Non-carcinogenic Polycyclic Aromatic Hydrocarbons Research Articles

Assessment of Polycyclic Aromatic Hydrocarbons and Heavy Metals Contamination in the Egyptian Smoked Herring (Clupea harengus)

Polycyclic aromatic hydrocarbons (PAHs) and heavy metals can influence smoked fish quality and safety. Concentrations of 16 PAHs and heavy metals from smoked herring from three governorates in Egypt [Al-Behera (CF1), Cairo (CF2), and Alexandria (CF3)] were investigated. The mean concentration of individual PAHs ranged from 0.0007 μg/g of benzo[g,h,i]perylene (BgP) in Cairo to 0.3446 μg/g of benzo[a]anthracene (BaA) in Alexandria with the highest concentrations of the total PAHs found in Alexandria, followed by Al-Behera and then Cairo. Fluorene at CF3 had the highest mean concentration (0.2856 μg/g) which comprised 17.86% of total noncarcinogenic PAHs. Among the genotoxic PAHs (PAH8), BgP showed the lowest mean concentration (0.0007 μg/g) in Alexandria which accounted for 0.2% of ΣPAHs. Benz(a)anthracene had the highest mean values (0.3446 μg/g, 21.55%), followed by chrysene (0.2644 μg/g, 16.54%) at CF3. Mean concentrations of benzo(a)pyrene (BaP) were 0.0186, 0.0045, and 0.0254 μg/g for Al-Behera, Cairo, and Alexandria, respectively. The mean concentrations for BaP were higher than the maximum acceptable levels (5 μg/kg) established by European Union, which were classified as carcinogen. Among heavy metals, lead had the highest concentration (6.96 μg/g), which was higher than the maximum permissible levels set by World Health Organization, while nickel and arsenic were not detected.

Contamination, health risk, mineralogical and morphological status of street dusts- case study: Erbil metropolis, Kurdistan Region-Iraq

Street dusts contamination by heavy metals (HMs) and polycyclic aromatic hydrocarbons (PAHs), their mineralogical and morphological properties were investigated in Erbil metropolis. A total of 43 soil and street dust samples were collected and analyzed, and SPSS, ImageJ, X-powder and positive matrix factorization (PMF) software were used for data analyzing. Results showed the role of geology in mineralogical status of dusts. Based on ImageJ software processing, dust particles with diameters below 10 μm and low circularity and roundness were dominant. The enrichments for Hg, Cu, Pb and Zn contents were observed in compare with their calculated local geochemical baselines and geoaccumulation index, while, Ni, Co and Cr were categorized as particularly unpolluted. However, Hg, Cu and Pb showed the highest ecological risk (Eji) values among the studied elements, and 25.80%, 25.80% and 12.90% of the samples were classified as very high, moderate and considerable potential ecological risks, respectively. Hazard index (HI) followed the decreasing order of Pb > Cr > Cu > Ni > Hg > Zn > Co, and ingestion was the main exposure route particularly for children. The concentrations of individual PAHs ranged from 1.06 to 1000 ng/g, with the dominance of 3 and 4-ring compounds. Also, non-carcinogenic PAHs concentrations were higher than carcinogenic compounds and toxic equivalents (TEQs) ranged from 22.30 to 246.92 ng/g, with a max value in Northern industrial zone. Finally, source identification using multivariate statistics and PMF introduced three main PAHs and HMs sources in the study area including geogenic, traffic and industries, and incinerators (mainly for medical wastes).

Polycyclic Aromatic Hydrocarbons in Different Varieties of Rice (Oryza sativa) from Yobe State, Nigeria

The present study determined the levels of sixteen polycyclic aromatic hydrocarbons (PAHs) in rice (Oryza Sativa) samples from six agricultural locations in Bade and Karasuwa Local Government Areas, Yobe State, Nigeria. Four varieties of rice (FARO 42, 44, 45 and 52) were collected for this study. The concentrations of PAHs in the study rice samples were lower than the maximum allowable concentration (MAC), average daily dose (ADD) of PAHs in the different variety of rice from the six agricultural locations shows that FARO 44 had the highest ADD (5.84 x1011 mg/kg), while FARO 52 shows the lowest ADD (1.20 x1015 mg/kg). The potential for non-carcinogenic PAHs in this study revealed that FARO 42 has the highest hazard index (2.04 x1011 mg/kg). Result from incremental lifetime expectancy cancer risk shows that FARO 44 from Jawa had the highest value (4.19 x1010 mg/kg), while the lowest value (7.61 x1015 mg/kg) was recorded for FARO 52 from Rina Kuna agricultural location. Results from the present study shows that the rice samples from the study locations are safe for human consumption and not significantly contaminated by PAHs.

Occurrence, sources and health risk of polycyclic aromatic hydrocarbons in soils around oil wells in the border regions between oil fields and suburbs

The Yellow River Delta (YRD) is a typical region where oil fields generally overlap cities and towns, leading to complex soil contamination from both the oil fields and human activities. To clarify the distribution, speciation, potential sources and health risk of polycyclic aromatic hydrocarbons (PAHs) in soils of border regions between oil fields and suburbs of the YRD, 138 soil samples (0–20 cm) were collected among 12 sampling sites located around oil wells with different extraction histories. The 16 priority control PAHs (16PAHs), as selected by the United States Environmental Protection Agency (USEPA), were extracted via an accelerated solvent extraction and detected by GC-MS. The results showed that soils of the study area were generally polluted by the 16PAHs. Among these pollutions, chrysene and phenanthrene were the dominant components, and 4-ring PAHs were the most abundant. A typical temporal distribution pattern of the 16PAHs was revealed in soils from different sampling sites around oil wells with different exploitation histories. The concentrations of total 16PAHs and high-ring PAHs (HPAHs) both increased with the extraction time of the nearby oil wells. Individual PAH ratios and PCA method revealed that the 16PAHs in soil with newly developed oil wells were mainly from petroleum pollutants, whereas PAHs in soils around oil wells with a long exploitation history were probably from petroleum contamination; combustion of petroleum, fuel, and biomass; and degradation and migration of PAHs from petroleum. Monte Carlo simulation was used to evaluate the health risks of the 7 carcinogenic PAHs and 9 non-carcinogenic PAHs in the study area. The results indicated that ingestion and dermal contact were the predominant pathways of exposure to PAH residues in soils. Both the carcinogenic and non-carcinogenic burden of the 16PAHs in soils of the oil field increased significantly with exploitation time of nearby oil wells.

Exposure risks to polycyclic aromatic hydrocarbons by humans and livestock (cattle) due to hydrocarbon spill from petroleum products in Niger-delta wetland

In this study, the human and livestock (cattle) health risks of exposure to polycyclic aromatic hydrocarbons (PAHs) in a wetland of Obuaku, Abia State Nigeria contaminated by hydrocarbon spill due to incidents of hydrocarbon theft and pipeline vandalization were assessed. Gas chromatography-flame ionization detector and gas chromatography–mass spectrometry were employed in analyzing the TPH and PAHs respectively. The contaminated soil was delineated into sub-locations AOC-1, AOC-2, AOC-3, AOC-4, AOC-5 and AOC-6 to reflect the discrete patches (areas) of the contaminated site and for effective planning of remedial actions. The concentration of the PAHs in AOC-4 was insignificant but was quite significant in AOC-1, AOC-2, AOC-3 and AOC-6. The average percentage distribution of the PAHs in all the sites is 9.8% carcinogenic and 91.2% non-carcinogenic. The ecological risk assessment revealed that only sub-location AOC-4 contains PAH to a level of insignificant biological impairment while sub-locations AOC-1, AOC-2 and AOC-6 contain PAHs that pose the highest ecological risks. The assessment of health risk exposure to carcinogenic and non-carcinogenic PAHs indicated insignificant risks for all sub-locations whereas the assessment of health risks using PAH toxicity method indicates that only sub-locations AOC-1, AOC-2 and AOC-6 were toxic. These sub-locations were also found to be of significant health risks to livestock (cattle). Robust empirical models describing the relationships between TPH and any of the risk parameters were generated such that TPH can be used in predicting the risk parameters for spillage peculiar to petroleum products.

Gene-expression profiling of buccal epithelium among non-smoking women exposed to household air pollution from smoky coal.

In China's rural counties of Xuanwei and Fuyuan, lung cancer rates are among the highest in the world. While the elevated disease risk in this population has been linked to the usage of smoky (bituminous) coal as compared to smokeless (anthracite) coal, the underlying molecular changes associated with this exposure remains unclear. To understand the physiologic effects of smoky coal exposure, we analyzed the genome-wide gene-expression profiles in buccal epithelial cells collected from healthy, non-smoking female residents of Xuanwei and Fuyuan who burn smoky (n = 26) and smokeless (n = 9) coal. Gene-expression was profiled via microarrays, and changes associated with coal type were correlated to household levels of fine particulate matter (PM2.5) and polycyclic aromatic hydrocarbons (PAHs). Expression levels of 282 genes were altered with smoky versus smokeless coal exposure (P < 0.005), including the 2-fold increase of proinflammatory IL8 and decrease of proapoptotic CASP3. This signature was more correlated with carcinogenic PAHs (e.g. Benzo[a]pyrene; r = 0.41) than with non-carcinogenic PAHs (e.g. Fluorene; r = 0.08) or PM2.5 (r = 0.05). Genes altered with smoky coal exposure were concordantly enriched with tobacco exposure in previously profiled buccal biopsies of smokers and non-smokers (GSEA, q < 0.05). This is the first study to identify a signature of buccal epithelial gene-expression that is associated with smoky coal exposure, which in part is similar to the molecular response to tobacco smoke, thereby lending biologic plausibility to prior epidemiological studies that have linked this exposure to lung cancer risk.

Comparing the genotoxicity of a potentially carcinogenic and a noncarcinogenic PAH, singly, and in binary combination, on peripheral blood cells of the European sea bass.

Research on the toxicological mechanisms of polycyclic aromatic hydrocarbons (PAHs) deemed carcinogenic and noncarcinogenic has mostly been developed for individual compounds even though, in the environment, PAHs invariably occur in mixtures. The present work aimed at understanding the interaction effects of two model PAHs, the potentially carcinogenic benzo[b]fluoranthene (B[b]F) and the noncarcinogenic phenanthrene (Phe) to a marine fish (the sea bass Dicentrarchus labrax). The study endeavoured an ecologically-relevant scenario with respect to concentrations and contaminant matrix, sediments, which are the main reservoirs of these substances in the environment, due to their hydrophobic nature. For the purpose, 28-day laboratorial bioassays with spiked sediments (with individual and combined PAHs at equitoxic concentrations) were conducted. Genotoxicity was determined in peripheral blood through the "Comet" assay and by scoring erythrocytic nuclear abnormalities (ENA). The results showed that exposure to either PAHs induced similar levels of DNA strand breaks, although without a clear dose- or time-response, likely due to the low concentrations of exposure and potential shits in PAH bioavailability during the assays. However, clastogenic/aneugenic lesions were only observed in fish exposed to B[b]F-spiked sediments. Conversely, the combination assays revealed a supra-additive effect especially at chromosome level, linked to concentrations of PAHs in water. A decrease in DNA-strand breakage was observed over time during all assays, revealing some ability of fish to cope with this DNA lesion. Overall, the findings show that low-moderate concentrations of sediment-bound mixed PAHs may significantly increase the hazard of mutagenesis even when the individual concentrations indicate low risk, especially considering that chromosome-level damage is unlikely to be repaired, leading to the fixation of DNA lesions upon prolonged exposures. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 1307-1318, 2016.

Effects of carcinogenic versus non-carcinogenic AHR-active PAHs and their mixtures: Lessons from ecological relevance

Polycyclic aromatic hydrocarbons (PAHs) are priority environmental mutagens and carcinogens that occur in the aquatic environment as mixtures rather than the individual compounds for which guidelines are issued. The present work aimed at understanding the interaction effects between carcinogenic and non-carcinogenic PAHs in a model marine fish (Dicentrarchus labrax) in realistic scenarios. Laboratory assays under ecologically-relevant parameters were conducted for 28 days with sediments spiked with low-moderate concentrations (250–800ngg−1) of two model PAHs, phenanthrene (non-carcinogenic) and benzo[b]fluoranthene (carcinogenic to experimental animals). Both PAHs induced hepatic histopathological changes that indicate metabolic failure and inflammation, especially in animals exposed to mixtures. Phenanthrene elicited biochemical changes better related to oxidative stress (lipid peroxidation, glutathione and glutathione S-transferase activity) and CYP function, whereas B[b]F disrupted metabolic responses and defences to toxicological challenge. Conversely, mixed PAHs yielded lesions and responses that, altogether, are compatible with the AHR dependent pathway (the basis of PAH mutagenicity), potentially generating supra-additive effects. Nonetheless, the low, ecologically-relevant, concentrations of PAHs diluted dose and time-response relations. Overall, although seemingly predicting the risk of individual PAHs, environmental guidelines may not apply to mixtures by underestimating adverse effects, which calls for a redefinition of standards when determining the true risk of toxicants under realistic circumstances.

Analysis of the interaction of polycyclic aromatic compounds in a model organism: integration of genotoxic and histopathological effects

Event Abstract Back to Event Analysis of the interaction of polycyclic aromatic compounds in a model organism: integration of genotoxic and histopathological effects Sofia Pereira1*, Marta G. Martins1, Maria H. Costa1 and Pedro M. Costa1 1 IMAR - Instituto do Mar, Departamento de Ciências e Engenharia do Ambiente, Portugal Due to their toxicity, especially their carcinogenic potential, polycyclic aromatic hydrocarbons (PAHs) are considered priority in biomonitoring programmes. Many of these compounds are listed through the European Water Framework Directive as priority pollutants. Benzo(b)fluoranthene (B[b]F), considered potentially carcinogenic, and phenanthrene (Phe), non-carcinogenic, are two common PAHs in coastal waters and own distinct proprieties that are reflected in their mechanisms of toxicity. Still, their interaction effects onto the aquatic biota remain largely unknown. This work aimed to analyze the genotoxic effects caused by the interaction of B[b]F and Phe and their relation to histopathological alterations in the liver. The model organism was the seabass Dicentrarchus labrax, an important coastal species for fisheries and aquaculture. For the purpose, fish were injected with the two compounds (5 µg/g fish ww), isolated or in mixture, and incubated for 24h. The results only revealed minor clastogenic and aneugenic alterations, determined through erythrocytic nuclear abnormalities. On the other hand, the Comet assay showed significant DNA strand breakage in the individuals injected with B[b]F and the combination of the two compounds. On the contrary, Phe failed to cause significant genotoxic effects. Significant hepatic histopathological alterations were also found in animals injected with B[b]F, relating especially to inflammation-related responses. Overall, the results indicate no significant additive effect between B[b]F and Phe, under the current experimental conditions. Nonetheless, the seabass revealed to be sensitive to exposure to B[b]F (a higher molecular weight PAH), likely due to more efficient bioactivation of the pollutant (yielded genotoxic metabolites and reactive oxygen species), when compared to Phe. It is of paramount importance to understand the long-term interaction effects between PAHs under ecologically-relevant scenarios, since PAHs, like many other toxicants, are usually present in the aquatic environment as a complex mixture of xenobiotics. Acknowledgements Marta Martins was supported by the “Fundação para a Ciência e Tecnologia” (FCT) Ph.D grant ref. SFRH/BD/64510/2009. P.M. Costa was supported by the FCT post-doctoral grant ref. SFRH/BPD/72564/2010. Keywords: Benzo[b]fluoranthene, Phenanthrene, Carcinogenic PAH, Non-carcinogenic PAH, Histology, DNA strand breakage Conference: IMMR | International Meeting on Marine Research 2014, Peniche, Portugal, 10 Jul - 11 Jul, 2014. Presentation Type: Poster Presentation Topic: BIODIVERSITY, CONSERVATION AND COASTAL MANAGEMENT Citation: Pereira S, Martins MG, Costa MH and Costa PM (2014). Analysis of the interaction of polycyclic aromatic compounds in a model organism: integration of genotoxic and histopathological effects. Front. Mar. Sci. Conference Abstract: IMMR | International Meeting on Marine Research 2014. doi: 10.3389/conf.fmars.2014.02.00034 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 16 May 2014; Published Online: 18 Jul 2014. * Correspondence: Miss. Sofia Pereira, IMAR - Instituto do Mar, Departamento de Ciências e Engenharia do Ambiente, Caparica, 2829-016, Portugal, sa.pereira@campus.fct.unl.pt Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Sofia Pereira Marta G Martins Maria H Costa Pedro M Costa Google Sofia Pereira Marta G Martins Maria H Costa Pedro M Costa Google Scholar Sofia Pereira Marta G Martins Maria H Costa Pedro M Costa PubMed Sofia Pereira Marta G Martins Maria H Costa Pedro M Costa Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

Polycyclic aromatic hydrocarbons in food – Efflux of the conjugated biomarker 1-hydroxypyrene is mediated by Breast Cancer Resistance Protein (ABCG2) in human intestinal Caco-2 cells

Polycyclic aromatic hydrocarbons (PAHs) are well-known food contaminants comprising compounds with carcinogenic properties. Pyrene (PYR) is an important non-carcinogenic PAH because its metabolites are frequently used as biomarkers to assess human PAH exposure. This study investigated for the first time the formation and transport of PYR metabolites in the human small intestinal Caco-2 cell model using HPLC technique. The intermediate phase I metabolite 1-hydroxypyrene formed by cytochrome P450 monooxygenases is subsequently conjugated by phase II enzymes to the water-soluble PYR 1-glucuronide as minor and PYR 1-sulfate as major metabolites. The formation of the latter is mediated by human sulfotransferases 1A1∗Arg, 1A2∗1, 1A3, and 1B1. Caco-2 monolayer experiments revealed a predominantly apical transport of both conjugates mediated by the breast cancer resistance protein (BCRP/ABCG2). Additional treatment with several aryl hydrocarbon receptor (AhR) agonists indicate an AhR-driven induction of PYR-metabolizing enzymes and/or ABCG2. Overall, this study provides advanced mechanistic insights into the bioavailability of PYR and underlines a key role of the human small intestinal epithelium for the first pass metabolism of contaminants in food.

Comparative DNA damage and oxidative effects of carcinogenic and non-carcinogenic sediment-bound PAHs in the gills of a bivalve

Polycyclic aromatic hydrocarbons (PAHs) regarded as carcinogenic and non-carcinogenic to humans are ubiquitous hydrophobic pollutants that tend to be trapped in aquatic sediments. As a consequence of their acknowledged toxicity and pro-mutagenic or even carcinogenic potential, PAHs are deemed prioritary in biomonitoring programmes. Still, the differences between the toxicity of carcinogenic and non-carcinogenic PAHs are poorly known especially, when aquatic organisms are exposed to ecologically-relevant concentrations of these compounds in sediments. Laboratory bioassays with sediments spiked with phenanthrene (Phe) and benzo[b]fluoranthene (B[b]F), non-carcinogenic and carcinogenic PAH, respectively, were conducted and the effects of exposure (related to DNA damage and oxidative stress) were analyzed in the gills of a burrowing clam, Ruditapes decussatus (Bivalvia, Veneridae). To ensure ecological relevance, two contaminant concentrations (termed “low” and “high”) were selected in accordance with available PAH sediment quality guidelines. The results showed that, even in “low” concentrations, both compounds caused a likely genotoxic effect in the gills, which is in accordance with the link between PAHs in water. Glutathione S-transferase activity and glutathione biosynthesis appear to be associated with limited lipid peroxidation even though they were insufficient to prevent higher and faster genotoxicity induced by exposure to the carcinogenic B[b]F, comparative to Phe. Overall the findings indicate that low concentrations of sediment-bound PAHs, carcinogenic or not, may be rendered significantly bioavailable to benthic filter-feeders as to induce genotoxicity, revealing that even PAHs considered non-carcinogenic to humans detain a latent, albeit significant, pro-mutagenic hazard to bivalve molluscs.

Eco-toxicological and epidemiological assessment of human exposure to polycyclic aromatic hydrocarbons in the Niger Delta, Nigeria

Epidemiological examinations of polycyclic aromatic hydrocarbons (PAHs) exposure in biological bodies have shown the potential risk of cancer induction. Environmental media containing PAHs were analyzed in the Niger Delta region. Gas chromatographicmass spectrometric analyses were carried out on samples and 98% of the samples contained carcinogenic PAHs. The concentration of the 7 potential carcinogenic PAHs (Σ carc soil 7PAHs) in the soils varied from 297–4080.6±546.3 mg/kg (min-max +/- standard deviation) with a median of 419 mg/kg, the concentrations for non-carcinogenic PAHs ranged from 315–1999±300 mg/kg with a median of 497.5 mg/kg. The total concentrations of PAHs (»total H2O17PAHs) in water samples varied from 119.8–450.0±117.9 mg/L with a median of 141.9 mg/L, while the sediment concentrations ranged from 6.0–132.0±28.7 mg/L with a median of 62.73 mg/L. Concentrations of benzo(a) pyrene (BaP), which most likely originated from crude oil spillage in the area was determined as 66.95±73.47 mg/kg in soil samples. To evaluate human exposure to carcinogenic PAHs sources, the toxic equivalence factors (TEFs), mutagenic potency equivalent factors (MEFs) and the incremental lifetime cancer risk (ILCR) methodologies were used to calculate the exposure risk. Carcinogenic equivalents (BaP-TEQ) and mutagenic equivalents (BaP-MEQ) were calculated from the potency relative to BaP (TEF) and BAP (MEF) respectively. BaP-TEQ (mg/kg) for Ω carc soil 7PAHs were determined as 98.80±125.81 and varied from 68.20–953.84 mg/kg, while the BaPMEQ (mg/kg) for Σ carc soil 7PAHs were determined as 124.01±163.37 and varied from 87.24–1237.82 mg/ kg. The BaP-TEQ (mg/kg) for Ω carc H2O 7PAHs were determined as 16.79±14.44 and varied from 5.55–52.69 mg/L, similarly the BaP-MEQ (mg/kg) for Ω carc H2O 7PAHs were determined as 9.29±8.15 and varied from 1.55–29.80 mg/kg. The cumulative ILCR from the water and soil contaminations were determined as 1.13×10−4 and 6.42×10−4 respectively for children, while values of 1.09×10−4 and 6.19×10−4 were determined respectively for adult. The ecotoxicological assessments in this study indicate contamination of environmental media in the region with high potential of acute toxicity sufficient enough to induce carcinogenic effects and chronically affect the human health of residents with prolonged exposures.

Effect of Native American Fish Smoking Methods on Dietary Exposure to Polycyclic Aromatic Hydrocarbons and Possible Risks to Human Health

Although it is known that polycyclic aromatic hydrocarbons (PAHs) can be found in smoked meats, little is known about their prevalence in Native American smoked fish. In this work, the effect of traditional Native American fish smoking methods on dietary exposure to PAHs and possible risks to human health has been assessed. Smoking methods considered smoking structure (tipi or shed) and wood type (apple or alder). Neither smoking structure nor wood type accounted for differences in smoked salmon content of 33 PAHs. Carcinogenic and noncarcinogenic PAH loads in traditionally smoked salmon were 40-430 times higher than those measured in commercial products. Dietary exposure to PAHs could result in excess lifetime cancer risks between 1 × 10(-5) and 1 × 10(-4) at a daily consumption rate of 5 g d(-1) and could approach 1 × 10(-2) at 300 g d(-1). Hazard indexes approached 0.005 at 5 g d(-1), or approximately 0.3 at 300 g d(-1). Levels of PAHs present in smoked salmon prepared using traditional Native American methods may pose elevated cancer risks if consumed at high consumption rates over many years.

Internal exposure to carcinogenic polycyclic aromatic hydrocarbons and DNA damage: a null result in brief

We previously reported DNA strand break frequencies and adduct levels of 8-oxo-7,8-dihydro-20-deoxyguanosine (8-oxo-dGuo) in 171 blood samples of coke oven, refractory, graphite electrode, and converter workers exposed to polycyclic aromatic hydrocarbons (PAH). Construction workers (n = 48) were used as controls (Marczynski et al. 2009). Internal dose was assessed by the determination of 1-hydroxypyrene (1-OHP) and the sum of five hydroxyphenanthrenes ( P OHPhe) in post-shift urine samples. Our results clearly indicated increased DNA damage in exposed workers on a group level. The results of the dose–response associations on the individual level, however, did not reveal quantitative correlations between measured exposures and effects. We have discussed several potential reasons for the observed results. In brief, internal exposure and effect was based on single time points (post-shift samples), and kinetics for the formation of 8-oxo-dGuo and DNA strand breaks after exposure to chemical carcinogens such as PAH are not known in detail in humans. The individual exposure circumstances such as varying routes of exposures (dermal vs. inhalation) and potential co-exposures to dust or other chemical compounds at the workplace may have contributed to the dose–response association rather than exposure to PAH alone (Courter et al. 2007). Although PAH can undergo redox cycling and are capable of inducing oxidative DNA damage (Park et al. 2008), DNA strand breaks and 8-oxo-dGuo in blood are general biomarkers of oxidative stress, thus being pathwayspecific rather than substance-specific. Finally, PAH are a complex mixture consisting of carcinogenic and non-carcinogenic compounds and exist in varying profiles in different industries and the environment (Rehwagen et al. 2005; Unwin et al. 2006). 1-OHP and P OHPhe are metabolites of pyrene and phenanthrene, thus representing noncarcinogenic PAH rather than carcinogenic PAH. In order to narrow down the reasons for the lacking association between exposures to PAH and DNA damage on the individual level, we re-analyzed the role of carcinogenic PAH. For this purpose, we focused on benzo[a]pyrene (B[a]P) and naphthalene. B[a]P is a complete carcinogen and often used as a positive control in bioassays when studying genotoxicity and carcinogenicity of chemical compounds (IARC 2010). In addition, B[a]P has been shown to have the highest enzyme inducing efficiency in the lung and liver of rodents, thus self-enhancing the formation of reactive electrophilic and carcinogenic intermediates during its metabolism (Elovaara et al. 2007; Skupinska et al. 2007). Naphthalene has been shown to be carcinogenic in rodents at high concentrations after inhalation (NTP 2000). Available biomarkers to assess H. U. Kafferlein (&) B. Marczynski J. Angerer H.-P. Rihs B. Pesch T. Bruning Institut fur Pravention und Arbeitsmedizin der Deutschen Gesetzlichen Unfallversicherung, Institut der Ruhr Universitat Bochum (IPA), Burkle-de-la-Camp Platz 1, 44789 Bochum, Germany e-mail: kaefferlein@ipa-dguv.de

Phenanthrene metabolism in smokers: use of a two-step diagnostic plot approach to identify subjects with extensive metabolic activation.

Polycyclic aromatic hydrocarbons (PAHs) in cigarette smoke are among the most likely causes of lung cancer. PAHs require metabolic activation to initiate the carcinogenic process. Phenanthrene (Phe), a noncarcinogenic PAH, was used as a surrogate of benzo[α]pyrene and related PAHs to study the metabolic activation of PAHs in smokers. A dose of 10 μg of deuterated Phe ([D₁₀]Phe) was administered to 25 healthy smokers in a crossover design, either as an oral solution or by smoking cigarettes containing [D₁₀]Phe. Phe was deuterated to avoid interference from environmental Phe. Intensive blood and urine sampling was performed to quantitate the formation of deuterated r-1,t-2,3,c-4-tetrahydroxy-1,2,3,4-tetrahydrophenanthrene ([D₁₀]PheT), a biomarker of the diol epoxide metabolic activation pathway. In both the oral and smoking arms approximately 6% of the dose was metabolically converted to diol epoxides, with a large intersubject variability in the formation of [D₁₀]PheT observed. Two diagnostic plots were developed to identify subjects with large systemic exposure and significant lung contribution to metabolic activation. The combination of the two plots led to the identification of subjects with substantial local exposure. These subjects produced, in one single pass of [D₁₀]Phe through the lung, a [D₁₀]PheT exposure equivalent to the systemic exposure of a typical subject and may be an indicator of lung cancer susceptibility. Polymorphisms in PAH-metabolizing genes of the 25 subjects were also investigated. The integration of phenotyping and genotyping results indicated that GSTM1-null subjects produced approximately 2-fold more [D₁₀]PheT than did GSTM1-positive subjects.

Distribution behavior and carcinogenic level of some polycyclic aromatic hydrocarbons in roadside soil at major traffic intercepts within a developing city of India

A study of polycyclic aromatic hydrocarbons (PAHs) pollution in roadside soil was conducted at a developing city locations of Jalandhar (Punjab), India in winter season to ascertain the contamination levels and their distribution behavior in roadside soil. PAHs concentration level of ten locations was measured at 1, 2, and 3 m distances from roadside soil covering all the major traffic intercepts within a city. Samples were extracted in acetone and dichloromethane (1:1) using soxhlet extraction. The extracts were filtered on a silica gel micro column to remove impurities and eluate was subjected to GC-FID. The total average PAHs concentration (city average) was found to be 4.04 μg g(-1), whereas the concentration of 16 individual PAHs was found to vary between 0.008 and 28.4 μg g(-1). The average concentration of noncarcinogenic and carcinogenic PAHs in all the samples was 2.17 and 6.41 μg g(-1) (ratio 1:2.95). The concentration of five ringed PAHs was found to be 45% to 60%, whereas two ringed PAHs were found to be in the range from 0.28% to 0.56% in all most all locations. The average highest PAHs concentration for any individual location was found as 12.23 μg g(-1) at DAV Chowk at 1 m distance and minimum concentration was 0.98 μg g(-1) at Maqsuda Chowk at 1 m distance from roadside. DiB (ah) A was the individual PAHs found in highest concentration in all the intercepts ranging between 1.26 and 28 μg g(-1). At most of the city intercepts, total carcinogenic PAHs concentration was found to range from 60% to 80% in comparison to noncarcinogenic PAHs (20%-40%) at most of the intercepts. The pollution level our study was compared with other cities of India/worldwide.

Concentrations and dietary exposure to polycyclic aromatic hydrocarbons (PAHs) from grilled and smoked foods

We investigated the concentrations and profiles of 16 priority polycyclic aromatic hydrocarbons (PAHs) in various grilled and smoked foods and estimated the dietary exposure of Kuwaiti children, adolescent and adult populations. Results indicated that non-carcinogenic PAHs were present at high proportions (60–100%) with phenanthrene showing the highest mean concentration (54.9 μg kg−1, 37.1% of the total PAH concentrations). Among the genotoxic PAHs (PAH8), chrysene (4.88 μg kg−1, 3.29%) and benz[a]anthracene (2.27 μg kg−1, 1.53%) showed the highest mean values. Meat tikka contained the highest mean concentrations of benzo[a]pyrene (BaP) (2.48 μg kg−1), total genotoxic PAHs (42.9 μg kg−1), total PAHs (ΣPAHs) (648 μg kg−1) and total benzo[a]pyrene equivalents (ΣBaPeq) (6.02 μg kg−1). High levels of genotoxic PAHs were detected in grilled vegetables (21.1 μg kg−1), shish tauk (20.5 μg kg−1) and whole grilled chicken (20.3 μg kg−1) samples. However, meat and chicken shawerma samples had low levels of PAH8. Meat tikka (437 ng/day, 641 ng/day), whole grilled chicken (160 ng/day, 241 ng/day), grilled vegetables (120 ng/day, 166 ng/day), meat burger (114 ng/day, 92.7 ng/day) were the major contributors to the daily intake of PAH8 in children/adolescent and adult populations, respectively. The total mean dietary intakes for children/adolescents and adults for BaP (8.09 ng/day, 9.20 ng/day), PAH8 (84.2 ng/day, 95.7 ng/day), ∑PAHs (974 ng/day, 1108 ng/day) and ∑BaPeq (14.8 ng/day, 16.8 ng/day) were comparable. Cancer risks for Kuwaiti children/adolescents and adults from dietary intake of ΣBaPeq from the animal-origin foods were determined to be 2.63/107 and 9.3/107, respectively.

Highly sensitive routine method for urinary 3-hydroxybenzo[a]pyrene quantitation using liquid chromatography-fluorescence detection and automated off-line solid phase extraction

Many workers and also the general population are exposed to polycyclic aromatic hydrocarbons (PAHs), and benzo[a]pyrene (BaP) was recently classified as carcinogenic for humans (group 1) by the International Agency for Research on Cancer. Biomonitoring of PAHs exposure is usually performed by urinary 1-hydroxypyrene (1-OHP) analysis. 1-OHP is a metabolite of pyrene, a non-carcinogenic PAH. In this work, we developed a very simple but highly sensitive analytical method of quantifying one urinary metabolite of BaP, 3-hydroxybenzo[a]pyrene (3-OHBaP), to evaluate carcinogenic PAHs exposure. After hydrolysis of 10 mL urine for two hours and concentration by automated off-line solid phase extraction, the sample was injected in a column-switching high-performance liquid chromatography fluorescence detection system. The limit of quantification was 0.2 pmol L(-1) (0.05 ng L(-1)) and the limit of detection was estimated at 0.07 pmol L(-1) (0.02 ng L(-1)). Linearity was established for 3-OHBaP concentrations ranging from 0.4 to 74.5 pmol L(-1) (0.1 to 20 ng L(-1)). Relative within-day standard deviation was less than 3% and relative between-day standard deviation was less than 4%. In non-occupationally exposed subjects, median concentrations for smokers compared with non-smokers were 3.5 times higher for 1-OHP (p<0.001) and 2 times higher for 3-OHBaP (p<0.05). The two urinary biomarkers were correlated in smokers (ρ=0.636; p<0.05; n=10) but not in non-smokers (ρ=0.09; p>0.05; n=21).

Distribution behavior of polycyclic aromatic hydrocarbons in roadside soil at traffic intercepts within developing cities

A study of polycyclic aromatic hydrocarbons pollution in roadside soil was conducted in developing city environment of northern India during autumn and winter season to ascertain the contamination levels and their distribution behavior in soil. The concentration of polycyclic aromatic hydrocarbons was determined at ten locations of Jalandhar city, Punjab in India at 1, 2 and 3 m distances from roadside in soil covering all the major traffic intercepts within city. The samples were extracted in acetone and dichloromethane (1:1) using soxhlet extraction. The extracts were then filtered on a silica gel micro column to remove impurities and elute was subjected to GC-FID. The total average concentration (city average) was found to be 4.04 ⧎g/g and 16.38 ⧎g/g during winter and autumn respectively. DiBenzo (ah) Anthracene and Benzo (a) Pyrene were the individual polycyclic aromatic hydrocarbons found in highest concentration at all the intercepts ranging between 0.008 to 28.4 ⧎g/g during winter and 0.01 to 252.55 ⧎g/g during autumn. Average concentration of non-carcinogenic and carcinogenic polycyclic aromatic hydrocarbons during winter and autumn was found to be 2.1 and 6.4 and 4.74 and 35.08 ⧎g/g respectively. The average ratio of non-carcinogenic and carcinogenic Polycyclic Aromatic Hydrocarbons was found to be 1:3 during winter, and 1:7.6 during autumn at most of the intercepts. Total carcinogenic polycyclic aromatic hydrocarbons concentration was found quite high (80 %) in comparison to non-carcinogenic polycyclic aromatic hydrocarbons (20 %) at most of the intercepts.

Benzo[a]pyrene and total polycyclic aromatic hydrocarbons (PAHs) levels in vegetable oils and fats do not reflect the occurrence of the eight genotoxic PAHs

Concentrations of polycyclic aromatic hydrocarbons (PAHs) were determined in 115 samples of olive oil (extra virgin olive oil, virgin olive oil, olive oil, pomace olive oil and blended olive oil), cooking oil (corn oil, sunflower oil, sesame oil, palm olein oil, soya oil, canola oil, mustard oil, peanut oil and mixed vegetable oil) and fat (butter and table margarine) collected from retail stores in Kuwait. Carcinogenic benzo[a]pyrene (BaP) was detected in 43% of the samples analyzed. Benz[a]anthracene and chrysene were detected in 37 and 45% of the samples, respectively, that did not contain BaP. Of the individual non-carcinogenic PAHs, naphthalene showed the highest mean concentration (14 µg kg−1), while for the carcinogenic PAHs, BaP (0.92 µg kg−1) and chrysene (0.87 µg kg−1) showed the highest mean values. Approximately 20% of the samples within the olive oil and cooking oil sub-categories exceeded the EU maximum tolerable limit for BaP, with the highest level of 6.77 and 11.1 µg kg−1, respectively. For the fat sub-category, 9% of the samples exceeded the tolerance limit, with the highest level of 3.67 µg kg−1. The Kuwaiti general population's dietary exposure to the genotoxic PAHs (PAH8: benz[a]anthracene, chrysene, benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[a]pyrene, indeno[1,2,3-cd]pyrene, dibenz[a,h]anthracene and benzo[ghi]perylene) was estimated to be 196 ng day−1 (3.3 ng kg−1 bw day−1, assuming an average adult body weight of 60 kg). Results indicated that PAH8 and BaPeq (total sum benzo[a]pyrene equivalents) are more reliable measures of the concentrations of other carcinogenic PAHs in oil and fat samples, while BaP and PAHs alone are not good indicators of the occurrence or degree of contamination by carcinogenic PAHs in these food products.