Petrogenic Sources Research Articles

Spatio-temporal distribution, source apportionment, ecological and human health risks assessment of polycyclic aromatic hydrocarbons in Sombreiro River Estuary, Niger Delta, Nigeria

ABSTRACT The spatio-temporal distribution, source apportionment, and risks of polycyclic aromatic hydrocarbon (PAHs) were investigated in the Sombreiro River Estuary, Niger Delta, Nigeria. Water, sediment and oysters were obtained from the estuary and analyzed for 16 priority PAHs using gas chromatograph coupled with mass selective detector after extraction. The levels of the ∑16-PAHs in the water, sediment and oyster ranged from 25-10079 µg/L, 495-12811 µg/kg and 489-10823 µg/kg respectively for all locations and seasons. The results showed significant spatio-temporal variations in PAHs concentrations in all the matrices. The ecological risk assessment revealed high risk posed by the PAHs level to the estuarine ecosystem. The health risk indicated unacceptable carcinogenic risk to human via ingestion of oysters. Besides, for water and sediments, both ingestion and dermal pathways indicated unacceptable cancer risk. Source apportionment suggested that the PAHs in the estuary were from both pyrogenic and petrogenic sources.

Assessment of persistent and emerging pollutants levels in marine bivalves in the Gulf of Suez, Egypt

Bivalves possess important ecological and economic values. They have been extensively used as bioindicators for both emerging and classical pollutants in the aquatic environment. This study investigates the levels of trace metals, polycyclic aromatic hydrocarbons (PAHs), and organochlorine pesticides (OCPs), alongside microplastic (MPs), in Tridacna maxima, Paphia textile, and Paratapes undulatus, collected from the Gulf of Suez. This work represents the first investigation of MPs in marine bivalves from the Gulf of Suez. MPs were detected in 72% of the specimens examined and four types of MPs were identified. The metal pollution index indicated that bivalves may have long-term toxic effects on human consumers. The results showed minimal hydrocarbon pollution. Diagnostic ratios indicated a combination of pyrolytic and petrogenic sources, with a notable influence from pyrolytic origins. The risk assessment reflected that the levels of certain trace metals, PAHs, and OCP contaminants could present a low risk to human health.

Seasonal dynamics of polycyclic aromatic hydrocarbons in microplankton from Kaohsiung Harbor (Taiwan Strait, northeastern South China Sea)

The impact of polycyclic aromatic hydrocarbons (PAHs) on the marine food web is crucially understudied in the primary trophic system. We evaluated the seasonal dynamics of PAHs in microplankton in a polluted environment (Taiwan), northeastern South China Sea. Replicate size-fractionated microplankton (55–1000 μm) were freeze-dried, and PAHs were extracted with a 1:1 v/v ratio of acetone: n-hexane, then analyzed using GC–MS. Total PAHs ranged between 68 and 2548 ng/g dw in microplankton, greatest during spring (130–2548 ng/g), followed by autumn (135–772 ng/g) and summer (44–423 ng/g). Spatial distribution varied through seasons but was higher in the southern part (S6 > S4 > S5 > S2 > S3 > S1 > S7), dominated by higher-ring PAHs from mixed pyrogenic and petrogenic sources. PAHs are significantly correlated with environmental factors, especially in colder seasons and lower salinity areas. Suspended matter and plankton influenced PAH transport and partitioning seasonally. Plankton's PAHs seasonal changes and environmental influences are revealed in an anthropic environment.

Concentration and Distribution of Specific Siloxanes (D5 and D6) and PAHs in the Anacostia and Potomac Rivers, USA

The waterways adjacent to Washington DC, USA have a history of contamination from heavy metals, nutrients, pesticides, and industrial chemicals. Among the chemicals of concern are PAHs, which are a historical contaminant but also have modern pyrogenic and petrogenic sources in the area’s waterways. Another group of contaminants that are of emerging interest are siloxanes (silicones), which are widely used as lubricants, sealants, and cosmetics. Some lower-molecular-weight siloxanes are regulated by the EU in recognition of harm to aquatic life, but there are no restrictions in the United States. In fact, studies examining water pollutants do not typically test for siloxanes. Here, we present the concentrations of specific PAHs and siloxanes from surface sediments in the Potomac and Anacostia Rivers (including the Anacostia’s tributaries) collected between 2018 and 2023. Both D5 (decamethylcyclopentasiloxane) and D6 (dodecamethylcyclohexasiloxane) were found in most locations, with concentrations averaging 0.13 and 0.006 mg/g (dry mass), respectively. Pyrene, fluoranthene, bibenzyl, and phenanthrene were also found in the Anacostia and some of its tributaries, with concentrations increasing downstream. In the Potomac, concentrations were generally lower than those observed in the Anacostia. Based on ratios of pyrene to fluoranthene + pyrene, the likely source of PAHs was petrogenic.

Polycyclic aromatic hydrocarbons (PAHs) in fish (Clarias gariepinus) of southwestern rivers, Nigeria: Occurrence, distribution, and potential human exposure risks

This study was undertaken to analyze Polycyclic aromatic hydrocarbons (PAHs) in fish (Clarias gariepinus) from six major rivers within southwest Nigeria to assess the ecotoxicological and human health risks. The average concentrations of total PAH (∑PAH) ranged from 12.18 to 49.12 µg/g and from 10.35 to 38.09 µg/g during the dry and wet seasons, respectively, and the ranges were significantly higher than the prescribed WHO (0.001 µg/g) and European Union (0.002 µg/g) recommended safe levels for human consumption. The low molecular weight PAHs (2–3 rings) dominated the profile, suggesting petrogenic sources. Phenanthrene remains the highest contributor to PAH intake across all locations and seasons. The toxicity equivalent quotients (TEQ), which represents the sum of B(a)P equivalent concentration [B(a)Peq] ranged from 0.851 to 2.014 μg BaP/g with a slightly higher range of 1.046–2.763 μg BaP/g during the dry and wet seasons, respectively. Across both seasons, the estimated hazard quotient (HQ) and hazard index (HI) were found to be < 1, suggesting consumption of Clarias gariepinus has no non-carcinogenic risks. The estimated excess cancer risk value (1.55×10−2 to 5.03×10−2) from consumption of C gariepinus exceeded all regulatory guideline values for potential cancer risk. The excess cancer risk, predominated by B(a,h)A (0.0194 µg/g) and B(a)P (0.0163 µg/g) suggests a greater risk of exposure during the wet season. The study showed no human health risk due to PAHs in Clarias gariepinus obtained from southwestern rivers in Nigeria. However, due to bioaccumulation, policies that will ensure regular monitoring of PAHs in seafood are recommended to maintain a sustainable ecosystem.

Source identification of polycyclic aromatic hydrocarbons (PAHs) in soils around crude oil contaminated area in Ohaji/Egbema, Imo State

ABSTRACT This study aims to determine the source of polycyclic aromatic hydrocarbons (PAHs) in the soils surrounding an area in Ohaji/Egbema, Imo State, that has been contaminated by crude oil. Soil samples were collected in the study area using a soil auger at a depth of 0–20 cm at three sampling locations (sample A, sample B, and sample C) in the Mmahu community in Ohaji/Egbema. In each of the sampling locations, twenty sub-samples were collected from twenty sampling points and pooled together to form representative samples for each of the sampling locations. Prior to GC-MS analysis, the composite samples were air-dried, sieved through a 2-mm mesh, and then kept in pet bottles that had been previously cleaned. The GC-MS investigations were carried out using a Shimadzu Model 2010 GC-MS (Shimadzu, Japan) fitted with an HP-5 MS fused silica column. This was used to quantify the 16 USEPA priority PAHs in the studied soils. The sum of the 16 USEPA priority PAHs in the sample locations ranged from 0.0192 mg/kg in the control sample to 10.73 mg/kg in sample A. Compared to high molecular weight PAHs (4–6 rings), the total concentration of low molecular weight PAHs (2–3 rings) was found to be substantially greater. According to the PAH molecular diagnostic ratio, all sampling points had low to high molecular mass ratios >1, which suggests that the origin of the PAH contamination was petrogenic. The petrogenic source of contamination was attributed to oil spillage around the study area. The knowledge of source identification of PAHs in soils helps in the determination of the most appropriate remediation strategy in order to prevent further contamination and minimise the risks to human health and the environment.

Pesticides and polycyclic aromatic hydrocarbons in honey and Apis mellifera from the Yucatán Peninsula, Mexico

Beekeeping in the Yucatán Peninsula is generally practiced in rural zones and is important for honey production in Mexico. Our aim was to determine organochlorines (OCPs), organophosphates (OPs), glyphosate, imidacloprid pesticides and polycyclic aromatic hydrocarbons (PAHs) residues in honeybee A. mellifera and honey of apiaries from the Yucatán Peninsula, that represents a potential risk to consumers and is related to massive honeybee mortality. During 2021; first sampling (S1) was performed in the honey harvest season and the second sampling (S2) after the honey harvest season. In A. mellifera was detected highest concentration of ∑OCPs (6370.470 ng/g) and ∑PAHs (169.292 ng/g) in Oxkutzcab, Yucatan during S2; glyphosate (166.649 ng/g) in Xkuncheil, Campeche and imidacloprid (63.878 ng/g) in Xbec, Yucatán during S1. We did not detect OPs. In honey was detected highest concentration of ∑OCPs (25.6 ng/g) in Celestún, Yucatan and ∑OPs (3.893 ng/g) in China, Campeche during S1; glyphosate (233.611 ng/g) in Abalá, Yucatán and imidacloprid (11.882 ng/g) in Luis Echeverría, Quintana Roo during S2. Total found 19 samples with PAHs of petrogenic sources and 29 samples with pyrogenic sources. Glyphosate, imidacloprid, ∑DDTs, Chlorpyrifos, Methoxychlors and ∑HMW-PAHs showed temporal and spatial patterns.

Distribution, levels, sources and risk assessment of polycyclic aromatic hydrocarbons in the bottom sediments of a Mediterranean river under multiple anthropopressures (Soummam River), Algeria

The Soummam River, a vital watercourse in Algeria is threatened by anthropogenic activities despite its protected wetland status. This study is the first to assess sediment pollution in the Soummam River, examining levels, compositions, sources of 16 PAHs and their effects on the environment and human health. Analysis employing Principal Component Analysis (PCA) and molecular diagnostic ratios pointed to petrogenic sources, likely stemming from petroleum leaks originating from aging pipeline and vehicles, as well as pyrogenic sources arising from vehicle exhaust and biomass combustion. Environmental and health risks were assessed through risk quotients (RQ), Sediments Quality Guidelines (SQG) and Total Lifetime Cancer Risk (TLCR). Ecological risk was found to range from moderate to high, with anticipated biological impacts, while cancer risk was deemed low. Toxicity assessment, measured by TEQ, revealed that the majority of monitoring stations exceeded safe levels. Consequently, urgent action by local authorities is warranted to implement ecosystem rehabilitation measures.

Analysis and Assessment of Contamination Degree and Emission Sources of Polycyclic Aromatic Hydrocarbons (PAHs and Me-PAHs) in Surface Sediments from Central Coast of Vietnam

Polycyclic aromatic hydrocarbons (PAHs) and their derivatives are a diverse group of organic pollutants, which are relatively persistent and toxic. Simultaneous determination of unsubstituted PAHs and methylated PAHs (Me-PAHs) is necessary to provide comprehensive insights into contamination levels and sources of these pollutants. In this study, we collected surface sediment samples in Vietnamese central coast to analyze 7 PAHs and 12 Me-PAHs. The sediment samples were extracted by using a focused ultrasonic processor with acetone/hexane (1:1) mixture and toluene. The extract was purified by column chromatography technique with activated silica gel and dichloromethane/hexane (1:3) as elution solvent. PAHs and Me-PAHs were determined by a gas chromatography/mass spectrometry (GC/MS) system operated in electron impact ionization (EI) and selected ion monitoring mode (SIM). Concentrations of total 7 PAHs and 12 Me-PAHs ranged from 30 to 246 (average 92) nanograms per gram sediment (ng/g). These levels were comparable to or lower than those measured in Vietnamese river sediments and marine sediments from some other countries in the world. The accumulation profiles of PAHs and Me-PAHs indicated that their emissions are likely associated with mixed pyrogenic and petrogenic sources. Our results have provided preliminary information about the pollution degree and accumulation characteristics of these substances in Vietnamese marine environments. Additional comprehensive studies should be performed to characterize contamination characterisrics, emission sources, and ecological risks of PAHs and their derivatives in this country.

Health risk of heavy metals and PAHs contaminants in goat meat de-haired with waste tyres and plastic in Calabar, Nigeria

Dehairing goat meat during processing using waste car tyres and plastic is a potential route of contaminants, hence the purpose of the study. Goat meat (muscle) samples (n = 50) collected from 3 abattoirs in Calabar, Nigeria, were analysed for heavy metals and poly aromatic hydrocarbon (PAH). The mean heavy metals in goat meat were: 0.20 ± 0.02 (Pb), 0.57 ± 0.06 (Cr), 4.31 ± 0.18 (Cd), 5.02 ± 0.54 (Ni), and 0.02 ± 0.01 (Co) mg/kg, with total PAH levels of 65.91 ng/g. The mean Cr, Cd, and Ni (mg/kg) in the meat were higher than the World Health Organization/Food and Agricultural Organization (WHO/FAO) acceptable limits for food. The dominant PAH was benzo (a) anthracene. Diagnostic ratios and PCA revealed pyrogenic and petrogenic sources as contributors of the PAHs in goat meat. The carcinogenic risk of Cr, Cd, Ni, anthracene, benzo (a) anthracene, and indeno [1, 2, 3, cd] pyrene in adults and children were greater than 10−4, indicating risk. Ni and benzo (a) anthracene were the most ingested contaminants and main carcinogenic sources in adults and children. Given the impending chronic health risks in the practice, there is a need for safer processing methods that do not further contaminant the meat.

Sourcing aliphatic and polycyclic aromatic hydrocarbons (PAHs) in Jinga shrimp (Metapenaeus affinis) muscle tissues and surface sediments (study case: Northwest Persian Gulf).

This study addresses the sources of aliphatic hydrocarbons (AHs) and polycyclic aromatic hydrocarbons (PAHs) in the surface sediments of the northwestern Persian Gulf and the muscle tissues of Jinga shrimp (Metapenaeus affinis), a commercially important aquatic species. In November 2018, 28 Jinga shrimp samples were systematically collected from four key fishing areas in Behrgan and Khormusi: Imam Khomeini Port (S1), Mahshahr Port (S2), Sejafi (S3), and Behrgan Wharf (S4). Additionally, sediment samples were collected from these locations, and AHs and PAHs concentrations were analyzed using gas chromatography-mass spectrometry (GC-MS). The average aliphatic concentration in Jinga shrimp was 4800.32 (μg g-1 DW), exceeding the sediment samples' 2496.69 (μg g-1 DW) estimate. Hydrocarbon component analysis revealed EPA priority list (PAH-16) and measured PAHs (PAH-29) concentrations in Jinga shrimp ranging from 1095.8 to 2698.3 (ng g-1 DW) and in sediments from 653.6 to 1019.5 (ng g-1 DW). Elevated AHs and PAHs in Jinga shrimp, compared to sediments, suggest a petrogenic source, notably at station S4 near Behrgansar and Nowruz oil fields. Low molecular weight (LMW) compounds dominated in both shrimp and sediment PAHs. Aliphatic composition profiles in shrimps closely mirrored sediment profiles, illustrating an even-to-odd carbon dominance gradient. Diagnostic ratio examinations of hydrocarbons indicated pervasive petroleum derivatives in the environment. This study establishes a direct correlation between hydrocarbon concentrations in shrimp and sediment samples and the corresponding aliphatic groups, PAH-16, and PAH-29. The findings underscore the potential of Jinga shrimp as a reliable indicator of hydrocarbon pollution in the northwestern Persian Gulf.

Characterization of polycyclic aromatic hydrocarbons in mangrove sediments from Ifiekporo Creek, Warri, Nigeria

The occurrence and level of polycyclic aromatic hydrocarbons (PAHs) in mangrove sediment from Ifiekporo Creek in Warri, Delta State, Nigeria, were assessed in this study. The extraction of PAHs from the sediment samples was achieved using the PAH analytical test method (USEPA 8270). This method measures the individual concentrations of extractable PAHs in samples. The PAHs were quantified within the C11-C22 subgroup. The basic GC parameters for the analysis of polyaromatic hydrocarbons were analysed using a gas chromatography‒mass selective detector (GC‒MSD). The individual PAH concentrations in the mangrove sediment samples ranged from 850 µg/kg−1 to 3470 µg/kg−1. PAH source apportionment employing isomeric ratios and multivariate statistics indicated both pyrogenic and petrogenic source inputs in the sediment samples. The order of PAH homology in the sediment was 3-ring > 2-ring > 4-ring. The sediment samples were mostly dominated by LMW PAHs. The results of the ecological risk assessment in the study area indicate that there is low ecological risk associated with PAH exposure in sediment. These results provide data on the concentrations and compositional patterns of PAHs, which is useful for understanding the effects, sources, fates, and transport of PAHs in sediment in the study area, as well as for providing relevant information for environmental quality management and forensic studies.

Potential of Pinus eldarica Medw. tree bark for biomonitoring polycyclic aromatic hydrocarbons in ambient air

Urban trees' biomonitoring of pollutants such as polycyclic aromatic hydrocarbons (PAHs) yields pertinent and useful data for air pollution management. The aim of this study was to biomonitor PAHs in pine (Pinus eldarica Medw.) trees in the city of Isfahan and identify their sources. In total, 34 samples of outer bark of the trees were collected and their contents of 16 EPA PAHs were analyzed. With a median value of 136.3 ng/g, the total PAH contents in tree barks varied from 53.4 to 705.2 ng/g. The average values of the diagnostic ratios for Ant/(Ant + Phe), Flu/(Flu + Py), BaA/(BaA + Chr) and IP/(IP + BP) were 0.19, 0.49, 0.45 and 0.49, respectively, revealing the PAHs majority source of pyrogenic. Meanwhile, principal component analysis showed two major types of PAHs sources including pyrogenic (fossil fuel combustion and industrial activities) and petrogenic (uncombusted) sources. The average ratio An/(An + Phe) and Flu/(Flu + Py) in bark samples was close to their relevant ratios in ambient air which demonstrated the potential use of this approach for biomonitoring of PAHs.

Sources of hydrocarbons and their risk assessment in seawater and sediment samples collected from the Nile Delta coast of the Mediterranean Sea

The aim of this work is to examine the levels, distribution, bases, and hazards of n-alkanes (n-C9 to n-C20) and PAHs in the seawater and sediments around oil production locations in the whole delta region. The variations in the levels of PAHs and n-alkanes in seawater and sediment of the Nile delta coast of the Mediterranean were investigated using GC–MS/MS. The Σn-alkanes residues ranged between 12.05 and 93.51 mg/L (mean: 50.45 ± 17.49 mg/L) and 4.70 to 84.03 µg/g (mean: 31.02 ± 27.995 µg/g) in seawater and sediments, respectively. Total PAHs concentrations ranged between 4.485 and 16.337 μg/L (average: 9.47 ± 3.69 μg/L) and 1.32 to 28.38 ng/g (average 8.61 ± 7.57 ng/g) in seawater and sediment samples, respectively. The CPI (carbon preference index) values fluctuated between 0.62 and 1.72 (seawater) and from 0.234 to 2.175 (sediment), proposing the variation sources of n-alkane in the studied area. PAHs concentrations were lower than the Effective Range Low (ERL) and Effective Range Median (ERM) levels. The Toxic Equivalent Quotient (TEQ) values oscillated between 0.002 and 6.84 ng/L and from 3.72 to 13.48 ng/g for the seawater and sediment samples, respectively. The Ant/(Ant + Phe) ratio in sediment and seawater samples indicated a pyrolytic source while the BaA/(BaA + Chry) ratio indicates petrogenic sources in most of the studied stations.

Source Apportionment and Health Risk of Some Organic Contaminants in Water and Suspended Particulate Matter from Imo River, Nigeria

The objective of this study was to provide the source identification and assessment of potential health associated with some organic contaminant detected in water and suspended particle matter (SPM) from the Imo River, Nigeria using gas chromatography with a flame ionization detector (GC/FID) after 1:1 ratio solvent mixture (n-hexane and dichloromethane) extraction. The findings on SPM revealed the values; pH (5.42±0.097-5.567±0.057), conductivity (74.58±5.390-87.6±0.9 uS/cm), and total organic carbon (TOC) (3.626±0.366-6.143±0.176), and surface water; pH (6.077±0.049-6.46±0.52), conductivity (49.03±1.430- 58.12±0.553 uS/cm). The total concentrations of both low and high molecular PAHs in SPM recorded at stations1-3 were 4.384 mg/kg, 16.87 mg/kg, and (22.69 mg/kg); surface water 2.329 mg/L, 7.428 mg/L and 6.657 mg/L. The source apportionment of PAHs in SPM and surface water via molecular diagnostic ratios identified both petrogenic source (crude oil, petroleum spillages, and seepages) and pyrogenic sources (combustion of grass, wood, coal, and gas flaring). A further analysis with Principal Component Analysis (PCA) revealed two principal components, with 65.568% for component 1 and 34.432% for component 2 for SPM, and 62.80% for principal components and 37.2% for principal component 2 for surface water. The correlation analysis of PAHs affirmed common sources such as petrogenic and pyrogenic origins. The toxic equivalent factor of total benzo(a)pyrene for 6 ∑PAHs in SPM was recorded as 3.693 mg/kg, 1.605 mg/kg, and 0.453 mg/kg; surface water was recorded as 0.823 mg/L, 1.858 mg/L, and 0.353 mg/L, while the mutagenic equivalency quantities of SPM were recorded as 3.693mg/kg, 1.146 mg/kg, and 0.316 mg/kg; surface water 0.739 mg/L, 0.938, and 0.577 for stations 1-3. The effect of carcinogenic PAHs in SPM was higher in adults than in children, with regards to ILCR analysis. Users of Imo Rivers should be guided on the exposure of SPM and surface water since the toxic, mutagenic, and cancer risk levels of the river are above the permissible limit in some stations.

History of organic pollution in montane lake Issyk-Kul, Kyrgyzstan, Central Asia, inferred from a sediment core

In arid regions, montane lakes are valuable water sources and play important ecological roles. However, recent human-induced inputs of organic pollutants are threatening lake ecology in such regions and becoming a matter of great concern. To investigate pollutant histories and sources, we measured polycyclic aromatic hydrocarbons (PAHs) and n-alkanes in a dated sediment core that spans the last ∼350 years, from montane Lake Issyk-Kul (Kyrgyzstan, Central Asia). Results showed that organic pollutants were delivered to Lake Issyk-Kul in four stages and that their concentrations increased from Stage I (∼1670–1800 CE) to Stage IV (∼2000–2010 CE). Furthermore, we tracked the sources of sedimented PAHs using their ratios combined with n-alkanes data. Ratios of PAHs Ant/(Ant + Phe), Flt/(Flt + Pyr) and Bap/BghiP indicated that inputs during Stage II (∼1800–1970 CE) and Stage III (∼1970–2000 CE) came mainly from high-temperature combustion of coal and vehicle emissions. PAHs in Stage I and Stage IV, however, were mainly derived from low-temperature combustion and petrogenic sources. Diagnostic PAH ratios, combined with the natural n-alkane ratio (NAR＜0) and unresolved complex mixtures (UCM), showed that the sources of PAHs in Stage I were mainly from erosion of bedrock and partly influenced by forest wildfires, different from the source during Stage IV, which was mainly from refined petroleum caused by accidental spills. Our assessment of the contamination history of the lake indicates that toxicity risk to the waterbody from sediment PAHs is low, but recent discharges arising from traffic deserve attention.

Concentration of Polycyclic Aromatic Hydrocarbons in Water from Hand-dug Wells in Some Communities in Ekpeyeland, Rivers State, Nigeria

Well water sources from selected communities in Ekpeyeland were assessed for the concentrations of polycyclic aromatic hydrocarbons (PAHs). The assessment was conducted seasonally in six communities. The concentrations of the PAHs were determined using standard methods and procedures and finally quantified by the use of GC-MS chromatography. The result showed the presence of all the 16 USEPA priority PAHs in the examined water samples. Seasonal variations were not significant. The summed values of PAHs from stations and seasons were above the permissible limit required for by WHO. Classification of the different categories of PAHs identified higher molecular weight (HMW) PAHs more in concentration than lower molecular weight (LMW) PAHs in the wells. Source identification proved that both pyrogenic and petrogenic sources were responsible for the presence of PAHs in the well water. However, pyrogenic source was the more prominent source of PAHs in the water. There was high level of carcinogenic PAHs in the water and thus the water portends danger to the users. Therefore, the locals are advised not to consume the water to avoid its effect on the long run.

Origins and health risk assessment of PAHs/APAHs/NPAHs/OPAHs in PM2.5 at a background site in North China Plain: Implications for crude oil emissions

In order to investigate the origins and health impact of PAHs/APAHs/NPAHs/OPAHs in PM2.5 at North China Plain (NCP) under the influence of Shengli oil field, PM2.5 samples were collected in winter, spring, summer and autumn from 2018 to 2019 at a background site in NCP, and 19 PAHs, 5 APAHs, 7 NPAHs, and 6 OPAHs were analyzed. The mean level of PAHs, APAHs, NPAHs, OPAHs were 9.13 ± 11.03, 1.33 ± 1.45, 0.23 ± 0.72, 0.48 ± 0.48 ng/m3, respectively. APAHs were the most abundant derivatives of PAHs, which indicated crude oil was an important source. Further, ratios of 1-MN/NAP showed that APAHs emitted from crude oil were relatively fresh. Significant correlations were found among PAHs and APAHs with similar rings. The positive matrix factorization model demonstrated that secondary formation (9.32%), oil industry emissions (32.68%), emissions from steel and vehicles (18.12%), biomass and coal emissions (30.00%), as well as petrogenic sources (9.88%) were the main sources of PAHs/APAHs/NPAHs/OPAHs. Through the analysis of concentration weighted trajectories, it was discovered that the southwestern region of Dongying was the primary potential source of the oil industry, while the Bohai Bay and Shandong coastal area was the primary source region for petrogenic sources. ILCR results indicated that it was highest in winter; adults (30–70 years) were people who had the highest cancer risks.

Evaluation of Sources of Polycyclic Aromatic Hydrocarbons in Thermally Treated Meat and Fish: A Food Pollutant Study

This study assessed the sources of PAH in cooked meat and fish. Gas Chromatography-Mass Spectrometry (GC-MS) performed the sample analysis. The total PAH concentrations (mg/kg) ranged from 0.911 to 2.763. Levels of low-molecular-weight (LMW) PAHs varied from 0.353 mg/kg to 1.786 mg/kg, while high-molecular-weight (HMW) PAHs ranged from 0.516 to 0.977 mg/kg. The study detected 2 to 6-ring PAHs, the 3-ring PAHs were the most prominent. PAHs diagnostic ratios, their plots and principal component analysis (PCA) were used to assess the origin of PAHs in the samples. Values of diagnostic ratios, such as Phenanthrene/Anthracene (1.84–3.58), Anthracene/(Anthracene + Phenanthrene) (0.21–0.35), Fluoranthene/Pyrene (0.00-1.79), Fluoranthene /(Fluoranthene + Pyrene) (0.00-0.64), Indeno[123-cd-]pyrene/(Indeno[123-cd-]pyrene + Benzo[ghi]perylene) (0.00–43), LMW-PAH/HMW-PAH (0.59–1.83) and Benzo[a]pyrene/(Benzo[a]pyrene + Chrysene) (0.00–0.50) indicated that the PAHs in the samples were from mixed sources, with greater contributions from pyrogenic sources. They show that the barbecued samples were contaminated primarily by pyrogenic PAHs (biomass (wood/charcoal) burning, liquid fuel combustion, or automobile exhaust emissions). The grilled and smoked samples were mostly contaminated from different combustion sources (traffic and non-traffic, biomass burning, automobile exhaust and liquid fuel), with little input from petrogenic sources. The combination plots of the ratios also show that PAH was from mixed sources (petrogenic and pyrogenic), but mostly from a pyrogenic source (wood/charcoal burning, liquid fuel combustion, and automobile exhaust emissions) with minor inputs from petrogenic origin, as shown by the value of LMW-PAH/HMW-PAH ratios &gt; 1 in a few samples. PCA equally showed that four factors accounted for 82.47% of the total variability and separated the PAHs into identifiable source groups, comprising mixed sources, combustion of liquid fossil fuel, automobile/diesel engine exhaust, gasoline and oil combustion and biomass burning. The study showed that contamination from the natural habitats of the animals contributed to the PAHs in them in addition to the cooking process. This therefore underscored the impacts of anthropogenic pyrogenic activities on PAHs formation and levels in meat and fish, hence adequate control/reduction of these activities will promote a healthier and safer food environment for all.

Source Apportionment of Polycyclic Aromatic Hydrocarbons in Indoor Fine Dusts from Residential and Public Buildings in Port Harcourt, Rivers State, Nigeria

The sources of polycyclic aromatic hydrocarbons in indoor fine dust from residential and public buildings in Port Harcourt, Rivers State, Nigeria was investigated using source apportionment tools such as diagnostic/isomeric ratios, principal component analysis (PCA) and hierarchical cluster analysis (HCA). A total of twenty-seven indoor fine dusts comprising of twenty samples from residential building and seven samples from public buildings were collected from Port Harcourt. The PAHs in the dust samples were quantified by gas chromatograph equipped with mass spectrometry (GC-MS) after extraction by ultra-sonication with hexane/dichloromethane/acetone and cleaned up on a silica gel/alumina column. The Σ16 PAH concentrations in the indoor fine dusts ranged from 3136 µg kg-1 to 44332 µg kg-1 for residential buildings and 2580 µg kg-1 to 15372 µg kg-1 for public buildings. The results of source apportionment indicated that the PAHs in the indoor fine dusts were from mixed sources pyrogenic sources (coal, wood, petroleum, biomass, and fossil fuel combustion) and petrogenic sources with significant contribution from pyrogenic sources.