Polycyclic Aromatic Hydrocarbons Concentrations In Sediments Research Articles

Sediment Porewater Partitioning of Polycyclic Aromatic Hydrocarbons in Three Cores from Boston Harbor, Massachusetts

Polycyclic aromatic hydrocarbon (PAH) concentrations were measured in sediments and porewaters isolated from three cores from Boston Harbor, MA. Measured porewater PAH concentrations were significantly lower than the concentrations predicted by two- and three-phase equilibrium partitioning models. We hypothesize that only a fraction of the measured sediment PAH concentrations was available to partition rapidly into sediment porewaters.

Comparative bioaccumulation of polycyclic aromatic hydrocarbons from sediment by two infaunal invertebrates

MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsTheme Sections MEPS 123:107-124 (1995) - doi:10.3354/meps123107 Comparative bioaccumulation of polycyclic aromatic hydrocarbons from sediment by two infaunal invertebrates Meador JP, Casillas E, Sloan CA, Varanasi U Bioaccumulation of polycyclic aromatic hydrocarbons (PAHs) from field-contaminated sediments by 2 infaunal invertebrates, Rhepoxynius abronius (a non-deposit feeding amphipod) and Armandia brevis (a non-selective, deposit-feeding polychaete), was examined. Sediments were selected over a large geographical area of the Hudson-Raritan estuary (New York, USA) to assess the potential for bioaccumulation from a typical urban estuary. Assessment of bioaccumulation in these invertebrates is important because of the need to understand their health and role in ecosystem functioning and because they are vectors of sediment-associated contaminants to demersal fish. Our study compared the response of these 2 species over a wide range of PAH concentrations to learn how feeding mode may affect contaminant accumulation. After 10 d of exposure to sediments, we assessed the tissue concentrations of 24 PAHs and found no significant differences for the low molecular weight PAHs (LPAHs) between R. abronius and A. brevis. There was, however, a large differential observed between species for bioaccumulated high molecular weight PAHs (HPAHs). Because we assumed that the amphipod was not feeding and most of its tissue burden was received through ventilation of interstitial water (IW), we concluded that IW was probably the major route of uptake for the LPAHs for both species and that sediment ingestion was a much more important uptake route of HPAHs for the polychaete. Analysis of correlations between amphipod and polychaete tissue burdens found that the species were responding similarly to a gradient of PAH concentrations in sediment; however, when the associations between concentrations in tissue and exposure matrix (e.g. sediment, IW) were examined the interpretations were less clear. Concentrations of PAHs in IW and sediment indicated that the partition coefficient (Koc) was generally 2 orders of magnitude higher than expected for LPAHs and highly variable between sites for HPAHs. When Koc was re-calculated using free PAH, it became much less variable and was uniformly elevated above the predicted values. The BAFloc (lipid/organic carbon normalized bioaccumulation factor) in the polychaete was generally consistent over the series of PAHs, as expected, and when metabolism and pre-steady state conditions were considered, partitioning of PAHs between tissue and sediment was relatively close to the theoretical maximum. Despite much lower than predicted IW concentrations, the LPAH bioconcentration factors (BCF) for the amphipod were close to expected, but the HPAH BCFs were close to the predicted values only when expressed in terms of the free PAH. From these data, and previous studies, we conclude that there was a significant reduction in bioavailability of HPAHs to R. abronius due to partitioning of HPAHs to dissolved organic carbon. Bioaccumulation . Bioconcentration . PAHs . Sediment-water partitioning . Interstitial water . Infauna Full text in pdf format PreviousNextExport citation RSS - Facebook - Tweet - linkedIn Cited by Published in MEPS Vol. 123. Publication date: July 20, 1995 Print ISSN:0171-8630; Online ISSN:1616-1599 Copyright © 1995 Inter-Research.

Distribution of organochlorines, polycyclic aromatic hydrocarbons, phosphorus and 137Cs in sediment profiles from Ellen Brook in Western Australia

Profile distributions are compared of organochlorines (OCs), unsubstituted polycyclic aromatic hydrocarbons (PAHs), phosphorus and 137Cs and 210Pb in sediment cores from Ellen Brook, a tributary of the Swan River in Western Australia. Distributions and concentrations of OCs, phosphorus and 137Cs clearly reflect changes in their inputs to the catchment over time, whereas the distribution and concentration of PAHs in sediments is more difficult to relate to catchment inputs. A comparison of areal concentrations of 137Cs, OCS and PAHs - calculated from concentrations in sediment profiles from Ellen Brook - suggests that 137Cs and OCs trace similar soil materials, whereas PAHs behave differently.

Mitogen Induced Proliferative Responses of Lymphocytes from Spot (Leiostomus Xanthurus) Exposed to Polycyclic Aromatic Hydrocarbon Contaminated Environments

The marine fish spot, Leiostomus xanthurus, was collected from five sites in the lower Chesapeake Bay system representing a gradient of sediment polycyclic aromatic hydrocarbon (PAH) concentrations. The proliferative responses to mitogens by anterior kidney lymphocytes were assessed using [3H]-thymidine uptake by replicating DNA. The data shows two different mitogen-dependent lymphocytic responses as the sediment PAH levels increase at the sampling sites; a suppression of the response to the T cell mitogens, concanavalin A (Con A) and phytohemagglutinin, and a sharp augmentation of the response to B cell mitogen, lipopolysaccharide (LPS), as well as to poke weed mitogen and peanut agglutinin. The magnitude of the lymphoproliferative responses correlated strongly with the total sediment PAH concentrations (r2 greater than 0.8). A similar correlation was also observed with 15 selected individual PAH compounds regardless of their molecular weights. By maintaining the fish in clean York River water for up to 24 weeks, it was possible to reverse the augmented proliferative responses to LPS of fish from all sampling sites and to increase the reduced responses to Con A, in fish from three sites, and partially in two sites where sediments were highly contaminated with PAH. These results suggest that the proliferative responses of fish lymphocytes to mitogens may be a potentially sensitive biomarker of exposure to, and effects of xenobiotics.

A record of polycyclic aromatic hydrocarbon (PAH) pollution obtained from accreting sediments of the Tamar Estuary, U.K.: Evidence for non-equilibrium behaviour of PAH

Concentrations of polycyclic aromatic hydrocarbons (PAH) were quantified throughout a 210Po-dated inter-tidal sediment core from the Tamar Estuary, U.K. in order to reconstruct the input history and investigate environmental reactivity of PAH in sediments. The profile recorded is similar to those reported in other aquatic sedimentary studies, with an approximately exponential increase in the concentrations of individual PAH from < 30 ng (g dry sediment) −1 prior to 1940 to between 100 and 1000 ng (g dry sediment) −1 in contemporary surface sediments. This corresponds to an increased input of total PAH from 0.23 to 21 mg m −2 year −1. The PAH composition is dominated by parent compounds rather than alkylated homologues and is characteristic of pyrogenic sources correlating with increased motor vehicle activity and road runoff into the Tamar. There is a remarkable compositional uniformity of PAH throughout the polluted sediment core, indicating that the biogeochemical transformation and exchange processes (sorption/leaching; microbial breakdown; photo-degradation; etc.) which are known to govern the fate of experimentally-added or petroleum-derived PAH, and which exhibit compound discrimination, appear not to affect PAH in the sediments. Using a linear free energy sediment-water exchange model to simulate the repartitioning and exchange of individual PAH between the surface-mixed layer of sediment and water, we demonstrate that the current PAH concentrations in sediments are between 2 and 5 orders of magnitude greater than those expected from equilibrium partitioning with observed water concentrations. This implies that the PAH input to the sediments has been compositionally uniform and that the PAH are chemically inert. Sorptive exchange with the aqueous phase and hence the potential bioavailability of PAH appear restricted by the existence of occluded and other micro-morphologically inert forms of particle-bound PAH.

Ecotoxicological effects of creosote contamination on benthic microbial populations in an estuarine environment†

AbstractEcotoxicological effects of creosote contamination on benthic bacterial communities in the Elizabeth River, Virginia were investigated using both structural and functional microbial parameters. Parameters included direct counts, viable counts of heterotrophs and “cresol‐utilizers”, and bacterial production determined using the tritiated thymidine uptake method. Ancillary data included temperature, salinity, Eh profiles, concentrations of polycyclic aromatic hydrocarbons (PAHs), sediment granulometry and total organic carbon. Two reference stations in relatively nonpolluted areas were sampled for comparative data. Results indicated that cell specific and total heterotrophic bacterial production were depressed in a dose‐dependent manner with increasing sediment PAH concentrations. Sediment properties and seasonal changes in temperature appeared to modify the effects of PAHs on bacterial production. Direct bacterial counts and viable counts of total heterotrophs were depressed in the most contaminated sediments. Evidence of creosote adaptation was equivocal, with cresol‐utilizer densities not significantly elevated at contaminated stations. The presence of creosote was associated with shifts of Eh toward more negative values compared to nonpolluted sediments. Toxicants which reduce benthic bacterial production may indirectly impact other trophic groups through aberrant cycling of carbon or nutrients. Of the parameters examined, the tritiated thymidine production assay was found to be the most sensitive for detection of ecotoxicological effects.

The distribution of polycyclic aromatic hydrocarbons in the surficial sediments of Penobscot Bay (Maine, USA) in relation to possible sources and to other sites worldwide

Sediments from the Penobscot Bay region of the Gulf of Maine were analyzed by HPLC and GC-MS for polycyclic aromatic hydrocarbons (PAHs). Total PAH concentrations ranged from 286 to 8794 ppb (dry weight) and formed a distinct gradient decreasing seaward from the head. Gradients of decreasing concentration were also measured in the various harbors in the bay. PAH composition was uniform throughout Penobscot Bay. Atmospherically transported particulate combustion products are hypothesized as a major source of PAH contamination. Sedimentary PAH concentrations from around the world which have been reported in the literature are compiled in a Table. PAH levels in Penobscot Bay sediments fall within the range found in industrialized regions throughout the world and are significantly higher than would be expected for an area previously considered to be uncontaminated.