Showing papers on "Bioaccumulation published in 2000"
TL;DR: A review is presented of bioaccumulation of organic substances in organisms, especially fish, including the incentives for developing a tiered predictive approach for addressing the large number of chemicals of commerce.
666 citations
TL;DR: The addition of dimercaptosuccinate to arsenic-contaminated soils may provide a way to promote arsenic bioaccumulation in plant shoots, a process that will be essential for the development of an efficient phytoremediation strategy for this element.
Abstract: The bioaccumulation of arsenic by plants may provide a means of removing this element from contaminated soils and waters. However, to optimize this process it is important to understand the biological mechanisms involved. Using a combination of techniques, including x-ray absorption spectroscopy, we have established the biochemical fate of arsenic taken up by Indian mustard (Brassica juncea). After arsenate uptake by the roots, possibly via the phosphate transport mechanism, a small fraction is exported to the shoot via the xylem as the oxyanions arsenate and arsenite. Once in the shoot, the arsenic is stored as an AsIII-tris-thiolate complex. The majority of the arsenic remains in the roots as an AsIII-tris-thiolate complex, which is indistinguishable from that found in the shoots and from AsIII-tris-glutathione. The thiolate donors are thus probably either glutathione or phytochelatins. The addition of the dithiol arsenic chelator dimercaptosuccinate to the hydroponic culture medium caused a 5-fold-increased arsenic level in the leaves, although the total arsenic accumulation was only marginally increased. This suggests that the addition of dimercaptosuccinate to arsenic-contaminated soils may provide a way to promote arsenic bioaccumulation in plant shoots, a process that will be essential for the development of an efficient phytoremediation strategy for this element.
552 citations
TL;DR: The results of this study show the importance of water chemistry in determining the bioaccumulation of the metals and metalloids into insects as well as the ability of the organisms to depurate and the mode of accumulation.
Abstract: Concentrations of mercury (Hg), methylmercury (MMHg), arsenic (As), selenium (Se), and cadmium (Cd) were measured in atmospheric deposition, stream water, and biota in two streams in western Maryland. Overall, concentrations were slightly higher in the water of the lower pH Herrington Creek tributary (HRCT). Bioaccumulation factors were also higher for HRCT compared to Blacklick Run (BLK). MMHg concentrations in biota increased with trophic level and essentially all the Hg was as MMHg in predatory insects and insectivorous/carnivorous fish. Thus, the overall trophic status of the organism was indicated by the %MMHg in its tissues. Levels of As, Se, Cd, and Hg, however, decreased with increasing trophic level. Adsorption of As to the exoskeleton of invertebrates appears to be an important accumulation mechanism. MMHg was distributed evenly throughout crayfish and fish organs, whereas As, Se, Cd, and Hg were found in higher concentrations in detoxifying organs. Concentrations in biota in this study were somewhat elevated compared to other rural sites, but were less than those of point source-contaminated sites. Overall, as atmospheric inputs to the two watersheds were similar, the results of this study show the importance of water chemistry in determining the bioaccumulation of the metals and metalloids into insects. Subsequent transfer to higher trophic levels is related to both the ability of the organisms to depurate and the mode of accumulation, either directly from water or from food.
408 citations
TL;DR: In this paper, the authors examined links between watershed characteristics and aqueous metal levels in lakes and relationships between aqueou concentrations, metal burdens in different plankton groups and in fish.
Abstract: Recent studies have emphasized the need for understanding the accumulation and fate of metal contaminants at different trophic levels and across a broad spectrum of lake types. To address both issues, metal concentrations (Hg, Zn, Cd, As, and Pb) were measured in the water, two size fractions of zooplankton, and fish from 20 lakes in contaminated to pristine watersheds in the northeastern United States. Our goals were to examine links between watershed characteristics and aqueous metal levels in lakes and relationships between aqueous concentrations, metal burdens in different plankton groups and in fish. Two pairs of metals, (1) Hg and Zn and (2) As and Pb, exhibited strong similarities both in the factors that predict their concentrations in water and in the patterns of accumulation in particular trophic levels. Aqueous concentrations of Hg and Zn were highest in cool water lakes, whereas As and Pb were highest in more eutrophic lakes in agricultural areas. Aqueous Cd concentrations were closely correlated with the land-use variables, percentage of agricultural land, and road densities. Similarly, Hg and Zn both biomagnified from small plankton (45‐202mm) to macrozooplankton (.202 mm) and from macrozooplankton to fish. In contrast, bioaccumulation of both As and Pb diminished with increasing trophic level. Although aqueous metal and zooplankton metal levels were not significant predictors of As and Pb levels in fish, metal levels in zooplankton were predictive of Hg and Zn in fish, suggesting that sources of bioaccumulation differ for different metals. Our findings demonstrate the importance of investigating upper and lower trophic levels separately, to fully understand metal transfer pathways in aquatic food webs.
319 citations
Journal Article•
TL;DR: The smaller the fish the higher the body load of metals due to various bioaccumulation processes, and the male testes and female ovaries should be compared, in order to obtain further data on the differences of accumulation of metals between males and females.
Abstract: This paper focuses on the extent of Cr, Mn, Ni and Pb bioaccumulation in the different tissues of a cyprinid fish, namely the moggel (Labeo umbratus) from Witbank Dam in the Upper Olifants River catchment, The dependence of bioaccumulation on size, gender and seasons was specifically addressed. Bioaccumulation of Cr, Mn, Ni and Pb varied between the gills, liver, muscle and skin. The gills generally had the highest metal concentrations, due to their intimate contact with the environment and their importance as an effector of ionic and osmotic regulation. The liver, in its role as a storage and detoxification organ, can also accumulate high levels of metals. Muscles and skin accumulated much less metal concentrations. These two organs must be included in biomonitoring programmes because they are consumed hy the general public. Accumulation of the metals decreased with an increase in fish length Therefore the smaller the fish the higher the body load of metals due to various bioaccumulation processes. The accumulation of Cr, Mn and Ni in the different tissues of male and female fish did not differ markedly It is suggested that the male testes and female ovaries should also be compared, in order to obtain further data on the differences of accumulation of metals between males and females The highest tissue concentrat ions of Cr, Mn, Ni and Pb with the exception of the muscle and skin tissues, were recorded in the summer of 1995. The higher metal concentrations in the summer, compared to autumn and winter, can possibly he attributed to a varied water temperature.
236 citations
TL;DR: Experiments with four types of invertebrates showed that feeding behavior and dietary uptake control bioaccumulation of cadmium, silver, nickel, and zinc, contradict the notion that metal bioavailability in sediments is controlled by geochemical equilibration of metals between porewater and reactive sulfides.
Abstract: Understanding how animals are exposed to the large repository of metal pollutants in aquatic sediments is complicated and is important in regulatory decisions. Experiments with four types of invertebrates showed that feeding behavior and dietary uptake control bioaccumulation of cadmium, silver, nickel, and zinc. Metal concentrations in animal tissue correlated with metal concentrations extracted from sediments, but not with metal in porewater, across a range of reactive sulfide concentrations, from 0.5 to 30 micromoles per gram. These results contradict the notion that metal bioavailability in sediments is controlled by geochemical equilibration of metals between porewater and reactive sulfides, a proposed basis for regulatory criteria for metals.
222 citations
TL;DR: This study shows that the trophic habits can explain the interspecific differences in Cd bioaccumulation, and indicates a very strong Cd contamination in fish collected downstream from the metal source.
200 citations
TL;DR: In this article, As and Pb levels in small and large plankton and fish were measured on three dates in Upper Mystic Lake (UML), MA, which is located in the As-contaminated Aberjona Watershed.
Abstract: This study provides strong evidence for biotic accumulation of two metals in a contaminated watershed and diminution of both metals from lower trophic levels to fish. Bioaccumulation of As and Pb in water and four food web components (particulates, two size fractions of zooplankton, and six species of fish) were measured on three dates in Upper Mystic Lake (UML), MA, which is located in the As-contaminated Aberjona Watershed. Arsenic and Pb levels in small and large plankton and fish biodiminished with increasing trophic level, but only As was elevated in lower trophic levels relative to uncontaminated food webs. Metal levels in water and biota differed by date and were lowest in the spring and, in most cases, highest in summer samples. Variation in metal accumulation in zooplankton across dates may be due to changes in metal concentrations in the aqueous and particulate phase over time. Metal burdens in fish with different feeding strategies were also compared. We found the highest As in planktivorous sp...
175 citations
TL;DR: The Sea-Nine antifoulant showed no chronic or reproductive toxicity to marine species, while TBT showed a wide range of effects on growth, development, and reproduction at levels as low as 2 parts per trillion (ppt).
166 citations
01 Jan 2000
TL;DR: In this paper, the authors present a review of the factors such as toxic effects, bioavailability, chemical concentration in the water, pH of the water and lipid content of the organisms, which are known to affect the bioconcentration of chemicals in aquatic organisms.
Abstract: Bioaccumulation of chemicals by aquatic organisms, especially fish, mussels and Daphnia, is an important criterion in risk assessment. Bioconcentration from water must be considered in context with toxicity, biotic and abiotic degradation and other physical-chemical factors in order to protect the freshwater and marine environments with their organisms. Furthermore, it is necessary to prevent human exposure from contaminated aquatic food, such as fish, mussels, and oysters. This review outlines the factors such as toxic effects, bioavailability, chemical concentration in the water, pH of the water, and lipid content of the organisms, which are known to affect the bioconcentration of chemicals in aquatic organisms. Quantitative structure-activity relationships (QSARs) for predicting the bioconcentration potential of chemicals in algae, Daphnia, mussels, and fish are presented. Specific classes of organic chemicals, such as endocrine-disrupting chemicals (EDCs), super-hydrophobic persistent organic pollutants (POPs) (2,3,7,8-tetrachlorodibenzo-p-dioxin, octachlorodibenzo-p-dioxin, Mirex, and Toxaphene), tetrachlorobenzyltoluenes (TCBTs), polybrominated benzenes (PBBz), polybrominated biphenyls (PBBs), polybrominated diphenyl ethers (PBDEs), polychlorinated diphenylethers (PCDEs), nitro musk compounds (NMCs), polycyclic musk fragrances (PMFs), and sun screen agents (SSAs) are critically reviewed and discussed. Furthermore, predictions for some metabolites, especially hydroxylated aromatics, of these chemical classes which may have endocrine-disrupting effects are made. The selected bioconcentration factors on a wet weight basis (BCFw) and on a lipid basis (BCFL) in aquatic organisms, such as algae (Chlorella sp.), water fleas (Daphnia sp.), mussels (Mytilus edulis), oysters (Crassostrea virginica), and different fish species, of these chemicals are presented in tables. Furthermore, the chemical structure, physico-chemical properties, such as selected log KOW values, and other data are compiled. In the cases where no bioconcentration factors (BCFs) were published the BCF values of chemicals in fish and mussels were predicted from QSARs using the n-octanol/water partition coefficient (KOW) as the basic parameter. A new classification scheme for organic chemicals by their hydrophobicity (log KOW) and by their worst-case bioconcentration factors on a lipid basis (BCFL) is also presented.
154 citations
TL;DR: Two bivalve species (Anodonta sp. and Unio pictorum) and two gastropod species (Radix ovata and Viviparus sp.) were tested as bioindicators in moderately metal-polluted Danube River habitats of Vienna, finding the gastropods showed about 20-fold higher concentrations than the bivalves, which may indicate a higher Cu regulation capacity of bivalaves.
TL;DR: Cd is the metal of most concern due to bioaccumulation through the soil-plant-animal food chain as Cd isThe only metal that might pose human or animal health risks at plant tissue concentrations that are not directly phytotoxic.
Abstract: Understanding metal bioavailability of plants in soils requires, apart from physiological processes and symbiosis with arbuscular mycorrhizal fungi, the consideration of the chemical availability in the soil solution (the intensity of the toxic exposure) and the soil's capacity to supply the metal (capacity). In this contribution we report on the time-dependent accumulation of As, Cd, Cr, Cu, Ni, Pb, and Zn in lettuce (Lactuca sativa L.). Bioassays with 17 Dutch field soils and two artificially metal-contaminated soils were carried out. Phytotoxicity was observed in soils with pH (pore water) <4.8. Metal uptake is shown to be both metal- and soil-dependent and strongly depends on the amount of water the plant transpired and the available concentration in the water. No net accumulation of As, Pb, Ni, and especially Cr was observed in most soils tested. The latter observation is in agreement with findings of Zayed et al. (Planta, 1998 206:293–299), who reported that translocation of Cr from roots to shoots is extremely limited. Internal Cd levels in the plants varied greatly among soils, whereas plant tissue concentrations of Zn and especially Cu appear to be regulated at more or less fixed levels. The 0.01 M CaCl2-extractable metal pool provides the best descriptor for the capacity of the soil to supply Cd and Zn. This enabled the development of models that are suited to predict Zn and Cd uptake by lettuce in both field soils (weathered soils) and soils to which metal salts were added, which is common practice in toxicity testing of chemicals. It is concluded that of all metals included in this study, Cd is the metal of most concern due to bioaccumulation through the soil-plant-animal food chain as Cd is the only metal that might pose human or animal health risks at plant tissue concentrations that are not directly phytotoxic. Finally, application of the models for risk assessment purposes is discussed.
Journal Article•
TL;DR: In this article, an investigation was undertaken into the hioaccumulation of Cr, Cu and Fe in the gills, liver, muscle and skin of the fish Clarias gariepinus from two sites on the Olifants River in the Kruger National Park.
Abstract: An investigation was undertaken into the hioaccumulation of Cr, Cu and Fe in the gills, liver, muscle and skin of the fish Clarias gariepinus from two sites on the Olifants River in the Kruger National Park. During 1994, four surveys (February, May, July and November) were undertaken. Metal bioaccumulation was analysed using atomic absorption spectrophotometry and was then applied to differentiate between the concentrations found at the two locations, and between all of the surveys, The greatest concentration of Cr was detected in the gills, suggesting that this was the prime site of absorption and loss of Cr to and from the aquatic environment. The concentrations of Cu and Fe were highest in the liver, which is a storage and detoxification organ for metal, followed by the gills. Mamba and Balule generally showed very little difference in the concentration of bioaccumulated metal. However, the gills as in the case of Cr generally showed high concentrations at Mamba, while the liver as in the case of Fe, showed consistently higher concentrations at Balule. The possible effects that temperature, pH, hardness and salinity have on the individual metals, as well as bioaccumulation of these metals, are discussed in detail. The continuous monitoring of the quality of water in the Olifants River is imperative for the future sustainability of the Kruger National Park.
TL;DR: In this paper, an analytical approach is described for bioaccumulation and ecotoxicology assessment studies of organophosphorous pesticides (OPs), organochlorine compounds (OCls) and polycyclic aromatic hydrocarbons (PAHs) in bivalves cultured in the Ebro Delta.
TL;DR: Comparison results on the bioaccumulation of inorganic mercury and resulting gill damages in the tropical fish, Trichomycterus zonatus, and a nordic species, Salvelinus alpinus, using radioisotope 203Hg techniques and scanning electron microscopy strongly suggest that T.Zonatus is more sensitive to inorganicMercury pollution than S. al pinus.
TL;DR: The objective of this study is to measure the toxicity of Cu, Zn & Cd in T. zillii, M. cephalus and Mysis sp.
Abstract: Coastal inland water receive discharges from different sources including industrial plants, sewage drainage, atmospheric pollution and other natural sources which lead to heavy metal pollution (Bryan, 1971). Heavy metals can affect the aquatic organisms as toxic substances in water and sediment or as a toxicant in the food chain (Zyadah, 1995). Cichlidae and Mugilidae are widely distributed in the Egyptian inland waters. They are the main source of fish food and are economically important in inland fisheries and aquaculture resources in Egypt. Mysis sp. is considered a main source of fish food. The objective of this study is to measure the toxicity of Cu, Zn & Cd in T. zillii, M. cephalus and Mysis sp., to determine the bioaccumulation rate in the fish, as well as LC50 and total mortality of each species.
TL;DR: Assessment of the toxicity of cadmium on Tubifex tubifex revealed that Cd is highly and rapidly taken up by the worm, suggesting involvement of efficient detoxification mechanisms and the ability to accumulate large amounts of Cd may represent a potential toxicological risk to predators of the worm if CD is accumulated in bioavailable forms.
Abstract: A kinetic model of trace element bioaccumulation in zebra mussels, employing experimentally determined trace element influx and efflux rates following food and water exposures, was field-tested in the Hudson and Niagara Rivers and Lakes Erie and Ontario. Ultraclean measurements of water column trace element concentrations in these waters and on suspended particles were used to predict metal concentrations in zebra mussels that were measured independently by the NOAA Mussel Watch program. Field concentrations of Ag, Cd, Cr, and Hg ranged from subpicomolar (Ag) to low nanomolar (Cr) and displayed partition coefficients between particulate and aqueous phases of 1-20 x 10 5 L kg -1 . Despite variation in bioaccumulation factors (BAF) between locations by up to 6x (for Ag), our model predicted mean body burdens of Ag, Cr, Hg, and Se that differed from measured tissue concentrations at the same sites by only 30% on average. Cd predictions matched measured values at the two lake sites but exceeded measurements atthe three river sites by 2.6-fold. Furthermore, the model predicted that, under all environmental conditions likely to prevail in natural waters, Ag, Cd, and Hg are predominantly accumulated from ingested particles, that Cr is accumulated mostly from the dissolved phase, and that the relative uptake pathway for Se varies with environmental conditions. The highest BAF was for Cd (15-64 x 10 4 ) and the lowest BAFs were for Cr and Se (1.2-2.5 x 10 4 and 0.5-2.8 x 10 4 , respectively), with Ag and Hg being intermediate (2.0-12 x 10 4 and 1.4-25 x 10 4 , respectively). The good agreement of the model with field measurements suggests, for these elements, that (a) accumulation of these elements in zebra mussels is in fact proportional to influx from food and water (that is, the organism is not actively regulating internal concentrations), and (b) we can account for the processes governing metal bioaccumulation in these animals. We conclude that for these elements the zebra mussel will be effective as a bioindicator of ambient metals in freshwater systems.
TL;DR: In this article, a 23-year time series of environmental change from a San Francisco Bay mudflat located 1 km from the discharge of a suburban domestic sewage treatment plant was presented, where samples of surface sediment, the bioindicator Macoma balthica and metals loading data were used to establish links between discharge, bioaccumulation, and effects.
Abstract: The developed world has invested billions of dollars in waste treatment since the 1970s; however, changes in ecological or biological responses are rarely associated with reductions in metal pollutants. Here we present a novel, 23yr time series of environmental change from a San Francisco Bay mudflat located 1 km from the discharge of a suburban domestic sewage treatment plant. Samples of surface sediment, the bioindicator Macoma balthica, and metals loading data were used to establish links between discharge, bioaccumulation, and effects. Mean annual Ag concentrations in M. balthica were 106 pglg in 1978 and 3.67 pglg in 1998. Concentrations of Cu declined from 287pglg in 1980 to a minimum of 24pgIg in 1991. Declining Cu bioaccumulation was strongly correlated with decreasing Cu loads from the plant between 1977 and 1998.Relationships with bioaccumulation and total annual precipitation suggested that inputs from nonpoint sources were most important in controlling Zn bioavailability during the same period. Ecoepidemiological criteria were used to associate failed gamete production in M. balthica to a metals-enriched
TL;DR: Manipulation of AVS by oxidation of naturally anoxic sediments allowed use of metal concentrations typical of nature and evaluation of processes important to chronic metal exposure and showed that AVS or porewater (PW) metals controlled bioaccumulation in only 2 of 15 metal-animal combinations.
Abstract: An 18-day microcosm study was conducted to evaluate the influence of acid volatile sulfides (AVS) and metal additions on bioaccumulation from sediments of Cd, Ni, and Zn in two clams (Macoma balthica and Potamocorbula amurensis) and three marine polychaetes (Neanthes arenaceodentata, Heteromastus filiformis, and Spiophanes missionensis). Manipulation of AVS by oxidation of naturally anoxic sediments allowed use of metal concentrations typical of nature and evaluation of processes important to chronic metal exposure. A vertical sediment column similar to that often found in nature was used to facilitate realistic biological behavior. Results showed that AVS or porewater (PW) metals controlled bioaccumulation in only 2 of 15 metal-animal combinations. Bioaccumulation of all three metals by the bivalves was related significantly to metal concentrations extracted from sediments (SEM) but not to [SEM − AVS] or PW metals. SEM predominantly influenced bioaccumulation of Ni and Zn in N. arenaceodentata, but Cd bi...
TL;DR: In this article, a juvenile rainbow trout (Oncorhynchus mykiss) was exposed to three [14C]-polychlorinated alkanes (PCAs) at nominal concentrations of 1.5 and 15 μg/g for 40 d, followed by 160 d of clean food, to measure bioaccumulation parameters and biotransformation.
Abstract: Juvenile rainbow trout (Oncorhynchus mykiss) were exposed to three [14C]-polychlorinated alkanes (PCAs) (C10H15.3Cl6.7, C14H23.3Cl6.7, and C18H31.4Cl6.6) at nominal concentrations of 1.5 and 15 μg/g for 40 d, followed by 160 d of clean food, to measure bioaccumulation parameters and biotransformation. These PCAs are identical in carbon-chain length and chlorine content to industrial chlorinated paraffin products, although their method of synthesis differs from that of chlorinated paraffin products. Half-lives ranged from 26 to 91 d, biomagnification factors ranged from 0.9 to 2.8, and both exhibited increasing trends with increasing carbon-chain length. Data from this work and others on PCAs were used to determine biotransformation rates and to examine quantitative structure-activity relationships for bioaccumulation and biotransformation. Quantitative structure-activity relationships developed for half-life and biomagnification factor showed positive linear relationships with the number of carbon atoms, of chlorine atoms, of total carbon and chlorine atoms, and log Kow. The PCA biotransformation rates (per day) ranged from −0.00028 to 8.4 and exhibited negative relationships with the number of carbon atoms, of chlorine atoms, of total carbon and chlorine atoms, and log Kow. Results suggest that PCAs with a total number of carbon and chlorine atoms between 22 and 30 are slowly, or are not, biotransformed in juvenile rainbow trout. Increasing carbon-chain length and chlorine content result in greater bioaccumulation of PCAs by reducing partition-based (i.e., diffusion) and metabolic (i.e., biotransformation) elimination processes. High bioaccumulation potential and low biotransformation rates of medium (C14-18) and long (C18-30) carbon-chain PCAs and highly chlorinated PCAs indicate that information is needed regarding the environmental concentrations of these PCAs in aquatic food chains.
TL;DR: This work and other studies indicate that for many deposit feeders, ingested sediment can be the primary source for the bioaccumulation of hydrophobic toxicants.
Abstract: A mass-balance bioaccumulation model was used to examine the bioaccumulation of benzo[a]pyrene (BaP) from ingested sediment by the deposit-feeding polychaete Abarenicola pacifica over a series of experiments employing nine different sediments Through selective ingestion of fine-grained material, the worm was able to increase the BaP content of ingested sediment by 10-35% above that of the bulk material During digestion, an average of 5-21% of the ingested BaP was absorbed from gut contents The relative importance of ingestion as a route of BaP uptake was dependent on the time period of observation Initial uptake of BaP was postulated to come from absorption of dissolved BaP across the body wall since, after short periods of exposure (<24 h), only 3-38% of observed BaP tissue concentrations could have been derived from ingested material With time and with increased feeding activity, however, ingested sediment became the major source of BaP to the organism After 72 h of exposure, 36-119% of the tissue BaP (mean = 77%) was estimated to have been derived from dietary absorption of ingested material, and with continued exposure the dietary route is likely to be as great or greater as the relative significance of the initial uptake from the dissolved phase diminishes This work and other studies indicate that for many deposit feeders, ingested sediment can be the primary source for the bioaccumulation of hydrophobic toxicants
01 Nov 2000
TL;DR: In this article, the induction of hepatic CYP1A in fish by certain classes of chemicals has been suggested as an early warning system, a "most sensitive biological response" for assessing environmental contamination conditions.
Abstract: Polycyclic aromatic hydrocarbons (PAHs), dioxins, dibenzofurans, and polychlorinated biphenyls (PCBs) present in polluted environment induce cytochrome P4501A (CYP1A) isozyme in fish, which in turn results in a marked increased production of carcinogenic metabolites from PAHs. The induction of hepatic CYP1A in fish by certain classes of chemicals has been suggested as an early warning system, a "most sensitive biological response" for assessing environmental contamination conditions. This has implications for human fish consumption, as well as for the health status of aquatic organisms. Correlation between elevated CYP1A and altered steroid metabolism and decreased reproductive success has been pointed out. The induction of CYP1A and associated enzyme activities has now been confirmed in a number of field studies. Cases where these biomarkers have been studied in field conditions will be presented. Special emphasis will be given to field studies in which the induction of CYP1A activity, 7-ethoxyresorufin O-deethylase (EROD) activities and immunochemical detection of CYP1A in leaping mullet and common sole are used as a biomarker for PAH- and/or PCB-type pollutants along the Izmir Bay on the Aegean Sea. Organisms are often exposed to complex mixtures of pollutants, including polychlorinated biphe- nyls (PCBs), polychlorinated dibenzodioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), poly- cyclic aromatic hydrocarbons (PAHs), alkyltin compounds, and metals. Pollutants that bioaccumulate in the organism first cause effects at the molecular and cellular levels. This may lead to adverse effects in the organism, which in turn may cause changes at the population and the community level in the years to come. Fish populations living in highly polluted areas often have high incidences of gross pathological lesions and neoplasms that may be associated with the elevated levels of toxic chemicals in the sediments (1). The high levels of neoplasms in fish collected from a creosote (mixture of petroleum products) polluted site in Puget Sound, WA, USA were reported (2). Even though chemical analyses are able to measure a wide range of pollutants quantitatively and accurately, the complex mixture of chemical pollutants cannot be fully assessed. Furthermore, it does not reveal the impact of chemical pollution on the aquatic environment. The use of biochemical markers fulfills this purpose. Biomarker responses are, broadly speaking, of two kinds: those that measure only
TL;DR: The characteristics of bioaccumulation demonstrate that P. walkeri is a circumpolar species with the potential to be a standard biological indicator for use in monitoring programmes of Antarctic nearshore ecosystems and the use of model prediction provide further support to utilise these organisms for biomonitoring.
TL;DR: In this paper, organochlorine (OC) pesticides in ice algae, phytoplankton, and micro-zooplankton during summer months and in meso-and macro-zoplankton throughout 1993 in the Canadian archipelago (Barrow Strait) were compared with seasonal changes in seawater (upper 50 m) concentrations.
Abstract: Organochlorine (OC) pesticides in ice algae, phytoplankton, and microzooplankton during summer months and in meso- and macrozooplankton throughout 1993 in the Canadian archipelago (Barrow Strait) were compared with seasonal changes in seawater (upper 50 m) concentrations. α-HCH, HCB, ΣCHL, dieldrin, γ-HCH, ΣPCB, and ΣDDT ( 100 ng g-1 lipid, >10 ng g-1 wet weight) than ice algae and phytoplankton. Highest OC concentrations occurred in macrozooplankton during the winter−spring period of ice cover. Concentrations for all compounds except HCHs decreased during the open water period when bioaccumulation factors (BAFs) (tissue:water concentrations) were maximum (106−107 lipid weight basis) for CHBs and ΣDDT and minimum (103−104) for HCHs. BAFs on a wet weight basis mirrored lipid-based values but were approximately 10-fold lower. Meso- and macrozooplankton had minimal BAFs in July and Aug...
TL;DR: Oyster soft tissue, shell and sediments were analyzed for Cd, Cr, Cu, Fe, Mn, Pb, and Zn, suggesting a good discrimination against these metals by oysters.
Abstract: Oysters and sediment have been collected from most major US Gulf of Mexico bays and estuaries each year since 1986. Selected samples of oyster soft tissue, shell and sediments were analyzed for Cd, Cr, Cu, Fe, Mn, Pb, and Zn for this study. Concentrations varied considerably from place to place but ratios of metals remained relatively constant. Cu and Zn are greatly enriched in oyster tissues, which is related to their physiological function. Cd is enriched in oyster shell because of the easy substitution between Cd and Ca. The concentrations of Pb and Cr in oysters are significantly lower than that in sediment, suggesting a good discrimination against these metals by oysters. Metal variations are a result of both nature and human activity.
TL;DR: Rainbow trout accumulated more silver than the other teleosts, and were the only species to suffer significant mortality, effects likely associated with added salinity stress, and elasmobranchs accumulated silver 5-15-fold faster than the threeteleosts.
TL;DR: It appears as though aqueous selenium enrichment was capable of having a profound effect on mercury bioaccumulation in this system but at the cost of causing a high incidence of gross abnormalities in fish.
Journal Article•
TL;DR: The available data indicate that sediment-water partitioning, bioaccumulation, and the toxicity responses for tributyltin (TBT) are predictable when using some of the assumptions and tenets of the equilibrium partitioning method, toxicokinetic modeling, and critical body residue (CBR) approach.
Abstract: The available data indicate that sediment-water partitioning, bioaccumulation, and the toxicity responses for tributyltin (TBT) are predictable when using some of the assumptions and tenets of the equilibrium partitioning method, toxicokinetic modeling (1CFOK), and critical body residue (CBR) approach. Because TBT is ionizable, its speciation is strongly affected by pH, which appears to cause large variations in the octanol-water partition coefficient. In marine systems, and in freshwater systems with high pH, TBT occurs predominantly in the hydroxide form, which may explain the hydrophobic properties and its EqP behavior. Organic carbon in sediment (> 0.2%) appears to be the major controlling factor for sediment-water partitioning. The equilibrium organic carbon-normalized sediment-water partition coefficient (Koc) in marine environments is approximately 32,000 (log10 Koc approximately 4.5), which was determined from direct measurement and confirmed by the relationship between the lipid-normalized bioconcentration factor (BCF) in porewater and the biota-sediment accumulation factor (BSAF). The conclusion that sediment-water partitioning of TBT in marine systems follows EqP is supported by the similarity between its Kow and Koc and the correlation between the sediment-water partition coefficient (Kp) and sediment TOC, which results from the influence of organic carbon on pore-water concentrations. Even though the rates of uptake and elimination control tissue residues and lipid content appears to have no bearing on the amount of TBT that is accumulated, the species specific BSAF is useful for examining bioaccumulation, sediment-water partitioning, and the toxicity response. Although TBT is hydrophobic and appears to have a propensity to accumulate in lipid, the rates of uptake and elimination, not thermodynamics, appear to control whole-body tissue concentrations. Support for a toxicokinetic approach for predicting tissue residues is found in BCF and BSAF values for several species that are far in excess of that predicted by simple thermodynamic partitioning and in the comparisons of observed and predicted bioaccumulation values based on toxicokinetic coefficients. This observation is counter to the assumption of EqP that the route of uptake is of no consequence under equilibrium conditions. For TBT, it appears that kinetics determine tissue residues and that body lipid is important only for regulating the toxic response, not the amount bioaccumulated. Unlike those for neutral hydrophobic organic compounds, the toxicokinetics for this one toxicant are highly variable in diverse species but relatively accurate in predicting the amount bioaccumulated and the resulting toxicity response. For the CBR approach to be useful, a relatively constant tissue residue for a given biological response is necessary. Several studies support the CBR approach because certain biological effects, such as mortality and growth inhibition, occur at a relatively constant TBT tissue concentration. For TBT, the lethal whole-body tissue concentration affecting 50% of individuals (LR50) exhibits little variation, occurring at approximately 48 micrograms/g (166 nmol/g) dry weight in a range of species. Direct evidence and correlation of the LC50 and the bioconcentration factor (BCF) support this observation. Impaired growth, a sublethal response, also appears to be associated with a relatively constant tissue concentration, which has also been demonstrated by direct measurement and indirectly by regression of the BCF and LOEC. The lowest-observed-effect tissue residue (LOER) associated with impaired growth for several species was approximately 3 micrograms/g (10.4 nmol/g) dry wt. Because of the small number of studies linking growth impairment and tissue concentrations, additional studies are needed to confirm these values. (ABSTRACT TRUNCATED)