PAH Levels Research Articles

Application of a fugacity model to estimate emissions and environmental fate of ship stack PAHs in Shanghai, China

The understandings of environmental activities and regional inventory of ship stack PAHs are very limited in Shanghai due, in part, to the lack of source-segregated analysis. To address this, measured PAHs in organic film on ship surfaces were employed to reconstruct concentrations in various compartments through a fugacity model to investigate the level, transport, fate and annual emission of ship stack PAHs in Shanghai. The results revealed that ship stack PAHs results in 11.2–181 ng L−1 and 71.0–1710 ng g−1 in water and sediment of Shanghai, respectively. After being released into air, ship stack PAHs mainly concentrated in organic films and sediments while sunk in water and sediment. Crucial mass transfer pathways include deposition of airborne and sediment PAHs. The mass loss of ship stack PAHs was primarily through air advection, followed by degradation in sediment. The ship emissions (53.7 tons annually) accounted for approximate one tenth of the regional total in Shanghai (in 2017). Additionally, shipping was estimated to release 127 tons of PAHs annually into the Shanghai section of Yangtze River. Our results suggest our fugacity-based approach can be used to estimate the regional emissions and inventory of ship stack PAHs in the surrounding environment.

Characterization for Types and Percents of Polycyclic Aromatic Hydrocarbons in Sera of Workers at Fuels Stations at Baghdad

Allpolycyclic aromatic hydrocarbons (PAHs) have a hightoxicity, and/or carcinogenic and \ormutagenic to most microorganisms andhumans.Main aim to this study is to providecontemporary information (quantitative and qualitative)PAHs in sera of fuel stations, workers whom exposure with petroleum products.The study includes 60 male petrol-filling workers in 5 petrol stations around Baghdad. Theirages were between (20 – 50) years. For compared the results a 30 sera samples from healthyindividuals was collected with corresponding age-matched as control group. The samples werecollected from October 2017 until April 2018. The BMI was calculated for all subjects.Technique of High performance liquid chromatography (HPLC) was used to detect thepresence of PAHs quantitatively and qualitatively in the sera of all subjects.The mean level of total PAHs in sera of workers was 1275.65± 934.267 higher than that forhealthy subjects 67.380 ± 46.16 with significant value p=0.033.Also the types and percent ofPAHs in the sera of workers were differ.For studying the epidemiologic,no correlation betweenthe percent of % PAHs in sera of workers who exposure to petroleum withoutaffected withtheirage and BMI.

Polycyclic aromatic hydrocarbons in airborne particulate matter samples from Hanoi, Vietnam: Particle size distribution, aryl hydrocarbon ligand receptor activity, and implication for cancer risk assessment

Concentrations and profiles of unsubstituted and methylated polycyclic aromatic hydrocarbons (PAHs and Me-PAHs) were analyzed in airborne particulate matter (PM) samples collected from high-traffic roads in Hanoi urban area. Levels of PAHs and Me-PAHs ranged from 210 to 660 (average 420) ng/m3 in total PM, and these pollutants were mainly associated with fine particles (PM2.5) rather than coarser ones (PM > 10 and PM10). Proportions of high-molecular-weight compounds (i.e., 5- and 6-ring) increased with decreasing particle size. Benzo[b+k]fluoranthene, indeno[1,2,3-cd]pyrene, and benzo[ghi]perylene were the most predominant compounds in the PM2.5 samples. In all the samples, Me-PAHs were less abundant than unsubstituted PAHs. The PAH-CALUX assays were applied to evaluate aryl hydrocarbon receptor (AhR) ligand activities in crude extracts and different fractions from the PM samples. Benzo[a]pyrene equivalents (BaP-EQs) derived by the PAH-CALUX assays for low polar fractions (mainly PAHs and Me-PAHs) ranged from 300 to 840 ng/m3, which were more consistent with theoretical values derived by using PAH-CALUX relative potencies (270–710 ng/m3) rather than conventional toxic equivalency factor-based values (22–69 ng/m3). Concentrations of PAHs and Me-PAHs highly correlated with bioassay-derived BaP-EQs. AhR-mediated activities of more polar compounds and interaction effects between PAH-related compounds were observed. By using PAH-CALUX BaP-EQs, the ILCR values ranged from 1.0 × 10−4 to 2.8 × 10−4 for adults and from 6.4 × 10−5 to 1.8 × 10−4 for children. Underestimation of cancer risk can be eliminated by using effect-directed method (e.g., PAH-CALUX) rather than chemical-specific approach.

Variation in Polycyclic Aromatic Hydrocarbon Contamination Between Native and Introduced Species of Fishes of Pallikaranai Wetland, Chennai, Tamil Nadu, India

The impacts of invasive fish species on recipient communities are mostly considered a threat to the biodiversity of freshwater systems. A characteristic of introduced species turning invasive is their higher tolerance to environmental stressors. To understand if non-native fishes in Pallikaranai wetland, Tamil Nadu, India, are more tolerant to anthropogenic pressures in the Wetland, we assessed the variation in Polycyclic Aromatic Hydrocarbon contamination between introduced and native fish species. Mean levels of Naphthalene, fluorene, phenanthrene, anthracene, pyrene, and total PAH in samples of introduced species were higher than native species, while High Molecular weight PAH and carcinogenic PAH4 were higher in native fish species. The data was also analysed to assess if co-variates (organs, seasons, and sex) affected PAH accumulation patterns in non-native species. It was observed that only organs, sex, and year contributed significantly.

Low levels of PAHs and organotin compounds in surface sediment samples from a broad marine area of 25 de Mayo (King George) Island, South Shetland Islands

The Northern region of the Antarctic Peninsula constitutes the area with the highest human presence in West Antarctica. The human presence, with all the activities associated such as logistic, scientific and tourism operations, represents a potential risk of chemical pollution with both, organic and inorganic contaminants. Under these conditions knowledge about the presence and levels of the main persistent organic pollutants (POPs) is essential to evaluate the environmental status of this ecologically relevant and sensitive area. In this work, which complements our previous study regarding trace elements, we performed the first regional-scale monitoring of 24 PAHs (16 of them included in EPA list of primary pollutant), and organotin compounds (OTCs:TBT, DBT and MBT) in surface sediment from 68 sites comprising six different areas in Maxwell Bay, southeast coast of 25 de Mayo (King George) Island. POPs were quantified in surface sediment samples (20–30 m depth) obtained during two summer Antarctic expeditions by gas chromatography–mass spectrometry (GC–MS). The two most anthropized areas (South Fildes and Potter Cove) showed moderated evidence of pollution for PAHs and OTC. In some sampling sites the concentration of total PAHs was higher than 100 ng/g dw, while TBT was detected in only five samples, two of them located in Potter Cove (ranged between 14 and 18 ng/g dw), and three, located in South Fildes area (ranged between 118 and 416 ng/g dw). Although POPs contamination was evidenced in some samples close to scientific stations, a pollution pattern was not clearly identified.

Early Outcome of Mitral Valve Replacement in Patient Having Mitral Stenosis with Moderate Pulmonary Hypertension

Background: Mitral valve replacement (MVR) plays a central role in the management of patients with mitral stenosis with moderate to severe pulmonary hypertension. Pulmonary hypertension has an impact on short term outcome of MVR. It can influence left ventricular function (low output syndrome), incidence of arrhythmia, ARDS leading to respiratory failure and right ventricular failure which may be irreversible.
 Methods: The immediate postoperative hemodynamics in 40 patients with moderate to severe pulmonary arterial hypertension who underwent mitral valve replacement (BLMV) between July 2010 and June 2012 were studied prospectively. Patients were divided into two groups: Group A (n=20): Patient having MS with moderate pulmonary hypertension (PASP: 40-59 mm-Hg) and Group B (n=20): Patient having MS with severe pulmonary hypertension (PASP e” 60mm-Hg). Total two follow up were done- 1st follow up after 10 days and 2nd follow up after 1 month of MVR. Each patient was assessed by medical history, clinical examination & color doppler echocardiogram.
 Results: It was shown that surgery can be beneficial for the patients if MVR is done in the state of mild PAH irrespective of age but beyond this level of PAH, the patients may still remain with mild pulmonary hypertension which may trigger the cascade of pulmonary vascular Disease may be the cause of unsatisfactory outcome. So, early surgical outcome of mitral stenosis with moderate pulmonary hypertension is better than mitral stenosis with severe pulmonary hypertension.
 Conclusion: We conclude that MVR in patients having MS with moderate PAH is a safe and effective measures for preventing pulmonary hypertension related complications.
 Cardiovasc. j. 2021; 13(2): 177-182

Erythropoietin alters the pharmacokinetics of organic anions mainly eliminated by the kidney in rats.

Erythropoietin (EPO) is a cytokine originally used for its effects on the hematopoietic system, and is widely prescribed around the world. In the present study, the effects of EPO administration on p-aminohippurate (PAH, a prototype organic anion) pharmacokinetics and on the renal expression of PAH transporters were evaluated. Male Wistar rats were treated with EPO or saline (control group). After 42h, PAH was administered, and plasma samples were obtained at different time points to determine PAH levels. PAH levels in renal tissue and urine were also assessed. The renal expression of PAH transporters was evaluated by Western blotting. EPO-treated rats showed an increase in PAH systemic clearance, in its elimination rate constant, and in urinary PAH levels, while PAH in renal tissue was decreased. Moreover, EPO administration increased the expression of the transporters of the organic anions evaluated. The EPO-induced increase in PAH clearance is accounted for by the increase in its renal secretion mediated by the organic anion transporters. The goal of this study is to add important information to the wide knowledge gap that exists regarding drug-drug interactions. Owing to the global use of EPO, these results are useful in terms of translation into clinical practice.

Hydrocarbon pollution in Atlantic coast of Mauritania (Levrier Bay Zone): Call for sustainable management

Levrier Bay is an important fishing area which is under growing anthropogenic pressures seriously threatening this treasure. Among these pressures Polycyclic Aromatic Hydrocarbon are of great environmental concern. Therefore, 16 EPA-PAHs were analyzed using GC–MS in Perna perna species and sediment. Comparison with Dakar (Senegal) and Moroccan coasts shows that PAHs levels are strikingly lower than that of heavily polluted Dakar coast (2474 μg/kg); nevertheless, comparable to Moroccan Casablanca and Tangier coasts (245 and 351 μg/kg, respectively). Ratio analysis indicates the predominance of pyrogenic sources and partial contribution of automotive traffic for the half of 4 sites. Furthermore, statistical analys shows that there are no significative differences, except for Benzo(b)Fluorentene in P. perna tissue and 4 PAHs (Fluorene; Fluorenthene; Pyrene; diBenzo(ah)Anthracene and dBahANT) in sediment for sites samples. Furthermore, bioconcentration indicates that P. perna is an excellent PAHs bioindicator. This points the necessity for immediate introduction of a sound Pollutants monitoring system.

The risk assessment of inorganic and organic pollutant levels in an urban area affected by intensive industry.

The city of Litvínov (North Bohemia, Czech Republic) is seriously affected by coal mining, coal processing, and intensive industrial activities. Within the urban area, the potential environmental hazard of risk elements (in soil and vegetation) and polycyclic aromatic hydrocarbons (PAHs, in soils) was estimated using selected environmental and human health hazard indices. In total, 24 sites were sampled, including the city center, residential areas, industrialized zone, and areas close to operating and/or abandoned coal mines. The results showed elevated values of As, Cd, Cu, Ni, Pb, and Zn in soils (the maximum levels of individual pollution indices varied between 3 and 5 for As, Pb, and Zn); the risk assessment code (RAC) values indicated high bioaccessibility of Cd and Zn. The high mobility of Cd was confirmed by their bioaccumulation factors (BAF) in the aboveground biomass of Taraxacum sect. Ruderalia and Polygonum aviculare, reaching up to 1.9 and 2.9, respectively. The Cd content in plants presents a substantial health hazard for herbivores such as Oryctolagus cuniculus living within the urban area. The PAH levels in the soils also showed elevated values; the contents of benzo(a)pyrene exceeded more than 2-fold the indicative values for potential health risk for biota, especially near the abandoned coal mines. The incremental lifetime cancer risks (ILCR) for ingestion of the contaminated soil showed only low or negligible cancerogenic risk, varying between 6.7 × 10-7 and 1.6 × 10-5 for children, and between 9.9 × 10-7 and 2.7 × 10-6 for adults. However, the potential health impact of the inhalation of the contaminated particulate matter should be included in the further research. Although the contamination level in the investigated area does not represent an imminent environmental and health risk, the potential remediation measures should be considered in the future.

Urinary levels of PAH metabolites in pregnant women and their correlation with sociodemographic factors and PM2.5 exposure in an urban and a suburban area

Exposure to PAHs during pregnancy is associated with adverse birth outcomes. The objectives of this study were to determine the urinary levels of PAH metabolites in pregnant women and to evaluate their association with sociodemographic and lifestyle variables and exposure to atmospheric PM2.5. Subjects of 80 non-smoking pregnant women from three regions in an urban area (Isfahan city) and one region of suburb area (Mobarakeh town) were recruited to the study. The urine samples of women were collected during their first (spring) and third (autumn) trimester of pregnancy. Urinary PAHs’ metabolites including 1-naphthol (1-NAP), 2-naphthol (2-NAP), 9-phenanthrol (9-PHN), and 1-hydroxypyrene (1-OHP) were analysed by a GC/MS after their extraction and derivatization. Ambient PM2.5 data for the study period were collected from air pollution monitoring stations. The mean urinary concentrations of 1-NAP, 2-NAP, 9-PHN and 1-HOP in spring were 3.3, 2.2, 0.9 and 8.8 μg g−1 creatinine, and those in autumn accounted for 5.2, 3.0, 11.2 and 11.3 μg g−1 creatinine, respectively. Coincidently, the mean atmospheric PM2.5 concentrations of 23.2 μg m−3 in spring and 37.3 μg m−3 in autumn were attained. The concentration of the metabolites in the urban area was higher than that in the suburban area in both seasons which was following the ambient levels of PM2.5. A significant positive correlation between the metabolites and ambient PM2.5 was observed (p value < 0.05). Although the socio-demographic factors affected the level of exposure, the difference was not statistically significant (p value < 0.05). Residents of the urban area were exposed to a higher level of PAHs due to air pollution especially in the cold season.

Ecological risk assessment of the levels of polycyclic aromatic hydrocarbons in soils of the abandoned sections of Orji Mechanic Village, Owerri, Imo State, Nigeria

BackgroundEcological risk assessment of the levels of polycyclic aromatic hydrocarbons in soils of the abandoned sections of Orji Mechanic Village, Owerri, Imo State, Nigeria. The main objective of the study was to determine the levels of soil contamination from polycyclic aromatic compounds (PAHs) due to anthropogenic events in the mechanic village before reclamation.ResultsAnalysis of soil samples revealed mean PAH levels ranging from 1.22E−02 ± 0.00 to 5.60E−02 ± 0.01 mg/kg, with higher PAH concentrations observed at 0–10 cm compared to other depths. The sum of PAHs (∑PAHs) ranged from 1.58E−01 to 6.71E−01 mg/kg, as the sum of low molecular weight PAHs (∑LPAHs) varied from 7.16E−03 to 1–1.60E−01 mg/kg, while the sum of high molecular weight PAHs (∑HPAHs) ranged from 1.81E−02 to 5.42E−01 mg/kg. The sum of carcinogenic PAHs (∑Carcino-PAHs) varied from 5.39E−01 to 9.74E−02 mg/kg, indicating elevated levels of carcinogens in the sampled soils. Diagnostic ratio, principal component, and correlation analysis of the results revealed that pyrogenic sources were primarily responsible for the observed PAHs owing to the activities of automobile mechanics in the Orji Mechanic Village. Benzo(a)pyrene equivalent (BePeq) of the PAHs indicated high carcinogenic potency for sample A. The total cancer risk was above 1 × 10–6, indicating a greater risk of cancer due to contact with the contaminated soil samples; hence, the result of this study is a serious ecological concern.ConclusionThere may be accumulation of these contaminants in the investigated area, which will eventually contaminate the groundwater as well as surface water resources. Remedial measures to prevent possible health problems due to the PAHs which results from the activities of automobile mechanics are therefore recommended.

Quantification, sources, and associated risks of 16-priority polycyclic aromatic hydrocarbons from selected land-use impacted soils

Abstract This study determined the spatial compositional occurrence, sources, and the associated risks of sixteen priority PAHs in soil depths from the selected land-use environments. Samples were collected from nine generator land-use sites in the top (0-15 cm) and sub (15-30 cm) soil depths. Sample extraction was by ultrasonication with dichloromethane/n-hexane and clean-up in silica gel/alumina packed column. The level of PAHs was determined using a gas chromatography-mass spectrometer (GC-MS). The concentrations of PAHs isomers and the Σ 16 PAHs ranged from ND to 16876 μg·kg−1, and from 346 to 44052 μg·kg−1 respectively. The Σ 16PAHs occurrence showed concentration load in the order of subsoil &gt; topsoil. The ΣPAHs concentrations exceeded the DPR-EGAPSIN target and intervention value in 91% and 11% of the samples respectively. The total cancer risk ranged from low to moderate risk-based levels. The PAHs sources were attributed to low and high petroleum combustion emissions and stationary sources around the diesel combustion electricity generator in the land-use sites. This study revealed that the land-use activities associated with diesel combustion have contributed a significant amount of Σ16PAHs to the pollution load in the land-use sites with potential for ecological and human exposure risks.

Background levels of OCPs, PCBs, and PAHs in soils from the eastern Pamirs, China, an alpine region influenced by westerly atmospheric transport

Long-range atmospheric transport (LRAT) plays a crucial role in the occurrence of persistent organic pollutants (POPs) in remote regions. When studying the LRAT of POPs on the Tibetan Plateau, westerly-controlled regions have received insufficient attention compared with regions influenced by the Indian monsoon or air flow from East Asia. We investigated the residual levels of POPs in soils from the eastern Pamirs and used air backward trajectory analysis to elucidate the influence of potential source regions via LRAT. Organochlorine pesticides (OCPs, mainly comprising DDTs, HCHs, and HCB), polychlorinated biphenyls (PCBs, mainly comprising penta- and hexa-CBs), and polycyclic aromatic hydrocarbons (PAHs, mainly comprising three- and four-ring) were detected at low concentrations of 40–1000, <MDL–88, and 2100–34,000 pg/g, respectively. We elucidated three major geographical distribution patterns of POPs, which were influenced by (1) the distribution of total organic carbon and black carbon in soil, (2) historical use of pesticides in the Tarim Basin, and (3) continuous emissions. Central Asia and the Tarim Basin were major potential source regions of POPs reaching the eastern Pamirs via LRAT. Historical use of technical HCH or lindane and technical DDT in potential source regions may contribute to the accumulation of HCHs and DDTs in the eastern Pamirs, respectively. Local sources seem to play a more important role in the occurrence of PAHs in the study area. By being under the control of less contaminated westerly air flow, the eastern Pamirs are more pristine than the core of the Tibetan Plateau where the Indian and East Asia monsoons deliver contaminants from highly industrialized areas in East China and India.

Polycyclic aromatic hydrocarbons in urban and rural residential soils, levels, composition profiles, source identification and health risk &amp; hazard

The presence of PAHs in soil and the close proximity of soils to humans may lead to human exposure through various pathways. Therefore, levels of priority sixteen PAHs in soils were measured for human and environmental health risk assessments. No recent study on human and environmental health effects due to PAHs in soils is available for Delhi. The levels of total PAHs in soils ranged between 213–851 μg kg−1 with the mean of 550 ± 55 μg kg−1, which was comparatively lower in rural area. Seven carcinogenic PAHs (7CPAHs) accounted for 28.6% of ∑16PAHs. However, benzo(a)pyrene toxicity equivalency (BaPTE) of 7CPAHs accounted for 98.2% to ∑BaPTE. Lifetime average daily dose (LADD) of PAHs through soil for human adults and children was 9.43 × 10−8 mg kg−1 d−1 and 3.53 × 10−7 mg kg−1 d−1, respectively. The estimated incremental lifetime cancer risk (ILCR) for children (4.80 × 10−5) was comparatively higher than adults (1.29 × 10−5). The index of additive cancer risk (IACR), potential threat to potable groundwater water quality from leaching of carcinogenic PAHs from soil were also estimated and presented. The observed levels of PAHs in soils and their human health risk and environmental health hazard at different locations were assessed using recommended guidelines.

Indoor and Outdoor PM10-Bound PAHs in an Urban Environment. Similarity of Mixtures and Source Attribution.

Given that the European Union lays down air quality objectives associated with outdoor environments, indoor air mixtures' study acquires a remarkable relevance. This work aims to submit a stepwise methodological framework for assessing similarities between indoor and outdoor air mixtures and apportioning potential emission sources. For reaching this goal, PM10 particles were systematically and simultaneously collected at an indoor (dominant emission sources free) and outdoor environment during a year to determine the PAH content in both air mixtures. Broadly, outdoor PAHs levels were higher than at the indoor location, supporting a strong association between both mixtures (r = 0.968, p > 0.001), mainly during the cold period (r = 0.896, p > 0.001). The light molecular weight PAHs were highlighted at the indoor site, in particular to naphthalene and anthracene. Outdoor emission sources influenced the indoor PAH levels, especially high and medium molecular weight PAHs. The local-traffic load was identified as a dominant pollution source responsible for more than half PAHs determined at both environments. Therefore, the control of outdoor emission sources would be translated into an improvement of indoor air quality.

PAH and PCB body-burdens in epibenthic deep-sea invertebrates from the northern Gulf of Mexico

There is a paucity of information on the levels of PAHs and PCBs in the deep-sea (≥200 m). In this study, the body-burdens of 16 PAHs and 29 PCBs were measured in: Actinaria (sea anemones), Holothuroidea (sea cucumber), Pennatulacea (sea pens), and Crinoidea (sea lilies) in the deep Gulf of Mexico. All epibenthic species were collected at depths of approximately 2000 m. The PAH and PCB congener profile displayed a similar pattern of bioaccumulation across all four taxa. The high molecular weight PAH, dibenz[a,h]anthracene, was the most abundant PAH in all organisms, ranging from 36 to 53% of sum total PAHs. PCBs 101 and 138 exhibited the highest levels at 20–25% of total congener concentrations in all taxa. The exposure to PAHs and PCBs is likely attributed to contaminated particulate organic matter that is consumed by the deposit and filter feeding epibenthic megafauna sampled in this study.

Determination of PAHs Concentration in Some Types of Phoenix Dactylifera L. Samples from Al-Diwaniyah Markets by Using Soxhlet and Gas Chromatography-Mass Spectroscopy Technique

The concentration of poly aromatic hydrocarbons in three types of Phoenix Dactylifera L fruits (Iraqi, Iranian, Saudi) which are all collected from Iraq-Al-Diwaniyah city have been investigated. The PAHs levels in our samples were estimation by using Gas Chromatography Mass Spectroscopy (GC-MS). The technique of GC-MS was used for determination of ten of prior sixteen of carcinogenic PAHs compounds that are globally approved. The data indicated that thereare four PAHs in Iraqi dates, where fluorene was the highest level of these compounds with concentration of 124.509 μg/mL followed by Acenaphthylene, Naphththalene, andAnthracene with concentration about 16.227 μg/mL, 15.850 μg/mL, and 3.035 μg/mL respectively. While the Saudi dates found that there are five types of PAHs with different concentrations, where the highest concentration is for Naphththalene with concentration about 269.491 μg/mL followed by Acenaphthylene, Phenanthrene, Anthracene and Pyrene with levels of 23.670 μg/mL, 8.340 μg/mL, 1.761μg/mL and 0.543 μg/mL respectively.

Variations of Polycyclic Aromatic Hydrocarbons in Vegetable Oils During Seed Roasting Pre-Treatment

Seed roasting is a critical step for fragrant oil as it achieves the development of aroma and flavor, but also it is the way of polycyclic aromatic hydrocarbons and other harmful substances generated. In this study, for the purpose of mimic moderate roasting as well as powerful roasting condition, five oilseeds (peanut, sesame, sunflower, rapeseed and flaxseed) were submitted to roast at six selected temperatures (160 °C, 180 °C, 200 °C, 220 °C, 240 °C and 260 °C) for increasing time. The PAH levels in the five oils which obtained from corresponding roasted seed were quantified via GC-MS. The results showed that the concentrations and types of PAH substances in oils rapidly became more plentiful over seed roasting temperature and time, resulting an increase in total PAH concentrations, particular at temperature above 200 °C. The PAHs produced during the roasting of oilseeds may be mainly attributed to the lipid content and the degree of unsaturation (or P/S index) of the oilseeds. The higher lipid content in the oilseed, the easier it is to produce PAHs during seed roasting pretreatment. Oilseed with high polyunsaturated fatty acids tend to produce HPAH, on the contrary, low polyunsaturated fatty acids tend to produce LPAH.

The content and distribution of trace elements and polycyclic aromatic hydrocarbons in soils of Maritime Antarctica.

Antarctica is considered as one of the most pristine areas on Earth. However, increasing intensity of human presence on the sixth continent (scientific operations, functioning of the numerous scientific stations, tourism activities) makes it crucial to investigate the level of environmental pollution within the vulnerable ecosystem of Antarctica. Soils play a significant role in processes of accumulation, mobilization, redistribution of chemical elements within landscapes, and ecosystems. The aim of this work was to analyze the levels of 17 polycyclic aromatic hydrocarbons and eight trace elements in soils of King George and Ardley islands, Western Antarctica. Moreover, our work was aimed to determine the trends and reasons of anthropogenic pollution of Antarctic soils and characterization of accumulation levels of trace elements and PAHs. Results showed the predominance of light PAHs in all studied sites. The content of benzo(a)pyrene does not exceed the threshold concentration (adopted by different national environmental legislation systems). At the same time, the content of benzo(a)pyrene, which is a marker of anthropogenic contamination, is relatively low or equal to 0 in soils of reference landscapes. Cu and Zn were found as most abundant elements in all studied soils. The highest lead concentration content has been described in soil from Bellingshausen station. In general term, obtained Igeo values for trace elements in all samples were under or slightly above the 0 level, indicating low to moderate pollution of the studied soils. This study also contributes new data on trace element accumulation in soils strongly influenced by ornithogenic factor. Principal component analysis allowed to estimate the probable sources of specific trace metals and their relationship with soil variables. Ornithogenic factor has been also revealed as a driver for some trace element accumulation especially in breeding penguin colonies. High contents of organic matter in ornithogenic habitats could increase trace metal mobility, environmental risks for surrounding terrestrial environments should be considered.

Quantitative Assessment of Human Health Risks Based on Soil Heavy Metals and PAHs Sources:Take a Polluted Industrial Site of Beijing As an Example

In this study, 130 surface soil samples were collected at an industrial pollution site in Beijing and the contents of As, Be, Cd, Cu, Cr, Hg, Ni, Pb, Sb, Ti, Zn, and 16 PAHs were determined. The positive matrix factorization (PMF) model was used to analyze the sources of heavy metals and PAHs, and the contributions of these sources to carcinogenic risk and hazard index in the study area were calculated. The results showed that the contents of Cd, Cu, Pb, Hg, As, Zn, and Cr in the soil exceeded the background values in different degrees; Cd, Hg, Pb, Zn, and Cu exceeded the background values by>50%. Low molecular weight PAHs (two and three rings) and high molecular weight PAHs (four to six rings) accounted for 39.6% and 60.4% of the total content of 16 PAHs. The PAH content at 77% of the sampling points at the target site was more than 1000 μg ·kg-1, which suggests severe PAH pollution at the site. Heavy metals Be, Ti, As, and Ni mainly originated from natural sources. There are three major sources of 7 heavy metals and 16 PAHs at the site: coal combustion (Hg and ∑16PAHs), smelting (Cu, Cr, Pb, and Zn), and traffic (Sb and Cd). The contribution rates of these sources to the total average contents of seven heavy metals and sixteen PAHs at 130 sampling sites were 8.46% (coal combustion), 90.61% (smelting), and 0.94% (traffic). Human health risk assessment results showed that the carcinogenic risk of seven heavy metals and ∑16PAHs ranged from 4.17×10-6 to 39.38×10-4, and the hazard index ranged from 0 to 32.23. The maximum carcinogenic risk and hazard index values were calculated near the coking plant. Benzo[α]pyrene was the PAH that posed the highest carcinogenic risk and Zn was the heavy metal that had the highest hazard index value. The average carcinogenic risk of coal combustion was 2.16×10-4, accounting for 50.26% of the total average carcinogenic risk. The average hazard index of smelting was 0.834, accounting for 56.43% of the total average non-carcinogenic risk. These two pollution sources are responsible for the high levels of heavy metals and PAHs in the soil of the steel smelting sites that pose the most severe health risks. The results of this study can provide reference for soil remediation and process optimization at other heavily polluted industrial sites.