Association between exposure to polycyclic aromatic hydrocarbons and endometriosis: data from the NHANES 2001-2006

Aim

To evaluate the association between urinary polycyclic aromatic hydrocarbon (PAH) metabolites and the risk of endometriosis.

Methods

This cross-sectional study obtained data on women aged 20-54 years from the National Health and Nutrition Examination Survey (NHANES) 2001-2006. The weighted multivariate logistic regression model was established to assess the association between the eight urinary PAH metabolites and the risk of endometriosis. In this multivariate analysis, the eight urinary PAH metabolites were adjusted with urinary creatinine, and were divided into three groups according to tertiles: Tertile 1, Tertile 2 and Tertile 3. To evaluate the overall association of mixed PAH metabolites with endometriosis, the Bayesian kernel machine regression (BKMR) model was applied.

Results

Totally 1,291 women were included, of which 90 (6.97%) had endometriosis and 1,201 (93.03%) did not have endometriosis. After adjusting for age, race, smoking, age at menarche, hysterectomy, ovary removed, female hormone use, and menopause, compared with the Tertile 1 group, the Tertile 2 and Tertile 3 groups of all PAH metabolites demonstrated no significant risk of endometriosis. A positive tendency was found between mixed PAH metabolites and endometriosis when all the metabolites were at their 60th percentile levels or above compared with their median levels. When all the other metabolites were fixed at their median levels, 1-hydroxynaphthalene was positively correlated with endometriosis. Potential interactions existed between 1-hydroxynaphthalene and 2-hydroxynaphthalene and between 2-hydroxyfluorene and 3-hydroxyfluorene.

Conclusion

No significant association was found between individual PAH metabolites and endometriosis. A positive association existed between mixed PAH metabolites and the risk of endometriosis.

The Use of Human Biomonitoring to Assess Occupational Exposure to PAHs in Europe: A Comprehensive Review

Polycyclic aromatic hydrocarbons (PAHs) are among the chemicals with proven impact on workers' health. The use of human biomonitoring (HBM) to assess occupational exposure to PAHs has become more common in recent years, but the data generated need an overall view to make them more usable by regulators and policymakers. This comprehensive review, developed under the Human Biomonitoring for Europe (HBM4EU) Initiative, was based on the literature available from 2008-2022, aiming to present and discuss the information on occupational exposure to PAHs, in order to identify the strengths and limitations of exposure and effect biomarkers and the knowledge needs for regulation in the workplace. The most frequently used exposure biomarker is urinary 1-hydroxypyrene (1-OH-PYR), a metabolite of pyrene. As effect biomarkers, those based on the measurement of oxidative stress (urinary 8-oxo-dG adducts) and genotoxicity (blood DNA strand-breaks) are the most common. Overall, a need to advance new harmonized approaches both in data and sample collection and in the use of appropriate biomarkers in occupational studies to obtain reliable and comparable data on PAH exposure in different industrial sectors, was noted. Moreover, the use of effect biomarkers can assist to identify work environments or activities of high risk, thus enabling preventive risk mitigation and management measures.

Evaluation of respiratory function and biomarkers of exposure to mixtures of pollutants in brick-kilns workers from a marginalized urban area in Mexico

Brick-kilns are polluted environments due to the use of low-quality technologies and fuels, which generates black fumes with a large number of pollutants. The objective of this research was to analyze environmental exposure and biomarkers of exposure to polycyclic aromatic hydrocarbons, metals, and respiratory health in brickmakers to assess the baseline state of contamination in a brick-kiln area of San Luis Potosi, Mexico. Lead was quantified in soil and particulate matter of 2.5 μm (PM_2.5) and 10 μm (PM₁₀) in brick-kiln areas. In brickmakers, lead was evaluated in whole blood and 10 hydroxylated metabolites of polycyclic aromatic hydrocarbons were determined in urine. Respiratory health was assessed by spirometry, exhaled breath condensate, and a COPD-PS questionnaire. Data association was performed by Spearman correlation. Environmental concentrations and biomarkers of exposure are presented as medians, for lead, it was 60.4 mg/kg, for PM10, it was 2663.1 μg/m³, and for PM2.5, it was 166.6 μg/m³. For blood lead, it was 1.06 μg/dL, and the summed concentration of OH-PAHs in urine was 16.1 μg/L. Spirometry values were 2.8 ± 0.6 L and 2.9 ± 1.3 L/s FEV1 and FEV 25-75 respectively. The correlation results indicate that the older the age of the workers is and the extensive period they have been working, their lung function is affected the most. The health vulnerability present in these occupational activities is high, so it is necessary to make visible, address these economic activities in Mexico, and apply surveillance systems based on the health of the worker.

Associations of Bitumen Fumes with Lymphocyte Subsets and Cytokines Expression in the Peripheral Blood of Exposed Workers

OBJECTIVES

The present study aimed to investigate the distribution of lymphocyte subsets and cytokines expression in the peripheral blood of bitumen fumes-exposed workers.

METHODS

In this study, 129 workers from molding and roasting workshops were recruited as the exposed group and 99 office and quality inspection staff were chosen as the control. The polycyclic aromatic hydrocarbons (PAHs) levels of bitumen fumes in individual and fixed-point air samples and the urinary levels of 1-hydroxypyrene (1-OH-P), 1-hydroxynaphthols (1-OH-N) and 2-hydroxynaphthols (2-OH-N) in workers were measured using High Performance Liquid Chromatography. The lymphocyte subsets and serum cytokines concentrations were analyzed by flow cytometry and cytometric bead array, respectively.

RESULTS

The median values of PAHs were 0.08 mg/m3 for permissible concentration-time weighted average and 0.12 mg/m3 for permissible concentration-short term exposure (PC-STEL) in molding and roasting workshops, which were higher than that in the control area (< 0.01 mg/m3). Multivariate linear regression models were used to adjust for influential covariates, including age, gender, work age, smoking status, and alcohol consumptions. After adjusting for these covariates, we compared levels of urinary PAHs metabolites, the percentages of lymphocyte subsets, and serum cytokines concentrations between the two groups. The 1-OH-P, 1-OH-N, and 2-OH-N levels in the urine of bitumen fumes exposed workers were significantly higher than that in the controls (P < 0.05). Compared with the control group, the percentage of the natural killer (NK) cell (CD56+ cell) was significantly increased in the exposed group (P < 0.001). There was a significant decrease in the percentages of CD3+ T cell, CD4+ T cell, and CD8+ T cell in the exposed group compared to the control (P < 0.001). The serum levels of interleukin-1β (IL-1β) and IL-6 in bitumen fumes exposed workers were significantly higher than that of the controls (P < 0.05). Moreover, positive correlations were observed between the serum levels of IL-1β, IL-6, and urinary 1-OH-P levels in bitumen fumes-exposed workers, respectively (P < 0.05). There were no significant differences in the serum levels of IL-8, tumor necrosis factor-α (TNF-α), macrophage inflammatory protein-1β (MIP-1β) and monocyte chemotactic protein-1 (MCP-1) between the exposed group and the control group (P > 0.05).

CONCLUSION

Our study suggested that low dose of bitumen fumes exposure could decrease the percentage of T cell, increase the percentage of NK cell and stimulate the release of serum IL-1β and IL-6 in the peripheral blood of exposed workers. The serum levels of IL-1β and IL-6 were positive correlated with the urinary 1-OH-P levels in bitumen fumes exposed workers. These results may inform the search for potential effective biomarkers and provide evidences for early health monitoring in workers occupationally exposed to bitumen fumes.

The impact on T-regulatory cell related immune responses in rural women exposed to polycyclic aromatic hydrocarbons (PAHs) in household air pollution in Gansu, China: A pilot investigation

Previous studies found associations between impairments of immune functions and exposure to polycyclic aromatic hydrocarbons (PAHs) in ambient air pollution in the U. S. and China. However, the results remain inconclusive due to the limitations of these studies. In this study, we aimed to examine the direction and magnitude of immune changes related to PAH exposure from household air pollution among rural women living in Gansu, China. Healthy village women (n = 34) were recruited and enrolled in the study. Questionnaires were administered. Blood and urine samples were collected and analyzed during non-heating (September 2017, "summer") and heating (January 2018, "winter") seasons. Urinary 1-hydroxypyrene (1-OHP) was quantified as the biomarker of PAH exposure. To evaluate Treg cell related immune functions, we examined immunoglobulin E (IgE), percent of T-regulatory (Treg) cells, and gene expression of following: forkhead box transcription factor 3 (Foxp3), transforming growth factor-β (TGF-β), interleukin 10 (IL-10), and interleukin 35 (IL-35), composed of interleukin-12 alpha (IL-12α) and Epstein-Barr-virus-induced gene 3 (EBi3). Urinary 8-hydroxy-2-deoxyguanosine (8-OHdG) was measured to evaluate oxidative DNA damage. The results showed that the concentration of 1-OHP increased from 0.90 to 17.4 μmol mol-Cr ^-1 from summer to winter (p < 0.001). Meanwhile, average percent of Treg cells decreased from 5.01% to 1.15% (p < 0.001); IgE and mRNA expressions of Foxp3, TGF-β, IL-10, IL-12α and EBi3 all significantly decreased (p < 0.001); Urinary 8-OHdG increased from 12.7 to 30.3 ng mg-Cr ^-1 (p < 0.001). The changes in 8-OHdG, Foxp3 and TGF-β were significantly associated with the increase of 1-OHP. The results suggested that we observed a substantial increase of PAH exposure in winter, which was significantly associated with the repression on Treg cell function and oxidative DNA damage. Exposure to PAHs in household air pollution possibly induced immune impairments among rural women in northwest China.

Exposure to polycyclic aromatic hydrocarbons in women living in the Chinese cities of BaoDing and Dalian revealed by hair analysis

Polycyclic aromatic hydrocarbons (PAH) are produced from incomplete combustion of organic matter and released as environmental contaminants from activities such as transports, wood combustion, coal-fired power plants. In numerous urban areas worldwide, the levels of PAH exposure are considered critical regarding public health issues. The possibility to detect PAH and PAH metabolites biologically incorporated in human hair was demonstrated and proposed as biomarkers of exposure. Nevertheless, the possibility to distinguish different levels of exposure between different populations is still needed to validate the relevance of hair analysis in epidemiological studies. In this work, hair samples were collected from 204 women from two cities in China based on one year Air Quality Index history from governmental data (Baoding as polluted city and Dalian less polluted city). 8 out of the 15 parent PAH and 7 out of the 56 metabolites analyzed in this study were detected in all the samples. The highest concentrations in hair were observed for phenanthrene (4.2 to 889 pg/mg) > fluoranthene (1.05 to 204 pg/mg) > pyrene (3.2 to 124 pg/mg) for parent PAH, and for 9-OH-fluorene (0.04 to 1.78 pg/mg) > 2-OH-naphthalene (0.68 to 811 pg/mg) > 1-OH-anthracene (0.24 to 10.9 pg/mg) for metabolites. 14 parent PAH and 15 metabolites presented a significantly higher concentration in the hair samples collected from Baoding, as compared to Dalian. The median concentration of parent PAH was from 1.5 to 2.8 times higher in the hair of the subjects from Baoding than in subjects from Dalian and that of PAH metabolites was from 1 to 2.3 times higher. The study of inter-chemical associations revealed similarities and differences between the two areas, suggesting common and different sources of exposure depending on PAH respectively. The results confirmed the relevance of hair analysis to identify qualitative and quantitative differences in PAH exposure between populations from different areas. This study is the first one to investigate both parent PAH and their metabolites in a biological matrix.

Associations between sperm quality, DNA damage, and CYP1A1, GSTT1 and GSTM1 polymorphisms with 1-hydroxypyrene urinary levels in men occupationally exposed to polycyclic aromatic hydrocarbons

PURPOSE

During recent decades, several reports have suggested a decrease in semen quality and DNA damage due in part to environmental toxicants and industrial chemicals. Among these xenobiotics, polycyclic aromatic hydrocarbons (PAHs) are of particular concern because of their remarkable mutagenic and carcinogenic properties and because several experimental and epidemiological studies have reported adverse effects of PAHs on male reproductive health and DNA structure. The aim of the study was to evaluate the association between 1-hydroxypyrene (1-OHP) urinary levels and sperm quality, DNA damage and the frequency of CYP1A1, GSTT1, and GSTM1 polymorphisms.

METHODS

Semen, urine and blood samples were taken for sperm-quality assessment, 1-OHP urinary level measurement, DNA damage evaluation and polymorphism frequency analysis of three genes implicated in PAH metabolism in a total of 70 Mexican subjects exposed and nonexposed to PAHs.

RESULTS

A significant decrease in sperm quality and increased DNA damage were registered in occupationally exposed volunteers. Polymorphisms modified the 1-OHP urinary levels; however, no associations were found between them. Inverse associations were registered between the sperm concentration/mL and 1-OHP levels and between tail lengths and the GSMT1 null genotype.

CONCLUSIONS

Our data showed an inverse association between 1-OHP urinary levels and both sperm quality and the DNA integrity. Additionally, the heterozygote variants of CYP1A1-m1 and CYP1A1-m2 significantly increased the urinary excretion of 1-OHP, and the GSTM1 null variant was inversely associated with the comet parameters evaluated.

Influence on serum asymmetric dimethylarginine (ADMA) concentrations of human paraoxonase 1 polymorphism (Q192R) and exposure to polycyclic aromatic hydrocarbons (PAHs) in Mexican women, a gene-environment interaction

It has been demonstrated that Cardiovascular Diseases (CVD) are a consequence of the combination of genetic and environmental factors and/or the interaction between them. Therefore, the aim of this study was to evaluate the impact of polycyclic aromatic hydrocarbon (PAHs) exposure and PON1 Q192R polymorphism (genetic susceptibility) on serum asymmetric dimethylarginine (ADMA) levels in Mexican women (n = 206). Urinary 1-hydroxypyrene concentrations (1-OHP; exposure biomarker for PAHs) were quantified using a high-performance liquid chromatography technique, PON1 Q192R polymorphism was genotyped using TaqMan probes and serum ADMA concentrations were evaluated using a commercially available ELISA kit. Urinary 1-OHP levels detected in this study ranged from 0.07 to 9.37 μmol/mol of creatinine (0.13-18.0 μg/g of creatinine). Regarding allele frequency (PON1 Q192R polymorphism), the 192Q-allele frequency was 0.43 and for the 192R-allele it was 0.57. In relation to serum ADMA levels, the levels ranged from 0.06 to 1.46 μmol/L. Moreover, multiple linear regression analysis was performed and associations between urinary 1-OHP levels (β = 0.05, p = 0.002), PON1 Q192R polymorphism (β = 0.04, p = 0.003) and serum ADMA concentrations were found. Besides, an interaction (gene-environment interaction) of both independent variables (1-OHP and PON1 polymorphism) on serum ADMA levels was found (β = 0.04, p = 0.02) in the constructed multiple linear model. Therefore, according to the significance of this research, it is necessary to execute health programs to reduce cardiovascular risk in the assessed population.