydropyren metabolites, and this relationship was significant for BMI with urinary concentrations of 1-hydropyren metabolites (P = 0.045). The amount of 1-hydroxypyrene in healthy Iranian adults has been higher than in similar studies in other countries. These results provide helpful information regarding the exposure of Iranian adults to 1-hydroxypyrene, and these data can be used to supplement the national reference values of human biomonitoring for the interpretation of biomonitoring results.

Internal exposure risk based on urinary metabolites of PAHs of occupation and non-occupation populations around a non-ferrous metal smelting plant

The emission of various metals from non-ferrous metal smelting activities is well known. However, relative investigations on potential occupational exposure of organic pollutants are still limited. Herein, total of 619 human urine samples were collected from workers engaged in smelting activities and residents living near and/or far from the smelting sites, and ten mono-hydroxylated metabolites of polycyclic aromatic hydrocarbons (OH-PAHs) in human urine were determined. The median levels of Σ₁₀OH-PAHs in smelting workers (25.6 ng/mL) were significantly higher (p < 0.01) than that of surrounding residents (9.00 ng/mL) and rural residents as the control (8.17 ng/mL), indicating an increase in occupational PAH exposure in non-ferrous metal smelting activities. The composition profiles of OH-PAH congeners were similar in three groups, in which naphthalene metabolites accounted for 76-82% of the total. The effects of smoking, drinking, gender, BMI, and occupational categories on urinary OH-PAHs were considered. The partial correlation analysis showed an insignificant effect of non-ferrous metal smelting activities on PAH exposure for surrounding residents. In the health risk assessments, almost all smelting workers had cancer risks exceeded the acceptable level of 10^-6. This study provides a reference to occupational PAH exposure and reinforce the necessary of health monitoring among smelting workers.

Associations between concentrations of serum α-klotho and selected urinary monohydroxy metabolites of polycyclic aromatic hydrocarbons: data for US adults aged 40-79 years

For the first time, the associations between urinary concentrations of oxidant polycyclic aromatic hydrocarbon (PAH) metabolites and serum concentrations of anti-oxidant α-klotho were estimated for US adults aged 40-79 years. Multivariate regression models with α-klotho as dependent variable and one of the urinary metabolite of PAH as independent variables were fitted. In the absence of albuminuria and normal (eGFR > 90 mL/min/1.73 m²) kidney function, 10% increases in concentrations of 2-hydroxynaphthalene, 9-hydroxyfluorene, and ∑PAH were associated with 0.25%, 0.32%, and 0.19% decreases in serum α-klotho concentrations. In the absence of albuminuria and near normal (60 <  = eGFR < 90 mL/min/1.73 m²) kidney function, 10% increases in concentrations of 1-hydroxynaphthalene, 9-hydroxyfluorene, 1-hydroxyphenanthrene, and ∑PAH were associated with 0.17%, 0.38%, 0.34%, and 0.18% decreases in serum α-klotho concentrations. To what degree, these mild decreases in α-klotho are a matter of concern, is a subject ripe for discussion and additional investigations. When kidney function was normal or near normal but albuminuria was present, the associations between α-klotho and different metabolites of PAH were, more or less, randomly positive or negative and none reached statistical significance. To conclude, exposure to polycyclic aromatic hydrocarbons may result in reduced concentrations of α-klotho, an antiaging protein.

Association between serum carcinoembryonic antigen and cardiometabolic risks: Implication for cardiometabolic prevention

BACKGROUND

Serum carcinoembryonic antigen (CEA) is a biomarker commonly used to detect colorectal cancer. CEA levels are affected by many factors, including cardiometabolic diseases, such as cardiovascular diseases (CVDs) and diabetes. Cardiometabolic diseases and cancer share a similar pathological inflammatory pathway, which correlates with an unhealthy lifestyle. Hence, establishing an adequate CEA cut-off value might be a valuable reference for developing precision healthcare programs for cardiometabolic disease prevention. This study aimed to investigate the association between cardiometabolic risks and serum CEA and the underlying factors.

METHODS

A community-based, cross-sectional study was conducted between March and December 2021 on the western coast of Taiwan. Lifestyle data were assessed using a structured questionnaire. The cardiometabolic biomarkers, serum CEA, urine malondialdehyde, and 1-hydroxypyrene were quantified by the central laboratory of the collaborating hospital. Chi-square and binary multivariable logistic regression implemented in R version 4.0.2 were used to identify factors defining the risk of high serum CEA levels.

RESULTS

A total of 6,295 adult residents without cancer-related diseases completed the study. The mean age was 48.6 (SD = 16.4) years, 56% were female, 32% had metabolic syndrome, and 23% and 10% had CVDs and diabetes, respectively. Multivariate logistic regression showed that age ≥ 65 years, male sex, alcohol consumption, smoking, infrequent use of dental floss, fewer remaining teeth, CVDs, diabetes, and oxidative stress were significantly associated with serum CEA ≥ 3 ng/mL. The discriminatory performance of the area under the receiver operating characteristic curve was 0.75 (0.73-0.76), showing that this model was suitable for distinguishing high CEA levels.

CONCLUSION

Our findings highlight the importance of understanding cardiometabolic diseases, unhealthy lifestyles, and oxidative stress, which contribute to high serum CEA. This study demonstrates that CEA, a well-known tumor marker, can help the early detection and prevention of cardiometabolic diseases via personalized lifestyle modification.

Phthalate acid esters and polycyclic aromatic hydrocarbons concentrations with their determining factors among Chinese pregnant women: A focus on dietary patterns

BACKGROUND

Pregnant women are susceptible to adverse health effects associated with phthalate acid esters (PAEs) and polycyclic aromatic hydrocarbons (PAHs), and diet is a significant exposure source. Little is known about the contributions of dietary patterns during pregnancy to the exposure variability of these environmental contaminants.

OBJECTIVES

To identify dietary patterns in relation to PAEs and PAHs exposure in the Chinese pregnant population.

METHODS

Dietary data and urinary concentrations of environmental pollutants were obtained from 1190 pregnant women in the Tongji Birth Cohort (TJBC). PAEs and PAHs were measured in spot urine samples. Food intake was assessed using a food-frequency questionnaire. Dietary patterns were constructed by principal component analysis (PCA). Through PCA, we also extracted three chemical mixture scores that represent different co-exposure patterns of PAEs and PAHs. Multiple linear regression models were adopted to identify predictors of PAEs and PAHs exposure.

RESULTS

Four dietary patterns were identified by PCA that explained 44.9 % of the total variance of food intake. We found egg-dairy products pattern, whole grain-tuber crop pattern, and meat-aquatic products pattern were positively associated with specific pollutants exposure. In contrast, fruit-nut-vegetable pattern was negatively correlated with PAEs and PAHs exposure. Every SD increase in this pattern score was associated with 14.36 % reduced mono(2-ethyl-5-oxohexyl) phthalate (MEOHP) (95 % CI: -24.50 ~ -2.96, p-trend = 0.01), 10.86 % reduced 2-hydroxynaphthalene (2-OHNap) (95 % CI: -20.07 ~ -0.60, p-trend = 0.04), 19.35 % reduced 9-hydroxyphenanthrene (9-OHPhe) (95 % CI: -34.49 ~ -0.70, p-trend = 0.01), and 8.33 % reduced scores of PAHs group (95 % CI: -15.97 ~ -0.10, p-trend = 0.02). In addition, disposable tableware usage and passive smoking were suggested as potentially modifiable sources of PAEs and PAHs exposure, respectively.

CONCLUSION

Adhering to egg-dairy products pattern, whole grain-tuber crop pattern, and meat-aquatic products pattern may be related to increased PAEs and PAHs exposure, while following fruit-nut-vegetable pattern seems to correlate with a lower burden of such exposure.

The longitudinal biomonitoring of residents living near the waste incinerator of Turin: Polycyclic Aromatic Hydrocarbon metabolites after three years from the plant start-up

The waste-to-energy (WTE) incinerator plant located in the Turin area (Italy) started to recover energy from the combustion of municipal solid waste in 2013. A health surveillance program was implemented to evaluate the potential health effects on the population living near the plant. This program included a longitudinal biomonitoring to evaluate temporal changes of some environmental pollutants, including polycyclic aromatic hydrocarbons (PAHs), in residents living in areas near the Turin incinerator (exposed group, E) compared to those observed in subjects living far from the plant (not exposed group, NE). Ten monohydroxy-PAHs (OH-PAHs), consisting in the principal metabolites of naphthalene, fluorine, phenanthrene, and pyrene, were analyzed in urines collected from the E and NE subjects after one (T₁) and three years (T₂) of plant activity and compared with those determined in the same cohort established before the plant start-up (T₀). Spearman correlation analysis was undertaken to explore possible associations between OH-PAHs and personal characteristics, lifestyle variables, and dietary habits. A linear mixed model (LMM) approach was applied to determine temporal trends of OH-PAHs observed in the E and NE subjects and to evaluate possible differences in trend between the two groups. Temporal trends of OH-PAHs determined by LMM analysis demonstrated that, at all times, the E group had concentrations lower than those assessed in the NE group, all other conditions being equal. Moreover, no increase in OH-PAH concentrations was observed at T₁ and T₂ either in E or in NE group. Significant positive correlations were found between all OH-PAHs and smoking habits. Regarding variables associated to outdoor PAH exposure, residence near high traffic roads and daily time in traffic road was positively correlated with 1-hydroxynaphthalene and 1-hydroxypyrene, respectively. In conclusion, no impact of the WTE plant on exposure to PAHs was observed on the population living near the plant.

Urinary Biomarkers of Polycyclic Aromatic Hydrocarbons and Timing of Pubertal Development: The California PAH Study

BACKGROUND

Polycyclic aromatic hydrocarbons (PAHs) are endocrine-disrupting chemicals. Few studies have evaluated the association between pubertal development in girls and PAH exposures quantified by urinary biomarkers.

METHODS

We examined associations of urinary PAH metabolites with pubertal development in 358 girls 6-16 years of age from the San Francisco Bay Area enrolled in a prospective cohort from 2011 to 2013 and followed until 2020. Using baseline data, we assessed associations of urinary PAH metabolites with pubertal development stage. In prospective analyses limited to girls who at baseline had not yet started breast (N = 176) or pubic hair (N = 179) development or menstruation (N = 267), we used multivariable Cox proportional hazards regression to assess associations of urinary PAH metabolites with the onset of breast and pubic hair development, menstruation, and pubertal tempo (interval between the onset of breast development and menstruation).

RESULTS

We detected PAH metabolites in >98% of girls. In cross-sectional analyses using baseline data, PAH metabolites were not associated with the pubertal development stage. In prospective analyses, higher concentrations (≥ median) of some PAH metabolites were associated with two-fold higher odds of earlier breast development (2-hydroxy naphthalene, 1-hydroxy phenanthrene, summed hydroxy phenanthrenes) or pubic hair development (1-hydroxy naphthalene) among girls overweight at baseline (body mass index-for-age percentile ≥85) compared with nonoverweight girls with lower metabolites concentrations. PAH metabolites were not associated with age at menarche or pubertal tempo.

CONCLUSIONS

PAH exposures were widespread in our sample. Our results support the hypothesis that, in overweight girls, PAHs impact the timing of pubertal development, an important risk factor for breast cancer.

Polycyclic aromatic hydrocarbon exposure and DNA oxidative damage of workers in workshops of a petrochemical group

The petrochemical industry has promoted the development of economy, while polycyclic aromatic hydrocarbons (PAHs) produced by the industry become the threat for environment and humans. Data on human occupational exposure in petrochemical industry are limited. In the present study, urinary hydroxylated PAH metabolites (OH-PAHs) and a biomarker of DNA oxidative damage (8-hydroxy-2'-deoxyguanosine (8-OHdG)) were measured in 546 workers of a petrochemical group in Northeast China, to investigate PAH exposure and related potential health risk. The concentrations of ∑₉OH-PAH in all workers were 0.25-175 μg/g Cre with a median value of 4.41 μg/g Cre. Metabolites of naphthalene were the predominant compounds. The levels of PAH metabolites were significantly different for workers with different jobs, which were the highest for recycling workers (13.7 μg/g Cre) and the lowest for agency managers (5.12 μg/g Cre). Besides, higher levels of OH-PAHs were usually found in males and older workers. There was a dose-response relationship between levels of 8-OHdG and ∑₉OH-PAHs (p < 0.01). No difference was observed in concentrations of 8-OHdG for workers of different gender or ages, work history as well as noise. Furthermore, workers simultaneously exposed to other potential pollutants and higher levels of ∑₉OH-PAH had significantly higher levels of 8-OHdG compared with those in the corresponding subgroups. Our results suggested that exposure to PAHs or co-exposure to PAHs and potential toxics in the petrochemical plant may cause DNA damage. We call for more researches on the associations among noise, chemical pollution and oxidative stress to workers in the real working environment.

Predictors of urinary polycyclic aromatic hydrocarbon metabolites in girls from the San Francisco Bay Area

BACKGROUND

Polycyclic aromatic hydrocarbon (PAH) exposures from tobacco smoke, automobile exhaust, grilled or smoked meat and other sources are widespread and are a public health concern, as many are classified as probable carcinogens and suspected endocrine-disrupting chemicals. PAH exposures can be quantified using urinary biomarkers.

METHODS

Seven urinary metabolites of naphthalene, fluorene, phenanthrene, and pyrene were measured in two samples collected from girls aged 6-16 years from the San Francisco Bay Area. We used Spearman correlation coefficients (SCC) to assess correlations among metabolite concentrations (corrected for specific gravity) separately in first (n = 359) and last (N = 349) samples, and to assess consistency of measurements in samples collected up to 72 months apart. Using multivariable linear regression, we assessed variation in mean metabolites across categories of participant characteristics and potential outdoor, indoor, and dietary sources of PAH exposures.

RESULTS

The detection rate of PAH metabolites was high (4 metabolites in ≥98% of first samples; 5 metabolites in ≥95% of last samples). Correlations were moderate to strong between fluorene, phenanthrene and pyrene metabolites (SCC 0.43-0.82), but weaker between naphthalene and the other metabolites (SCC 0.18-0.36). SCC between metabolites in first and last samples ranged from 0.15 to 0.49. When classifying metabolite concentrations into tertiles based on single samples (first or last samples) vs. the average of the two samples, agreement was moderate to substantial (weighted kappa statistics 0.52-0.65). For specific metabolites, concentrations varied by age, race/ethnicity, and body mass index percentile, as well as by outdoor sources (season of sample collection, street traffic), indoor sources (heating with gas, cigarette smoke), and dietary sources (frequent use of grill, consumption of smoked meat or fish) of PAH exposures.

CONCLUSIONS

Urinary PAH exposure was widespread in girls aged 6-16 years and associated with several sources of exposure. Tertile classification of a single urine sample provides reliable PAH exposure ranking.

Exposure to polycyclic aromatic hydrocarbons and nicotine, and associations with sperm DNA fragmentation

Background

Tobacco smoking has been reported to cause DNA fragmentation and has been suggested to cause mutations in spermatozoa. These effects have been ascribed to the action of polycyclic aromatic hydrocarbons (PAH) present in the smoke. Simultaneously, DNA fragmentation has been associated with mutagenesis.

Objective

The aim of this study was to investigate whether levels of urinary biomarkers of PAH and nicotine exposure were associated with sperm DNA fragmentation.

Methods

In the urine of 381 men recruited from two cohorts of young men (17–21 years old) from the general Swedish population, the PAH metabolites 1‐hydroxypyrene and 2‐hydroxyphenanthrene, as well as the nicotine metabolite cotinine, were measured. The sperm DNA fragmentation index (DFI) was analysed using the sperm chromatin structure assay. Associations between the DFI, and PAH metabolite levels as continuous variables as well as in quartiles, were studied by general linear models adjusted for abstinence time. A similar analysis was carried out for cotinine levels, according to which the men were categorised as “non‐smoking” (n = 216) and “smoking” (n = 165).

Results

No association was found between levels of any of the three biomarkers and DFI, either as a continuous variable (p = 0.87–0.99), or when comparing the lowest and the highest quartiles (p = 0.11–0.61). The same was true for comparison of men categorised as non‐smoking or smoking (DFI 11.1% vs. 11.8%, p = 0.31).

Discussion

We found no evidence of PAH or nicotine exposure to be associated with DFI, which does not exclude that these exposures may have other effects on sperm DNA.

Conclusion

In these young men, levels of biomarkers of nicotine and PAH exposure were not associated with DFI.

Smokeless tobacco and cigarette smoking: chemical mechanisms and cancer prevention

Tobacco products present a deadly combination of nicotine addiction and carcinogen exposure resulting in millions of cancer deaths per year worldwide. A plethora of smokeless tobacco products lead to unacceptable exposure to multiple carcinogens, including the tobacco-specific nitrosamine N'-nitrosonornicotine, a likely cause of the commonly occurring oral cavity cancers observed particularly in South-East Asian countries. Cigarettes continue to deliver a large number of carcinogens, including tobacco-specific nitrosamines, polycyclic aromatic hydrocarbons and volatile organic compounds. The multiple carcinogens in cigarette smoke are responsible for the complex mutations observed in critical cancer genes. The exposure of smokeless tobacco users and smokers to carcinogens and toxicants can now be monitored by urinary and DNA adduct biomarkers that may be able to identify those individuals at highest risk of cancer so that effective cancer prevention interventions can be initiated. Regulation of the levels of carcinogens, toxicants and nicotine in tobacco products and evidence-based tobacco control efforts are now recognized as established pathways to preventing tobacco related cancer.

Factors Associated with Urinary 1-Hydroxypyrene and Malondialdehyde among Adults near a Petrochemical Factory: Implications for Sex and Lifestyle Modification

Background: The association between the biomarkers of environmental exposure, oxidative stress, and health-related behaviors in community residents living in an endemic viral hepatitis area and near petrochemical industrial complexes remains unclear. From a health promotion perspective, healthcare providers must know what to do for residents concerned about their health and living environment, especially for individual-level and modifiable risk factors. Therefore, we aimed to explore the factors associated with urinary 1-hydroxypyrene (1-OHP) and malondialdehyde (MDA). Methods: A community-based, cross-sectional study was conducted between July 2018 and February 2019 in western coastal Yunlin County, Taiwan. All participants lived within a 10 km radius of a large petrochemical complex and did not work in the factory. This study was conducted with the local hospital through annual community health screening. Biological samples were collected and biomarkers determined and quantified in the central laboratory of the collaborating hospital. Results: A total of 6335 adult residents completed the study. The mean age was 47.7 (SD = 16) years. Out of the total population, 56.4% were female, 30.1% had metabolic syndrome (MetS), and 16.8% and 14.3% had hepatitis B virus antigen (HBsAg) and hepatitis C virus antibody (anti-HCV) positivity, respectively. The median 1-OHP and MDA level was 0.11 and 0.9 μg/g creatinine with an interquartile range of 0.07–0.18, and 0.4–1.5, respectively. The MDA levels correlated with specific diseases. The multivariable ordinal logistic regression model revealed that female sex, smoking, betel nut use, HBsAg, and anti-HCV positivity were associated with higher 1-OHP levels. In men, MetS was associated with higher 1-OHP levels and regular exercise with lower 1-OHP levels. High MDA levels were associated with smoking, betel nut users, HBsAg, and anti-HCV positivity. Conclusions: The findings highlight the importance of initiating individualized health promotion programs for residents near petrochemical factories, especially for adults with substance-use and cardiometabolic risk factors. Furthermore, it is crucial to provide further treatment to patients with viral hepatitis.

The association between urinary metabolites of polycyclic aromatic hydrocarbons (PAHs) and cardiovascular diseases and blood pressure: a systematic review and meta-analysis of observational studies

Although epidemiological studies have discerned the association between polycyclic aromatic hydrocarbons (PAHs) exposure and hypertension and/or cardiovascular disease in the general population, the possible mechanisms for this association are not well understood. We sought to examine the association between urinary metabolites of PAHs and cardiovascular diseases (CVDs) and blood pressure in adults, by conducting a meta-analysis of observational studies. We searched PubMed, Scopus, Embase, and Web of science, up to July 2021, for observational studies that investigated the association between urinary metabolites of PAHs and CVDs and blood pressure in adults. Nine prospective studies, including 27,280 participants, were included. Based on overall pooled results, there was a significant positive association between all types of urinary metabolites of PAH and blood pressure (OR: 1.32; 95%, CI: 1.19 to 1.48, p < 0.0001) (I2 = 62.4%, p < 0.0001). There was no significant association between any urinary metabolite of PAH and CHD (OR: 0.93; 95%, CI: 0.83 to 1.03, p = 0.174) (I2 = 0%, p = 0.653). Overall, there was a significant positive association between all urinary metabolites of PAH and CVD (OR: 1.23; 95%, CI: 1.16 to 1.30, p < 0.0001) (I2 = 59.7%, p < 0.0001). The results of the present meta-analysis suggest that different metabolites PAHs are associated with an increased risk of CVD and HTN. Further studies, including randomized clinical trials, are needed to confirm the veracity of our findings.

Children's exposure to polycyclic aromatic hydrocarbons in the Valencian Region (Spain): Urinary levels, predictors of exposure and risk assessment

Polycyclic aromatic hydrocarbons (PAHs) are pollutants that are released into the environment during incomplete combustion of organic matter and which can have a negative effect on human health. PAHs enter the human body mostly through ingestion of food or inhalation of tobacco smoke. The purpose of the present study is to evaluate the internal levels of PAHs that children living in the Valencian Region (Spain) are exposed to. In total, we measured eleven biomarkers of exposure to naphthalene, fluorene, phenanthrene, pyrene, and benzo(a)pyrene in the urine of 566 children aged 5-12. The analytical method was based on a liquid-liquid extraction of the PAH metabolites from the urine samples, followed by their determination by liquid chromatography coupled to tandem mass spectrometry. In addition, we used a questionnaire to collect the socio-demographic characteristics and 72 h dietary recall information of the participants in our study. Overall, we detected PAH metabolites in more than 78% of the children, with the exception of 3-hydroxyfluorene and 3-hydroxybenzo(a)pyrene, which were found in less than 37% of the analyzed samples. The most abundant biomarker found was 2-hydroxynaphthalene, with a geometric mean of 10 ng·ml^-1. Reference values (RV₉₅) ranging from 0.11 (4-hydroxyphenanthrene) to 53 ng·ml^-1 (2-hydroxynaphthalene) in urine of Spanish children were derived from the present study. According to the statistical analysis, the factors that were significantly associated with the internal exposure to PAHs were province of residence, body mass index (BMI), children's age, consumption of plastic-wrapped food, and dietary habits. The estimated daily intakes in geometric mean terms ranged from 5 (fluorene) to 204 ng·kg-bw^-1·day^-1 (naphthalene). Risk assessment calculations showed higher hazard quotients and hazard indexes for children aged 5-8 than those aged 9-12, but all were below 1. In conclusion, no potential non-cancer health risk due to PAH exposure was observed in children living in Spain.

Biomonitoring of polycyclic aromatic hydrocarbons in the urine of lactating mothers: Urinary levels, association with lifestyle factors, and risk assessment

Polycyclic aromatic hydrocarbons (PAHs) are pollutants produced during incomplete combustion of organic matter and several industrial processes. Humans can be exposed to PAHs through ingestion of food, inhalation of tobacco smoke or polluted air, and dermal contact, causing immunologic, developmental, and reproductive problems. In the present research, eleven metabolites of PAHs were analyzed in the urine of 110 lactating women living in Spain (2015). PAH metabolites were extracted from the urine samples by liquid-liquid extraction and their determination was performed by liquid chromatography coupled to tandem mass spectrometry. In addition, information on lifestyle and dietary habits of the participants was collected using a questionnaire. All the PAH metabolites were detected in more than 70% of the samples, except for 3-hydroxybenzo(a)pyrene which was detected in less than 1% of the samples. The highest urinary levels were found for naphthalene metabolites, with geometric means of 0.8 (1-hydroxynaphthalene) and 7.1 ng ml^-1 (2-hydroxynaphthalene). The statistical analysis showed that smoking status, as well as the ingestion of certain food groups (vegetables, cereals, oils and fats, smoked fish and coffee), were the main influencing factors of exposure to PAHs. The estimated daily intake (EDI) was calculated for naphthalene, fluorene, phenanthrene, and pyrene, ranging from 6 to 1522 ng kg^-1·day^-1. The non-cancer risk associated to PAH exposure was estimated, showing hazard quotients (HQs) and hazard indexes (HIs) below 1. Therefore, it did not reveal a significant health risk for Spanish women due to PAH exposure.