Status of PAHs in Environmental Compartments of South Africa: A Country Report

This article covers the status of PAH concentrations and composition patterns in surface water, air, sediment, and soil samples from South Africa. Despite South Africa being one of the largest economies in Africa, it is only recently that researchers have reported the presence and possible sources of these compounds in various environmental compartments. This article discusses the potential hotspots and possible sources of these compounds. It also compares the total PAH concentrations and percentage composition patterns of the individual PAHs. So far, total concentrations of five PAHs determined in sediment samples from the Johannesburg area, Gauteng Province, gave the highest concentrations ranging from 1233–136,276 μg kg^?1. The total concentration of six PAHs found in runoff water from the Venda region of the Limpopo Province, gave the highest concentration with a range of 28.7–3192.6 μg L^?1. The decreasing order of percentage composition of PAHs in water samples tended to follow 3-ring > 4-ring > 2-ring PAHs. In soil samples the decreasing order of percentage composition followed 4-ring > 3-ring > 5-ring > 2-ring > 6-ring PAHs. The total freely dissolved PAHs followed solubility of the compounds with 2-ring > 3-ring > 4-ring > 5-ring > 6-ring PAHs. Some of the identified sources of PAHs using molecular ratios include petrogenic emissions such as from petroleum combustion from vehicles and pyrolytic sources such as coal combustion by coal powered power stations, as well as iron and steel production industries. Oil spills were also identified as major PAH contributor in runoff water from the Venda region of the Limpopo Province.     

Emission of Polycyclic Aromatic Hydrocarbons (PAH) from Solid Waste Incinerator Equipped with an After-Combustion Chamber

Abstract

Polycyclic aromatic hydrocarbons (PAH) are typical indicators of incomplete combustion during solid waste incineration. The PAH emissions caused by waste incineration vary according to waste composition and operating parameters such as furnace temperature, after-combustion conditions, excess air, carbon monoxide levels.

In this work, the content of PAH in the fly ashes (sampled upstream the flue gas treatment system) and bottom ashes produced by the combustion of a refuse derived fuel (RDF) in a rotary kiln incinerator equipped with an after-combustion chamber is determined. The emission levels of PAH are correlated with different operating conditions of the incinerator to evaluate the destruction efficiency of the after-combustion chamber for these compounds.     

Characterization of PM2.5-Bound Polycyclic Aromatic Hydrocarbons in the Ambient Air of Győr,Hungary

ABSTRACT

In Hungary, the nationwide monitoring of PM10-bound polycyclic aromatic hydrocarbons (PAHs) in ambient air is great importance for a number of reasons related to human health, the environment and compliance with European Union legislation. However, the measurement of PAH concentrations in PM2.5 aerosol fraction has not been carried out. Therefore, the concentration, distribution and sources of PM2.5-bound PAHs at different urban sites of Gy?r were investigated in a heating season. The total PAH concentrations (sum of 19 individual PAH compounds) ranged from 1.32 to 37.27 ng/m³ with the mean value of 10.54 ng/m³. The high molecular weight PAHs with 5 and 6 aromatic rings were the most abundant PAHs in PM2.5 aerosol samples, which averaged 82% of total PAHs. Using benzo(a)pyrene (BaP) equivalent approach on the concentration data of carcinogenic PAH species, BaP and indeno(1,2,3-cd)pyrene contributed the highest carcinogenic exposure equivalent (1.25 and 0.19 ng/m³ on average). However, the incremental lifetime cancer risk (ILCR) values for resident children and adults indicated low-potential cancer risk (ILCR < 10^?6). The source apportionment results reflected that the major sources of PAH compounds in the Gy?r atmosphere were fossil fuel combustion and vehicle emissions.     

NEWLY IDENTIFIED PRODUCTS OF BENZENE DROPLET COMBUSTION: POLYCYCLIC AROMATIC HYDROCARBONS OF THREE TO TEN RINGS

Abstract

In order to investigate further the polycyclic aromatic hydrocarbons (PAH) produced by benzene droplet combustion, we have obtained and analyzed a highly-concentrated benzene droplet combustion sample, using high pressure liquid chromatography (HPLC) with diode-array ultraviolet-visible (UV) absorbance spectroscopy. In addition to benzo[k]fluoranthene, we have identified ten large (5- to 10-ring) PAH never before reported as products of benzene pyrolysis or combustion: dibenz[a,c]anthracene, indeno[1,2,3-cd]fluoranthene, anthanthrene, cyclopenta[cd]benzo[ghi]perylene, coronene, dibenzo[a,i]pyrene, cyclopenta[bc]coronene, benzo[a]coronene, naphtho[8,1,2-abc]coronene, and ovalene. In this sample we have also identified three smaller PAH, benz[f]indene, 2-ethynylanthracene, and benzo[c]phenanthrene, never before reported as products of benzene pyrolysis or combustion. In order to document the unequivocal identification of these compounds as benzene droplet combustion products, we present the UV absorbance spectrum of each newly identified benzene product, along with the matching UV spectrum of the respective PAH reference standard. Several of the identifications have required the acquisition of specially synthesized reference standards. Combined with our previous results, the present findings show that 50 individual PAH (and related compounds), of up to 10 rings in size, are produced during benzene droplet combustion.     

Distribution and Sources of Polycyclic Aromatic Hydrocarbons (PAHs) in Surface Sediments from the Northern Part of the Persian Gulf (Hormuzgan Province)

Sediments from the intertidal areas of Hormuzgan province in northern part of Persian Gulf (Iran) were investigated for the levels and possible sources of 15 polycyclic aromatic hydrocarbons (PAHs). Samples of sediments were collected from twelve sampling sites and analyzed for PAHs by gas chromatography–mass spectrometry (GC-MS). The results showed that the total concentrations of PAHs ranged from 765 to 1898 ng/g dry weight. Composition pattern in the sediment samples from 12 sampling sites was dominated by 4-ring PAH compounds. Molecular indices based on ratios of PAH concentrations were used to differentiate PAHs from pyrolitic, petrogenic and mixed origins. The results of study suggested that the main sources of PAHs in the sediment were mixed with pyrolitic and petrogenic inputs. According to the US sediments quality guidelines (SQGs) (ERL/ERM) sediments of the mentioned region did not show any ecotoxicological risk for benthic organisms.     

Sources and Health Risk of Organic Compounds in Respirable Particles in Tehran,Iran

Forty-one respirable particle (PM₄) samples were collected from October 2011 through March 2012. This timespan covered the fall and winter seasons in Tehran, Iran. The associated polycyclic aromatic hydrocarbon (PAH) and n-alkane concentrations were analyzed to investigate the sources of these compounds and health risks of the former. The average total PAH and n-alkane concentrations were 16.2 ng/m³ and 758 ng/m³, respectively. The most abundant PAHs were 2- and 3-ring compounds, while the most abundant n-alkanes were nC₁₆ and nC₁₈. The results of source identification by factor analysis (FA) are consistent with and complementary to those from diagnostic ratios (DRs). The PAH DRs indicate a dominant contribution from pyrogenic sources, in particular diesel engines from local traffic sources, while FA reveals a diesel-fuelled vehicle emission related factor, a gasoline engine emission-related factor, an industrial source factor and a wood combustion, incineration and tire tread source factor. The n-alkane DRs indicate dominant contributions from anthropogenic sources or vehicular emissions, while FA reveals a fossil fuel combustion factor and a biogenic source factor. Although the average BaP concentration was below the Iran Department of Environment's annual average standard of 1 ng/m³, the BaP-equivalent concentration of the PAHs (BaP_PEQ) indicates harmful effects cannot be ruled out. The ICR_L and ICR_U data suggests a potential cancer risk incidence of about 1–54 individuals per million in the population from a lifetime of 70 years inhalation of particle associated PAHs in Tehran. These findings highlight the importance of reducing emissions from traffic, in particular emissions from diesel-fuelled vehicles, in Tehran.     

PHYSICO-CHEMICAL ARTEFACTS IN ATMOSPHERIC PAH DENUDER SAMPLING

Two annular diffusion denuder-filter samplers were operated concurrently to assess sampling artefacts arising from possible breakthrough of gas-phase PAH, blow-off of particle-bound PAH and degradation due to atmospheric ozone. The results of a field investigation held at Montelibretti (Rome, Italy) indicate that such artefacts are minimized or avoided when 6 h air samples are collected at 6 L min^?1 and an ozone scrubbing denuder is placed at the beginning of the sampling train. The partitioning of semi-volatile PAH followed closely that previously observed in downtown Rome but their absolute concentrations were up to an order of magnitude lower.     

LEAVES OF NERIUM OLEANDER L. AS BIOACCUMULATORS OF POLYCYCLIC AROMATIC HYDROCARBONS (PAH) IN THE AIR OF PALERMO (ITALY): EXTRACTION AND GC-MS ANALYSIS,DISTRIBUTION AND SOURCES

Polycyclic Aromatic Hydrocarbons (PAH) were determined in the leaves of Nerium oleander L. an evergreen plant that occurs widely in both urban and rural areas, to monitor the degree of pollution in the urban area of Palermo (Italy) compared to remote areas. Twenty sites (urban roadside, urban, urban park, suburban and rural) in and around Palermo city were investigated.

The purpose of this research was to investigate concentration levels and distribution patterns and relate them to possible sources. Analysis of 19 PAH was performed by gas chromatography/mass spectrometry (GCMS) using selected ion monitoring (SIM). The total amount of PAH ranged from 10 to 166 μg/Kg d.w.

Each source gives rise to a characteristic PAH pattern, and it is therefore possible to get access to the processes that generate the compounds. To this aim, the recommended as priority pollutants by the Environmental Protection Agency (EPA), perylene and three additional alkylated compounds were analyzed.

Positive correlations were found between total PAH content of the leaves with CO, benzene and particulate levels measured in air of Palermo.     

An assessment of human influences on fluxes of nitrogen from the terrestrial landscape to the estuaries and continental shelves of the North Atlantic Ocean

Our analysis for the International SCOPE Nitrogen Project shows that the fluxes of nitrogen in rivers to the coast of the North Atlantic Ocean vary markedly among regions, with the lowest fluxes found in northern Canada (76 kg N km^–2 yr^–1) and the highest fluxes found in the watersheds of the North Sea (1450 kg N km^–2 yr^–1). Non-point sources of nitrogen dominate the flux in all regions. The flux of nitrogen from the various regions surrounding the North Atlantic is correlated (r ² = 0.73) with human-controlled inputs of nitrogen to the regions (defined as net inputs of nitrogen in food, nitrogen fertilizer, nitrogen fixation by agricultural crops, and atmospheric deposition of oxidized nitrogen), and human activity has clearly increased these nitrogen flows in rivers. On average, only 20% of the human-controlled inputs of nitrogen to a region are exported to the ocean in riverine flows; the majority (80%) of these regional nitrogen inputs is stored in the landscape or denitrified. Of all the nitrogen inputs to regions, atmospheric deposition of NO_y is the best predictor of riverine export of nitrogen from non-point sources (r ² = 0.81). Atmospheric deposition of this oxidized nitrogen, most of which derives from fossil-fuel combustion, may be more mobile in the landscape than are regional inputs of nitrogen from fertilizer, nitrogen fixation in agriculture, and nitrogen in foods and feedstocks. Agricultural sources of nitrogen, although larger total inputs to most temperate regions surrounding the North Atlantic Ocean, appear to be more tightly held in the landscape. Deposition of ammonium from the atmosphere appears to be a very good surrogate measure of the leakiness of nitrogen from agricultural sources to surface waters. This suggests a management approach for controlling surplus nitrogen used in agricultural systems. The sum of NO_y and ammonium deposition proves to be an amazingly powerful predictor of nitrogen fluxes from non-point sources to the coastal North Atlantic Ocean for temperate-zone regions (r ² = 0.92; p = 0.001). By comparing fluxes with some estimates of what occurs in watersheds with minimal human impact, it appears that human activity has increased riverine nitrogen inputs to the ocean by some 11-fold in the North Sea region, by 6-fold for all of Europe, and by 3-fold for all of North America. These increased flows of nitrogen have clearly led to severe eutrophication in many estuaries, and have probably contributed to some eutrophication on the continental shelf in the North Sea and in the Gulf of Mexico. In other regions, however, the input of nitrogen to continental shelves is dominated by cross-shelf advection from deep-Atlantic waters, and the increased inputs from rivers are relatively minor.     

Source characterization and the environmental impact of urban street dusts from Egypt based on hydrocarbon distributions

The aliphatic and aromatic fractions of the extracts of ten street dust (SD) samples collected from eight cities covering a wide geographic area of Egypt were analyzed using gas chromatography with flame ionization detector (GC-FID) and GC-MS to compare their hydrocarbon distributions. To identify their sources, the extracts of the possible source materials were also analyzed. The impact of SDs on the marine environment was investigated in a marine sediment collected from the Western Harbor of Alexandria. The GC-FID profiles of the aliphatic fractions showed considerable differences in the n-alkane distribution that permits the classification of the SDs into five groups. This grouping reflects the environments of the cities in which they are collected. The carbon preference index and the unresolved complex mixture relative to the total resolved peaks values revealed that automobile exhaust is the main source of the hydrocarbons in these SDs with a significant contribution from terrestrial higher plant waxes to group 1 (Nile Delta cities). The sterane and hopane profiles supported this conclusion. The total polycyclic aromatic hydrocarbon (PAH) concentrations ranged from 27 to 379 ng/g (dry wt.) and showed clear differences between the SDs. The lowest and highest concentrations were found in samples from Shebeen and Port Said, respectively. The PAH distribution patterns and the ratio of the sum of combustion specific PAHs to total PAHs in samples from Alexandria, Port Said and Cairo were similar, implying similar sources. PAH ratios indicated a mixture of pyrogenic and petrogenic sources of PAHs in all samples where asphalt and automobile fuel exhaust were the major contributors of PAHs in Alexandria, Port Said, Cairo and Sharm El Sheikh cities. These ratios also indicated the predominance of diesel-operated vehicles to the PAHs signatures of Alexandria, Port Said and Cairo while gasoline emissions influence more strongly the PAH distributions in the SDs from Shebeen, Kafr El Sheikh and Sharkea. The PAH fingerprints excluded fresh oil and tire particles as major contributors. Both SDs and petrogenic sources significantly contributed to the hydrocarbon signature of the marine sediment from the Western Harbor of Alexandria.     

PAH Profiles of Charbroiled Hamburgers: Pyrene/B[a]P Ratios and Presence of Reactive PAH

Abstract

Analysis of the polycyclic aromatic hydrocarbons (PAH) in charbroiled hamburgers, used in an earlier study of BaP-DNA adducts in peripheral white blood cells, has been accomplished using HPLC with UV diode array detection. The concentration data for one of these PAH, benzo[a]pyrene (BaP), are in excellent agreement with data obtained using a thin-layer chromatography (TLC)/fluorescence technique. There is significant interest in pyrene/BaP ratios in these samples and other sources of human exposure to PAH since urinary metabolites of both compounds have been used as biomarkers of exposure. In the food samples examined, this ratio is roughly 5. However, differences in cooking procedures between different studies suggest that this value can only be used semi-quantitatively. The BaP concentrations themselves vary by a factor of almost twenty in hamburgers prepared under very similar conditions. Some unstable PAH, including cyclopenteno[cd]pyrene and methylated PAH are found in the hamburger. This possibly reflects their decreased reactivity under conditions different from those which prevail in the outdoor atmosphere.     

PAH and other emissions from burning of JP-8 and diesel fuels in diffusion flames

Jet fuel JP-8 is of technical interest to the military aviation industry. JP-8 is now the single battlefield fuel for all US Army and Air Force equipment, replacing gasoline altogether and gradually replacing diesel fuel. Hence, emissions from the combustion of this fuel are the subject for this investigation. The emissions from the combustion of JP-8 fuel are examined and are compared to those from diesel fuel No. 2, burned under identical conditions. Combustion occurred inside a laboratory furnace in sooty diffusion flames, under adverse conditions that typically emit large amounts of products of incomplete combustion (PIC). Under such conditions, even compounds that otherwise might appear only in trace amounts were present in sufficient quantities for detection. The study reports on emissions of CO, light volatile organic compounds, semi-volatile organic compounds with an emphasis on polycyclic aromatic hydrocarbons (PAH), particulate emissions, oxides of nitrogen (NO_x) and oxides of sulfur (SO₂). Some PAH compounds are suspected of posing a threat to human health, benzo[a]pyrene being listed as a bio-accumulative toxin by the EPA. An afterburner was also used to examine the effects of longer furnace residence time. Results have demonstrated that PAH emissions from the combustion of diesel fuel were higher than those of JP-8, under most conditions examined. Moreover, as the temperature of the primary furnace was increased, in the range of 600–1000 °C, most of the emissions from both fuels increased. Particulate emissions were reduced by the afterburner, which was operated at 1000 °C, only when the primary furnace was operated at the lowest temperature (600 °C), but that condition increased the CO emissions. Overall, transient combustion of these two fuels, burning in laminar and sooty diffusion flames, did not reveal major differences in the emissions of the following PIC: C1–C4 light aliphatic hydrocarbons, PAH, CO and particulate matter.     

Distribution,Sources, and Risk of Polycyclic Aromatic Hydrocarbons in the Core Sediments from Baiyangdian Lake,China

The burial characteristics and risks of 16 polycyclic aromatic hydrocarbons (PAHs) in core sediments from Baiyangdian Lake were investigated through gas-chromato graphy/mass spectrometry. The total concentrations of the 16 PAHs ranged from 39.48–1877.75 ng g^?1. The low-molecular-weight PAHs (two- to three-ring PAHs) were the dominant species, contributing 40.10–92.18% to the total PAHs, with a mean of 71.01%. Based on the observed molecular indices and on principal component analysis, the PAHs inputs were initially dominated by biomass and coal combustion, and atmospheric deposition and surface runoff could be the major transport pathways. The contaminated source characteristics, hydrodynamic condition, and sediment textural composition are the key factors affecting the distribution and source of PAHs. By conducting a risk quotient analysis between specific PAH concentrations and their corresponding sediment quality values, the top layer sediments were found to have a potential biological impact and relatively high toxicity. However, such impact should have no impairment. The toxic potency of PAHs in Baiyangdian Lake could be described by using the toxic equivalent of benzo[a]pyrene.     

Use of the Semipermeable Membrane Device (Spmd) to Sample Polycyclic Aromatic Hydrocarbon Pollution In A Lotic System

Abstract

Relative concentrations of aqueous polycyclic aromatic hydrocarbons (PAH) were investigated in an urban creek. Samples were obtained at five sites within a 600-m segment of the creek that is critical habitat for an endangered species of fish. the sampling technique entailed immersion of semipermeable membrane devices (SPMDs) in the water for intervals as long as 64 d. SPMDs are passive, in situ, mtegrative samplers of bioavailable (truly dissolved) PAH and other hydrophobic organic contaminants. Two point sources of PAH to the 600-m segment of the creek were differentiated. Aqueous concentrations were found to wane dramatically over the relatively short section of the creek between the point sources. All samples were almost devoid of alkyl-substituted PAH, indicating that the ultimate sources were probably of pyrogenic nature.     

THE LOADS OF PAHS IN WASTEWATER AND SEWAGE SLUDGE OF MUNICIPAL TREATMENT PLANT

Abstract

Sewage and sewage sludge from a municipal wastewater treatment plant were analyzed for 16 EPA-PAHs. This plant is a classic mechanical-biological treatment plant, consisting of activated sludge technology with additional chemical treatment for the removal of phosphorus compounds. The process of sewage sludge treatment is carried out in closed as well as open sludge digesters. Primary and mechanically thickened sludge are passed through the fermentation process. Digested sludge is dewatered on filter-press through addition of flocculent. The measurements were obtained to investigate the effect of different treatment stages on PAH content in wastewater and sewage sludge. The following wastewater samples were collected: crude ones and those after sand trap, primary sedimentation, biological treatment and secondary sedimentation. Sewage sludge samples were collected from: primary sludge, digested sludge and dewatered sludge. PAH load in influent, mechanically and biologically treated sewage, as well as in raw digested and dewatered sludge, were calculated. PAHs were extracted from wastewater and sludge samples, with cyclohexane, dichloromethane using an ultrasonic method. Gas chromatograph equipped with mass spectrometry was used for qualitative and quantitative determination of PAHs. Mechanical and biological treatment proved the removal of 83–85% of PAHs from the influent. Despite this its daily PAH load introduced into the environment was high and reached 27–37% of PAH load in influent. In sewage sludge it was 46–70 g/d of PAHs (carcinogenic PAHs content 4–12%). In waste sludge (filter pressed sludge and sand from detrirer) PAH total load reached 42–68 g/d with (10–17% of carcinogenic PAHs).     

Relative Genotoxicities of PAH of Molecular Weight 252 AMU in Coal Tar-Contaminated Sediment

Bioassay-directed chemical fractionation methodology was used to calculate relative mutagenic potencies of polycyclic aromatic hydrocarbons (PAH) of molecular weight 252 amu in coal tarcontaminated sediment from Sydney Harbour, Nova Scotia. A normal phase HPLC technique was used to separate organic solvent extracts into fractions containing isomeric PAH of a single benzologue class. Bioassays with Salmonella typhimurium strain YG1025 with the addition of oxidative metabolism (S9) showed that approximately 50% of the mutagenic activity observed in the sediment extract was associated with PAH of molecular weight 252 amu. Further separation of the 252 PAH fraction using reversed phase HPLC yielded subfractions containing individual compounds; bioassay dose-response curves for these subfractions showed that benzo[a]pyrene was responsible for approximately 75% of the activity of the 252 PAH fraction.     

Polycyclic aromatic hydrocarbons emitted by power stations,and influence of combustion conditions

Polycyclic aromatic hydrocarbons (PAH) were measured in the emissions of seven power stations. For the first time, all measurements were made with standard sampling and uniform analysis procedures. The influence of effective power of the station, nature of fuel (coal, oil, diesel oil) and kind of furnace was determined. The relations between PAH emission and excess oxygen in flue gas, NO_x concentration, calorific value and composition of the fuel and amount of ash were established. Very fast reactions, at high temperature, between PAH and gaseous pollutants are possible in the furnace or during the passage of flue gas through the stack. The gas-particle ratio of the PAH also depends on all combustion parameters. The PAH emitted are unburnt matter, numerous light compounds (with two or three rings) or heavy compounds or after demethylation of alkyl PAH. The impact of power stations on the amount of PAH in the atmosphere cannot exceed 5% in large cities.     

Particle Associated Polycyclic Aromatic Hydrocarbons (PAHS) in Urban Air of Agra

Total Suspended Particulate Matter (TSPM) samples were collected at Nunhai Agra from April to September 2006. The concentrations of 16 PAHs in aerosols were quantified. The dominated predominant PAHs in TSPM include high molecular weight (HMW) congeners BghiP, DbA, IP and BaP. Nap and Acy were not detected in any of the samples. The sum of 14 priority PAHs ranged from 150 to 480 ng m^?3 with a mean value of 269 ± 121 ng m^?3. The Results indicated that PAH concentrations at Nunhai were higher than in other industrial sites, but are comparable to those measured in several urban Chinese cities, however, and less than the industrial locations of China. Higher HMW PAH concentration were attributable to higher rates of emissions as well as or greater scavenging and adsorption of vapor phase PAH on available TSPM. Potential sources of PAHs in aerosols were identified using the diagnostic ratios between PAHs. Vehicular emissions were the main contributors of particulate-associated PAHs, with minor contribution from stationary combustion sources may also contribute to the particulate PAHs. PAHs in aerosols were predominantly from gasoline and diesel engines.     

Detection of Polycyclic Aromatic Hydrocarbons (PAHs) in Human Breast Milk

Abstract

Exposure to polycyclic aromatic hydrocarbons can result from numerous sources including dietary as well as environmental. Exposure to polycyclic aromatic hydrocarbons has been well-established through combustion sources, particularly coal-fired power plants, automobile and diesel exhaust emissions, and the burning of fossil fuels. In addition, exposure to polycyclic aromatic hydrocarbons occurs through the intake of tobacco smoke, both mainstream and sidestream, and this exposure potentially represents one of the highest concentrations of polycyclic aromatic hydrocarbons to which we can be exposed. The plethora of chemicals found in tobacco presents considerable problems when trying to assess biological exposures to single or multiple compounds since the interactions of each of the chemicals with each other may deter the detection of the previous compound. In addition other materials found in tobacco may mask selective detection of certain compounds thereby minimizing their quantitative and qualitative analysis in biological products exposed to tobacco.

Previous studies from our laboratory have focused on the detection and characterization of biological markers to aromatic hydrocarbons, particularly in the application of protein biomarkers. In addition, our research has focused on the characterization of biomarkers of tobacco related products during specific time frames of pregnancy ranging from early first trimester pregnancies to third trimester and delivery samples. In the present series of investigations, we investigated the application and utilization of breast milk as a biological marker of postdelivery exposure of neonates to polycyclic aromatic hydrocarbons.     

DETERMINATION OF POLYCYCLIC AROMATIC HYDROCARBONS (PAHs) IN SEDIMENTS AND BENTHOS COLLECTED ON THE COAST OF CHIBA

Eight polycyclic aromatic hydrocarbons (PAHs) including benzo[a]pyrene were analyzed in sediment and benthos collected on the coast of Chiba Prefecture in Japan by gas chromatography-mass spectrometry (GC/MS). The total concentration of the PAHs ranged from 8 to 18 μ g/kg-dry in the sediments and from 36 to 59 μ g/kg-wet in the benthos, Mactra quadrangularis, Scoletoma nipponica, and Arenicola basiliensis. The PAH composition in the sediments and the benthos was similar at four sampling points and dominated by phenanthrene (Phe), fluoranthene (Flu), and pyrene (Pyr). The ratios of abundance of Flu to that of Pyr, Flu/Pyr, and of Phe/anthracene suggest that the PAHs in the benthos are derived from the combustion of fossil fuels. The ratio, R, of the PAH concentration in the benthos to that in the sediment is 2.0 for Scoletoma nipponica and 1.8 for Arenicola basiliensis in average, indicating that the bioaccumulation is not significant in the benthos. However, the R value for perylene in Scoletoma nipponica was 3.7 times as large as the average.