Bioaccumulation Of PAHs Research Articles

Immune effects of HFO on European sea bass, Dicentrarchus labrax, and Pacific oyster, Crassostrea gigas

The European sea bass, Dicentrarchus labrax, and the Pacific oyster, Crassostrea gigas, were exposed to a soluble fraction of heavy fuel oil for 5 and 9 days, respectively. The organisms were then transferred to non-contaminated seawater for 1 month. The bioaccumulation and elimination of PAHs in contaminated tissues were dissimilar between species. In fish, acenaphthene and naphthalene were detected and naphthalene was still detectable 30 days after the beginning of the recovery period. In oysters, on the other hand, pyrene and phenanthrene were bioaccumulated and 14 days after exposure no more PAHs were detected. Concerning innate immune parameters, the increase of haemolytic activity of the alternative complement pathway in fish and the reduction of phenoloxidase activity in oysters endured, respectively, 1 and 2 weeks in contaminated organisms. This indicates that these two enzymatic cascades could be quite useful for monitoring pollution by oil.

Sediment contamination, bioavailability and toxicity of sediments affected by an acute oil spill: Four years after the sinking of the tanker Prestige (2002)

Sediment contamination and three bioassays were used to determine the sediment quality four years after an oil spill (Prestige, 2002): the Microtox® test, a 10-day bioassay using the amphipod Ampelisca brevicornis, and a polychaete 10-day toxicity test with the lugworm Arenicola marina. In addition, bioaccumulation of PAHs was examined in the polychaete after 10 days of exposure. The results obtained from the toxicity tests and bioaccumulation analyses were statistically compared to the sediment chemical data, in order to assess the bioavailability of the contaminants, their effects, and their relationship with the oil spill. The sediments studied were from two areas of the Galician Coast (NW Spain): the Bay of Corme-Laxe and the Cíes Island, located in the Atlantic Island National Park. The results point to a decrease in contamination with respect to previous studies and to the disappearance of the acute toxicity four years after the oil spill. However an important bioaccumulation of PAHs was detected in the organisms exposed to sediments from Corme-Laxe, suggesting that despite the recovery of the environmental quality of the area, effects in the biota might be occurring.

Using the polychaete Arenicola marina to determine toxicity and bioaccumulation of PAHS bound to sediments

The present study was conducted to evaluate a sediment toxicity and bioavailability test with the polychaete Arenicola marina as a potential tool to assess sediments contaminated by oil spills. A bioassay using the lugworm Arenicola marina was carried out in order to determine toxicity and bioaccumulation associated with the contaminants present in the fuel oil extracted from a sank tanker. After 10 and 21 days of exposure to sediments with different proportions of fuel oil (0.5, 1, 2, 4 and 8%) polychaetes were sampled to determine the mortality and the levels of individual PAHs in the organisms. During the experiment, mortality was recorded and the concentration (percentage of fuel oil) that provokes the mortality of the 50% of the Arenicola marina population exposed was calculated for both sampling dates (LC50(10) = 6.4%; LC50(21) = 2.4%). Bioaccumulation was mainly produced for fluoranthene, pyrene, benzo(b)fluoranthene and benzo(k)fluoranthene, whereas phenantrene and anthracene where initially accumulated and then metabolized. The results obtained in the present study suggest Arenicola marina can be a suitable species for assessing PAHs toxicity and bioaccumulation as part of oil spill management.

Relationship between heavy fuel oil phytotoxicity and polycyclic aromatic hydrocarbon contamination in Salicornia fragilis

Greenhouse experiments were carried out to study the effects of heavy fuel oil contamination on the growth and the development of Salicornia fragilis Ball and Tutin, a salt-marsh edible species. Plants were sampled in spring at the "Aber du Conquet" (Finistère, France), and artificially exposed by coating shoot sections with N degrees 6 fuel oil or by mixing it in their substratum. The impact of petroleum on plant development was followed by phytotoxicity assessments and PAH shoots assays. The plants exhibited visual symptoms of stress, i.e. chlorosis, yellowing, growth reduction and perturbations in developmental parameters. The contamination of plants by shoot coating appeared to be less than through soil. Moreover, the increase of the degree of pollution induced more marked effects on plants, likely because of the physical effects of fuel. However, bioaccumulation of PAHs in shoot tissues was also found to be significant, even at very low levels of contamination, and highly related to the conditions of exposure to oil. The strong relationships between the PAH contents of Salicornia plants and growth reduction suggest a chemical toxicity of fuel oil, compounds like PAHs being known to inhibit physiological processes in plants.

Effects of sediment organic matter quality on bioaccumulation, degradation, and distribution of pyrene in two macrofaunal species and their surrounding sediment

Sediment dwelling macrofauna (infauna) are important vectors for the transfer of sediment-associated contaminants to higher trophic levels. Sedimenting organic matter constitutes an important food source for all benthic organisms and changes seasonally in terms of quantity and quality. Sediment organic matter (SOM) quality affects organism activity and feeding behaviour, and is therefore also likely to affect contaminant fate in benthic systems. We investigated the impact of SOM quality (enrichment with either labile Tetraselmis sp. or refractory lignin) on the accumulation and metabolism of sediment-associated pyrene in Nereis diversicolor (Annelida) and Amphiura filiformis (Echinodermata), as well as the combined effect of SOM quality and infaunal bioturbation on pyrene distribution and metabolism in the sediment. After 45 d of exposure, SOM quality almost doubled pyrene bioaccumulation in both species, while pyrene metabolism remained unaffected. Metabolites comprised approximately 80% of the total tissue pyrene in N. diversicolor and approximately 40% in A. filiformis. A. filiformis arms contained one fifth of the disk pyrene concentration. Approximately 20% of the pyrene found in A. filiformis arms was found to be covalently bound to, e.g. DNA, RNA or proteins, thus reducing pyrene bioavailability to arm-cropping predators. The sedimentary pyrene distribution and metabolism was species-dependent, but correlated poorly with prevailing knowledge on species-specific bioturbation patterns. This was attributed to the comparably high biodegradability of the contaminant thus altering its sorptive characteristics and function as inert tracer. Subduction of pyrene and metabolites occurred, and the fraction of pyrene covalently bound to SOM increased with depth, thereby removing pyrene from the bioavailable pool. Our results imply that bioaccumulation and trophic transfer of sediment-associated PAH should increase following fresh organic matter input, e.g. after sedimentation of phytoplankton blooms. We stress the importance of considering behavioural characteristics of infauna and the trophic situation of the system when assessing fate and effects of sediment-associated contaminants.

Application of surrogate methods for assessing the bioavailability of PAHs in sediments to a sediment ingesting bivalve

The usefulness of two surrogate methods for rapidly determining the bioavailability of PAHs in hydrocarbon-contaminated marine sediments was assessed. Comparisons are made between the PAHs accumulated by the benthic bivalve, Tellina deltoidalis, and the extractable-PAHs determined using a 6-h XAD-2 resin desorption method and a 4-h gut fluid mimic (GFM) extraction method. There were significant positive relationships between PAH bioaccumulation by the bivalves and sediment PAH concentrations. These relationships were not improved by normalising the sediment PAH concentrations to the organic carbon concentration. The average percentage lipid content of the bivalves was 1.47 ± 0.22% and BSAFs for total-PAHs ranged from 0.06 to 0.80 (kg OC/kg lipid). The XAD-2 and GFM methods both extracted varying amounts of PAHs from the sediments. Low concentrations of PAHs were extracted by the GFM method (0.2–3.6% of total-PAHs in sediments) and the GFM results were inadequate for generalising about the bioavailability of the PAHs in the sediments. The XAD-2 method extracted greater amounts of PAHs (3–34% of total-PAHs in sediments), however, the total-PAH concentrations in the sediments provided a better, or equally good, prediction of PAH bioaccumulation by T. deltoidalis. The results indicated that these methods required further development before they can be applied routinely as surrogate methods for assessing the bioavailability of PAHs in sediments. Future research should be directed towards lowering detection limits and obtaining comparative data for a greater range of sediment types, contaminant classes and concentrations, and organisms of different feeding guilds and with different gut chemistry.

Experimental results on effects of capping on fluxes of persistent organic pollutants (POPs) from historically contaminated sediments

One option proposed for the remediation of Oslo harbour, Norway, has been dredging of up to 700 000 m 3 of contaminated sediments and deposition at 60 m depth in a nearby intermittently anoxic fjord basin. Contaminant retention in the deposit area will be favoured by metal sulphide precipitation and the current absence of sediment dwelling organisms. In addition capping will be performed to protect against future fjord recovery and recolonisation with benthic animals. In order to assess the risk of contaminant leakage from the deposit area a long-term mesocosm experiment was performed to simulate the three expected successive phases: (1) anoxic basin water, (2) oxic water and (3) oxic water and presence of bioturbators. Fluxes of dissolved, bioavailable contaminants (PAHs, PCBs and DDTs) were measured by uptake in passive membrane samplers (SPMDs) located in the source seawater and downstream 0.25 m 2 boxes with capped and non-capped harbour sediments. The experiment showed that pyrene and fluoranthene was released from no-cap treatments at high rates (2545 and 830 pmol m − 2 day − 1 , respectively) during the initial, anoxic phase. The majority of components showed, however, maximum fluxes during the final, bioturbation phase: 243 pmol m − 2 day − 1 sumKPAH (six of the most cancerogenous PAHs), 19.6 pmol m − 2 day − 1 of sumPCB 7 and 13.6 pmol m − 2 day − 1 DDT. Cap layers reduced fluxes and bioaccumulation of PAH in the gastropode Hinia reticulata by 89–100%. Fluxes and bioaccumulation of PCBs was not reduced to the same extent suggesting that external sources may be relatively more important for PCB than for PAH levels in this organism. A minor release of PAH-components from one of the cap treatments indicated slight contamination from fossil fuel or explosives applied during production of the machined sand used as cap material for this treatment. Differences due to cap thickness variations between 10 and 50 cm were not found throughout the experimental period of 34 months.

Evaluation of PAH bioaccumulation and DNA damage in mussels ( Mytilus galloprovincialis) exposed to spilled Prestige crude oil

We analyzed the hydrocarbon composition of the Prestige oil as it reached the shores, its solubility in sea water, its bioaccumulation, and the genotoxic damage associated to oil exposure, using Mytilus galloprovincialis as sentinel organism. Mussels were exposed to two oil volumetric ratios (1:500 and 2:500) for 12 days. Great concentrations of total polycyclic aromatic hydrocarbons (TPAH) have been obtained, being in general higher in the samples from the dose of 1:500, both in sea water (55.14 vs. 41.96 μg/l) and mussel tissue (16,993.80 vs. 17,033.00 μg/kg), probably due to the great tendency of these compounds to link to particles in water. Comet assay results reflected an increase in the DNA damage associated to oil exposure, higher in the mussels exposed to the higher aqueous TPAH content. In the view of our results, the importance of the evaluation of biodisponibility, bioaccumulation and DNA damage in the assessment of the effects of xenobiotic pollutants to marine environments could be highlighted.

Toxicokinetics and time-dependent PAH toxicity in the amphipod Hyalella azteca.

The relationship between toxicokinetics and time-dependent PAH toxicity to Hyalella azteca was examined to test the constant critical body residue (CBR) model. A constant CBR model is based on the assumption that the body residue for 50% mortality is constant for each PAH across exposure times. With a constant CBR, kinetic parameters determined through kinetic experiments would be similar to those estimated from time series toxicity data. Time-dependent toxicity was investigated using three types of data: time series LCW data, LT50(c), and CBR values measured at multiple exposure times for live and dead animals. Kinetic parameters were measured independently. The constant CBR model did not predict the PAH toxicity time course for H. azteca. Since a first-order kinetic model predicted the bioaccumulation of the parent PAH except for naphthalene, this result is not due to a failure to predict the internal dose (body residue). The influence of metabolites on toxicity was negligible except for naphthalene. The LC50 values at multiple exposure times decreased to an incipient lethal concentration after H. azteca reached steady state. Measured CBR values also decreased with increasing exposure time. Thus, the time course of PAH toxicity is determined not only by the bioconcentration kinetics but also by the cumulative toxicity with increasing exposure time. Therefore, time-to-death or hazard models must be developed as a complement to toxicokinetic models to describe and predict the toxicity time course.

The Use of Spectrofluorimetry for Monitoring the Bioaccumulation and the Biotransformation of Polycyclic Aromatic Hydrocarbons in Daphnia magna

A rapid and direct spectrofluorimetric method was tested in order to monitor the bioaccumulation of PAHs in Daphnia magna in a control media. After exposure to water containing benzo[ a ]pyrene or fluoranthene, daphnids were put in solvent, sonicated, and filtered. The fluorescence spectrum observed in the filtrate was recorded. Results were compared to HPLC measurements of the same pools of organisms. In fluoranthene experiments, the fluorescence peak of the daphnid extract spectrum was linearly related to the PAH content as measured with HPLC. In benzo[ a ]pyrene experiments, other fluorescent compounds progressively appeared in the sample. They were assumed to be metabolites. A linear regression involving fluorescence intensities at two different wavelengths was necessary for a satisfactory correlation with HPLC measurements. A water extraction was performed to isolate metabolites. None or very few fluoranthene metabolites were isolated in the aqueous phase, whereas increasing benzo[ a ]pyrene metabolites were observed while the exposure time increased.

The Use of Spectrofluorimetry for Monitoring the Bioaccumulation and the Biotransformation of Polycyclic Aromatic Hydrocarbons in Daphnia magna

A rapid and direct spectrofluorimetric method was tested in order to monitor the bioaccumulation of PAHs in Daphnia magna in a control media. After exposure to water containing benzo[ a ]pyrene or fluoranthene, daphnids were put in solvent, sonicated, and filtered. The fluorescence spectrum observed in the filtrate was recorded. Results were compared to HPLC measurements of the same pools of organisms. In fluoranthene experiments, the fluorescence peak of the daphnid extract spectrum was linearly related to the PAH content as measured with HPLC. In benzo[ a ]pyrene experiments, other fluorescent compounds progressively appeared in the sample. They were assumed to be metabolites. A linear regression involving fluorescence intensities at two different wavelengths was necessary for a satisfactory correlation with HPLC measurements. A water extraction was performed to isolate metabolites. None or very few fluoranthene metabolites were isolated in the aqueous phase, whereas increasing benzo[ a ]pyrene metabolites were observed while the exposure time increased.

Fate of sediment-associated pyrene and benzo[a]pyrene in the freshwater oligochaete Lumbriculus variegatus (Müller)

Bioaccumulation, depuration and biotransformation of radiolabelled pyrene and benzo[a]pyrene were studied in the freshwater oligochaete Lumbriculus variegatus in spiked Lake Mekrijärvi (Eastern Finland) sediment in two sets of experiments (I and II). In experiment I bioaccumulation, depuration and biotransformation of PAHs were studied. In experiment II biotransformation was investigated further using three different solvent extractions and the ability of L. variegatus to biotransform was based on the change of proportion of the parent PAH in tissue. Bioaccumulation of both chemicals was fast and an apparent steady level was reached within a week. Biotransformation results obtained by solvent extractions were in agreement with each other, although hexane appeared to be less efficient solvent for B[a]P than chloroform:methanol or ethyl acetate:acetone/cyclohexane. The relative proportion of parent PAHs in tissues decreased continously during the 504 and the 336 h exposures in experiments I and II, respectively. After 336 h exposure in experiment II, approximately 60% of pyrene and 90% of B[a]P associated radioactivity was still in the parent compound. Depuration of the parent compounds in clean sediment was fast. Most of the parent chemicals were depurated within 72 h but the possible biotransformation products remained mainly in tissues. Feeding behavior of the animals (sediment ingesting vs. noningesting) did not affect pyrene biotransformation but the proportion of parent B[a]P in tissues was larger in feeding animals. This was probably due to faster uptake rate of B[a]P to feeders than nonfeeders and slow biotransformation rate of the chemical. Our results suggest that biotransformation of pyrene and B[a]P in L. variegatus is likely and it should be taken into account when studying bioaccumulation of PAHs in assessing hazard of sediment contamination.

Bioaccumulation, biotransformation and DNA-binding of PAHs in feral eel ( Anguilla anguilla), exposed to polluted sediments: A field survey

Bioaccumulation, biotransformation and DNA-binding of PAHs in feral eel ( Anguilla anguilla), exposed to polluted sediments: A field survey

Bioaccumulation, biotransformation and DNA binding of pahs in feral eel (Anguilla anguilla) exposed to polluted sediments: A field survey

AbstractSamples of sediment and eel taken from six sites in Amsterdam with different levels of water pollution were analyzed for 16 parental PAHs In addition, biliary PAH metabolites and hepatic PAH‐DNA adducts were determined in the eel to evaluate biomomtoring techniques for PAH exposure There was a clear difference between PAH profiles in sediments and eel Mainly two‐ and three‐ring PAHs were detected in eel, whereas four‐ring PAHs predominated in the sediments Because PAH bioaccumulation was highest in eel from the reference sites, tissue levels of the parental PAH are probably not the most accurate monitor of PAH exposure in fish An elevated excretion of 1 OH pyrene (determined by synchronous scan fluores cence) was observed in the bile of fish from three of the four polluted sites, indicating that this parameter may be used as a biomarker for PAH exposure A significant increase in PAH‐DNA adduct levels (determined by 32P postlabeling) was observed in the liver of eel from all polluted sites Therefore, this parameter seems to be a sensitive biomarker for exposure to mutagenic and carcinogenic PAHs

The Fates Of Aromatics Model (FOAM): Description, application, and analysis

The Fates Of Aromatics Model (FOAM) evaluates the hypothesis that transport, degradation, and bioaccumulation of polycyclic aromatic hydrocarbons (PAH's) in aquatic systems can be forecast from fundamental chemical characteristics of this homologous series of compounds. Molecular weight, ring number, melting point, octanol: water partition coefficient, and a light absorption spectrum are used to calculate rates of dissolution, volatilization, photolytic degradation, sorption, and bioaccumulation of specific PAH's in lotic and lentic environments. FOAM forecast spatial and temporal concentrations of dissolved anthracene within 15 percent of concentrations measured in lotic microcosms. The model overestimated periphyton accumulation of anthracene by 425 percent, but was within 40–50 percent of measured concentrations in stream sediments and papershell clams. Patterns of naphthalene and benzo(a)pyrene flux simulated by FOAM agreed qualitatively with results reported for lentic microcosms. Monte Carlo error analysis of FOAM identified 7 parameters that contributed importantly to imprecision in forecasts of anthracene fate. The rank order of correlation of these parameters with prediction error changes during the course of a simulation.