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Long-term exposure to vehicle exhaust gas may lead to various age-associated disorders, including cardiovascular disease and cancer. Polycyclic aromatic hydrocarbons (PAHs) belong to an important class of carcinogens, which are released into the environment by vehicles and are detectable at high levels in Chinese urban areas. However, whether vehicle exhaust gas (EG), and in particular the PAHs derived from EG, are able to induce cell senescence remains unclear. In the present study, vehicle EG and pure PAHs were used as pollution sources to investigate the effects of long-term exposure to PAH on the cellular processes occurring in mouse lung fibroblast cells (mLFCs). Using cell proliferation and apoptosis assays, it was demonstrated that benzopyrene (BaP) suppressed the proliferation of mLFCs, and benzanthracene (BaA) and BaP induced cell apoptosis. Molecular analysis suggested that long-term exposure to BaA and BaP was able to increase the protein expression levels of p53, p21 and the apoptotic factors involved in the caspase cascade, including caspase-3 and −9. Notably, the present study suggested that PAH exposure was able to promote cell senescence in mLFCs by activating the ATM serine/threonine kinase/H2A histone family member X pathway. The present study may provide novel insights into the underlying mechanism of vehicle EG and PAHs in promoting the development of age-associated diseases. [ABSTRACT FROM AUTHOR]

Asia, especially China, shares a large proportion of global aquaculture production. Consequently, aquaculture food quality and safety with regard to contamination with polycyclic aromatic hydrocarbons (PAHs) were assessed in eastern China, which is a typical area of aquaculture. The concentrations of ∑PAHs ranged from 42 to 600 ng/g dry weight in a variety of dietary species from farm ponds in eastern China. With regard to the total daily intake of PAHs estimated based on the literature data on urinary hydroxy‐PAHs in this region, there was a significant difference between children (mean = 130 ng/kg/d) and adults (mean = 600 ng/kg/d for pregnant women, 1700 ng/kg/d for women, and 2300 ng/kg/d for men). Furthermore, we provided a novel estimation on the fractional contribution of aquatic products to the overall human daily intake of PAHs. Specifically, the contribution of aquatic foodstuffs to total daily intake for children and pregnant women reached more than 50 and 10%, respectively, indicating that children and pregnant women were more vulnerable to the PAH‐contaminated aquaculture foodstuffs. Meanwhile, no significant region‐specific pattern between different provinces was observed. In summary, these results suggested that sensitive subpopulations were vulnerable to exposure to PAH‐contaminated aquatic products, and it is necessary to pay attention to the dietary intake pattern of these sensitive subgroups in eastern China. Environ Toxicol Chem 2019;00:1–9. © 2019 SETAC [ABSTRACT FROM AUTHOR]

To screen the tens of thousands of chemicals for which no toxicity data currently exists, it is necessary to move from in vivo rodent models to alternative models, such as zebrafish. Here, we used dechorionated Tropical 5D wild-type zebrafish embryos to screen a 91-compound library provided by the National Toxicology Program (NTP) for developmental toxicity. This library contained 86 unique chemicals that included negative controls, flame retardants, polycyclic aromatic hydrocarbons (PAHs), drugs, industrial chemicals, and pesticides. Fish were exposed to 5 concentrations of each chemical or an equal amount of vehicle (0.5% DMSO) in embryo medium from 6 h post-fertilization (hpf) to 5 days post-fertilization (dpf). Fish were examined daily for mortality and teratogenic effects and photomotor behavior was assessed at 4 and 5 dpf. Of the 5 negative control compounds in the library, none caused mortality/teratogenesis, but two altered behavior. Chemicals provided in duplicate produced similar outcomes. Overall, 13 compounds caused mortality/teratology but not behavioral abnormalities, 24 only affected behavior, and 18 altered both endpoints, with behavior affected at concentrations that did not cause mortality/teratology (55/86 hits). Of the compounds that affected behavior, 52% caused behavioral abnormalities at either 4 or 5 dpf. Compounds within the same functional group caused different behavioral abnormalities, while similar behavioral patterns were caused by compounds from different groups. Our data suggest that behavior is a sensitive endpoint for developmental toxicity screening that integrates multiple modes of toxic action and is influenced by the age of the larval fish at the time of testing. [ABSTRACT FROM AUTHOR]

Abstract Polycyclic aromatic hydrocarbons (PAHs) present in crude oil have been shown to cause the dysregulation of genes important in eye development and function, as well as morphological abnormalities of the eye. However, it is not currently understood how these changes in gene expression are manifested as deficits in visual function. Embryonic red drum (Sciaenops ocellatus) and sheepshead minnow (Cyprinodon variegatus) were exposed to water accommodated fractions (WAFs) of weathered crude oil and assessed for visual function using an optomotor response assay in early life-stage larvae, with subsequent samples taken for histological analysis of the eyes. Larvae of both species exposed to increasing concentrations of oil exhibited a reduced optomotor response. The mean diameters of retinal layers, which play an important role in visual function and image processing, were significantly reduced in oil-exposed sheepshead larvae, though not in red drum larvae. The present study provides evidence that weathered crude oil has a significant effect on visual function in early life-stage fishes. Graphical abstract fx1 Highlights • Visual function reduced in oil-exposed larvae. • Reduction in visually-mediated optomotor response assay in oil-exposed larvae. • Histological differences in exposed sheepshead, though not red drum. [ABSTRACT FROM AUTHOR]

Abstract In this study, source-specific cancer risk characterization of ambient PM 2.5 -bound polycyclic aromatic hydrocarbons (PAHs) was performed in central Tehran. The positive matrix factorization (PMF) model was applied for source apportionment of PAHs in the area from May 2012 through May 2013. The PMF runs were carried out using chemically analyzed PAHs mass concentrations. Five factors were identified as the major sources of airborne PAHs in central Tehran, including petrogenic sources and petroleum residue, natural gas and biomass burning, industrial emissions, diesel exhaust emissions, and gasoline exhaust emissions, with approximately similar contributions of around 20% to total PAHs concentration from each factor. Results of the PMF source apportionment (i.e., PAHs factor profiles and contributions) were then used to calculate the source-specific lung cancer risks for outdoor and lifetime exposure, using the benzo[α]pyrene (BaP) equivalent method. Our risk assessment analysis indicated that the lung cancer risk associated with each specific source is within the range of 10−6–10−5, posing cancer risks exceeding the United States Environmental Protection Agency's (USEPA) guideline safety values (10−6). Furthermore, the epidemiological lung cancer risk for lifetime exposure to total ambient PAHs was found to be (2.8 ± 0.78) × 10−5. Diesel exhaust and industrial emissions were the two sources with major contributions to the overall cancer risk, contributing respectively to 39% and 27% of the total risk associated with exposure to ambient PAHs. Results from this study provide an estimate of the cancer risk caused by exposure to ambient PAHs in highly crowded areas in central Tehran, and can be used as a guide for the adoption of effective air quality policies in order to reduce the human exposure to these harmful organic species. Highlights • PMF resolved 5 sources with almost equal contributions to PAHs concentrations. • Sources were gasoline, diesel, gas combustion, petrogenic, and industrial emissions. • The lifetime lung cancer risk of exposure to outdoor-originated PAHs was 2.8×10-5. • Diesel and industrial emissions were dominant (70%) contributors to cancer risk. • Results indicate significant cancer risks of exposure to PAHs in central Tehran. [ABSTRACT FROM AUTHOR]

The toxicity of polycyclic aromatic hydrocarbons (PAHs) mixtures was evaluated on natural phytoplankton communities sampled from lagoons of Bizerte (South-western Mediterranean Sea) and Thau (North-western Mediterranean Sea). PAHs induced short-term dose and ecosystem-dependant decreases in photosynthetic potential. Chlorophyll a was negatively affected by increasing PAHs concentrations, together with dramatic changes in phytoplankton community composition. Size classes were strongly affected in the Bizerte compare to the Thau lagoon, with a decrease in nano- and microphytoplankton densities compare to picophytoplankton. In both locations, the diatom Entomoneis paludosa appeared favoured under PAH exposure as evidenced by increase in cell density, whereas autotrophic flagellates and dinophytes were strongly reduced. Smaller cells were more tolerant to exposure to highest PAHs concentrations, with persistent picophytoplankton carbon biomass at the end of the incubations. Apparent recovery of photosynthetic potential, accompanied with a regrowth of chlorophyll a under the lowest PAH doses, coincided with a significantly altered community composition in both lagoons. Furthermore, sensitivity to PAHs was not related to the phytoplankton cell size, and toxicity-induced modification of top-down control by grazers during the experiment cannot be excluded. [ABSTRACT FROM AUTHOR]

In the ambient is >2000 chemical substances, some of them are absorbed on the surface of the particulate matter and may causes many health problems. Air pollution is responsible for >3.2 million premature deaths which classifies it as a second place environmental risk factor. Especially dangerous for health are polycyclic aromatic hydrocarbons and their derivatives which shows mutagenic and carcinogenic properties. Air pollutions were also classified by International Agency for Research on Cancer to group which carcinogenic properties on human were proved by available knowledge. Air pollutions, are one of the biggest problem in Polish cities. The article presents results of mutagenicity, genotoxicity and cytotoxicity researches conducted on a particulate matter fraction 2.5 μm collected during all year long in Wroclaw agglomeration (Poland). The material was collected on filters using high-flow air aspirator and extracted using dichloromethane. Additionally it was fractionated into 4 parts containing: all pollutants, only polycyclic aromatic hydrocarbons, nitro derivatives of PAHs and dinitro derivatives of PAHS. Dry residue of this fraction was dissolving in DMSO and tested using biological methods. Biological methods include mutagenicity properties which are investigated by Salmonella assay (Ames assay). Other biological method was comet assay and 4 parameter cytotoxicity test PAN-I assay. Results of the conducted experiments show differences in mutagenic, genotoxic and cytotoxic properties between seasons of collection and between volumes of dust pollutions fractions. The worst properties shows particles collected in autumn and winter season Results showed also some correlations in results obtained during different methods and properties. Due to the limited possibilities of testing all chemical compounds present in the PM2.5 fraction, it is recommended to carry out tests based on a set of genotoxic and cytotoxic tests, which is confirmed by the conducted research. [ABSTRACT FROM AUTHOR]

Abstract Polycyclic aromatic hydrocarbons (PAHs) are organic contaminants exhibiting carcinogenic toxicity. They are widespread in the environment, especially in urban areas. Humans are exposed to PAHs via inhalation, ingestion and dermal contact. Though much research has investigated their toxicity, little is known regarding the metabolic responses in humans after exposing to PAHs. However, those studies are important since PAHs become carcinogenic after metabolic activation by humans as indirect-acting carcinogens. As such, it is important to study their metabolism in humans based on metabolomics analysis. The goal of metabolomics study is to obtain a comprehensive view of metabolic reactions in humans after exposing to PAHs to better control the underlying metabolisms and reduce their genotoxicity. This article reviewed the biomarkers, analytical techniques including nuclear magnetic resonance and mass spectrometry, big data multivariate statistical analysis, and animal models that have been utilized to better understand the biological effects of PAHs, PAH-derivatives, and their metabolites and biotransformation products on humans. Graphical abstract Unlabelled Image Highlights • Reviewed metabolic activation and biotransformation of PAHs • Focused on metabolomics of PAH exposure and mechanisms of carcinogenesis • Covered associated biomarkers, analytical approaches and data analysis • Human and animal models were also discussed. [ABSTRACT FROM AUTHOR]

The International Agency for Research on Cancer recently classified straight-run bitumens and associated emissions during road paving as possibly carcinogenic to humans (Group 2B), owing to potential exposures to polycyclic aromatic hydrocarbons. We examine existing chemistry, exposure, epidemiology, and animal toxicity data to explore quantitative cancer risk implications for paving workers exposed to asphalt emissions from the data used in identifying this qualitative hazard. Epidemiology studies show no consistent cancer risk elevation. One skin-painting mouse study of paving asphalt emission condensate found a single tumor at only the highest tested dose, as did one rat inhalation study. These studies were used to develop an upper bound on possible carcinogenic potency of emissions that are inhaled or dermally deposited. Extending earlier work on roofing asphalt, we conducted time-to-tumor modeling using the dose-time-response shape for several dose levels of benzo[a]pyrene (B[a]P) in concurrent bioassay controls to infer presumed parallel dose-time-response curves for paving-asphalt-emission condensate. In addition, we developed a scientific rationale, based on general scaling considerations and on dermal uptake, for the chosen means to scale observed dermal cancer potencies in mice to apply to dermal exposures in humans. The results indicate that paving asphalt emissions have a reduced dermal cancer potency compared to roofing asphalt, consistent with the lower levels of the multi-ringed PAHs implicated in cancer risks. Based on existing occupational exposure studies, cancer risks to pavers from both dermal and inhalation exposure to asphalt emissions is within a range typically acceptable within regulatory frameworks. [ABSTRACT FROM AUTHOR]

In a market-basket study conducted in Cairo, Egypt, the most commonly consumed milk products were sampled and the contents of 13 polycyclic aromatic hydrocarbons were analyzed using gas chromatography with a mass spectrometer detector. The obtained data showed that the total amount of 13 PAHs was within the range of 1.3-8.2 μg/g. The results proved that the, highest mean levels of polycyclic aromatic hydrocarbons were detected in powdered milk (8.2 μg/g) followed by ultra-heat treatment milk and milk beverages (6.07 μg/g). The lowest level was detected in unsmoked cheese and yogurt (1.3 μg/g). Estimated daily intake (EDI) was used to estimate the carcinogenic risk. The total mean estimated daily intake for children in different age categories (1-10 years) was calculated with respect to benzo[a]pyrene, which ranged from 0.058 to 0.31 mg/day. The total mean value of EDI for the sum of seven carcinogenic PAHs in terms of benzo[a]pyrene ranged from 0.61 to 1.22 mg/day in all age categories. These results were higher than the critical limit set by the European Food Safety Authority. Therefore, there should be concerns regarding the effects of the consumption of different milk products on the local population. [ABSTRACT FROM AUTHOR]

In present study, we compared for the first time the cytotoxicities of the 16 priority polycyclic aromatic hydrocarbons (PAHs) in human pulmonary alveolar epithelial cells HPAEpiC. Moreover, we examined the effects of each PAH on oxidative stress (SOD, GSH, and ROS), cell viability, extracellular LDH, and apoptosis. The 16 priority PAHs were classified into four levels of cytotoxicity: (1) high cytotoxicity, BkF, BaP, and DBA; (2) moderate cytotoxicity, BbF, IND, BghiP, BaA, and CHR; (3) low cytotoxicity, PA, FL, and Pyr; and (4) mild cytotoxicity, Nap, AcPy, Acp, Flu, and Ant. Most of the PAHs showed benzene-ring-related cytotoxicity, except PA with 3-ring structure, cytotoxicity of which is similar to those of FL and Pyr with 4-ring structure. Results indicated the need for more studies on DBA, IND, and BghiP, among others, which are rarely investigated. PA, FL, and Pyr with little carcinogenicity should also be evaluated. This study will provide useful references for studies on the effects of PAHs on different cells or animal models. [ABSTRACT FROM AUTHOR]

This study was conducted for the purpose of extracting and estimating some PAHs of six vegetable oils selected They (ginger, cloves, bitter almonds, castor, mint and sesame) are used locally for medical, skin and skin treatments. Highperformance liquid chromatography (HPLC) technique is used to estimate these PAHs in the vegetable oil samples under study and the standard solution for calculating the retention time for each compound and to identify the area of each peak for vegetable oil samples and the standard solution. The results showed that the concentrations of vegetable oil samples, calculated according to the time of detention between the sample and the standard solution, showed only two compounds, acenaphthylene, Benzo (g, h, i) perylene, with bitter almond oil and sesame oil. While the rest of the compounds did not appear in all study samples, the concentrations are very low and this indicates that these vegetable oils are free from the risk of PAHs. Most of the PHAs compounds were not included in all study samples except acenaphthylene and Benzo (g, h, i) perylene compounds in almond oil and sesame oil but with very few concentrations are not dangers to human health. [ABSTRACT FROM AUTHOR]

Benzo[a]pyrene (BaP), a polycyclic aromatic hydrocarbon (PAH), is a known human carcinogen. In non-smoking adults greater than 95% of BaP exposure is through diet. The carcinogenicity of BaP is utilized by the U.S. EPA to assess relative potency of complex PAH mixtures. PAH relative potency factors (RPFs, BaP = 1) are determined from high dose animal data. We employed accelerator mass spectrometry (AMS) to determine pharmacokinetics of [ 14 C]-BaP in humans following dosing with 46 ng (an order of magnitude lower than human dietary daily exposure and million-fold lower than animal cancer models). To assess the impact of co-administration of food with a complex PAH mixture, humans were dosed with 46 ng of [ 14 C]-BaP with or without smoked salmon. Subjects were asked to avoid high BaP-containing diets and a 3-day dietary questionnaire given to assess dietary exposure prior to dosing and three days post-dosing with [ 14 C]-BaP. Co-administration of smoked salmon, containing a complex mixture of PAHs with an RPF of 460 ng BaP eq , reduced and delayed absorption. Administration of canned commercial salmon, containing very low amounts of PAHs, showed the impacts on pharmacokinetics were not due to high amounts of PAHs but rather a food matrix effect. [ABSTRACT FROM AUTHOR]

Many workers are occupationally exposed to polycyclic aromatic hydrocarbons (PAHs), which may cause various health problems, and some PAHs are known or suspected carcinogens. PAH exposure is primarily monitored by air sampling, but contamination may also occur through dermal exposure. PAHs adsorbed to the skin can be sampled by tape-stripping, but subsequent extraction of sampling tapes in organic solvent also releases diverse co-eluting substances that are difficult to remove before analysis of the PAHs by gas chromatography/mass spectrometry (GC/MS). The objective of this study was to optimise a procedure for analytical clean-up after extraction of 32 PAHs from tape-strips, by dialysis in organic solvent using semipermeable membranes. With triplicate subsamples, the developed method yields acceptable precision and repeatability for both the 32 PAHs, across the concentration range 10–160 ng per sample, and for a certified reference material (urban dust). The optimized clean-up procedure and GC/MS methodology was used to assess PAHs on skin from the lower part of the ventral side of the wrist and just below the collar bone of three firefighters and seven controls (office workers). Several gaseous and particle-bound PAHs were detected in all samples, including controls. Thus, the optimized procedure using semipermeable membranes for clean-up of tape-strip extracts can be used to assess the dermal exposure of both occupational and general populations to multiple PAHs. The results also show that both gaseous and particle-bound PAHs, including alkylated species, may be present on skin. [ABSTRACT FROM AUTHOR]

Road construction workers are simultaneously exposed to two carcinogens; solar ultraviolet (UV-S) radiation and polycyclic aromatic hydrocarbons (PAHs) in bitumen emissions. The combined exposure may lead to photogenotoxicity and enhanced PAH skin permeation rates. Skin permeation rates (J) for selected PAHs in a mixture (PAH-mix) or in bitumen fume condensate (BFC) with and without UV-S co-exposures were measured with in vitro flow-through diffusion cells mounted with human viable skin and results compared. Possible biomarkers were explored. J s were greater with UV-S for naphthalene, anthracene, and pyrene in BFC (0.08–0.1 ng/cm 2 /h) compared to without (0.02–0.26 ng/cm 2 /h). This was true for anthracene, pyrene, and chrysene in the PAH-mix. Naphthalene and benzo(a)pyrene (BaP) in the PAH-mix had greater Js without (0.97–13.01 ng/cm 2 /h) compared to with UV-S (0.40–6.35 ng/cm 2 /h). Time until permeation (T lags ) in the PAH-mix were generally shorter compared to the BFC, and they ranged from 1 to 13 h. The vehicle matrix could potentially be the reason for this discrepancy as BFC contains additional not identified substances. Qualitative interpretation of p53 suggested a dose-response with UV-S, and somewhat with the co-exposures. MMP1, p65 and cKIT were not exploitable. Although not statistically different, PAHs permeate human viable skin faster with simultaneous exposures to UV. [ABSTRACT FROM AUTHOR]

Regional-scale mass balance models are often used to simulate the multimedia environmental behaviors of organic contaminants. Variables with spatial and temporal characteristics in these models are important factors of their authenticity. The BETR-MFG(IV) model was developed to characterize the spatial and temporal variations as well as health risks of 16 priority polycyclic aromatic hydrocarbons (PAHs) in Daqing City, a typical petroleum industrial city in the Heilongjiang Province, China. The non-carcinogenic and carcinogenic health risks of these contaminants are assessed on the basis of the BETR-MFG(IV) modeled results. The simulated results showed that the temporal trends of the PAHs in the multimedia environments are in a relative steady state, and the most seriously contaminated area is the municipal districts of Daqing City. It was also demonstrated that the soil is the dominant sink and that the contaminants in the water and sediment are mainly concentrated in the Nanyin Reservoir and Daqing Reservoir. The health risks of the ΣPAHs in the study area primarily come from the pathways of soil ingestion and skin exposure. These findings are helpful to determine the spatio-temporal exposure characteristics of the contaminants, which will provide a scientific guideline for environmental protection and risk management. [ABSTRACT FROM AUTHOR]

Polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) are priority contaminants that bioaccumulate through the food webs and affect the biology of a variety of resident and migratory species, including sea turtles. Few studies have evaluated toxicological biomarkers of exposure to PAHs and PCBs in these animals. The present paper reports the results of an initial field study to quantify the association between plasma concentrations of PAHs/PCBs and whole blood cell expression of gene biomarkers in juvenile loggerhead sea turtles ( Caretta caretta ) rescued along the Italian coasts of the northern and central areas of the Adriatic Sea. While detectable levels of PAHs were found in all plasma samples examined, only three PCB congeners (PCB52, PCB95, and PCB149) were noted, with detection percentages ranging between 48% and 57%. A significant correlation was found between 3 of the 6 gene biomarkers assessed (HSP60, CYP1A and ERα) and plasma levels of some PAH congeners. In contrast, no significant association between PCB burden and gene expression was observed. The global DNA methylation levels were significantly and positively correlated with the concentrations of most of the PAHs and only one of the PCB congeners (PCB52). The relation between PAH concentration and gene expression in whole blood cells suggests that these genes may respond to environmental contaminant exposure and are promising candidates for the development of biomarkers for monitoring sea turtle exposure to persistent organic pollutants (POPs). [ABSTRACT FROM AUTHOR]

Semi-volatile organic compounds (SVOCs) present in indoor environments are known to cause adverse health effects through multiple routes of exposure. To assess the aggregate exposure, the bioaccessibility and bioavailability of SVOCs need to be determined. In this review, we discussed measurements of the bioaccessibility and bioavailability of SVOCs after inhalation. Published literature related to this issue is available for 2,3,7,8-tetrachlorodibenzo-p-dioxin and a few polycyclic aromatic hydrocarbons, such as benzo[ a ]pyrene and phenanthrene. Then, we reviewed common modeling approaches for the characterization of the gas- and particle-phase partitioning of SVOCs during inhalation. The models are based on mass transfer mechanisms as well as the structure of the respiratory system, using common computational techniques, such as computational fluid dynamics. However, the existing models are restricted to special conditions and cannot predict SVOC bioaccessibility and bioavailability in the whole respiratory system. The present review notes two main challenges for the estimation of SVOC bioaccessibility and bioavailability via inhalation in humans. First, in vitro and in vivo methods need to be developed and validated for a wide range of SVOCs. The in vitro methods should be validated with in vivo tests to evaluate human exposures to SVOCs in airborne particles. Second, modeling approaches for SVOCs need to consider the whole respiratory system. Alterations of the respiratory cycle period and human biological variability may be considered in future studies. [ABSTRACT FROM AUTHOR]

Exposure to the PM 10 /PM 2.5 -bound polycyclic aromatic hydrocarbons (PAHs) is a severe problem in heavily polluted cities in China. Designing effective air pollution management policies requires knowledge of the sources and health risks of PM 10 /PM 2.5 -bound PAHs. This study investigates the comparative differences of meteorological influences on PM 10 /PM 2.5 -bound PAHs distributions, as well as their potential sources and health risks. The aim of this study is to provide a science-based rationale for particle-bound PAHs pollution control. Both PM 10 and PM 2.5 samples were collected in the center of Beijing, China in winter and summer from 2013 to 2015. The meteorological conditions were monitored simultaneously. An analysis of the correlation between meteorological variables and PAHs concentrations indicates that average temperature, rainfall, and solar radiation had the most significant influences on the PAHs concentrations. A Principal component analysis combined with a diagnostic ratio tool is applied to the source apportionment of particle-bound PAHs, which indicates that diesel, gasoline, and coal combustion contribute most to PAHs pollution. The high emissions of the PM 10 /PM 2.5 -bound PAHs result in a 3.72 × 10 −3 /3.31 × 10 −3 and 5.79 × 10 −5 /4.39 × 10 −5 excess lung cancer risk in winter and summer, respectively. PM 2.5 contains more PAHs than the coarser fraction (PM 2.5-10 ), and accounts for 89% (winter) and 76% (summer) of the health risk caused by PM 10 . Given the higher risks caused by PM 2.5 than the PM 2.5-10 portion, PM 2.5 should be treated as the prioritized-control pollutant. Moreover, actively reducing the combustion of fossil fuels and a strategy of changing residents’ exposure characteristics are proposed for the mitigation of particle-bound PAHs pollution and control of health risks. [ABSTRACT FROM AUTHOR]

The levels, sources and quantitative probabilistic health risks for polycyclic aromatic hydrocarbons (PAHs) in agricultural soils in the vicinity of power, steel and petrochemical plants in the suburbs of Shanghai are discussed. The total concentration of 16 PAHs in the soils ranges from 223 to 8214 ng g − 1 . The sources of PAHs were analyzed by both isomeric ratios and a principal component analysis-multiple linear regression method. The results indicate that PAHs mainly originated from the incomplete combustion of coal and oil. The probabilistic risk assessments for both carcinogenic and non-carcinogenic risks posed by PAHs in soils with adult farmers as concerned receptors were quantitatively calculated by Monte Carlo simulation. The estimated total carcinogenic risks (TCR) for the agricultural soils has a 45% possibility of exceeding the acceptable threshold value (10 − 6 ), indicating potential adverse health effects. However, all non-carcinogenic risks are below the threshold value. Oral intake is the dominant exposure pathway, accounting for 77.7% of TCR, while inhalation intake is negligible. The three PAHs with the highest contribution for TCR are BaP (64.35%), DBA (17.56%) and InP (9.06%). Sensitivity analyses indicate that exposure frequency has the greatest impact on the total risk uncertainty, followed by the exposure dose through oral intake and exposure duration. These results indicate that it is essential to manage the health risks of PAH-contaminated agricultural soils in the vicinity of typical industries in megacities. [ABSTRACT FROM AUTHOR]

Exposure to polycyclic aromatic hydrocarbons (PAHs) could cause high blood pressure (BP) and increased risk for atherosclerotic cardiovascular disease (ASCVD). However, the mechanisms underlying the relationship between them were unclear. We investigated potential mediation effect of obesity on the association of exposure to PAHs with high BP and increased risk for ASCVD. In the repeated measures study, 106 community-dwelling residents in Wuhan, China finished the physical examination in the winter and summer seasons, eight urinary PAHs metabolites were measured. Associations of urinary PAHs with high BP and increased risk for ASCVD were assessed using either linear mixed effect models or generalized estimating equations models. Mediation analysis was performed to evaluate the mediating effect of obesity on the association of urinary PAHs metabolites with high BP or increased risk of ASCVD. We observed the positive association between urinary PAHs metabolites and BP or the odds ratios for high BP (all P < 0.05). Additionally, each one-unit increase in ln-transformed urinary levels of 4-hydroxyphenanthrene or the total of PAH metabolites was associated with a 12.63% or 11.91% increase in the estimated 10-year ASCVD risk (both P < 0.05). The waist-to-height ratio mediated 29.0% of the association of urinary 4-hydroxyphenanthrene with increased risk of ASCVD ( P < 0.05). The findings suggest that PAHs exposure may be associated with elevated BP and an increased risk of ASCVD. Obesity may partially mediate the association between PAHs exposure and higher BP or increased risk of ASCVD. [ABSTRACT FROM AUTHOR]

Polycyclic aromatic hydrocarbons (PAHs) associated with particulate matter (PM) may induce oxidative damage via reactive oxygen species (ROS) generation. However, the kinetics of ROS production and the link with antioxidant response induction has not been well studied. To elucidate the differences in oxidative potential of individual PAH compounds and extractable organic matter (EOM) from PM containing various PAH mixtures, we studied ROS formation and antioxidant response [total antioxidant capacity (TAC) and expression of HMOX1 and TXNRD1 ] in human alveolar basal epithelial cells (A549 cells) and human embryonic lung fibroblasts (HEL12469 cells). We treated the cells with three concentrations of model PAHs (benzo[a]pyrene, B[a]P; 3-nitrobenzanthrone, 3-NBA) and EOM from PM <2.5 μm (PM2.5). ROS levels were evaluated at 8 time intervals (30 min–24 h). In both cell lines, B[a]P treatment was associated with a time-dependent decrease of ROS levels. This trend was more pronounced in HEL12469 cells and was accompanied by increased TAC. A similar response was observed upon 3-NBA treatment in HEL12469 cells. In A549 cells, however, this compound significantly increased superoxide levels. This response was accompanied by the decrease of TAC as well as HMOX1 and TXNRD1 expression. In both cell lines, a short-time exposure to EOMs tended to increase ROS levels, while a marked decrease was observed after longer treatment periods. This was accompanied by the induction of HMOX1 and TXNRD1 expression in HEL12469 cells and increased TAC in A549 cells. In summary, our data indicate that in the studied cell lines B[a]P and EOMs caused a time-dependent decrease of intracellular ROS levels, probably due to the activation of the antioxidant response. This response was not detected in A549 cells following 3-NBA treatment, which acted as a strong superoxide inducer. Pro-oxidant properties of EOMs are limited to short-time exposure periods. [ABSTRACT FROM AUTHOR]

Some polyaromatic hydrocarbons (PAHs) and metals are known human carcinogens and the combined toxicity data of these co-contaminants are important for assessing their health risk. In this study, we have evaluated the combined genotoxicity, AhR activity and cell cycle parameters of four PAHs (benzo[a]pyrene (Ba]P), naphthalene (Nap), phenanthrene (Phe) and pyrene (Pyr)) and three metals (arsenic (As), cadmium (Cd), and lead (Pb)) in HepG2 cells using a flow cytometry based micronucleus (MN) test CAFLUX assay and nuclear fluorescence assay, respectively. The mixtures of B[a]P and metals induced a maximum of four fold increase in the MN formation compared to B[a]P alone. The higher combination of PAHs and metals did not significantly increase the MN formation. The mixtures of metals or non-carcinogenic PAHs were found to increase or decrease the aryl hydrocarbon receptor (AhR) activation of B[a]P in HepG2 cell based CAFLUX assay. Overall, the results showed that combined genotoxicity of PAHs and metals in HepG2 cells vary depending on the concentrations and number of the chemicals that are present in the mixtures and the effects of higher order combinations appear to be largely unpredictable from binary combinations. In this study, we have demonstrated the use of flow cytometry based MN test to screen the genotoxicity of environmental chemicals and its mixtures. [ABSTRACT FROM AUTHOR]

Naphthalene is a carcinogenic polycyclic aromatic hydrocarbon, to which humans are exposed as an air pollutant. Naphthalene is metabolized in humans to reactive intermediates such as 1,2-hydroxynaphthalene (1,2-NQH 2 ), 1,4-NQH 2 , 1,2-naphthoquinone (1,2-NQ), and 1,4-NQ. We examined oxidative DNA damage by these naphthalene metabolites using 32 P-labeled DNA fragments from human cancer-relevant genes. 1,2-NQH 2 and 1,4-NQH 2 induced DNA damage in the presence of Cu(II). The DNA-damaging activity of 1,2-NQH 2 was significantly increased in the presence of the reduced form of nicotinamide adenine dinucleotide (NADH), whereas that of 1,4-NQH 2 was not. In the presence of NADH, 1,2-NQ induced Cu(II)-dependent DNA damage, whereas 1,4-NQ did not. The calculated energy of the lowest unoccupied molecular orbital (LUMO), which corresponds to the reduction potential, was estimated to be −0.67 eV for 1,2-NQ and −0.75 eV for 1,4-NQ. These results suggest that 1,2-NQ was reduced more easily than 1,4-NQ. Furthermore, 1,2-NQH 2 , 1,4-NQH 2 , and 1,2-NQ plus NADH formed 8-oxo-7,8-dihydro-2′-deoxyguanosine (8-oxodG) as an oxidative DNA marker. Catalase and bathocuproine inhibited DNA damage, suggesting that H 2 O 2 and Cu(I) were involved. These results indicate that NQH 2 s are oxidized to the corresponding NQs via semiquinone radicals, and that H 2 O 2 and Cu(I) are generated during oxidation. 1,2-NQ is reduced by NADH to form the redox cycle, resulting in enhanced DNA damage. The formation of the corresponding semiquinone radicals was supported by an electron paramagnetic resonance (EPR) study. In conclusion, the redox cycle of 1,2-NQ/1,2-NQH 2 may play a more important role in the carcinogenicity of naphthalene than that of 1,4-NQ/1,4-NQH 2 . [ABSTRACT FROM AUTHOR]

Background Prenatal exposure to polycyclic aromatic hydrocarbons (PAHs) is a potential risk factor for adverse birth outcomes. Epigenetic mechanisms may play a key role in which PAHs exert its effects. Objective Our study aimed to examine whether prenatal PAH exposure was associated with adverse birth outcomes and altered DNA methylation and to explore potential mediating roles of DNA methylation. Methods Ten urinary PAH metabolites were measured from 106 pregnant women during late pregnancy in a Chinese cohort study. Cord blood DNA methylation in long interspersed nucleotide element-1 (LINE-1) and Alu repetitive elements as surrogates of global DNA methylation was analyzed by bisulfite pyrosequencing. Multivariable linear regression was used to estimate the associations of urinary PAH metabolites with birth outcomes and DNA methylation, and a mediation analysis was also conducted. Results Prenatal urinary 2-hydroxynaphthalene (2-OHNa), ∑OHNa (sum of 1- and 2-OHNa), and sum of monohydroxy-PAH (∑OH-PAHs) were associated with lower birth length (e.g., −0.80%, 95% CI: −1.39%, −0.20% for the third vs. first tertile of 2-OHNa; p for trend = 0.01). Prenatal urinary 2-OHNa and 1-hydroxyphenanthrene (1-OHPh) were associated with lower Alu and LINE-1 methylation (e.g., −1.88%, 95% CI: −3.73%, −0.10% for the third vs. first tertile tertile of 2-OHNa in Alu methylation; p for trend = 0.04). Mediation analysis failed to show a mediator effect of global DNA methylation in the association between prenatal urinary OH-PAHs and birth outcomes. Conclusions Prenatal specific PAH exposures are associated with decreased birth length and global DNA methylation. However, global DNA methylation does not mediate the associations of prenatal PAH exposure with birth outcomes. Further studies are needed to confirm the results. [ABSTRACT FROM AUTHOR]

The phytoremediation potential of 14 different plant species belonging to C3 and C4 carbon fixation pathway for soils spiked with polycyclic aromatic hydrocarbons (PAHs) such as benzo[ a ]pyrene (B[ a ]P) and pyrene (PYR) was investigated. A glasshouse experiment was conducted to measure the changes in morphological, physiological, biochemical parameters and the bioaccumulation and biodegradation ability of the plants in soils spiked with 48 and 194 mg kg −1 of B[ a ]P and PYR, respectively. The per cent removal efficacy of B[ a ]P and PYR by the tested plant species over a period of 50 days was from 6 to 26% and 14 to 40% respectively. The maximum removal of both B[ a ]P and PYR was observed in Sudan grass (C4), vetiver (C4), maize (C4), and sunflower (C3). In terms of accumulation in root and shoot, the concentration of PYR was higher in both C3 and C4 plant species when compared to B[ a ]P. Overall the results indicated that C4 plants were more efficient than their C3 counterparts in terms of morphological, physiological, biochemical and degradation ability of PAHs. [ABSTRACT FROM AUTHOR]

Background Exposure to polycyclic aromatic hydrocarbons (PAHs) has been associated with lung function decline. However, the underlying mechanisms for the association remain unclear. Objectives To explore potential role of a lung epithelial biomarker, Club cell secretory protein (CC16), in associations between PAH exposures and lung function decline. Methods We investigated 3384 adults from the Wuhan-Zhuhai cohort, and followed up at three years after first examination. Linear mixed models was used to quantify dose-response relationships between urinary monohydroxylated PAH metabolites (OH-PAHs) and lung function, as well as OH-PAHs and plasma CC16. Mediation analysis was conducted to investigate role of CC16 in the association between OH-PAHs and lung function. We also estimated the relationships between OH-PAHs and lung function change in three years among participants with different levels of CC16. Results Each 1-unit increase of log-transformed total urinary high and low molecular weight OH-PAHs (∑ HMW OH-PAH and ∑ LMW OH-PAHs) were associated with a 22.59 and 25.25 ml reduction of FEV 1 respectively, while ∑ HMW OH-PAH was associated with a 30.38 ml reduction of FVC. Moreover, these negative associations between OH-PAHs and lung function levels were significant only among low CC16 group (< 15.83 ng/ml). CC16 concentration decreased monotonically with increased high molecular weight OH-PAHs (∑ HMW OH-PAHs) when ∑ HMW OH-PAH concentration was over 0.67 μg/mmol Cr. CC16 mediated 22.13% of the association between ∑ HMW OH-PAH and FVC among individuals with higher ∑ HMW OH-PAH. After three years of follow-up, subjects with low level of plasma CC16 had a significant decline of FVC when exposed to high level of ∑ HMW OH-PAH. Conclusions CC16 play an important role in the association between high molecular weight PAHs and FVC. Individuals with low plasma CC16 level might suffer a decline in lung function when exposed to high level of high molecular weight PAHs. [ABSTRACT FROM AUTHOR]

Polycyclic aromatic hydrocarbons (PAHs) contamination in aquatic system is of concern since it may constitute a sink of these contaminants for wetland ecosystem. We investigated pollution characteristics and ecological risks of PAHs by sampling contaminated sediments and water from the Shadegan wetland in Khuzestan province, south-west Iran. Concentrations of total PAHs in water and sediment samples varied from 42 ± 2.3–136 ± 7.5 ng/L and 10 ± 0.5–317 ± 14.3 µg/kg, respectively. Source apportionment of PAHs by both approaches (Principal component analysis-multiple linear regression (PCA-MLR) and molecular isomeric ratios of specific PAHs), indicated impact of potential anthropogenic PAH sources including oil spill and incomplete combustion, bulrush combustion, vehicular exhaust and fishing boat emissions. Comparing the PAHs concentration with sediments quality guidelines based on the effect range low values/effects range-median values (ERL/ERM) and the threshold effect levels/probable effect levels (TEL/PEL). Also, a risk quotient (RQ) was elaborated for evaluation of potential toxic effects on aquatic ecosystem. Our data showed relatively insignificant adverse impact for most individual compounds. The toxic equivalent quantity (TEQ) was also calculated to estimation the PAHs toxicity. TEQ value of PAHs (1.9 µg/kg) was lower than the safe level (600 µg/kg). The fugacity fraction approach was applied to explain the trend of the selected PAHs for water–sediment exchange, which showed that the fluxes for most priority PAHs were from water to sediment suggesting no secondary source impact. [ABSTRACT FROM AUTHOR]

The Vallona lagoon is a transitional area located in the Po River delta (NE, ITALY) traditionally exploited for Manila clam ( Ruditapes philippinarum ) farming. During 2007–2008, a pipeline was buried in the middle of the lagoon to connect an off-shore structure to facilities on land. PAH levels were monitored in Manila clams and sediments before, during and after the pipeline construction to assess the impact of the activities through the pattern of distribution of the PAH compounds. PAH bioaccumulation in clams displayed seasonal fluctuations with higher levels in autumnal and wintry surveys than in spring-summer. Principal component analysis applied to PAHs in clams highlighted a petrogenic input during ante operam period and a pyrolytic origin during the burying activities. On the contrary, sediment PAH concentrations resulted quite similar both among sites and periods. Biota-Sediment-Accumulation-Factor values also confirmed that sediments were not the major source of PAH pollution for clams in this study. The welfare of clams was examined through two physiological indices (condition index and survival in air) to check the effects of the activities on a commercial resource. Both physiological indices exhibited seasonal variations connected to natural endogenous and exogenous factors; however survival in air was the most sensitive index in highlighting the effects of the pipeline burying activities. Finally, to ensure that PAH bioavailability assessment was not affected by seasonal variation of soft tissues of molluscs, PAHs/shell weight index was applied. Higher levels of this index were observed before and during the burying activities, whilst, after that, values significantly lowered. Moreover, the normalization enabled us to highlight the PAH uptake from clams in some particular periods and to compare different populations in a long-term biomonitoring program with data obtained from different periods of the year. [ABSTRACT FROM AUTHOR]

The contamination of agricultural crops by polycyclic aromatic hydrocarbons (PAHs) has drawn considerable attention due to their carcinogenicity, mutagenicity, and toxicity. However, the uptake process of PAHs in plant roots has not been clearly understood. In this work, we first study the radial uptake of phenanthrene in hydroculture wheat roots by vacuum-infiltration-centrifugation method. The concentration-dependent kinetics of apoplastic and symplastic uptake at phenanthrene concentrations of 0–6.72 μM for 4 h can be described with the Langmuir and Michaelis-Menten equations, respectively; whereas, their time-dependent kinetics at 5.60 μM phenanthrene for 36 h follow the Elovich equation. The apoplastic and symplastic uptake increases with temperature of 15–35 °C. The apparent Arrhenius activation energies for apoplastic and symplastic uptake are 77.5 and 9.39 KJ mol −1 , respectively. The symplastic uptake accounts for over 55% of total phenanthrene uptake, suggesting that symplast is the dominant pathway for wheat root phenanthrene uptake. Larger volume of symplast in roots and lower activation energy lead to the greater contribution of symplast to total uptake of phenanthrene. Our results provide not only novel insights into the mechanisms on the uptake of PAHs by plant roots, but also the help to optimize strategies for crop safety and phytoremediation of PAH-contaminated soil/water. [ABSTRACT FROM AUTHOR]

Total suspended particulate matter (TSP) was collected during the summer and winter in five Japanese cities spanning Hokkaido to Kyushu (Sapporo, Kanazawa, Tokyo, Sagamihara and Kitakyushu) from 1997 to 2014. Nine polycyclic aromatic hydrocarbons (PAHs) with four to six rings, including pyrene (Pyr) and benzo[ a ]pyrene (BaP), were identified using high-performance liquid chromatography (HPLC) with fluorescence detection. Two nitropolycyclic aromatic hydrocarbons (NPAHs), 1-nitropyrene (1-NP) and 6-nitrobenzo[ a ]pyrene (6-NBaP), were identified by HPLC with chemiluminescence detection. A comparison of PAH and NPAH concentrations and [NPAH]/[PAH] ratios such as [1-NP]/[Pyr] and [6-NBaP]/[BaP] revealed the following characteristics in the five cities: (1) In Sapporo, Kanazawa, Tokyo and Sagamihara, the concentrations of PAHs and NPAHs were high at the beginning of the sampling period and then steadily decreased, with NPAHs decreasing faster than PAHs. The large initial [1-NP]/[Pyr] ratios suggest that the major contributor was automobiles but subsequent decreases in this ratio suggest decreased automobile contributions. (2) By contrast, PAH concentrations in Kitakyushu did not decrease during the sampling period, though concentrations of NPAHs decreased. The consistently smaller [1-NP]/[Pyr] ratio and larger [6-NBaP]/[BaP] ratio in Kitakyushu suggests that the major contributor of PAHs was not automobiles but iron manufacturing which uses a large amount of coal. The sudden increase in atmospheric PAH concentrations in the winter of 2014 may also be due to iron manufacturing. [ABSTRACT FROM AUTHOR]

Benzanthrone (BNZ) is a polycyclic aromatic hydrocarbon found in industrial effluent causing skin, respiratory, gastrointestinal, genitourinary, nervous and hemopoietic toxicity. While its toxicity has been well studied, its metabolism in humans has not been investigated. The aim of this study was to characterize species differences in the in vitro metabolism of BNZ in rat and human liver microsomes and to identify the CYP isoforms involved in its metabolism. Upon incubation in liver microsomes, BNZ was found to be a direct substrate of phase I metabolism in both rat and human, undergoing oxidation and reduction. The K m in rat, 11.62 ± 1.49 μM, was two-fold higher than humans (5.97 ± 0.83 μM) suggesting higher affinity for human CYPs. Further, incubation with human rCYPs, BNZ was found to be substrate of multiple CYPs. The predicted in vivo hepatic clearance was 63.55 and 18.91 mL/min/kg in rat and human, respectively, indicating BNZ to be a high clearance compound. BNZ was found to be a moderate inhibitor of human CYP1A2. BNZ metabolism by multiple CYPs indicates that single enzyme genetic polymorphism is unlikely to have profound effect on the toxicokinetics of BNZ and default uncertainty factor of 3.16 might be sufficient to capture the intraspecies kinetic variability. [ABSTRACT FROM AUTHOR]

This study investigated a number of biomarkers, associated with systemic inflammation as well as genotoxicity, in 53 young and healthy subjects participating in a course to become firefighters, while wearing personal protective equipment (PPE). The exposure period consisted of a 3-day training course where the subjects participated in various live-fire training exercises. The subjects were instructed to extinguish fires of either wood or wood with electrical cords and mattresses. The personal exposure was measured as dermal polycyclic aromatic hydrocarbon (PAH) concentrations and urinary excretion of 1-hydroxypyrene (1-OHP). The subjects were primarily exposed to particulate matter (PM) in by-stander positions, since the self-contained breathing apparatus effectively prevented pulmonary exposure. There was increased dermal exposure to pyrene (68.1%, 95% CI: 52.5%, 83.8%) and sum of 16 polycyclic aromatic hydrocarbons (ΣPAH; 79.5%, 95% CI: 52.5%, 106.6%), and increased urinary excretion of 1-OHP (70.4%, 95% CI: 52.5%; 106.6%) after the firefighting exercise compared with the mean of two control measurements performed 2 weeks before and 2 weeks after the firefighting course, respectively. The level of Fpg-sensitive sites in peripheral blood mononuclear cells (PBMCs) was increased by 8.0% (95% CI: 0.02%, 15.9%) compared with control measurements. The level of DNA strand breaks was positively associated with dermal exposure to pyrene and ΣPAHs and urinary excretion of 1-OHP. Fpg-sensitive sites were only associated positively with PAHs. Biomarkers of inflammation and lung function showed no consistent response. In summary, the study demonstrated that PAH exposure during firefighting activity was associated with genotoxicity in PBMCs. [ABSTRACT FROM AUTHOR]

Importance Polycyclic aromatic hydrocarbons (PAH) are carcinogenic and neurotoxic combustion by-products commonly found in urban air. Exposure to PAH is disproportionately high in low income communities of color who also experience chronic economic stress. Objective In a prospective cohort study in New York City (NYC) we previously found a significant association between prenatal PAH exposure and Attention Deficit Hyperactivity Disorder (ADHD) behavior problems at age 9. Here, we have evaluated the joint effects of prenatal exposure to PAH and prenatal/childhood material hardship on ADHD behavior problems. Materials and Methods We enrolled nonsmoking African-American and Dominican pregnant women in New York City between 1998 and 2006 and followed their children through 9 years of age. As a biomarker of prenatal PAH exposure, PAH-DNA adducts were measured in maternal blood at delivery and were dichotomized at the limit of detection (to indicate high vs. low exposure). Maternal material hardship (lack of adequate food, housing, utilities, and clothing) was self-reported prenatally and at multiple time points through child age 9. Latent variable analysis identified four distinct patterns of hardship. ADHD behavior problems were assessed using the Conners Parent Rating Scale- Revised. Analyses adjusted for relevant covariates. Results Among 351 children in our sample, across all hardship groups, children with high prenatal PAH exposure (high adducts) generally had more symptoms of ADHD (higher scores) compared to those with low PAH exposure. The greatest difference was seen among the children with hardship persisting from pregnancy through childhood. Although the interactions between high PAH exposure and hardship experienced at either period (“persistent” hardship or “any” hardship) were not significant, we observed significant differences in the number of ADHD symptoms between children with high prenatal PAH exposure and either persistent hardship or any hardship compared to the others. These differences were most significant for combined high PAH and persistent hardship: ADHD Index (p < 0.008), DSM-IV Inattentive (p = 0.006), DSM-IV Hyperactive Impulsive problems (p = 0.033), and DSM-IV Index Total (p = 0.009). Conclusion The present findings add to existing evidence that co-exposure to socioeconomic disadvantage and air pollution in early life significantly increases the risk of adverse neurodevelopmental outcomes. They suggest the need for multifaceted interventions to protect pregnant mothers and their children. [ABSTRACT FROM AUTHOR]

Contaminated food and water ingestion and inhalation of polycyclic aromatic hydrocarbon are the main sources of human exposure to benzo(a)pyrene leading to cause renal injury and provoking a nephropathic response. Mangiferin is a highly potent antioxidant present in mango and known for several medicinal properties. The present study was undertaken to evaluate the renoprotective effect of mangiferin against benzo(a)pyrene induced toxicity. Benzo(a)pyrene was administered at a dose of 120.0 mg/kg once alone or in combination with mangiferin at 10.0 and 20.0 mg/kg for seven days in Swiss albino mice. Exposure to benzo(a)pyrene decreased the activities of glutathione peroxidase and increased glutathione-S-transferase level in the kidneys of mice. Moreover, DNA alkaline unwinding assay exhibit a significant decrease in F-value for the toxic control group in comparison to the normal mice, which is a marker for alteration in DNA integrity. Benzo(a)pyrene treatment also revealed an increased number of micronuclei in polychromatic erythrocytes in comparison with the control group indicating chromosomal damage in erythrocytes of bone marrow. Mangiferin pretreatment significantly improved the renal mitochondrial antioxidant status and restored the renal DNA integrity, thus demonstrating the protective effect in benzo(a)pyrene-treated mice. Dietary inclusion of mangiferin could exert protective effects against renal toxicity resulting from benzo(a)pyrene exposure. [ABSTRACT FROM AUTHOR]

Eight low-ring PAHs were detected in 21 polystyrene (PS) food contact materials (FCMs) samples while high-ring PAHs (> 4 rings) were not found. This is because the reaction pathway for formation of high-ring PAHs consists of more steps than it does for low-high PAHs. The concentrations of Σ 8 PAH were from 18.9 ± 5.16 ng/g for product colorless fruit fork to 476 ± 52.0 ng/g for foam instant noodle container. These data were far beyond levels of PAHs in other plastics. Of the eight PAHs detected, Phe had the highest average concentration, followed by Nap. These two PAHs collectively accounted for over 80% of the Σ 8 PAH concentrations in all PS FCMs. Levels of Σ 8 PAH in expanded PS FCMs were higher than those in extruded ones due to utilization of foaming agent. The concentrations of Σ 8 PAH were lower in colorless PS FCMs than in colored ones. Auxochromes and chromophores contributed to the change of short-chain hydrocarbons to aromatic hydrocarbon. Simulated migration values of PAHs from PS FCMs to food varied widely. The migration value of Σ 8 PAH with maximum probability was below 10 ng/g, which the maximum tolerated migration level for substance according to the European Union standards. However, higher migration values were possible and the potential health risk should still be concerned because the simulated migration displayed a log-normal distribution. Furthermore, water was used as food simulant would always lead to an underestimate of PAHs migration to real daily food, and then lead to an underestimate of risk. [ABSTRACT FROM AUTHOR]

Vehicle-wash wastewater (VWW) contains elevated concentrations of different petrochemicals including polycyclic aromatic hydrocarbons (PAHs), a carcinogenic group of organic compounds. This study investigates the discharge of PAHs present in the untreated wastewater of vehicle-wash stations (VWS) located in district Peshawar, Pakistan. The data obtained was being novel with the detection of 16 USEPA PAHs (both individuals and total) and compared with earlier studies and international standards. The ∑16PAHs in wastewater from light vehicle-wash stations (LVWS) and heavy vehicle-wash stations (HVWS) ranged from 245–429 μg/l and 957–1582 μg/l, respectively. A significant difference (p < 0.01) was observed in PAHs discharged from LVWS and HVWS. The projected ∑16PAHs discharge from both HVWS (92% of total generated PAHs) and LVWS (8%) was about 5109.9 g per annum. According to PAH diagnostic ratios, PAHs were both petrogenic (chrysene/benz( a )anthracene, low molecular weight/high molecular weight) and pyrogenic (phenanthrene/anthracene, fluoranthene/pyrene, fluoranthene/fluoranthene + pyrene) in origin. The highest toxic equivalent quotient (TEQ) value was shown by benzo( a )pyrene (21.6 μg/l) followed by dibenz(ah)anthracene (9.81 μg/l) in wastewater from HVWS. However, in LVWS the case was reversed with highest value (7.54 μg/l) for dibenz(ah)anthracene followed by benzo( a )pyrene (3.54 μg/l). The lowest TEQ value was indicated for phenanthrene (0.007 μg/l) in wastewater of LVWS, while pyrene showed the lowest value (0.007 μg/l) in wastewater of HVWS. The results indicated that VWS contribute significant amount of PAHs each year, which is of great concern regarding water quality, ecological and human health risk. This is the first systematic and comprehensive research related with generation of PAHs load per day, week, month and annum from VWS, their source apportionment and health effects in Pakistan. [ABSTRACT FROM AUTHOR]

Exposure concentration and inhaled dose of particles during door-to-door trips walking and using motorized transport modes (subway, bus, taxi) are evaluated along a selected route in a commercial district of Singapore. Concentrations of particles smaller than 2.5 μm in size (PM 2.5 ), black carbon, particle-bound polycyclic aromatic hydrocarbons, number of particles, active surface area and carbon monoxide have been measured in-situ using portable instruments. Simultaneous measurements were conducted at a nearby park to capture the background concentrations. The heart rate of the participants was monitored during the measurements as a proxy of the inhalation rate used to calculate the inhaled dose of particles. All measured metrics were highest and well above background levels during walking. No significant difference was observed in the exposure concentration of PM 2.5 for the three motorized transport modes, unlike for the metrics associated with ultrafine particles (UFP). The concentration of these freshly emitted particles was significantly lower on subway trips. The absence of combustion sources, use of air conditioning and screen doors at station platforms are effective measures to protect passengers' health. For other transport modes, sections of trips close to accelerating and idling vehicles, such as bus stops, traffic junctions and taxi stands, represent hotspots of particles. Reducing the waiting time at such locations will lower pollutants exposure and inhaled dose during a commute. After taking into account the effect of inhalation and travel duration when calculating dose, the health benefit of commuting by subway for this particular district of Singapore became even more evident. For example, pedestrians breathe in 2.6 and 3.2 times more PM 2.5 and UFP, respectively than subway commuters. Public buses were the second best alternative. Walking emerged as the worst commuting mode in terms of particle exposure and inhaled dose. [ABSTRACT FROM AUTHOR]

High-level, acute exposures to individual polycyclic aromatic hydrocarbons (PAHs) and complex PAH mixtures result in cardiac abnormalities in developing fish embryos. Whereas acute PAH exposures can be developmentally lethal, little is known about the later life consequences of early life, lower level PAH exposures in survivors. A population of PAH-adapted Fundulus heteroclitus from the PAH-contaminated Superfund site, Atlantic Wood Industries, Elizabeth River, Portsmouth, Virginia, United States, is highly resistant to acute PAH cardiac teratogenicity. We sought to determine and characterize long-term swimming performance and cardiac histological alterations of a subteratogenic PAH mixture exposure in both reference killifish and PAH-adapted Atlantic Wood killifish embryos. Killifish from a relatively uncontaminated reference site, King's Creek, Virginia, United States, and Atlantic Wood killifish were treated with dilutions of Elizabeth River sediment extract at 24 h post fertilization (hpf). Two proven subteratogenic dilutions, 0.1 and 1.0% Elizabeth River sediment extract (total PAH 5.04 and 50.4 µg/L, respectively), were used for embryo exposures. Then, at 5-mo post hatching, killifish were subjected to a swim performance test. A separate subset of these individuals was processed for cardiac histological analysis. Unexposed King's Creek killifish significantly outperformed the unexposed Atlantic Wood killifish in swimming performance as measured by Ucrit (i.e., critical swimming speed). However, King's Creek killifish exposed to Elizabeth River sediment extract (both 0.1 and 1.0%) showed significant declines in Ucrit. Histological analysis revealed the presence of blood in the pericardium of King's Creek killifish. Although Atlantic Wood killifish showed baseline performance deficits relative to King's Creek killifish, their pericardial cavities were nearly free of blood and atrial and ventricular alterations. These findings may explain, in part, the diminished swimming performance of King's Creek fish. Environ Toxicol Chem 2017;36:3246-3253. © 2017 SETAC [ABSTRACT FROM AUTHOR]

The objective of the present study was to determine whether the polycyclic aromatic hydrocarbons (PAHs) associated with the Deepwater Horizon ( DWH ) oil spill impacted the stress response of teleost fish. The hypothesis was that intraperitoneal (IP) treatment with PAHs associated with the DWH oil spill or waterborne exposure to DWH oil high energy water-accommodated fraction (HEWAF) would result in the downregulation of the stress response of Gulf toadfish, Opsanus beta, a benthic marine teleost fish that resides in the Gulf of Mexico. In vivo plasma cortisol levels and adrenocorticotropic hormone (ACTH)-mediated cortisol secretion by in vitro isolated kidney tissue were measured. Toadfish at rest IP-treated with naphthalene had higher plasma cortisol compared to fluorene-treated and control fish; phenanthrene-treated fish tended to have higher plasma cortisol levels that fluorene-treated and controls. When subjected to an additional crowding stress, naphthalene and phenanthrene-treated fish were no longer able to mount a stress response compared to fluorene-treated and control fish, suggesting exhaustion of the stress response. Supporting this in vivo data, there tended to be less cortisol released by the kidney in vitro from naphthalene and phenanthrene-treated fish in response to ACTH compared to controls. In contrast, toadfish at rest exposed to 3% Slick A HEWAF did not have significantly different plasma cortisol levels compared to controls. But, exposed fish did have significantly less cortisol released by the kidney in vitro in response to ACTH. When toadfish were subjected to an additional stress, there were no significant differences in plasma cortisol or ACTH, suggesting the action of a secondary secretagogue to maintain plasma cortisol in vivo . Combined, these data suggest that in response to acute PAH exposure, there may be internalization or downregulation of the melanocortin 2 receptor (MC2R) that mediates the action of ACTH. [ABSTRACT FROM AUTHOR]

Phenanthnere (PHE) is a polycyclic aromatic hydrocarbon continuously discarded in the marine environment and bioavailable to many aquatic species. Although studies about PHE toxicity have been documented for adult oysters, the effects on early developmental stages are poorly characterized in bivalves. In this study, the effects of PHE (0.02 and 2.0 μg.L −1 ) were evaluated on the embryogenesis and larval development of Crassostrea gigas . Toxicity bioassays, growth and deformities assessment, analysis of shell calcium abundance and transcript levels of genes related to xenobiotic biotransformation ( CYP2AU2 , CYP30C1 ), immune system ( Cg-Tal ) and tissue growth and shell formation ( Ferritin , Insulin-like, Cg-Try , Calmodulin and Nacrein ) were assayed in D-shape larvae after 24 h of PHE exposure. At the highest concentration (2.0 μg.L −1 ), PHE decreased the frequency of normal development (19.7 ± 2.9%) and shell size (53.5 ± 2.8 mm). Developmental deformities were mostly related to abnormal mantle and shell formation. Lower calcium levels in oyster shells exposed to PHE 2.0 μg.L −1 were observed, suggesting effects on shell structure. At this same PHE concentration, CYP30C1 , Cg-Tal , Cg-Tyr , Calmodulin were upregulated and CYP2AU2 , Ferritin , Nacrein , and Insulin-Like were downregulated compared to control larvae. At the lowest PHE concentration (0.02 μg.L −1 ), it was observed a minor decrease in normal larval development (89,6 ± 6%) and the remaining parameters were not affected. This is the first study to provide evidences that exposure to PHE can affect early oyster development at the molecular and morphological levels, possibly threatening this bivalve species. [ABSTRACT FROM AUTHOR]

Coastal upwelling prevails in the coast of Hainan Island, the northern South China Sea (SCS) during summer. We studied the influences of the upwelling on the horizontal and vertical transport of terrigenous polycyclic aromatic hydrocarbons (PAHs). PAHs in dissolved and suspended particulate phase of water samples were determined in the upper (depth < 1 m) and water column (depth > 10 m). PAH levels decreased sharply from inshore to offshore to open sea. The results showed that terrestrial input was the main source of coastal PAHs. Perylene, an important indicator of land plant-derived PAH, showed the significant correlation with PAHs (p < 0.005). This implied that fluvial transport was the primary pathway of terrigenous PAHs into the coast of northern SCS. Variations of the concentrations, compositions and diagnostic ratios of PAHs, accompanied the partition equilibrium in the water column, could indicate the selective degradation of PAHs by the plankton affected by upwelling. Different from the “traditional” transport pathway of PAHs in the water column (surface enrichment-depth depletion distribution), the upwelling could provide the original driver to elevate the upward diffusion of sediment entrained contaminants towards the intermediate even the upper waters. It could also enhance the outward diffusion of terrigenous PAHs accompanied by the offshore transport of the upper waters. Therefore, the transport pathway of PAHs can be summarized by the coastal upwelling rising PAHs with their subsequent transport offshore and settling in the adjacent open sea. [ABSTRACT FROM AUTHOR]

A carcinogenic risk assessment of polycyclic aromatic hydrocarbons in soils and sediments was conducted using the probabilistic approach from a national perspective. Published monitoring data of polycyclic aromatic hydrocarbons present in soils and sediments at different study points across India were collected and converted to their corresponding BaP equivalent concentrations. These BaP equivalent concentrations were used to evaluate comprehensive cancer risk for two different age groups. Monte Carlo simulation and sensitivity analysis were applied to quantify uncertainties of risk estimation. The analysis denotes 90% cancer risk value of 1.770E−5 for children and 3.156E−5 for adults at heavily polluted site soils. Overall carcinogenic risks of polycyclic aromatic hydrocarbons in soils of India were mostly in acceptance limits. However, the food ingestion exposure route for sediments leads them to a highly risked zone. The 90% risk values from sediments are 7.863E−05 for children and 3.999E−04 for adults. Sensitivity analysis reveals exposure duration and relative skin adherence factor for soil as the most influential parameter of the assessment, followed by BaP equivalent concentration of polycyclic aromatic hydrocarbons. For sediments, biota to sediment accumulation factor of fish in terms of BaP is most sensitive on the total outcome, followed by BaP equivalent and exposure duration. Individual exposure route analysis showed dermal contact for soils and food ingestion for sediments as the main exposure pathway. Some specific locations such as surrounding areas of Bhavnagar, Raniganj, Sunderban, Raipur, and Delhi demand potential strategies of carcinogenic risk management and reduction. The current study is probably the first attempt to provide information on the carcinogenic risk of polycyclic aromatic hydrocarbons in soil and sediments across India. [ABSTRACT FROM AUTHOR]

A personal inhalation exposure and cancer risk assessment of rural residents in Lampang, Thailand, was conducted for the first time. This highlighted important factors that may be associated with the highest areal incidence of lung cancer. Personal exposure of rural residents to polycyclic aromatic hydrocarbons (PAHs) and their nitro-derivatives (NPAHs) through inhalation of fine particulate matter (PM) was investigated in addition to stationary air sampling in an urban area. The personal exposure of the subjects to PM ranged from 44.4 to 316 μg/m, and the concentrations of PAHs (4.2-224 ng/m) and NPAHs (120-1449 pg/m) were higher than those at the urban site, indicating that personal exposure was affected by microenvironments through individual activities. The smoking behaviors of the rural residents barely affected their exposure to PAHs and NPAHs compared to other sources. The most important factor concerning the exposure of rural populations to PAHs was cooking activity, especially the use of charcoal open fires. The emission sources for rural residents and urban air were evaluated using diagnostic ratios, 1-nitropyrene/pyrene, and benzo[ a]pyrene/benzo[ ghi]perylene. Their analyses showed a significant contribution to emission from residents' personal activities in addition to the atmospheric environment. Furthermore, the personal inhalation cancer risks for all rural subjects exceeded the USEPA guideline value, suggesting that the residents have a potentially increased cancer risk. The use of open fires showed the highest cancer risk. A reduction in exposure to air pollutants for the residents could potentially be achieved by using clean fuel such as liquid petroleum gas or electricity for daily cooking. [ABSTRACT FROM AUTHOR]

We investigated the associations between exposure to polycyclic aromatic hydrocarbons (PAHs) and selected respiratory physiologic measures in cycles 2 and 3 of the Canadian Health Measures Survey, a nationally representative population sample. Using generalized linear mixed models, we tested the association between selected PAH metabolites and 1-second forced expiratory volume (FEV 1 ), forced vital capacity (FVC), and the ratio between the two (FEV 1 /FVC) in 3531 people from 6 to 79 years of age. An interquartile change in urinary PAH metabolite was associated with significant decrements in FEV 1 and FVC for eight PAHs, 2-hydroxynapthalene, 1-, and 2-hydroxyphenanthrene, 2-, 3-, and 9-hydroxyfluorene and 3- and 4-hydroxyphenanthrene. Exposure to PAH may negatively affect lung function in the Canadian population. [ABSTRACT FROM AUTHOR]

Studies of polycyclic aromatic hydrocarbons (PAHs) and its metabolites in PM10, soils, rat livers and cattle urine in Kumasi, Ghana, revealed high concentrations and cancer potency. In addition, WHO and IARC have reported an increase in cancer incidence and respiratory diseases in Ghana. Human urine were therefore collected from urban and control sites to: assess the health effects associated with PAHs exposure using malondialdehyde (MDA) and 8-hydroxy-2-deoxyguanosine (8-OHdG); identify any association between OH-PAHs, MDA, 8-OHdG with age and sex; and determine the relationship between PAHs exposure and occurrence of respiratory diseases. From the results, urinary concentrations of the sum of OH-PAHs (∑OHPAHs) were significantly higher from urban sites compared to the control site. Geometric mean concentrations adjusted by specific gravity, GM SG , indicated 2-OHNaphthalene (2-OHNap) (6.01 ± 4.21 ng/mL) as the most abundant OH-PAH, and exposure could be through the use of naphthalene-containing-mothballs in drinking water purification, insect repellent, freshener in clothes and/or “treatment of various ailments”. The study revealed that exposure to naphthalene significantly increases the occurrence of persistent cough (OR = 2.68, CI: 1.43–5.05), persistent headache (OR = 1.82, CI: 1.02–3.26), tachycardia (OR = 3.36, CI: 1.39–8.10) and dyspnea (OR = 3.07, CI: 1.27–7.43) in Kumasi residents. Highest level of urinary 2-OHNap (224 ng/mL) was detected in a female, who reported symptoms of persistent cough, headache, tachycardia, nasal congestion and inflammation, all of which are symptoms of naphthalene exposure according to USEPA. The ∑OHPAHs, 2-OHNap, 2-3-OHFluorenes, and -OHPhenanthrenes showed a significantly positive correlation with MDA and 4-OHPhenanthrene with 8-OHdG, indicating possible lipid peroxidation/cell damage or degenerative disease in some participants. MDA and 8-OHdG were highest in age group 21–60. The present study showed a significant sex difference with higher levels of urinary OH-PAHs in females than males. [ABSTRACT FROM AUTHOR]

Phenanthrene (Phe) is one of the most abundant Polycyclic aromatic hydrocarbons (PAHs) contamination from various ambient sources, which has a tremendous impact on public health. However, our knowledge regarding its effects on skin remains limited. In this study, we investigated the metabolite profiling of the human keratinocytes HaCaT cells after Phe exposure to understand the toxic effects of Phe exposure on skin. To obtain a broad picture of metabolome with various hydrophilicity, a cross-platform approach with GC–MS and UHPLC–QTOF-MS has been employed. Data were analyzed by multivariate statistical analysis and samples were separated successfully using supervised PLS-DA models. It was shown that the impacts of Phe exposure on HaCaT cells were both dose-related and time-related. A total of 48 Phe-regulated metabolites were identified and among which 19 were confirmed by reference standards. By pathway analysis, amino acid metabolism, glutathione metabolism and glycerophospholipid metabolism were highlighted as the major metabolic pathways disturbed by Phe. Furthermore, it was found that the mechanisms included a reduced amino pool and a reduced antioxidant status. Overall, these results aid in improving understanding of the dermal toxicology related to Phe, and demonstrate this cross-platform approach is suitable for metabolomics researches on HaCaT cells. [ABSTRACT FROM AUTHOR]

Biological and chemical endpoints were measured in white sucker collected downstream of Athabasca oil sands developments (AB, Canada) and compared with those at Calling Lake (AB, Canada), a reference location upstream of the Athabasca oil sands deposit. Naphthenic acid concentrations were also measured at 14 sites in the Athabasca River watershed. Concentrations of naphthenic acids were elevated in tributaries adjacent to oil sands mining developments. Tributary naphthenic acid profiles were more similar to aged oil sands process water than samples from the Athabasca River, suggesting an influence of tailings in the tributaries. White sucker showed higher energy storage in the Athabasca River as indicated by significantly higher condition and liver size. White sucker were not investing that energy into reproductive effort as measured by gonad size and fecundity, which were significantly reduced relative to the reference location. White sucker showed increased exposure to polycyclic aromatic hydrocarbons as indicated by hepatic cytochrome P4501A (CYP1A) activity and fluorescent bile metabolites, as well as higher concentrations of naphthenic acids in bile. Cadmium, copper, nickel, and selenium were also elevated in white sucker liver tissue compared with the reference location. Based on the exposure profile and response pattern observed, effects on energy storage and utilization in white sucker from the Athabasca River most likely resulted from exposure to polycyclic aromatic hydrocarbons derived from petrogenic and pyrolytic sources. Environ Toxicol Chem 2017;36:2058-2067. © 2017 SETAC [ABSTRACT FROM AUTHOR]

To illustrate chemical characteristic of PM 2.5 emission and assess inhalational carcinogenic risk of domestic Chinese cooking, 5 sets of duplicate cooking samples were collected, using the most used 5 types of oil. The mass abundance of 14 elements, 5 water-soluble ions, organic carbon (OC), elemental carbon (EC) and 11 polycyclic aromatic hydrocarbons (PAHs) were calculated; the signature and diagnostic ratio of cooking in the domestic kitchen were analyzed; and carcinogenic risks of heavy metals and PAHs via inhalation were assessed in two scenarios. The analysis showed that OC was the primary composition in the chemical profile; Na was the most abundant element that might be due to the usage of salt; Cr and Pb, NO 3 − and SO 4 2- , Phe, FL and Pyr were the main heavy metals/water-soluble ions/PAHs, respectively. Phe and FL could be used to separate cooking and stationary sources, while diagnostic ratios of BaA/(BaA + CHR), BaA/CHR, BaP/BghiP and BaP/BeP should be applied with caution, as they were influenced by various cooking conditions. Carcinogenic risks of heavy metals and PAHs were evaluated in two scenarios, simulating the condition of cooking with no ventilation and with the range hood on, respectively. The integrated risk of heavy metals and PAHs was 2.7 × 10 −3 and 5.8 × 10 −6 , respectively, during cooking with no ventilation. While with the usage of range hood, only Cr(VI), As and Ni might induce potential carcinogenic risk. The difference in the chemical abundance in cooking sources found between this and other studies underlined the necessity of constructing locally representative source profiles under real conditions. The comparison of carcinogenic risk suggested that the potentially adverse health effects induced by inorganic compositions from cooking sources should not be ignored. Meanwhile, intervention methods, such as the operation of range hood, should be applied during cooking for health protection. [ABSTRACT FROM AUTHOR]

This study evaluates the risk assessment approach currently employed for polycyclic aromatic hydrocarbon (PAH)-contaminated media, wherein carcinogenic hazards are evaluated using a dose-addition model that employs potency equivalency factors (PEFs) for targeted carcinogenic PAHs. Here, MutaMouse mice were subchronically exposed to PAH mixtures (p.o.), and mutagenic potency (MP) values were determined for five tissues. Predicted dose-additive mixture MPs were generated by summing the products of the concentrations and MPs of the individual targeted PAHs; values were compared to the experimental MPs of the mixtures to evaluate dose-additivity. Additionally, the PEF-determined BaP-equivalent concentrations were compared to those determined using a bioassay-derived method (BDM) (i.e., an additivity-independent approach). In bone marrow, mixture mutagenicity was less than dose-additive and the PEF-method provided higher estimates of BaP-equivalents than the BDM. Conversely, mixture mutagenicity in site-of-contact tissues (e.g., small intestine) was generally more than dose-additive and the PEF-method provided lower estimates of BaP-equivalents than the BDM. Overall, this study demonstrates that dose-additive predictions of mixture mutagenic potency based on the concentrations and potencies of a small number of targeted PAHs results in values that are surprisingly close to those determined experimentally, providing support for the dose-additive assumption employed for human health risk assessment of PAH mixtures. [ABSTRACT FROM AUTHOR]