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

Biomarkers of exposure to polycyclic aromatic hydrocarbons in urine of municipal police officers: impact of inhalation on total exposure

Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous environmental contaminants that adversely affect human health, mainly through their carcinogenic and mutagenic properties. Monitoring the exposure to PAHs of the inhabitants of air polluted regions is important because of the impact of these pollutants on human health. The aim of this study was to assess the exposure to PAHs of municipal police officers (non-smokers) living in three localities in the Czech Republic (strategically selected according to the level of air pollution) and determine how air pollution impacts personal exposure to PAHs via inhalation. Twenty PAHs were determined in the inhaled air collected from personal air samplers. Simultaneously, the total exposure to PAHs was investigated by evaluating the concentrations of 11 monohydroxylated polycyclic aromatic hydrocarbons (OH-PAHs) in urine samples. Despite the observed differences in the concentrations of PAHs in the air from the personal samplers between the three locations, no statistically significant differences were found in the concentrations of OH-PAHs in the urine samples. Outcomes of this study indicate that inhalation exposure is not the primary source of PAHs exposure for Czech municipal police officers, but that diet may also be an important contributor to total body burden. The levels of OH-PAHs found in urine of Czech municipal police officers were very similar to those found in the urine of the Czech mothers from our previous study. This study provided the data about the body burden of potentially occupationally exposed group that has not yet been studied in the Czech Republic.

Polycyclic aromatic hydrocarbon (PAH) exposure among European adults: Evidence from the HBM4EU aligned studies

Polycyclic aromatic hydrocarbons (PAHs) are persistent environmental pollutants with well-documented associations to adverse health effects, posing significant public health challenges across Europe. Human exposure to 13 urinary PAH metabolites was assessed in a harmonized cohort of European adults aged 20-39, representing diverse geographic regions across Europe: North (Iceland and Denmark), East (Poland and the Czech Republic), South (Croatia and Portugal), and West (France, Germany, Switzerland, and Luxembourg). This study aimed to achieve a unified understanding of PAH exposure by employing stringent participant selection criteria and harmonizing biomarker analyses by utilizing high-quality analytical protocols across multiple laboratories in Europe. Key findings revealed consistently elevated metabolite levels in smokers compared to non-smokers, with naphthalene metabolites dominating the profiles over phenanthrene and fluorene derivatives. Country-specific analyses highlighted Poland as having the highest naphthalene metabolite concentrations, while Luxembourg exhibited elevated pyrene metabolite levels. Urbanization influenced exposure, with slightly higher metabolite concentrations in town populations compared to rural areas. While sex-based stratification revealed no marked differences, gender emerged as a significant covariate in regression models, with women generally displaying higher exposure to naphthalene metabolites. Educational level further stratified exposure, with lower education correlating with increased PAH levels. Multivariate linear regression identified key exposure factors, including sampling season (i.e., summer, winter, autumn, and spring), dietary habits e.g., smoked foods, and proximity to smoke-prone environments. This dataset provides a significant baseline for evaluating the European Commission's Chemicals Strategy for Sustainability (CSS) and underscores the utility of harmonized human biomonitoring studies in informing targeted public health interventions.

Estimation of public exposure to PAH and environmental risks via wastewater-based epidemiology

The wastewater-based epidemiology (WBE) has the potential to monitor public health emergencies via the analysis of human urinary biomarkers in wastewater. This work proposes a novel approach utilizing WBE for the spatial and temporal evaluation of PAHs exposure using hydroxyl derivatives of PAHs. These are 1-hydroxynaphthalene, 2-hydroxynaphthalene, 2-hydroxyfluorene, 9-hydroxyfluorene, 9-hydroxyphenanthrene, 1-hydroxypyrene and 3-hydroxybenzo(a)pyrene. Most target markers were found at quantifiable concentrations in raw and treated wastewater. The total loads identified in raw sewage ranged from 88.33 g/day to 154.77 g/day during the summer period and from 137.66 g/day to 283.78 2 g/day during the winter period. The obtained results for the removal efficiencies of OH-PAHs indicate a seasonal dependency in their degradation. Removal efficiencies were higher in January compared to August. The results of the back calculations allowed to estimate that during the summer, on average, a resident of Krakow could absorb approximately 2.1 µg of the assessed OH-PAHs per day, while in winter, this value increased to 4.1 µg. This is close to the reported in the literature value that the total daily exposure to OH-PAHs is estimated at 3 µg/day. Moreover, the risk quotation (RQ) values on the base of acute and chronic data base for compounds present in effluents were calculated. The RQ values in January were relatively low, but in August the RQ values were higher, indicating a high concentration of effluent and nitrogen in summer as these compounds were removed in winter and summer. To the authors' knowledge, this is the first time wastewater profiling of OH-PAHs in wastewater for the evaluation of exposure to PAHs have been used, also their removal as well emission with effluent were determined.

Polycyclic Aromatic Hydrocarbons (PAHs) in the Environment: Occupational Exposure, Health Risks and Fertility Implications

Polycyclic aromatic hydrocarbons (PAHs) are a group of organic compounds with fused aromatic rings, primarily derived from combustion processes and environmental pollutants. This narrative review discusses the most relevant studies on PAHs, focusing on their sources, environmental and occupational exposure, and effects on human health, emphasizing their roles as carcinogenic, mutagenic, and teratogenic agents. The primary pathways for human exposure to PAHs are through the ingestion of contaminated food (mainly due to some food processing methods, such as smoking and high-temperature cooking techniques), the inhalation of ambient air, and the smoking of cigarettes. Coke oven workers are recognized as a high-risk occupational group for PAH exposure, highlighting the need for appropriate strategies to mitigate these risks and safeguard worker health. PAHs are metabolized into reactive intermediates in the body, which can lead to DNA damage and promote the development of various health conditions, particularly in environments with high exposure levels. Chronic PAH exposure has been linked to respiratory diseases, as well as cardiovascular problems and immune system suppression. Furthermore, this review underscores the significant impact of PAHs on reproductive health. The results of the reported studies suggest that both male and female fertility can be compromised due to oxidative stress, DNA damage, and endocrine disruption caused by PAH exposure. In males, PAHs impair sperm quality, while, in females, they disrupt ovarian function, potentially leading to infertility, miscarriage, and birth defects. Fetal exposure to PAHs is also associated with neurodevelopmental disorders. Given the extensive and detrimental health risks posed by PAHs, this review stresses the importance of stringent environmental regulations, occupational safety measures, and public health initiatives to mitigate exposure and safeguard reproductive and overall health.

Biomonitoring of Hydroxylated Polycyclic Aromatic Hydrocarbon Metabolites in Workers at a Waste-to-Energy Incinerator, Turin, Italy

This paper presents the results of the human biomonitoring of ten urinary OH-PAHs (hydroxylated polycyclic aromatic hydrocarbon) in a cohort of workers at an incinerator in Turin, Italy. Long-term exposure was assessed through repeated measurements at three time points: before the startup (T0), after 1 year (T1), and after 3 years (T2). Paired data were available for 26 subjects, seven administrative workers (AWs) and 19 plant workers (PWs). Short-term exposure was assessed by comparing start-end shift measurements. Due to the non-normal distribution of the data, the nonparametric Cuzick's test for trend and the Wilcoxon signed-rank test for paired samples were used. Neither the trend nor the T0-T2 comparison tests resulted in statistically significant outputs in the two groups (q-value > 0.05), even when controlling for smoking habits. In relation to PWs, some of the metabolites were higher at T2 with respect to T0, but no linear increase was found. Conversely, 1-OH-PYR (ng/g creatinine) showed lower median values at T1 (61.5) and T2 (67) compared to the baseline (151.3). Similarly, short-term comparisons yielded no significant results, with rather overlapping distributions of values. Overall, no significant increases in metabolite levels were detected as a result of occupational exposure in the incinerator workers considered. These findings align with previous results for metals and ambient air measurements.

Combating regional air pollution significantly enhance the photodegradation of atmospheric benzo(a)pyrene

Air pollution control strategies aim to reduce the levels of primary pollutants, but unexpectedly induce changes in atmospheric photochemistry. This may create favorable condition for the photodegradation of atmospheric Benzo(a) pyrene (BaP), leading to new environmental challenges because of the more toxic derivatives. Based on the field observations from 1998 to 2021 at Tsuen Wan (TW) and Central & Western District (CWD) sites in Hong Kong, Coupling detrended fluctuation analysis (CDFA) has been applied to quantitatively describe the photodegradation degree of BaP in real atmosphere. From the temporal evolution process, it has been discovered that BaP photodegradation exhibits a significant increase trend since 2019 in Hong Kong. Correlation analysis shows that degree of BaP photodegradation is positively correlated with factors (T, RH, hv, O3 and NO2/NOx), while is negatively correlated with factor (PM2.5/PM10). Due to the impact of sea salt aerosols, the effect of O3 and NO2 on BaP photodegradation at CWD site is less significant than that at TW site. Furthermore, the relative contribution of major atmospheric oxidants NO2 and O3 to BaP photodegradation in real atmosphere has been determined. The results suggest that contribution of NO2 to BaP photodegradation is greater than that of O3, and the contribution of O3 is gradually increasing in Hong Kong. This work has discovered a new environmental effect that may be caused by air pollution control strategies. New insights have significant implications for improving ecological risk assessment.

Polycyclic aromatic hydrocarbons (PAHs) in blood serum of adults living in high and low-traffic volume areas in Malaysia: A comparative cross-sectional study

Ambient polycyclic aromatic hydrocarbons (PAHs) originate predominantly from fuel combustion of motor vehicles and have the potential to affect human health. However, there is insufficient knowledge regarding serum PAHs health risks among the Malaysian population. This study aims to compare PAH concentrations, distributions, correlations, and health risks in 202 blood serum samples drawn from residents living in high-traffic volume areas (Kuala Lumpur) and low-traffic volume areas (Hulu Langat) in Malaysia. Solid phase extraction and gas chromatography-mass spectrometry (GC-MS) were employed to extract and analyze blood serum samples. Questionnaires were distributed to obtain sociodemographic and contributing factors of serum PAHs. The mean total PAHs concentration in serum of the Kuala Lumpur group was 54.44 ng g-1 lipids, double the Hulu Langat group's concentration (25.7 ng g-1 lipids). Indeno(1,2,3-cd)pyrene (IcP) and acenaphthene (ACP) feature the most and least abundant compounds in both study groups. The mean concentrations of IcP and ACP in the Kuala Lumpur and Hulu Langat groups were 26.8 vs 12.68 and 0.27 vs 0.14 ng g-1 lipids, respectively. High-molecular-weight PAHs (HMW-PAHs) composed 85% of serum total PAHs in both groups. Significant correlations were found (i) between the individual serum PAH congeners (p < 0.01) and (ii) between serum PAHs and total lipids (p < 0.01). According to the questionnaire data, high traffic volume and outdoor hobbies were the only contributory factors that confirmed significant relationships with serum PAHs (p < 0.001). Health risk assessment was computed using benzo(a)pyrene (BaP) equivalent (BaPeq) and demonstrated that the Kuala Lumpur group has twofold greater carcinogenic risk than the Hulu Langat group (16.11 vs 7.76 ng g-1 lipids). Our study reveals that traffic volumes notably impact serum PAH levels and general health among the Malaysian population.

The development of rapid immunoassays for the urinary analysis of 1-hydroxypyrene glucuronide facilitate both laboratory and on-site polycyclic aromatic hydrocarbon biomonitoring

Polycylic Aromatic Hydrocarbons (PAHs) are produced during the incomplete burning of organic materials. PAH sources include vehicle exhaust, tobacco smoke and waste incineration. Environmental and occupational exposures to PAHs are known to occur. Cancer is a significant endpoint of PAH exposure and several occupations associated with high PAH exposure have been classified by IARC as carcinogenic to humans (Group 1). Pyrene is a common component of PAH mixtures and metabolism of pyrene leads to the excretion of 1-hydroxypyrene glucuronide (1-OHPyrG) in urine. Laboratory measurement of urinary 1-OHPyrG is employed in occupational and environmental biomonitoring programmes. The production of an anti-1-OHPyrG monoclonal antibody would allow the development of a PAH biomonitoring ELISA facilitating large scale laboratory screening and routine testing. The development of a lateral flow immunoassay and the production of a field test (point of use test) would greatly increase the value of biomonitoring. A novel Lateral Flow has been developed which employs an anti-1-OHPyrG sheep monoclonal antibody (Mab) to capture the PAH metabolite. The captured metabolite is visualised through a second Mab raised against the Mab-1-OHPyrG immune complex. This sandwich assay provides a positive correlation between the assay signal and biomarker concentration. A Smartphone camera allows signal measurement and a carefully considered 'app' provides result interpretation and data analysis. Results are provided in an exposed/not-exposed format. Performance of the lateral flow was confirmed through a comparative study and field trial. The development of a lateral flow test provides "real-time" analysis to occupational health professionals. On-site screening allows the immediate confirmation of safe working practice, provides immediate reassurance to those involved in potentially hazardous activities and greatly increases the efficacy of biomonitoring.

Associations among urinary 1-hydroxypyrene level, oxidative stress, and high blood pressure: A panel study among elderly Koreans

Polycyclic aromatic hydrocarbons (PAHs) are environmental carcinogens. However, there is limited evidence for the relations between PAHs exposure and blood pressure (BP) with the mediating role of oxidative stress. Therefore, in this study, we evaluated relations among PAHs exposure, oxidative stress, and BP in the elderly population. We measured the levels of 1-hydroxypyrene (1-OHP), an indicator of PAHs exposure, and malondialdehyde (MDA), an oxidative stress marker, in urine samples repeatedly collected from 560 elderly persons aged ≥60 years, and then evaluated the relations among 1-OHP level, MDA level, and systolic or diastolic BP (SBP or DBP) measured on the day of urine collection. Urinary 1-OHP level was significantly associated with both MDA level (β = 0.19 and p < 0.0001) and BP (β = 1.72 and p < 0.0001 for SBP; and β = 1.24 and p < 0.0001 for DBP). Furthermore, urinary MDA level was also significantly associated with BP (β = 4.35 and p < 0.0001 for SBP; and β = 2.51 and p < 0.0001 for DBP). The trend for the change of SBP and DBP by 1-OHP quartile was more apparent in the elderly female participants (ptrend<0.0001 for SBP; and ptrend<0.0001 for DBP) compared with the elderly male participants (ptrend = 0.8351 for SBP; and ptrend = 0.3736 for DBP). To explore the mediating role of oxidative stress in the relation between 1-OHP level and SBP or DBP, we repeated these analyses after adjustment for the MDA levels. The increase in BP by 1-OHP exposure was largely mediated by the production of MDA (96.3% for SBP and 94.7% for DBP). These results revealed that PAHs exposure may increase BP through the mediation of oxidative stress.

Online SPE-LC-MS-MS method for eight hydroxylated metabolites of polycyclic aromatic hydrocarbons in urine and determination of optimal sampling time after firefighter training

Polycyclic aromatic compounds (PAHs) are formed during incomplete combustion and firefighters are inadvertently at risk of being exposed to these and other hazardous compounds. Exposure to PAHs is often estimated by measuring their hydroxylated metabolites (OH-PAH) in urine. Here, an online-SPE LC-MS-MS method was set up for eight OH-PAHs thus increasing sample throughput and minimizing manual handling. The method was validated over a 5-month period and showed good reproducibility with intra- and inter-day variation of 2.4-8.1 % and 1.6-6.5 %, respectively, of low-level samples and accuracy (91.6-104.8 %) for a standard reference material. The method was applied to urine samples from conscripts training to become firefighters to determine the optimal sampling time for this training activity before a large intervention study. In total, six conscripts sampled urine 6-8 times over a 40-hr period during a 3-day training course. All eight metabolites were detected in ≥ 97 % of the samples and showed peak excretion 4-6 hrs after the training corresponding to 8-10 hrs after first exposure. Samples taken the morning after the exercise contained low levels of most metabolites. Consequently, 4-6 hrs post exposure is recommended as the optimal sampling time for quantification of PAH exposure and monitoring of potential differences in exposure.

Review of environmental airborne pyrene/benzo[a]pyrene levels from industrial emissions for the improvement of 1-hydroxypyrene biomonitoring interpretation

Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous pollutants of significant public health concern, with several that are highly toxic to humans, including some proven or suspected carcinogens. To account for the high variability of PAH mixtures encountered in occupational settings, adjusting urinary 1-hydroxypyrene (1-OHP) levels by the total airborne pyrene (PyrT)/benzo[a]pyrene (BaP) ratio is essential for human biomonitoring (HBM). Given the complexity and cost of systematically monitoring atmospheric levels, alternative approaches to simultaneous airborne and HBM are required. The aim of this review was to catalog airborne PyrT/BaP ratios measured during different industrial activities and recommend 1-OHP-dedicated biological guidance values (BGV). A literature search was conducted. Seventy-one studies were included, with 5619 samples pertaining to 15 industrial sectors, 79 emission processes, and 213 occupational activities. This review summarized more than 40 years of data from almost 20 countries and highlighted the diversity and evolution of PAH emissions. PyrT/BaP ratios were highly variable, ranging from 0.8 in coke production to nearly 40 in tire and rubber production. A single PyrT/BaP value cannot apply to all occupational contexts, raising the question of the relevance of defining a single biological limit value for 1-OHP in industrial sectors where the PyrT/BaP ratio variability is high. Based upon the inventory, a practical approach is proposed for systematic PAH exposure and risk assessment, with a simple frame to follow based upon specific 1-OHP BGVs depending upon the occupational context and setup of a free PAH HBM interactive tool.

The effects and potential mechanisms of essential metals on the associations of polycyclic aromatic hydrocarbons with blood cell-based inflammation markers

BACKGROUND

Polycyclic aromatic hydrocarbons (PAHs) are well-acknowledged pro-inflammatory chemicals, but their associations with blood cell-based inflammatory biomarkers need further investigation. Moreover, the effects and mechanisms of essential metals on PAH-related inflammation remain poorly understood.

OBJECTS

To elucidate the associations of PAHs on inflammatory biomarkers, as well as the effects and mechanisms of essential metals on these associations.

METHODS

A cross-sectional study was conducted on 1388 coke oven workers. We analyzed the modification effects of key essential metal(s) on PAHs-inflammatory biomarkers associations. To explore the possible mechanisms from an inflammation perspective, we performed a bioinformatic analysis on the genes of PAHs and essential metals obtained from the Comparative Toxicogenomics Database (CTD) and performed a mediation analysis.

RESULTS

We observed associations of PAHs and essential metals with lymphocyte-to-monocyte ratio (LMR) (P < 0.05). PAH mixtures were inversely associated with LMR (βQGC-index = -0.18, P < 0.001), with 1-hydroxypyrene (1-OH-Pyr) being the most prominent contributor (weight = 63.37%), whereas a positive association between essential metal mixtures and LMR was observed (βQGC-index = 0.14, P < 0.001), with tin being the most significant contributor (weight = 51.61%). An inverse association of 1-OH-Pyr with LMR was weakened by increased tin exposure (P < 0.05). The CTD database showed that PAHs and tin compounds co-regulated 22 inflammation-associated genes, but they regulated most genes in opposite directions. Further identified the involvement of oxidative stress and mediation analysis showed that the mediation effect of 8-hydroxydeoxyguanosine (8-OHdG) on 1-OH-Pyr-LMR association presented heterogeneity between low and high tin tertile groups (I2 = 37.84%).

CONCLUSION

1-OH-Pyr and tin were significantly associated with LMR. Modification effects indicated that the inverse association of 1-OH-Pyr with LMR was mitigated with an increase in tin. The mediation effect of 8-OHdG on the inverse association of 1-OH-Pyr with LMR may be partially dependent on tin.

Methods to assess dermal exposures in occupational settings: a scoping review

OBJECTIVES

The dermal exposure route is expected to become increasingly significant relative to total worker exposure as inhalational exposure limits continue to decrease. However, standardization of occupational exposure assessment methods and scientific consensus are needed. This is the first scoping review mapping the literature across all dermal exposure assessment methods and their targeted substances/chemicals in occupational settings.

METHODS

Eligibility criteria broadly included studies reporting any noninvasive dermal exposure assessment method in an occupational setting. The literature search (Web of Science and MEDLINE) was restricted to peer-reviewed, primary literature published in the last 20 years (2002-2022). Titles/abstracts were dual independently screened. Data charting was performed by a single reviewer using standard template. All stages were pilot tested. The JBI (formerly, the Joanna Briggs Institute) scoping review methods and PRISMA-ScR checklist (Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews) were used.

RESULTS

In total, 493 articles were data charted and categorized by 4 study types: methods development (22%), exposure assessment (51%), health outcomes (21%), and controls assessment (6%). Fourteen types of dermal exposure assessment methods were charted with biomarkers (51%), dosimeters (21%), and qualitative assessments such as questionnaires or surveys (17%) most common. Seventeen different chemicals/substances were charted; pesticides (28%) and polycyclic aromatic hydrocarbons (PAHs) (22%) associated with crude oil products and combustion were most common. Mapping between substances and exposure assessment method categories, pesticide dosimeters (11%), and PAH biomarker studies (14%) were most reported. Literature gaps were identified for cleaning agents, hair dyes, glycol ether, N,N-dimethylformamide/N-methyl-2-pyrrolidone, dioxins, and bisphenol A.

CONCLUSIONS

To foster scientific consensus, standardization across study reporting is needed for describing: (i) exposure assessment methods used, (ii) worker tasking/conditions, (iii) targeted substances and substance state, and (iv) targeted exposure routes. Overall, this review categorizes, maps, and defines the scope of literature for occupational dermal exposure assessment methods.

Association between polycyclic aromatic hydrocarbon exposure and liver function: The mediating roles of inflammation and oxidative stress

Polycyclic aromatic hydrocarbon (PAH) exposure has been associated with adverse health effects, and accumulating evidence suggests that PAH exposure may impair liver function. However, the underlying mechanisms linking PAH exposure and liver function impairment remain unclear. This study aimed to explore the association between PAH exposure and liver function biomarkers, and the mediating effects of inflammation and oxidative stress. The cross-sectional study included 155 adults and their urinary PAH metabolites (OH-PAHs) were determined, and eight liver function biomarkers were measured in paired serum samples. A comprehensive statistical analysis investigated the linear, non-linear, individual, and joint effects of the association between urinary OH-PAHs and liver function biomarkers. The results indicated significant positive associations between urinary OH-PAH concentrations and liver function biomarker levels, suggesting that PAH exposure may adversely affect liver function. 2-hydroxyfluorene was identified as the individual metabolite contributing significantly to elevated gamma-glutamyl transferase levels. Further stratification by gender revealed that this association is more pronounced in males. Moreover, we observed significant mediation effects of the oxidative stress biomarker 8-hydroxy-2'-deoxyguanosine and the inflammatory biomarkers C-reactive protein and white blood cell count on this association. The physiological responses triggered by PAH exposure are mediated by inflammation, which serves as a link between oxidative stress, cellular injury, and elevated liver enzyme levels. The results demonstrated that increased inflammation and oxidative stress mediated the association between increased urinary OH-PAHs and elevated liver function biomarkers. The results contribute to a better understanding of the potential mechanisms underlying PAH exposure's hepatotoxic effects.

Effects of polycyclic aromatic hydrocarbons (PAHs) on pregnancy, placenta, and placental trophoblasts

Polycyclic aromatic hydrocarbons (PAHs) are a group of persistent organic pollutants that are carcinogenic, mutagenic, endocrine-toxic, and immunotoxic. PAHs can be found in maternal and fetal blood and in the placenta during pregnancy. They may thus affect placental and fetal development. Therefore, the exposure levels and toxic effects of PAHs in the placenta deserve further study and discussion. This review aims to summarize current knowledge on the effects of PAHs and their metabolites on pregnancy and birth outcomes and on placental trophoblast cells. A growing number of epidemiological studies detected PAH-DNA adducts as well as the 16 high-priority PAHs in the human placenta and showed that placental PAH exposure is associated with adverse fetal outcomes. Trophoblasts are important cells in the placenta and are involved in placental development and function. In vitro studies have shown that exposure to either PAH mixtures, benzo(a)pyrene (BaP) or BaP metabolite benzo(a)pyrene-7,8-dihydrodiol-9,10-epoxide (BPDE) affected trophoblast cell viability, differentiation, migration, and invasion through various signaling pathways. Furthermore, similar effects of BPDE on trophoblast cells could also be observed in BaP-treated mouse models and were related to miscarriage. Although the current data show that PAHs may affect placental trophoblast cells and pregnancy outcomes, further studies (population studies, in vitro studies, and animal studies) are necessary to show the specific effects of different PAHs on placental trophoblasts and pregnancy outcomes.

Impact of diesel exhaust exposure on urinary 1-hydroxypyrene in underground salt and potash workers

BACKGROUND

Diesel engine exhaust (DEE) and some of the polycyclic aromatic hydrocarbons (PAH) it contains are carcinogenic to humans (for example benzo(a)pyrene) and can cause lung cancer in workers. The objective of this study was to assess exposures to DEE and its component PAH and the potential associations between these two health hazards in a salt and potash mining population.

METHODS

Between 2017 and 2019, 1003 underground workers (mining n = 801, maintenance n = 202) and 243 above-ground facility workers from two German mines participated. Personal exposure to DEE was assessed in air as elemental carbon for diesel particulate matter (EC-DPM), whereas exposure to PAH was assessed in pre- and post-shift urine samples in terms of 1-hydroxypyrene (1-OHP). Associations between EC-DPM and 1-OHP were studied using linear regression models.

RESULTS

The highest EC-DPM exposures were measured in mining workers (median 0.06 mg/m³) followed by workers in the maintenance (0.03 mg/m³) and facility areas (<0.02 mg/m³). Exposures above the current German occupational threshold level of 0.05 mg/m³ were observed in 56%, 17%, and 5% of mining, maintenance and facility workers, respectively. 1-OHP increased statistically significantly across a work shift in underground workers but not in facility workers. Regression analyses revealed an increase of post-shift 1-OHP by almost 80% in mining and 40% in maintenance compared with facility workers. 1-OHP increased with increasing EC-DPM among underground workers. However, internal exposure of 1-OHP mainly remained at levels similar to those of the German general population in more than 90% of the urine samples.

CONCLUSIONS

While exposures to DEE above the current German OEL for EC-DPM are quite common in the studied population of underground salt and potash miners (39.5% overall), urinary concentrations of 1-OHP did not reflect these findings.