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1.
Pseudopleuronectes americanus were chronically exposed to Hibernia crude oil in sediments, for 4 months. Oil was added to sediments at five concentrations between 0.09 and 4.5 mg/g (dry weight) and was 0.10–0.90 mg/g, at the termination of the exposure. Bioaccumulation measured in terms of fluorescence or in terms of the concentration of specific aromatic targets, increased with dosage. Accumulation of hydrocarbons was observed in muscle tissue (0.22 g/g, dry weight), when concentration of the sum of 27 polycyclic aromatic compounds (PAC) in sediments was of 0.65 g/g (E-50), at the end of the 4-month period. Of the 27 parental and alkylated polycyclic aromatic compounds analyzed, alkylated naphthalenes predominated in muscle (90–100%) and in sediments (30–60%). Bioaccumulation factors were derived for 13 compounds detected in muscle, at the three higher exposures. Liver concentrations (fluorescence) were higher than in muscle, but did not display a noticeable dose-response. Several alkylbenzenes, a C-2 biphenyl and C-4 acenaphthene were also detected in muscle extracts. The development of dose-response relationships for polycyclic aromatic hydrocarbons (PAH) present in sediment, in relation to bioaccumulation in flatfish, is of major interest for evaluating the environmental effects of oil contamination.  相似文献   

2.
This research investigated the accumulation of polycyclic aromatic hydrocarbons (PAHs) by Chironomus riparius from sediments and transfer of these contaminants to bluegill, Lepomis macrochirus. Experiments were conducted in laboratory microcosms containing sediments spiked with either benzo[a]pyrene (BAP) or fluoranthene (FLU). Chironomids rapidly accumulated PAHs from sediments. Concentrations of BAP and FLU in chironomids increased with sediment concentration; however, FLU accumulated to a much greater extent. At sediment concentrations ranging from 47 to 4,040 g/kg, levels of FLU in chironomids ranged from below detection to 181,000 g/kg. In contrast, the maximum concentration of BAP measured in chironomids at similar sediment levels was 6,030 g/kg. Levels of FLU and BAP in bluegill that were fed contaminated chironomids were generally low, indicating either low uptake or rapid metabolism of these compounds.Bioturbation of sediments by chironomids decreased water clarity and released sediment-associated BAP to overlying water. BAP in water and in C. riparius increased significantly with chironomid density. In experiments where bluegill were exposed to BAP from water, direct contact with sediments, and chironomids, each source contributed to total body burden. The results of the experiments indicated that PAHs in sediments may be mobilized and made available to benthic invertebrates and fish.  相似文献   

3.
When Hurricane Katrina struck the U.S. Gulf Coast, levees surrounding New Orleans, Louisiana, USA, were breached, leading to widespread flooding of the city and potential contamination from industrial spills, residential sources, and redistribution of pre-existing pollutants. We chemically characterized sediment samples from five New Orleans locations and used early development and mutagenesis in Japanese medaka (Oryzias latipes) as metrics of the toxic effects of these sediments. Sediment samples were analyzed for organohalogen pesticides, polycyclic aromatic hydrocarbons, polychlorinated biphenyls, and metals. One month after Hurricane Katrina, four of the five sites had unsafe concentrations of arsenic and one or more pesticides, pesticide metabolites, or polycyclic aromatic hydrocarbons. Medaka embryonic mortality and time to hatching both increased during exposure to aqueous extracts of sediments, with the greatest toxicity observed for the most heavily contaminated sediment. Exposure to sediment extracts did not, however, result in significantly elevated rates of mutagenesis. When the most contaminated site was resampled 4.5 months later, the sediment had lower contaminant concentrations and fewer deleterious effects on medaka development. Using the medaka bioassay, therefore, we demonstrate toxic effects of post-Hurricane Katrina sediments immediately following the storm, with some amelioration over time of contaminant concentrations and their negative biological effects.  相似文献   

4.
To evaluate the toxic effects of sublethal concentrations of the fungicide triphenyltinacetate (TPTAc), a prolonged toxicity study was made on rainbow trout (Oncorhynchus mykiss). Fish were exposed to TPTAc concentrations ranging from 1 to 6 g TPTAc/L for 28 and 18 days, respectively, using a flow-through exposure system. Hematological findings included an increase of the total number of erythrocytes and an elevated incidence of erythrocyte degradation stages at 4 g TPTAc/L and higher. The hemoglobin content and the packed-cell volume increased as well at 4 and 1 g TPTAc/L. Whereas the total number of leucocytes increased in fish exposed to 1 g TPTAc/L, the number of leucocytes tended to decrease at higher concentrations. The percentage of lymphocytes within the differential blood cell count decreased. The histopathological examination of TPTAc-exposed fish showed a dose-related lymphocytic depletion of the spleen, accompanied by a proliferation of reticuloendothelial cells and an increased erythrophagia even at the lowest TPTAc concentration. In severe cases, cell necrosis was evident. In liver tissue, a depletion of the glycogen deposits within the hepatocytes could be detected in fish exposed to 4 and 6 g TPTAc/L. The analysis of the phenyltin compounds within various organs of fish by HRGC-FPD revealed remarkable concentrations of triphenyltin of up to 16.1 g/g with the following order of residue levels: liver > kidney > spleen > gills > muscle. Di- and monophenyltin were found only in traces of 1–109 ng/g in these organs. The present study indicates that TPTAc negatively affects rainbow trout in a concentration range that might be present in aquatic environments.  相似文献   

5.
Twenty water samples and 18 underlying sediment samples were collected near effluent discharges along 30 km of a surface stream, Degh Nala, Pakistan, which receives effluents from two major industrial areas. Water quality parameters were very poor, except for reference samples collected upstream from the industrial areas and from a freshwater canal into which the Nala flows. Mercury (Hg) concentrations were extremely high in waters (up to 72 mg/L) and sediments (up to 887 g/g) from the upper reaches, and minor influxes from other sites maintained Hg at alarming levels. Concentrations of DDT (1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane) and its metabolites were greater than 1.0 g/g in two sediment samples. The acute toxicity of water samples to the freshwater planarian, Dugesia dorotocephala, was generally consistent with degree of contamination.  相似文献   

6.
Chemical exposure of assemblers handling creosote-impregnated wood and of a single worker chiselling coal tar pitch layer was assessed by measuring airborne naphthalene and various polycyclic aromatic hydrocarbons (PAHs), and by measurement of urinary excretion of 1-naphthol and 1-pyrenol. The sum concentration of PAHs and of 4–6 aromatic ring-containing PAHs were high, 440 g/m3 and 290 g/m3, respectively, when chiselling. In the assembler's workplace, the PAH concentrations were about 1/50 of this value. Regarding airborne naphthalene concentrations the situation was reversed (assemblers, 1000 g/m3; chiseller, 160 g/m3). Correspondingly, the assemblers' urinary 1-napthol concentrations were 15–20 times higher than those of the chiseller. The urinary 1-pyrenol concentration of the chiseller was 2–4 times higher than among the assemblers. As the estimated pyrene inhalation doses among the assemblers could account for only about 2%–25% of the 24-h pyrenol excretion in urine, the skin was presumably the main route of uptake. For an assessment of the exposure to PAHs, air measurements, monitoring of metabolites in urine and preferably also data on the composition of the skin-contaminating product are needed.  相似文献   

7.
The effects of dieldrin in food organisms and commercial feed on growth and bioaccumulation were determined in mallard ducklings (Anas platyrhynchos). Dieldrin-fed crickets, mealworms and annelid worms, and dieldrin-spiked commercial feed, were fed to mallard ducklings for 8 days. Mean measured food concentrations (animals plus feed) of <0.2, 2.6, 26.2, and 49.3 g/g dieldrin did not affect growth after 14 days. Tissue dieldrin concentrations (g/g wet wt) increased rapidly: up to 80.7 (lipid), 30.1 (skin), 4.1 (liver), 1.8 (muscle), and 1.6 (brain) g/g. Dieldrin concentrations in tissues were up to 3.7 times greater than in the test diets.  相似文献   

8.
Conversion of bottomland hardwood forests agricultural land has reduced habitat and water quality in many lakes in the floodplain of the lower Mississippi River. The objectives of this study were to ascertain current contaminant residue concentrations in fish and sediment from lakes in the Atchafalaya River Basin and to determine the influence of overflow and agricultural land use on contaminant levels. Fish and sediment samples were collected from eight lakes that differed in overflow (no overflow, headwater overflow, backwater overflow) and land-use characteristics (presence or absence of agricultural land). Residue analysis of 24 sediment and 82 fish samples collected from the study lakes showed that contaminant residues were uniformly low. Total DDT concentrations, consisting mainly of DDE, were found in 98% of the fish samples and generally were the highest residues though they rarely exceeded 0.50 g/g. Dieldrin, -BHC and -BHC, in concentrations rarely exceeding 0.05 g/g, were detected in about 50% of the fish samples. Total organochlorine pesticide and PCB residues were less than 2.00 g/g in all fish from all lakes, except for a 3.46 g/g total in spotted gar (Lepisosteus oculatus) from one lake. Sediments were free from pesticide residues except for occasional traces (0.01 g/g) of -BHC. Metal residue concentrations in fish and sediment samples were typical of uncontaminated areas. Lake systems in the Atchafalaya River Basin appeared to be relatively uncontaminated by agricultural pesticides, but metal and organic residues in fish were similar from lakes with the same land-use and overflow characteristics.  相似文献   

9.
Summary The objective of the study was to assess whether moderate occupational exposure to lead may be associated with early changes in potential target organs (thyroid, testes, kidney, autonomic nervous system). Workers exposed to lead in a lead acid battery factory (n = 98; mean blood lead 51 g/dl, range 40–75 g/dl) and 85 control workers were examined. None of the indicators of kidney function (in urine: retinol-binding protein, 2-microglobulin, albumin,N-acetyl--d-glucosaminidase; in serum: creatinine, 2-microglobulin), endocrine function (follicle-stimulating hormone, luteinizing hormone, thyroid-stimulating hormone, thyroxine, triiodothyronine) and autonomic nervous system (R-R interval variations on the electrocardiogram) were correlated with lead exposure (blood lead or duration of exposure) or showed significantly different mean values between the exposed group and controls. These results and an assessment of the published data suggest that compliance with the Directive of the Council of the European Communities on lead exposure (health surveillance in workers whose lead in blood exceeds 40 g/dl and removal from exposure when blood lead exceeds 70–80 g/dl) would prevent the occurrence of significant biological changes in the majority of lead-exposed workers.  相似文献   

10.
Lead poisoning of waterfowl has been reported for decades in the Coeur dAlene River Basin in Idaho as a result of the ingestion of lead-contaminated sediments. We conducted a study to determine whether the addition of phosphoric acid to sediments would reduce the bioavailability of lead to mallards (Anas platyrhynchos). When sediments were amended with 1% phosphorus under laboratory conditions, and diets containing 12% amended sediment were fed to mallards, reductions in tissue lead were 43% in blood, 41% in liver, and 59% in kidney with sediment containing about 4,520 g/g lead on a dry-weight basis and 41, 30, and 57% with sediment containing about 6,990 g/g lead. When sediments were treated with phosphorus and left to age for about 5 months in the field, reductions in lead were 56% in blood, 54% in liver, and 66% in kidney at one site with about 5,390 g/g lead and 64, 57, and 77% at a second site with about 6,990 g/g lead. In the field, the inability to mix the phosphoric acid uniformly and deeply enough into the sediment may have resulted in more than 1% phosphorus being added to the sediment. Although both lab and field amendments of phosphorus substantially reduced the bioavailability of lead, lead concentrations in the tissues of mallards fed the amended sediments were still above those believed to be harmful to waterfowl. Based on earlier studies of sediment toxicity to waterfowl in the Coeur dAlene River Basin, combined with the results of our amendment study, the addition of phosphoric acid as we used it might only significantly benefit waterfowl where sediments or soils contain less than 1,000–2,000 g/g lead.  相似文献   

11.
Samples of wild rice grains available for sale in Manitoba, Canada contained <0.01–6.2 g/g cadmium, <0.01–6.7 g/g lead, and 1.6–14.4 wg/g copper. Rice originating from Saskatchewan and northern Manitoba contained significantly higher copper concentrations than samples from Ontario and southeastern Manitoba. Larger and heavier grains contained higher lead concentrations per unit weight. Mean content of all three metals per individual grain was exponentially correlated with grain size and weight. Total soluble carbohydrate and soluble protein concentrations were negatively correlated with copper concentrations.  相似文献   

12.
Extracts of soil, dust and air from a National Priorities List Landfill have been found to contain distinct profiles of polychlorinated biphenyls (PCBs). The different extracts show subtle differences in toxicities and the soil extract has been shown to cause both Ah receptor mediated effects and Ah receptor independent effects in immature female rats. Evidence of open burning at the site dictated quantitation of polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) for a more accurate tabulation of dioxin equivalencies. High volume air sampling on XAD-2 resin cartridges captured trace amounts of PCDFs and no detectable PCDDs. Acetone:Hexane (1:1) extracts of soil and dust contained 762 g/ml and 250 g/ml PCDFs, respectively, and less than 10% as much PCDD. Subsequent benzene:methylene chloride (1:1) extracts were enriched in coplanar compounds relative to total PCBs. PCDF:PCB ratios in all extracts were higher than in the rice oils contaminated with heated PCBs in the Yusho and Yu-Cheng incidents. No 2,3,7,8-TCDD was detected, and total PCB + PCDD + PCDF toxic equivalencies were dominated by the high proportions of PCDFs.  相似文献   

13.
Cadmium concentration inNereis virens exposed to sediment spiked with cadmium increased linearly with time, no equilibrium concentration being indicated by 24 days of exposure. The concentration withinN. virens also increased with concentration of Cd in the sediment, and smaller worms accumulated higher amounts per unit weight than larger worms. With exposure to sediment containing 1 to 4 ppm Cd, accumulation rates ranged from 0.018 to 0.037g Cd/g dry wt/hr for 1- to 2-g worms and from 0.014 to 0.024g Cd/g dry wt/hr for 5- to 7-g worms. N. virens exposed to 0.03 to 9.2 ppm Cd in sea water for 14 days had accumulation rates of 0.019 to 2.217g Cd/g dry wt/hr for 1- to 2-g worms and 0.013 to 1.327g Cd/g dry wt/hr for 5- to 7-g worms.There was practically no excretion of cadmium forN. virens with initial concentrations of 5 to 20g Cd/g dry wt during 75 days in clean conditions.Sediment containing 1 and 4 ppm Cd produced concentrations of about 0.03- and 0.1-ppm cd in the overlying water. The accumulation rates from sediment with 1 and 4 ppm Cd are equal to the rates from sea water with 0.03 and 0.1 ppm Cd, respectively, indicating that cadmium uptake byN. virens is primarily from the aqueous phase.  相似文献   

14.
The processes of atrazine (2-chloro-4-[ethylamino]-6-[isopropylamino-]-s-tri-azine) uptake and release in the submersed vascular plant,Potamogeton perfoliatus L., were rapid, approaching equilibrium with the surrounding environment within one hr. The ratio of internal atrazine concentration to external concentration was approximately 10 at the point of maximum photosynthetic inhibition and rapidly increased at lower external atrazine concentrations. The I50 (the concentration inhibiting photosynthesis by 50%) for atrazine in solution was 80 g/L with the maximum observed photosynthetic reduction (87%) at a solution concentration of 650 g/L. Initial photosynthetic recovery ofP. perfoliatus following exposure to atrazine was rapid with oxygen evolution from treated plants (5, 25, and 100 g/L) being statistically indistinguishable from control plants after two hr of atrazine-free wash. However, there was an indication of residual photosynthetic depression in dosed plants, even after a 77 hr recovery period. In Chesapeake Bay, potential long-term exposure of submersed plants to concentrations of atrazine greater than 10 g/L is doubtful so that reduction ofP. perfoliatus photosynthesis under such conditions would be minimal and reversible.  相似文献   

15.
Flow-through early-life-stage (ELS) toxicity tests were conducted with the pesticides aldicarb (Temik®) and fonofos (Dyfonate®) to determine their effect on the survival and growth of fathead minnows. Concentrations of 78g/L of aldicarb and 16g/L of fonofos did not affect survival and growth. However, 156g/L of aldicarb and 33g/L of fonofos were lethal to larval-juvenile exposed for 30 days post-hatch. The maximum acceptable toxicant concentration (MATC) of aldicarb and fonofos for the fathead minnow is estimated to be between 78–156g/L and 16–33g/L, respectively. The corresponding chronic values (geometric mean of MATC values) would be 110g/L and 23g/L. Acute toxicity tests gave 96-hr LC50 values of 1370g aldicarb/L and 1090g fonofos/L. The acute-chronic ratio (96-hr LC50/chronic value) is 12 for aldicarb and 47 for fonofos.  相似文献   

16.
Lead and cadmium levels in blood and deciduous teeth (shed incisors only) of 6-year-old German children were determined in 1991 in a large epidemiological study carried out in rural and urban areas of western Germany (Duisburg, Essen, Gelsenkirchen, Dortmund, Borken) and eastern Germany (Leipzig, Halle, Magdeburg, Osterburg, Gardelegen, Salzwedel). In total, blood lead and cadmium levels of 2311 German children and tooth lead and cadmium levels of 790 German children were analyzed. Blood lead levels were generally low in all study areas with geometric means between 39.3 g/1 and 50.8 g/l in the western German and between 42.3 g/1 and 68.1 g/l in the eastern German study areas. The mean blood lead level of Turkish children (n = 213) living in the western German study areas was 50.1 g/l and thus 5.6 g/1 higher than the overall geometric mean of the western German children. The higher exposure may be explained by a higher oral uptake from food and different living conditions. These children were excluded from multiple regression analysis because they were all living in the western study areas. The mean tooth lead levels ranged between 1.50 and 1.74 g/g in the western and between 1.51 g/g and 2.72 g/g in the eastern study areas. Thus, they show a distribution pattern similar to blood. Blood and tooth lead levels were higher in urban than in rural areas and higher in the eastern German than in the western German study areas. With regard to the blood and tooth cadmium concentrations, no significant differences between the study areas could be found. The mean cadmium levels in blood ranged between 0.12 g/1 and 0.14 g/l and the mean tooth cadmium concentrations between 20.8 ng/g and 27.8 ng/g. Blood and tooth lead and cadmium levels of the eastern and western German children were thus mainly at a relatively low level in all rural and urban study areas. The study demonstrates and confirms that blood and tooth lead levels are influenced by several demographic, social, and environmental variables. The results indicate that there has been a further significant decrease of lead and cadmium exposure in western German children since our last epidemiological study carried out in the same study areas in 1985/1986.  相似文献   

17.
Model coal piles were constructed and leached with distilled water under simulated rainfall conditions. The piles were composed of one of four coals: two of high sulfur content (Illinois #6 and Western Kentucky), one of low sulfur content (Montana Nerco), and one of variable sulfur content (Texas lignite). There were nine rainfall simulations spaced 15 days apart. The runoffs were collected, extracted at acid and base pH, and analyzed by capillary column gas chromatography/mass spectrometry (GC/MS). Also, an extreme case was simulated by stir-extracting a coal with three different organic solvents in an acid and base medium, and the extracts were analyzed by GC/MS. The most common organic compound identified in any extract was phenanthrene. Aliphatic hydrocarbons and polycyclic aromatic hydrocarbons (PAHs), and methyl and ethyl substituted PAHs were also identified. The concentration of most of the compounds did not exceed 50 g/L. The concentrations of compounds in the extreme case simulations ranged from below detection (< 1 /L) up to 107 /L. The data demonstrated that runoffs from coal piles may contain numerous organic compounds including many PAHs.  相似文献   

18.
Chlorophenols are transformedin vitro to polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/ Fs) by peroxidase-catalyzed oxidations. This is demonstrated with bovine lactoperoxidase as well as horseradish peroxidase, and with 3,4,5- and 2,4,5-trichlorophenol (TrCP). The yield of total PCDD/Fs with lactoperoxidase was 11 g per g 345-TrCP and 10 g per g 245-TrCP, of which 2,3,7,8-substituted PCDD/Fs constituted 8.5 and 2.2 g/g, respectively, corresponding to 0.85 and 1.2 g/g of Nordic TCDD-equivalents.  相似文献   

19.
Acute toxicity tests were conducted to compare estimates of toxicity, as modified by salinity and temperature, based on response surface techniques with those derived using conventional test methods, and to compare effect of a single episodic exposure to cadmium as a function of salinity with that of continuous exposure.Regression analysis indicated that mortality following continuous 96-hr exposure is related to linear and quadratic effects of salinity and cadmium at 20°C, and to the linear and quadratic effects of cadmium only at 25°C. LC50s decreased with increases in temperature and decreases in salinity. Based on the regression model developed, 96-hr LC50s ranged from 15.5 to 28.0 g Cd/L at 10 and 30% salinities, respectively, at 25°C; and from 47 to 85 g Cd/L at these salinities at 20°C. Trimmed Spearman-Karber method used in analysis of a second data set yielded estimates at 20°C and 25°C comparable to those of multiple regression analysis. At 30°C, the 96-hr LC50 was <11 g/L.The relationship of median tolerance to cadmium concentration and exposure time was related to the interaction of both factors and independent of salinity between 10 and 30% at 25°C. The quadratic model predicts mortality of 50% following exposures of <12 hr to the highest concentration examined (92 g/L). For exposure durations of 16 and 24 hr, 50% mortality is predicted to occur at 78 and 56 g/Cd/L, respectively.Environmental Research Laboratory-Narragansett, RI, Contribution #950.  相似文献   

20.
Effects of tributyltin (TBT) on survival, growth, morphometry, and RNA-DNA ratio in larval striped bass(Morone saxatilis) were assessed in three experiments. In Experiment I, 13 day old larvae were exposed to 0, 0.067, 0.766, or 2.284 g TBT/L for 6 days. All larvae exposed to 2.284 /L died by day 5; exposure to 0.766 g/L significantly reduced survival relative to controls (59.8% vs. 81.8%). Significant, concentration-dependent decreases in body depth occurred in larvae exposed to 0.067 and 0.766 g/L. In Experiment II, all 16 day old larvae exposed to 1.498 g/L died by day 6. Survival, weight, and morphometry parameters were not significantly different in larvae exposed to 0, 0.052, or 0.444 g/L for 7 days. In Experiment III, survival was similar in 21 day old larvae exposed to 0, 0.055, 0.218, or 0.514 /L for 7 days. Notochord length and dry weight decreased significantly in larvae exposed to 0.514 g/L. Weight and morphometry parameters were more sensitive indicators of sublethal stress than RNA-DNA ratio. Maximum TBT concentrations reported in Chesapeake Bay marinas are likely to cause increased larval mortality. Longer-term studies are needed to assess effects at <0.050 g/L, which may be more representative of habitat conditions.  相似文献   

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