Deposition Fluxes Of Polycyclic Aromatic Hydrocarbons Research Articles

諏訪湖における多環芳香族炭化水素類の年間収支の推定

In the present study, we estimated inflow and effluent load of Polycyclic Aromatic Hydrocarbons (PAHs) in Lake Suwa, Japan. Estimation of PAHs inflow and effluent load were performed by measuring changes in stream flow and concentration of suspended solids (SS) in the lake and river water. Results showed that the concentration of SS increased with stream flow. Annual (March 2004 to February 2005) inflow and effluent load of SS at the lake were calculated as 8.9×106 kg and 7.6×106 kg, respectively. The mass balance between inflow and effluent load indicated that 1.3×106 kg of SS were sedimentated to the lake. The total amount of Σ9PAHs (Phenanthrene, Pyrene, Chrysene, Benzo[e]pyrene, Benzo[b]fluoranthene, Benzo[k]fluoranthene, Benzo[a]pyrene, Dibenz[a,h]anthracene, Benzo[ghi]perylene) in lake SS varied by 230±120 g/lake (average±SD); the maximum amount exceeded 500 g/lake, which was observed in May and October 2004. Specifically, for Benzo[a]pyrene the total amount in lake SS was 14±7 g/lake. Estimation of total Σ9PAHs flowing into Lake Suwa and out through Kamaguchi Gate indicated Σ9PAHs values of 8.6 and 3.5 kg/yr, respectively. The mass balance between Σ9PAHs inflow and outflow indicated that approximately 5.1 kg/yr of Σ9PAHs were sedimentated with SS to the lake. The annual flux of PAHs in Lake Suwa calculated in the present study agreed with the deposition flux of PAHs in a previous study estimated from sediment cores (4 kg/yr) (Ikenaka et al.: Environ. Pollut., 138, 530-538 (2005)). Inflow loads of PAHs markedly increased in May 21, October 9, and October 21 when heavy rains occurred, occupying approximately 27 % of the annual inflow. These results indicated that large quantities of PAHs flowed into the lake when river flow increased by heavy rain.

Atmospheric Deposition and Marine Sedimentation Fluxes of Polycyclic Aromatic Hydrocarbons in the Eastern Mediterranean Basin

Atmospheric input was studied and found to be the major source of PAHs in the eastern Mediterranean open marine ecosystem. Dry and wet atmospheric deposition, air-sea exchange, and sediment trap fluxes of polycyclic aromatic hydrocarbons (PAHs) in the eastern Mediterranean basin were estimated from November 2000 to July 2002. Seven dry and four wet deposition samples were analyzed in total and PAH concentrations were determined. Airsea exchange fluxes based on air-water concentration gradientwere drawn from five air and water samples collected concurrently from a coastal area in the eastern Mediterranean. Total annual average deposition fluxes of dry, wet, and air-sea exchange sigma35PAHs were 58.0, 165.7, and -706.4 microg m(-2) y(-1), respectively. Only 1.1 and 0.7% of the total atmospheric deposition flux of PAHs was measured in the sediment traps at 280 and 1440 m depth, respectively.

마산과 행암 지역으로 유입되는 다환방향족탄화수소(PAHs)의 대기 침적 플럭스 산정과 특성

Atmospheric bulk (wet and dry) samples were monthly collected in Masan and Heangam areas of Korea, to assess the deposition flux and seasonal variation of polycyclic aromatic hydrocarbons (PAHs). Deposition fluxes of PAHs in bulk samples were determined using gas chromatography coupled to mass spectrometer detector (GC/MSD). Particle deposition fluxes from Masan and Haengam areas varied from 13 to <TEX>$87\;g/m^2/year$</TEX> and from 5 to <TEX>$52\;g/m^2/year$</TEX>, respectively. PAHs deposition fluxes in atmospheric bulk samples in Masan and Haengam areas ranged from 135 to <TEX>$464\;{\mu}g/m^2/year$</TEX> and from 62.2 to <TEX>$194\;{\mu}g/m^2/year$</TEX>, respectively. Atmospheric deposition fluxes of particles and PAHs in this study were comparable to or slightly lower values than those from different locations in Korea and other countries. PAHs profiles of atmospheric deposition bulk samples showed slightly different from two sampling areas, however the predominant species of PAHs were similar. Indeno (1,2,3-c,d)pyrene, benzo(g,h,i)perylene, phenanthrene compounds were the most detected PAHs in deposition bulk samples. Carcinogenic PAHs occupied the contribution of approximately <TEX>$30-40\%$</TEX> of the total PAHs deposition fluxes. The non-metric multi-dimensional scaling (MDS) was used, to assess the differentiation of PAHs source between two sampling areas. The result suggests that PAHs contamination sources were different according to the location and season surveyed. There was no an apparent relationship between the PAHs deposition flux against temperature and rainfall amount, even though summer season with the highest temperature and the largest amount of precipitation showed the lowest PAHs deposition flux. Benzo(e)pyrene/benzo(a)pyrene ratio indicated that the photo-degradation process was one of important factors to the seasonal variation of PAHs with the lower deposition fluxes.

Temporal and spatial variations of the particle size distribution of PAHs and their dry deposition fluxes in Korea

The atmospheric particle size distributions between 0.1 and 100 μm in diameter and their dry deposition fluxes of polycyclic aromatic hydrocarbons (PAHs) were measured at four sites in the mid-part of Korea to characterize the spatial distribution, the PAHs levels and dry deposition. Samples were collected at Inchon, Seoul, Yangsuri, and Yangpyoung between 21 and 25 February, and between 12 and 16 May 2000. Ambient size distributions were measured with a cascade impactor and a coarse particles rotary impactor. Dry deposition fluxes of particles were measured with dry deposition plates. The total particulate PAHs concentrations are between 22.9 and 410 ng m −3 , with an average of 139 ng m −3 . The total particulate PAHs dry deposition fluxes were between 10 and 24 μg m −2 day −1 in winter, and between 4.1 and 8.2 μg m −2 day −1 in spring. Both the ambient concentrations and dry deposition fluxes of PAHs in winter are higher than spring mainly due to higher fuel consumption. The ambient concentrations of PAHs in Inchon were the highest followed by Yangpyoung, Yangsuri, and Seoul. The PAHs concentrations and fluxes of Yangsuri and Yangpyoung, rural areas in Korea, are higher than the rural areas in USA. It suggests a serious PAHs pollution level of rural areas in Korea. Based on the PAHs individual compounds’ levels and size distributions, it was suggested that Yangpyoung and Yangsuri have local PAHs sources in addition to transport from urban areas.

Polycyclic aromatic hydrocarbons in the bulk precipitation and surface waters of Northern Greece

Bulk (wet and dry) precipitation and surface water sampling was undertaken in the main plain of central Macedonia in Northern Greece. Fourteen polycyclic aromatic hydrocarbons (PAHs) included in the US EPA's priority pollutant list were analysed. The concentrations determined in bulk precipitation were in general within the range of values worldwide reported. Concentrations were highest in the cold months. Deposition fluxes of PAHs were of the same order of magnitude as reported data. The greatest values were found when high concentrations of PAHs in precipitation coincided with large precipitation amounts. The concentrations of PAHs in surface waters (main rivers, tributaries, ditches, etc) were in general lower than those in bulk precipitation, and among the lowest reported for European rivers, excepting Np and Ph. Bulk deposition and domestic effluents are suggested as being the main PAH sources into surface waters.

Polychlorinated biphenyl and polycyclic aromatic hydrocarbon deposition to and exchange at the air–water interface of Esthwaite Water, a small lake in Cumbria, UK

Atmospheric concentrations and deposition fluxes of several polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) were measured concurrently over a 1-year period at a shore-based site at Esthwaite Water, to estimate their loadings from the atmosphere to the lake water surface. The PAH deposition fluxes (μg m −2 month −1) to conventional upturned Frisbees varied from 0.19 (anthracene) to 7.8 (phenanthrene), with a ΣPAH deposition of 33.5. Phenanthrene, fluoranthene and pyrene contributed >50% of the ΣPAH deposited. The deposition fluxes of PCBs ranged from 0.03 (octa-PCBs) to 0.38 (tri-PCBs) μg m −2 month −1 with a ΣPCB flux estimated at 0.87 μg m −2 month −1. The coefficients of variation of deposition varied from 75% (octa-PCBs) to 120% (tri-PCBs) and from 90 to 150% for individual PAHs. Temporal variability in fluxes to the collector was large, suggesting highly variable atmospheric concentrations and scavenging processes. Atmospheric PAH concentrations were negatively correlated with temperature over the sampling period, suggesting that the source function—rather than temperature-dependent, air–surface equilibrium partitioning—primarily controlled air concentrations. Deposition fluxes of PAHs correlated well with rainfall between January and September, suggesting that particle washout was the main factor controlling deposition over this period. The controlling factor for deposition between October and December was related to the increased source function of the compounds to the atmosphere. Regression analysis of the data for PAHs with ≥4 rings gave a strong positive correlation between the deposition flux and atmospheric concentrations, suggesting that the transfer of compounds occurred with a similar efficiency. Simultaneous air and water sampling over an annual cycle was used to calculate fugacity quotients for individual PAHs and PCBs. These calculations showed that PCBs were outgassing from the lake water throughout the year (i.e. volatilisation>deposition) whilst PAH transfers varied seasonally with net deposition in winter months when there is no ice cover, and net volatilisation at all other times.

Atmospheric inputs of selected polycyclic aromatic hydrocarbons and polychlorinated biphenyls to southern Chesapeake Bay

Atmospheric and precipitation levels of polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) were measured at a rural site in southern Chesapeake Bay throughout 1991. Wet depositional inputs of PAHs and PCBs to the lower Bay were directly determined from the data; dry deposition and gas exchange fluxes were also estimated for PAHs. Notable seasonal variability in the atmospheric concentrations of aerosol-associated PAHs and gaseous PCBs was observed. Conversely, wet deposition concentrations and fluxes exhibited little temporal variability. Annual wet deposition fluxes of PAHs and PCBs were determined to vary spatially in Chesapeake Bay, presumably due to the influence of temperature on the efficiency of washout. The uncertainty in measured wet deposition and ambient atmospheric concentrations is 25–50%, however, there is currently large uncertainty associated with estimates of dry deposition and gas exchange fluxes of semivolatile organic contaminants (SOCs). Nonetheless, atmospheric fluxes of SOCs are predicted to be both into and out of lower Chesapeake Bay.