Polycyclic Aromatic Hydrocarbons Burden Research Articles

Spatial and individual factors mediate the tissue burden of polycyclic aromatic hydrocarbons in adult and chick brown pelicans in the northern Gulf of Mexico

The northern Gulf of Mexico supports a substantial level of oil and gas extraction in marine waters and experiences acute and chronic exposure to marine pollution events. The region also supports a diverse array of breeding and migratory seabirds that are exposed to these pollutants during foraging and other activities. Among the pollutants of highest concern within the region are polycyclic aromatic hydrocarbons (PAHs) which tend to be toxic, carcinogenic, mutagenic, or teratogenic. We assessed PAH loads in blood from adult brown pelicans and from feathers of adults and chicks of brown pelicans in relation to individual (e.g., body condition, sex) and spatial (e.g., breeding location within the Gulf, home range size, migration distance) factors. Of the 24 PAHs assessed, 17 occurred at least once among all samples. There were no PAHs found in chicks that were not also found in adults. Alkylated PAHs occurred more commonly and were measured at higher summed concentrations compared to parent PAHs in all samples, indicating that exposure to oil and/or byproducts of oil may have been a substantial source of PAH contamination for brown pelicans during this study. Within adults, PAHs were more likely to occur, and to increase in concentration, in blood samples of females compared to males, although no difference was found in feather samples. We also found that occurrence of and concentration of PAHs increased in adults that migrated longer distances. In adults and chicks, the background levels of oil and gas development within the region of the colony was not a consistent predictor of the presence of or concentration of PAHs. We also found correlations of PAHs with hematological and biochemical biomarkers that suggested compromised health. Our results indicate that both short- and long-term exposure (i.e., blood and feathers, respectively) are occurring for this species and that even nest-bound chicks can accumulate high levels of PAHs. Long-term tracking of PAHs, as well as an assessment of sublethal effects of PAHs on pelicans, could enhance our understanding of the persistence and effects of this contaminant in the northern Gulf as could increasing the breadth of species studied.

Biomonitoring of polycyclic aromatic hydrocarbons (PAHs) by Murraya paniculata (L.) Jack in South Kolkata, West Bengal, India: spatial and temporal variations.

Attempts have been made in the present study for ascertaining the concentrations of atmospheric polycyclic aromatic hydrocarbons (PAHs) using passive biosamplers in preference to conventional air sampling methods. Mechanical stirring, sonication, Soxhlet technique and microwave-assisted Soxhlet extraction (MASE) were employed to extract PAHs from an evergreen plant (Murraya paniculata) leaves (having long life-span) sampled from polluted places of South Kolkata, India, with dense population and heavy traffic. Effects of extraction methods and operational parameters (solvent and time) on the recovery levels of PAHs were also investigated. Purified extracts, acquired through adsorption chromatography, were subjected to GC-MS and HPLC-UV analyses for qualitative and quantitative assessment of PAHs. Spatio-temporal distribution of accumulated PAHs across the sampling sites was monitored over premonsoon, postmonsoon and winter supported by pollutant source characterization. The results displayed that the extraction yields of Soxhlet (272.07 ± 26.15μgg-1) and MASE (280.17 ± 15.46μgg-1) were the highest among the four techniques. Conditions of extraction with toluene for 6h were found to be most favorable for PAHs. In spatio-temporal analysis, total concentrations of PAHs in the foliar samples varied from 200.98 ± 2.72 to 550.79 ± 10.11μgg-1 dry weight, and the highest values being recorded in the samples of Exide More because of daylong inexorable traffic flow/crowding increasing the burden of ambient PAHs. Widespread changes in meteorology exerted influence on seasonal concentrations of PAHs in plant leaves, and extent of leaf contamination by PAHs was observed extreme in winter followed by postmonsoon and then, premonsoon. Foliar accretion of PAHs differed in the study sites with diverse sources of emission from motor vehicles, fossil fuel and biomass burning along with other human interferences.

Associations of exposure to polycyclic aromatic hydrocarbons and kidney stones in U.S. general population: results from the National Health and Nutrition Examination Survey 2007-2016.

It has been reported that polycyclic aromatic hydrocarbons (PAHs) exposure was associated with the increasing risk of various diseases. Utilizing the data from the general population of the U.S., we tried to assess the association between PAHs exposure and KS. The dataset was extracted from National Health and Nutrition Examination Survey (NHANES) 2007-2016. The hydroxylated metabolites of polycyclic aromatic hydrocarbons (OH-PAHs) were detected as representative of urinary PAHs. Ranking-based PAHs score was used to evaluate the total PAHs exposure burden. Multivariable logistic regression analyses were performed to assess the association between PAHs exposure and KS after adjusting a series of confounding factors. 8975 eligible participants were included. In multivariable logistic regression analyses, after adjusting confounding variables, 2-hydroxynaphthalene (OR 1.38, 1.16-1.65; p = 0.038) and 9-hydroxyfluorene (OR 1.39, 1.06-1.84, p = 0.019) were still observed to have significant positive correlations with the prevalence of KS, respectively. The incidence of KS increased significantly with the increase of total PAHs burden (p for trend = 0.011). Significant interaction effects were observed in the subgroup of gender (p for interaction < 0.05). Among female participants, PAHs exposure was more significantly correlated with KS. Higher 2-hydroxynaphthalene (OR 1.94, 1.39-2.70; p < 0.001), 1-hydroxyphenanthrene (OR 1.57, 1.07-2.30; p = 0.022) and 2-hydroxyphenanthrene (OR 1.85, 1.11-3.06; p = 0.018) were significantly associated with the increased incidence of KS in women. There is a significant association between a high level of PAHs exposure and increased prevalence of KS. In particular, in the female population, the relationship between PAHs exposure and KS is especially significant.

Disruption of Estrogenic and Androgenic Bioactivities in Human Fetuses Exposed to Maternal Smoking

Endocrine disruptors (EDs) interfere with hormonal signalling and, given that multiple developmental processes are hormone-driven, the prenatal period is a window of increased sensitivity. Maternal smoking is a real-life model of in utero exposure to a complex mixture of EDs. Cigarette smoke contains of >7,000 pollutants, including polycyclic aromatic hydrocarbons (PAHs), which are AhR ligands and cross-talk with the estrogen receptor (ER) system. Prenatal exposure to cigarette smoke is associated with adverse outcomes, including intrauterine growth restriction and increased risk of metabolic syndrome later in life. We aimed to evaluate ED effects associated with smoke exposure in human fetuses. Fetal tissues (plasma, n=48; placenta, n=30; liver, n=29) from elective terminations of normally progressing pregnancies, ranging from 10 to 20 gestation weeks, were collected (SAFeR and FEGO studies: REC 15/NS/0123, REC 04/S0802/21). PAHs and PAH-like compounds were extracted from placenta and fetal liver. Bioactivity levels in plasma, placenta and liver extracts were determined using ER and androgen receptor (AR) transactivation reporter gene assays. PAH burden was evaluated using the AhR-responsive DRhp-CALUX assay. Smoke exposure was associated with a 1.3-fold increase in plasma estrogenic activity. The developmental trajectory of androgenic activity was altered in plasma of smoke-exposed fetuses, with significant anti-androgenic activity in older fetuses (>16 weeks of gestation). In males, plasma androgenic activity was positively associated with testes weight and anogenital distance. In contrast, placentas from smoking mothers had significantly increased androgenic potential. Furthermore, AhR-like activity was 2.9-fold higher in smoke-exposed placentas compared to controls, and 2.3-fold higher in female compared to male fetal livers. Overall, all bioactivity levels were higher in placentas compared to fetal liver. Prenatal exposure to cigarette smoke is associated with higher placental AhR activation, indicative of increased xenotoxicants burden. We also report that smoke-exposed fetuses showed increased circulating estrogenic activity and disrupted androgenic potential, across 10-20 weeks of gestation, in both fetal plasma and placenta. This demonstrates that EDs present in cigarette smoke are able to interfere with hormonal signalling and alter dynamic endocrine activity profiles, which are critical to ensure appropriate, sex-specific, development. These ED effects are likely to disturb placental function and reprogramme fetal development and thus impacting on life-long health.

In utero exposure to phenanthrene induced islet cell dysfunction in adult mice: Sex differences in the effects and potential causes

Epidemiological studies show that the burden of polycyclic aromatic hydrocarbons in human body is associated with the occurrence of insulin resistance and diabetes. In the present study, pregnant mice were exposed to phenanthrene (Phe) at doses of 0, 60 and 600 μg/kg body weight of by gavage once every 3 days. The female F1 mice at 120 days of age showed no change in their fasting glucose levels (FGLs) but exhibited significantly decreased homeostasis model assessment (HOMA) β-cell (49% and 43%) and significantly downregulated pancreatic proinsulin gene (ins2) transcription. The downregulation of transcription factors, such as PDX1, PAX4 and FGF21, indicated impaired development and function of β-cells. The significantly reduced α-cell mass in 60 and 600 μg/kg groups, and the significantly downregulated expression of proglucagon gene gcg and ARX in the 600 μg/kg group suggested that the development and function of α-cells had been impacted. The males exhibited significantly increased FGLs (1.14- and 1.15-fold) in Phe exposed treatments and significantly elevated HOMA β-cell (3.15-fold) in the 600 μg/kg group. Upregulated ins2 transcription and FGF21 protein in male mice prenatally exposed to 600 μg/kg Phe suggested that these animals appeared compensatory enhancement in β-cell function. The reduced serum estradiol levels and downregulated pancreatic estrogen receptor α and β were responsible for the dysfunction of β-cells in the females. In the males, the significantly elevated androgen levels in the 600 μg/kg group might be related to the upregulated ins2 transcription, and the increased expression of pancreatic FGF21 further demonstrated the enhancement of β-cell potential. The results will be helpful for assessing the risk of developing diabetes in adulthood after prenatal exposure to phenanthrene.

Polycyclic aromatic hydrocarbons in green space soils in Shanghai: source, distribution, and risk assessment

The purpose of this study is to study the major sources, concentrations, and distributions of polycyclic aromatic hydrocarbons (PAHs) in three different types of green space in Shanghai. In addition, we will quantitatively assess the burden of PAHs in the soil, as well as the potential carcinogenic risk of PAHs in humans. These results will provide valuable information for soil remediation and human health risk management. A total of 166 surface soil samples were collected in parks, greenbelts, and woodlands. Soils were extracted using accelerated solvent extraction (ASE). PAHs were analyzed by gas chromatography-mass spectrometry (GC-MS). The positive matrix factorization (PMF) model was used to identify major PAH emission sources and quantitatively assess their contributions to PAHs. The incremental lifetime cancer risk (ILCR) was used to quantify the potential health risk of PAHs. The average concentrations of ∑15 PAHs are 227 ± 95 ng g−1, 1632 ± 251 ng g−1, and 1888 ± 552 ng g−1 in the woodland, park, and greenbelt soils, respectively. The PMF results show that biomass (33%), coal (21%), vehicles (17%), natural gas (14%), oil (9%), and coke (7%) are the dominant sources of PAHs in the park soils. Diesel (40%), tire debris (30%), biomass (15%), gasoline (9%), and oil (5%) are the main sources in the greenbelt soils. Biomass (48%), vehicles (37%), and coal (15%) are the main sources in the woodland soils. The ILCRs of adults and children who are exposed to PAHs in soils range from 9.53 × 10−8~1.42 × 10−5. In three types of green space in Shanghai, the dominant PAHs are high–molecular weight (HMW) compounds (≥ 4 rings). This may be due to the proximity of the sampling site to emission sources. In addition, low–molecular weight (LMW) PAHs (with 2–3 rings) are relatively unstable, and these compounds are prone to volatilization and degradation. Source identification indicates that biomass combustion is the most dominant PAH source in the park and woodland soils, while vehicles are the dominant PAH source in the greenbelt soils. The ILCRs of adults and children indicate potential health risks, and children have a greater health risk than adults.

Chronic Exposure to Environmental Level Phenanthrene Induces Non-Obesity-Dependent Insulin Resistance in Male Mice.

Epidemiological evidence shows that the body burden of polycyclic aromatic hydrocarbons (PAHs) is related to the disruption of glucose homeostasis. However, the contribution of PAHs to the development of diabetes remains poorly documented. In the current work, male Kunming mice received phenanthrene (Phe) (5, 50, and 500 ng/kg) by gavage administration once every 2 days for 28 weeks. The significant elevation of homeostasis model assessment-insulin resistance (HOMA-IR) and HOMA-β cell, accompanied by hyperinsulinemia, indicated the occurrence of insulin resistance. The suppression of the insulin receptor signaling pathway in skeletal muscle might be responsible for glucose intolerance. Under the nonobese state, the serum levels of resistin, tumor necrosis factor-α, and interleukin-6 were elevated, whereas the levels of adiponectin were reduced. These changes in adipocytokine levels were consistent with their transcription in white adipose tissue. The promoter methylation levels of Retn (encoding resistin) and Adipoq (encoding adiponectin) were inversely correlated with their mRNA levels, indicating that Phe exposure could cause the disruption of adipocytokine secretion via epigenetic modification. The results would be helpful for understanding the pathogenesis in the development of T2DM caused by nonobesogenic pollutants.

Fingerprinting characterization of sedimentary PAHs and black carbon in the East China Sea using carbon and hydrogen isotopes

In this study, we present the application of a dual-isotope approach for the source apportionment of polycyclic aromatic hydrocarbons (PAHs) and black carbon (BC) in the East China Sea (ECS). The δ13C and δ2H isotope signatures of the PAHs were determined from surface sediments collected from the ECS. A Bayesian Markov chain Monte Carlo (MCMC) model was used to the environmental source identifications with dual-isotope PAHs data. The results indicate that the coal combustion source is predominant (with average of 41%) in the ECS. Liquid fossil fuels combustion, biomass combustion, and petrogenic sources account for 23%, 20%, and 12% of the total PAH burden, respectively. Additionally, we also determine the stable and radio carbon isotopes (δ13C and Δ14C) of total BC in sediment samples of the ECS. The results demonstrate the quantitative source apportionments for different sources, reflecting the contributions of fossil fuels (coal combustion and petroleum-related emissions), biomass (C3 and C4 plants) combustion, and rock-weathering sources. The fossil combustion in BC accounts for 67%, with 23% for biomass sources, meanwhile the rock weathering source in BC is an average of 10%. These results show a remarkable similarity and extensive homologies at source apportionment of PAHs and BC in the ECS, even though some differences in source mechanisms and processes. These findings on the environmental source apportionment will provide a reference for improved emission inventories, and will help to provide guidance for the efforts to mitigate environmental pollution in the coastal areas and marginal sea.

Potential sources and health risk assessment of polycyclic aromatic hydrocarbons in street dusts of Karaj urban area, northern Iran.

In the present study chemical fingerprinting approach (isomeric ratios), a receptor-oriented model (principal component analysis with multiple linear regression, PCA/MLR) and a probabilistic health risk framework were employed to characterization, source appointment and carcinogenic risk assessment of polycyclic aromatic hydrocarbons (PAHs) in street dusts of Karaj urban area (northern Iran). Thirty street dusts samples were collected from the different functional areas in the city of Karaj and analyzed for PAHs by gas chromatography/mass spectrometry (GS/MS). The results obtained showed that ∑16PAHs concentrations varied widely from 16.2 to 1236.2 with a mean of 624μg/kg and decreased in the following order of functional areas; traffic> residential > green/park areas. PAHs profile in the majority of dust samples were dominated by 5-6 rings PAHs, accounting for 25%-95% of the total PAHs. Qualitative source apportionment using the molecular isomeric ratios indicated mixed sources of PAHs in street dusts while PCA/MLR receptor model quantitatively identified three major sources with following relative contributions to the total dust PAH burden; 51% for pyrogenic-traffic sources, 32% for traffic-stationary sources and, 16% for petrogenic sources. The results of health risk assessment based on probabilistic model indicated that at the 95% percentiles, total cancer risks for children and adults are 8.43 × 10-4 and 3.34 × 10-5, respectively which both are higher than the acceptable baseline (10-6) indicating potential carcinogenic risk for local residents. It was also revealed that dust ingestion pathway is the most important contributor to the total carcinogenic risks of PAHs for both children and adults although the cancer risk level for adults through dermal and inhalation was 10 times greater than that for children. Based on the sensitivity analysis using the Monte Carlo simulation, benzo[a]pyrene equivalent concentration, exposure duration, dermal exposure area and ingestion rate were found to be the most sensitive exposure parameters which could introduce uncertainties into the cancer risk estimated.

Source apportionment of polycyclic aromatic hydrocarbons in continental shelf of the East China Sea with dual compound-specific isotopes (δ13C and δ2H)

In this study, we firstly report the application of a dual-isotope approach for the source apportionment of polycyclic aromatic hydrocarbons (PAHs) in the East China Sea (ECS). The δ13C and δ2H isotope signatures of the PAHs were determined in the surface sediments collected from the ECS. Statistical modeling based on a Bayesian Markov chain Monte Carlo (MCMC) framework was used to the environmental dual-isotope PAH data. An end-member PAH isotope database was also compiled to account for the uncertainties and quantitative contributions on the potential PAH sources, including coal combustions, liquid fossil fuel combustions, biomass combustions and petrogenic sources. The results indicate that the PAHs in the ECS had a clear predominance of the coal combustion source (~42%). The combustion of liquid fossil fuels, biomass as well as petrogenic sources represented approximately 23%, 21%, and 11% of the total PAH burden, respectively. This study on the source apportionment of environmental PAHs will provide a reference for improvingemission inventories of the PAHs, and also give guidance for the efforts to extenuate PAH pollutions in the marginal sea.

Contributions of City-Specific Fine Particulate Matter (PM2.5) to Differential In Vitro Oxidative Stress and Toxicity Implications between Beijing and Guangzhou of China.

Growing literature has documented varying toxic potencies of source- or site-specific fine particulate matter (PM2.5), as opposed to the practice that treats particle toxicities as independent of composition given the incomplete understanding of the toxicity of the constituents. Quantifying component-specific contribution is the key to unlocking the geographical disparities of particle toxicity from a mixture perspective. In this study, we performed integrated mixture-toxicity experiments and modeling to quantify the contribution of metals and polycyclic aromatic hydrocarbons (PAHs), two default culprit component groups of PM2.5 toxicity, to in vitro oxidative stress caused by wintertime PM2.5 from Beijing and Guangzhou, two megacities in China. PM2.5 from Beijing exhibited greater toxic potencies at equal mass concentrations. The targeted chemical analysis revealed higher burden of metals and PAHs per unit mass of PM2.5 in Beijing. These chemicals together explained 38 and 24% on average of PM2.5-induced reactive oxygen species in Beijing and Guangzhou, respectively, while >60% of the effects remained to be resolved in terms of contributing chemicals. PAHs contributed approximately twice the share of the PM2.5 mixture effects as metals. Fe, Cu, and Mn were the dominant metals, constituting >80% of the metal-shared proportion of the PM2.5 effects. Dibenzo[ a, l]pyrene alone explained >65% of the PAH-shared proportion of the PM2.5 toxicity effects. The significant contribution from coal combustion and vehicular emissions in Beijing suggested the major source disparities of toxicologically active PAHs between the two cities. Our study provided novel quantitative insights into the role of varying toxic component profiles in shaping the differential toxic potencies of city-specific PM2.5 pollution.

Source apportionment of polycyclic aromatic hydrocarbons (PAHs) in the air of Dalian, China: Correlations with six criteria air pollutants and meteorological conditions

Concentrations and temporal variations of priority polycyclic aromatic hydrocarbons (PAHs) in the air from a suburban area of Dalian, China were investigated for a 1-year period to assess their sources and potential correlations with six criteria air pollutants and meteorological parameters. The total concentrations of PAHs were in the range of 4.32–112.2 ng/m3 (Mean = 52.37 ± 23.99 ng/m3). Seasonality was discovered with the PAHs following an order of winter > spring > summer > autumn. The impacts of meteorological parameters on PAH levels were season-dependent. High temperature may increase the air concentrations of 4-ring PAHs during the non-heating period, whereas high relative humidity may raise the concentrations of 3- and 4-ring PAHs during the heating period. Correlations of PAHs with criteria air pollutants, such as SO2, NO2, and O3, indicated that both fossil fuel combustion and photochemical oxidation influenced the air concentrations of PAHs. According to the source apportionment by diagnostic ratios and PMF model, coal combustion and traffic emission were estimated to be the main sources of PAHs in Dalian, followed by petroleum release and biomass burning. It was worth noting that the contribution of coal combustion to the PAH burdens increased from 26% to 45% due to the emission from domestic heating in winter. This extra emission needs a continuous concern in the future.

Integration of multi-tissue PAH and PCB burdens with biomarker activity in three coastal shark species from the northwestern Gulf of Mexico

Tissue-based burdens of polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) were integrated with ethoxyresorufin-O-deethylase (EROD) and glutathione S-transferase (GST) enzyme activity in bull (Carcharhinus leucas), blacktip (Carcharhinus limbatus), and bonnethead (Sphyrna tiburo) sharks from Galveston Bay, TX. The potential toxicity of these burdens was evaluated by calculation of toxic equivalents (TEQs). Concentrations of total PAHs (∑PAHs) were significantly greater in blacktip and bonnethead sharks than bull sharks in liver, but did not exhibit differences in muscle among species. Hepatic concentrations of ∑PAHs in these sharks (range of means: 1560–2200 ng/g wet wt.) were greater than concentrations previously reported in oysters from Galveston Bay (range of means: 134–333 ng/g dry wt.), which suggests that trophic dilution of PAHs may not be reflected in sharks. Total PCBs (∑PCBs) were significantly greatest in bull sharks and lowest in bonnetheads, while blacktips were intermediate to these species. EROD activity was greater in bonnetheads than the other species, whereas GST activity was significantly higher in blacktips and bonnetheads than in bull sharks. Integration of hepatic burdens with biomarker activity via constrained multivariate analysis found correlations for only a small number of individual PAH/PCB congeners. Hepatic TEQ measurements suggest potential physiological effects of these burdens compared to established TEQ thresholds for other taxa, although the likelihood of similar effects in sharks requires further study and the inclusion of toxic endpoints. Our findings indicate that sharks may be prone to the accumulation of PAHs and PCBs, which may result in negative health outcomes for these cartilaginous fishes.

ETS Exposure and PAH Body Burden in Nonsmoking Italian Adults.

Active smoking is associated with increased body burden of polycyclic aromatic hydrocarbons (PAHs); the aim of this study was to assess whether environmental tobacco smoking (ETS) increases the internal dose of PAHs. In 344 nonsmoking Italian adults, out of 497 individuals selected as representative of the population of the town of Modena, ETS exposure was evaluated by a self-administered questionnaire and by the measurement of urinary cotinine (COT-U). PAH exposure was assessed by the measurement of urinary 1-hydroxypyrene (1-OHPYR) and of ten urinary PAHs. In all subjects, median (5th–95th percentile) COT-U was 0.47 (<0.1–3.91) µg/L. While 58 subjects reported to be ETS exposed (ETSQUEST), 38 individuals were identified as ETS exposed on the basis of a COT-U value of 1.78 (90% confidence interval 1.75–1.80) µg/L, previously derived as an upper reference value in not ETS exposed Italian adults (ETSCOT). Median COT-U levels were 1.38 (<0.1–9.06) and 3.63 (1.80–17.39) µg/L in ETSQUEST and in ETSCOT subjects, respectively. Significant correlations between COT-U and 1-OHPYR, and urinary anthracene, fluoranthene, pyrene, and chrysene were found among all subjects. Significantly higher levels of 1-OHPYR, and urinary fluorene, anthracene, and pyrene were found in ETSCOT individuals. The results of multiple linear regression analyses, taking into consideration diet and other sources of PAHs exposures such as the residence area/characteristics and traffic, confirmed that 1-OHPYR and urinary fluorene were affected by ETS exposure, even if ETS played a minor role.

Distribution and ecological risks of polycyclic aromatic hydrocarbons (PAHs) in sediments of different tropical water ecosystems in Niger Delta, Nigeria

Sediments are considered as suitable matrices to study the contamination levels of aquatic environment since they represent a sink for multiple contaminant sources. In this study, the influence of sediment characteristics on the distribution of polycyclic aromatic hydrocarbons (PAHs) and its potential risk in euryhaline, freshwater and humic aquatic bodies of Douglas/Stubbs creek, Ikpa River and Eniong River, respectively, were investigated. The level of PAHs in sediment was quantified using GC–MS, while sediment properties including total organic carbon (TOC) content and grain size were determined by the wet oxidation and hydrometer methods, respectively. The results revealed that the total levels of PAHs in sediment varied significantly between the euryhaline, freshwater and humic freshwater ecosystems. In Ikpa River freshwater ecosystem, a total PAHs load of 1055.2 ng/g was recorded with the suites concentration ranging from 13.0 ng/g (for acenaphthylene) to 161 ng/g (for pyrene). The humic ecosystem of Eniong River had a total PAH load of 11.06 ng/g, while the suites level recorded ranged from 0.04 ng/g for acenaphthene to 2.65 ng/g for chrysene. The total level of PAHs detected in the euryhaline Douglas/Stubbs creek was 14.47 ng/g, and suite concentrations varied between 4.27 ng/g for naphthalene and 5.13 ng/g for acenaphthylene. This shows variation in quantity and quality of PAH contaminants with the nature of ecosystems. It implies complex and diverse contamination sources as well as different capabilities to recover from PAH contamination. Correlation analysis has shown that sediment particle and TOC content influenced PAHs burden in bottom sediments, but the effects varied with the molecular weight of PAHs and the nature of the ecosystems. The TOC was the most significant determinant of PAHs load and distribution in sediment of the freshwater Ikpa River and euryhaline Douglas/Stubbs but had little or no influence in the humic sediment of Eniong River, while the influence of particle size was generally indefinite but slightly associated with PAHs accumulation in the euryhaline sediment. Generally, the total PAH levels (11.0–1055.2 ng/g) recorded were low and below the allowable limit for aquatic sediments. The ecological risk assessment revealed that these levels were lower than the effects range low and effects range medium values. This indicates no acute adverse biological effect although the accumulation of PAHs in freshwater ecosystem of Ikpa River may pose ecological risks as most of the carcinogenic PAH suites had relatively high pollution indices compared to other ecosystem types studied.

Monitoring of PAHs in the natural protected areas in non-heating season using Norway spruce (Picea abies (L.) Karst) needles

This paper presents the results of the screening investigation of the environmental burden of polycyclic aromatic hydrocarbons (PAHs) in the natural protected areas in non-heating season. Current year spruce needles were used as a bioacummulative indicator. The total exposure at 15 PAHs (2-6 rings) and carcinogenic potential of these compounds were taken as parameters describing the hazard level. Sampling, in a uniform way, was made in the Silesian Voivodeship landscape parks and the selected Polish national parks as well as in the reference sites with characteristic pattern of PAHs emission, namely in industrialized urban areas and near the expressway. The presence of PAHs, including carcinogenic ones, was shown in all the localities; their content in needles sampled in the natural protective areas was slightly diversified and ranged from 145 to 339 ng/g- (d. w.). Higher differences were observed for carcinogenic potential index (CP) which varied from 2.2 to 18.2. The analysis of PAHs profiles has shown that despite the seasonal lack of intensive emissions from domestic heating, in the majority of natural protective areas pyrogenic sources have also been identified. Profiles of PAHs found in Karkonoski and Ojcowski NPs suggest their petrogenic origin probably due to the intensive tourism (emissions from car engines) in those areas.

Polycyclic aromatic hydrocarbons in agricultural soils from Northwest Fujian, Southeast China: Spatial distribution, source apportionment, and toxicity evaluation

Polycyclic aromatic hydrocarbons (PAHs) in agricultural soils play an important role in aspects of environment safety and human health. Sixteen US-EPA priority PAHs in 78 surface agricultural soils from Nanping and Sanming, Northwest Fujian were detected to elucidate their contamination levels, spatial distribution, sources, and toxicities. The total concentrations of PAHs were 12.90–2271.03ng/g, with an average of 223.85±324.33ng/g. North and Central Nanping and Central Sanming were found to be most contaminated regions in Northwest Fujian. The spatial distribution of PAHs positively correlated with the population density in the study area. Three- and four-ring PAHs were dominant components, accounting for 45% and 34% of the total PAHs, respectively. Four sources were identified by the positive matrix factorization (PMF) model. Their contributions to the total PAHs burden were 50%, 31%, 16%, and 3% for biomass combustion, coal burning, vehicle emission, and coking, respectively. Spatial distribution of sources indicated that higher amounts of biomass-originated PAHs mainly occurred in Sanming, while higher contributions of PAHs originated from coal burning and vehicular emission were mostly found in Nanping. The mean benzo(a)pyrene equivalent (BaPeq) values were 14.95ng/g for seven carcinogenic PAHs (Σ7cPAH), and 15.20ng/g for 16 PAHs, respectively, suggesting that Σ7cPAH were the major toxic contributors to the total PAHs. Source apportionment of PAH toxicities based on PMF-BaPeq method showed that biomass, coal burning, vehicle emission, and coking source contributed 3%, 41%, 55%, and 1% to Σ16BaPeq values, respectively. Traffic source, associated with higher carcinogenic PAHs burden, posed the highest toxicity among all sources despite its low proportion of the total PAHs.

Street foods exacerbate effects of the environmental burden of polycyclic aromatic hydrocarbons (PAHs) in Nigeria.

Polycyclic aromatic hydrocarbons (PAHs) are a large group of well-known toxicants with carcinogenic potential and other health effects including on the immune system. The high health risks of non-communicable diseases and relevant comorbidities in Africa, particularly in contaminated areas like e-waste and crude oil and gas exploration areas and for high consumers of food commodity groupings which are most critical for PAH exposure, are exacerbated by dietary exposure due to unsafe practices in commonly consumed foods, like those street vended.In February 2016, 20 commonly consumed street foods were purchased directly from vendors at major bus stops in Benin City and Umunede in Nigeria. The concentration of 16 priority PAHs was determined. The dietary intake of B[a]P, ∑PAH, PAH4, PAH8, and ∑B(a)Peq was estimated for children, peripubertal children/adolescent, and adult using the total diet study (TDS) method. Among the analyzed PAHs, there was a predominance of chrysene (17.42μg/kg). Roasted yam (14.15μg/kg) and fried fish (1.40μg/kg) had the highest levels of ∑PAH and B[a]P, respectively. The mean concentration of B[a]P, ∑PAH, PAH4, PAH8, and ∑B(a)Peq ranged from 0.65-1.40μg/kg, 0.20-14.15μg/kg, 0.43-5.22μg/kg, 0.13-7.88μg/kg, and 0.002-2.123μg/kg, respectively. The mean concentration of B[a]P and PAH4 reported in this study was below the maximum allowable levels of 5 and 12μg/kg for adults and above the maximum levels for young children set at 1.0μg/kg for both B[a]P and PAH4 in food. The estimated dietary intake of B[a]P, ∑PAH, PAH4, PAH8, and ∑B(a)Peq for adult, adolescent, and children was 0.56, 0.37, and 0.31μg/day; 17.6, 10.7, and 8.81μg/day; 5.78, 4.01, and 3.26μg/day; 9.22, 6.19, and 5.09μg/day; and 1.72, 0.97, and 0.82μg/day, respectively.Street foods represent one important source of PAHs. The exposure occurring through street food compounds with that from home-made foods, environmental pollution, and lifestyle (tobacco smoke) is making up an aggregate daily exposure in the general population.The incremental lifetime cancer risk for adults and children from the consumption of street food was 7.6 × 10-8 and 2.1 × 10-8, respectively. Along with initiatives to manage environmental contamination and promote healthier lifestyle, people should be empowered on healthy cooking practices and safe food cookery environments.

Polycyclic Aromatic Hydrocarbons (PAHs) and Organochlorinated Pesticides (OCPs) in Yellowtail (Seriola lalandi) from three Spatially Distinct Locations along the Coast of South Africa: Levels, Sources and Fish Size Effec

Polycyclic aromatic hydrocarbons (PAHs) and organochlorinated pesticides (OCPs) such as dichlorodiphenyltrichloroethane (DDT), endosulfan and benzenhexachloride (BHC) were evaluated in yellowtail (Seriola lalandi) fish species. These hardous compounds were studied in fish sampled from three locations: Port Elizabeth, Yzerfontein and Struis Bay. The aim of the study was to investigate the profiles, levels and sources of PAHs and pesticides in yellowtail from the selected locations in relation to fish size and lipid content. Significant variations (p<0.05) were observed in the levels of PAHs measured in fish sampled from the three locations. Fish from Port Elizabeth had the highest PAHs concentrations (533.95 ± 34.36), followed by Yzerfontein (221.40 ± 33.03) and Struis Bay (88.97 ± 2.83) μg/kg wet weight. benzo(a)pyrene (as PAHs biomarker) exceeded the recommended EU limit (2 μg/kg) in samples from Port Elizabeth and Yzerfontein whereas samples from Struis Bay did not exceed. DDT was detected only in samples from Port Elizabeth and Yzerfontein with mean total concentrations (7.48 ± 5.18 and 11.14 ± 1.44 respectively) not significantly different. Fish size (weight) correlated positively with lipid content (0.65; p<0.01) and a stronger positive correlation with AE©PAHs (0.83; p<0.01). PAHs input source in fish from Port Elizabeth reflected a mixture of petrogenic and pyrogenic whereas, Yzerfontein and Struis Bay showed input source as petrogenic. In conclusion, consumption of large sized fish in locations with high PAHs burden can predispose consumers to health risk. Further investigation into human dietary exposure with the species is recommended.

Environmental exposure to polycyclic aromatic hydrocarbons (PAHs): The correlation with and impact on reproductive hormones in umbilical cord serum

Polycyclic aromatic hydrocarbons (PAHs) are a type of ubiquitous pollutant with the potential ability to cause endocrine disruption that would have an adverse health impact on the general population. To assess the maternal exposure to PAHs in neonates and evaluate the possible impact of PAHs on reproductive hormone levels, the concentration of PAHs and reproductive hormone levels in the umbilical cord serum of 98 mother-infant pairs in the Shengsi Islands were investigated. The median concentration of total PAHs was determined to be 164 (Inter-Quartile Range, IQR 93.6–267) ng g−1 lipid, and 68% of the PAHs were lower-molecule congeners. The highest level was found for pyrene (PYR) and naphthalene (NAP), which contributed 54.6% of all the PAHs present in the samples. The exposure to PAHs negatively affected estradiol (E2) and Anti-Mullerian hormones (AMH) and positively affected FSH in the umbilical cord serum. The result expanded the database of the human burden of PAHs and suggested that PAHs can act as a type of Endocrine-Disrupting Chemical (EDC). These results may help to understand the complex pathways involved in disorders of human reproductive health associated with prenatal exposure to PAHs.