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1.
The occurrence of three endocrine disrupting compounds, 4-n-nonylphenol, triclosan and bisphenol A, was investigated in different bivalves originating from the Aegean Sea (Greece). The bioconcentration potential of these compounds was studied using the Mediterranean mussel (Mytilus galloprovincialis). Tissue samples were extracted by sonication. Analysis was performed by gas chromatography-mass spectrometry. According to the field survey results, the average concentrations of 4-n-nonylphenol, triclosan and bisphenol A, were 158, 461 and 404 ng g−1 (dry weight), respectively. During 28 days of exposure at 300 ng L−1, the tissue concentrations of compounds were constantly increased. Steady state was not observed up to the end of the experiment. Kinetic bioconcentration factors varied from 1.7 (4-n-nonylphenol and triclosan) to 4.5 L g−1 (bisphenol A). Following exposure, mussels were relocated to clean water for 28 days. This experiment revealed that depuration rates for all of the target compounds were lower than uptake rates. The biological half-lives of each compound ranged between 12 days (triclosan) and 26 days (bisphenol A).  相似文献   

2.
210Po and 210Pb in mussel (Mytilus galloprovincialis) and sediment samples collected at Candarl? Gulf during the period of 2010–2012 are presented and discussed. The activity concentrations of 210Po and 210Pb were measured by means of alpha spectrometry. Activity concentrations of 210Po and 210Pb in mussels are in the ranged of 332 ± 17–776 ± 23 Bq kg−1 dw and 14 ± 1–40 ± 5 Bq kg−1 dw, for sediments the ranges for 52 ± 5–109 ± 8 Bq kg−1 dw and 38 ± 5–92 ± 9 Bq kg−1 dw, respectively. The estimated consequent annual effective ingestion dose due to 210Po and 210Pb from mussel consumption in Candarl? Gulf coastal region were calculated. The highest dose due to 210Po and 210Po were calculated to be 4232 ± 126 μSv and 126 ± 16 μSv, respectively.  相似文献   

3.
Uptake and depuration kinetics of dissolved [14C]C12-6-linear alkylbenzene sulfonate (LAS) were determined in the shrimp Palaemonetes varians using environmentally relevant exposure concentration. The shrimp concentrated LAS from seawater with a mean BCF value of 120 L kg−1 after a 7-day exposure. Uptake biokinetics were best described by a saturation model, with an estimated BCFss, of 159 ± 34 L kg−1, reached after 11.5 days. Shrimp weight influenced significantly BCF value with smaller individuals presenting higher affinity to LAS. To the light of a whole body autoradiography, major accumulation of LAS occurred in the cephalothorax circulatory system (gills, heart, hepatopancreas) and ocular peduncle, but not in the flesh, limiting potential transfer to human consumers. LAS depuration rate constant value of the shrimp was 1.18 ± 0.08 d−1 leading to less than 1% of remaining LAS in its tissues after 8 days of depuration.  相似文献   

4.
Mussels from the Portuguese coast collected during several seasons of the year have shown 210Po and 210Pb body burdens (Bq mussel−1) that increased with mussels’ body size but displayed significant decrease in radionuclide concentrations (Bq kg−1). For example, the increase of mussel size from 2.5 cm to 5.0 cm maximum shell length corresponded in average to a 50% decrease of 210Po activity concentration in soft tissues from 1065 Bq kg−1 (dw) to 540 Bq kg−1 (dw). A similar reduction in concentration was observed for 210Pb. The physiological condition of mussels, relating to fat and glycogen storage, had an effect on radionuclide concentrations, although the total body burden of radionuclide in mussels remained nearly constant throughout the year. These factors may play an important role in data interpretation for environmental monitoring programmes. Besides the mussel size and condition index, due to the inter-individual variation even inside narrow mussel size classes, the sample size, i.e., the number of specimens in one mussel sample is another key factor to be considered when obtaining environmentally representative radionuclide concentrations.  相似文献   

5.
The Hg concentration in seawater and copepod samples collected from the area around hydrothermal vents at Kueishan Island and the adjacent marine environment in northeastern Taiwan were analyzed to study Hg bioaccumulation in copepods living in polluted and clean marine environments. The seawater collected from the hydrothermal vent area had an extremely high concentration of dissolved Hg, 50.6–256 ng l−1. There was slightly higher Hg content in the copepods, 0.08–0.88 μg g−1. The dissolved Hg concentration in the hydrothermal vent seawater was two to three orders of magnitude higher than that in the adjacent environment. The bioconcentration factor of the studied copepods ranged within 103–106, and showed higher dissolved concentration as the bioconcentration factor was lower. A substantial abundance, but with less copepod diversity was recorded in the seawater around the hydrothermal vent area. Temora turbinata was the species of opportunity under the hydrothermal vent influence.  相似文献   

6.
The determination of activity concentrations of the radioactive elements 238U, 232Th, 40K and 137Cs was performed on grab samples taken from a polluted environment. The samples were sliced into strata from 5 cm depth, dried and ground to sieved through a 170 mesh size prior to the analysis. Activity concentration was quantified using gamma spectroscopy. The results showed that the concentrations of activity in the sediment samples are 177 ± 12.4, 117 ± 11.5, 1085 ± 101.6 and 131 ± 4.8 Bq kg−1 for 238U, 232Th, 40K and 137Cs, respectively. In general, the distribution of activity concentrations along the southern coast of the Caspian Sea area exceeded international limits. The hazard index of the samples was 0.19-0.88, with an average of 0.49. The mean values of radium equivalent activity and dose rate are 176 Bq kg−1 and 63 nGy h−1, respectively.  相似文献   

7.
Matrix bound phosphine (MBP), a kind of chemically reduced phosphorus, has received limited attention in prevailing modeling of the phosphorus biogeochemical cycle. MBP has been found to occur in marine sediments. MBP in the sediments of the Yellow Sea and its coastal areas was measured by gas chromatography from 2004 to 2007. MBP levels in surface sediments were 0.19–38.24 ng kg−1 in the shelf of the Yellow Sea, 0.34–17.15 ng kg−1 in the Jiaozhou Bay, 2.11–71.79 ng kg−1 in the Sanggou Bay and 0.28–319.32 ng kg−1 in the rivers around the Jiaozhou Bay. High levels of MBP occurred in the northern and middle areas of the Yellow Sea. Obvious seasonal variation of MBP was observed in surface sediments of the Sanggou Bay, with the highest MBP level occurring in summer and the lowest in winter. MBP in surface sediments of the inner Jiaozhou Bay was higher than those in the outer region. MBP levels increased with depth in the top 5–10 cm sediments of the Jiaozhou Bay and on the intertidal flats. Environmental factors such as type of sediments, temperature, organic matter and human activity were found to affect the concentrations and distribution of MBP in marine sediments.  相似文献   

8.
The activities of 210Po and 210Pb were determined in commonly consumed seafoods to evaluate the internal exposure and risk to humans residing Kudankulam coast where a mega nuclear power plant is under construction. The concentration of 210Po in seafoods ranged from 1.2 ± 0.7 to 248 ± 8.1 Bq kg−1. Meanwhile, 210Pb ranged between 1.1 ± 0.05 and 14.8 ± 1.6 Bq kg−1. The committed effective dose (CED) due to 210Po and 210Pb varied from 11.04 to 515.6 and 3.93 to 23.5 μSv yr−1, respectively. The lifetime cancer risk for the public due to 210Po was in the range of 3.47 × 10−5-1.62 × 10−3 and it was 4.03 × 10−5-1.96 × 10−4 due to 210Pb. The activity intake, effective dose and cancer risk was found lesser than international guidelines and the seafood intake was considered to be safe for human consumption.  相似文献   

9.
The North-East Atlantic porbeagle (Lamna nasus) population has declined dramatically over the last few decades and is currently classified as ‘Critically Endangered’. As long-lived, apex predators, they may be vulnerable to bioaccumulation of contaminants. In this study organohalogen compounds and trace elements were analysed in 12 specimens caught as incidental bycatch in commercial gillnet fisheries in the Celtic Sea in 2011. Levels of organohalogen contaminants were low or undetectable (summed CB and BDE concentrations 0.04–0.85 mg kg−1 wet weight). A notably high Cd concentration (7.2 mg kg−1 wet weight) was observed in one mature male, whereas the range observed in the other samples was much lower (0.04–0.26 mg kg−1 wet weight). Hg and Pb concentrations were detected only in single animals, at 0.34 and 0.08 mg kg−1 wet weight, respectively. These contaminant levels were low in comparison to other published studies for shark species.  相似文献   

10.
Concentrations of lead were assessed in the sea turtle, Lepidochelys olivacea, from a nesting colony of the Eastern Pacific. Twenty-five female turtles were sampled and a total of 250 eggs were collected during the “arribada” event of the 2005-2006 season. Considering the nesting season, the maternal transfer of lead (Pb) via egg-laying, in terms of metal burden in whole body, was 0.5%. Pb concentrations (in dry weight) in blood (0.95 ± 0.18 μg g−1) and egg samples (yolk, 0.80 ± 0.10 μg g−1; albumen, 1.08 ± 0.20 μg g−1; eggshell, 1.05 ± 0.20 μg g−1) were comparable or even lower than those found in other sea turtles. The isotope ratios (206Pb/207Pb and 206Pb/208Pb) in blood (1.183 ± 0.0006 and 2.452 ± 0.0006, respectively) were comparable to that of natural Pb-bearing bedrock in Mexico (1.188 ± 0.005 and 2.455 ± 0.008, respectively). According to international norms of Pb, the health of this population and its habitats is acceptable for Pb and corresponds to basic levels of a nearly pristine environment.  相似文献   

11.
The first analyses of PAHs in marine sediments within Rijeka Bay started in 1998 at three sampling sites offshore from the petroleum refinery facilities and were extended in 1999 to three more sampling points in front of the repair shipyard within the same east industrial zone. The small Svezanj cove, lying between the shipyard and the petroleum refinery was chosen as the reference point. The concentrations of PAHs were considerably higher in the shipyard environment (average: 3009-6314 μg kg−1 d.w.) in comparison to the petroleum refinery area (average: 279-919 μg kg−1 d.w.), while the PAHs load at reference point was close to the latter level (average: 717 μg kg−1 d.w.). The Phe/Anth and Flo/Py ratios indicate the dominant pyrogenic sources, except for the results from 1999 to 2000 with dominant petrogenic origin at some sites. A declining trend of total PAHs, and consequently toxicity indices was observed at all sites.  相似文献   

12.
The plankton was examined as an indicator of water quality in 14 shrimp Litopenaeus vannamei farms in Brazil in 2003. The ponds were categorized by high stocking density (>30 PL m−2) of phytoplankton, consisting of 51 species with concentrations ranging from 365,218 ± 416,615 cells mL−1 to 1,961,675 ± 3,160,172 cells mL−1. Diatoms contributed to almost 70% of the species number and high densities resulted from Cyanophyta blooms, mainly Pseudanabaena cf limnetica. Forty zooplankton taxa were registered and were essentially composed of typical marine euryhaline species and suspension-feeders. Copepoda dominated (45%) the make-up, followed by Protozoa (18%), Rotifera (12%), and Mollusca (12%) larvae. Zooplankton varied from 972 ± 209 ind m−3 to 4235 ± 2877 ind m−3. Enhanced nutrient input affected plankton density and composition. Diatom and Copepoda dominance was replaced by cyanobacteria, protozoan, and rotifers as nutrient concentrations increased with the cultured period, indicating that plankton structure is affected by eutrophic conditions.  相似文献   

13.
The study aimed to determine the spatial distribution of n-alkanes and polycyclic aromatic hydrocarbons (PAHs) in surface sediments of the Segara Anakan nature reserve and their potential origins using gas chromatography–mass spectrometry. Total alkane concentrations ranged from 3755 to 129,027 μg kg−1, and the concentrations of 16 PAHs ranged from 375 to 29,517 μg kg−1. The ratios of specific n-alkanes (e.g., CPI24–34, WaxCn, and Paq), including a new proposed index, terrestrial–marine discriminant (TMD), as well as the ratios of selected PAHs (e.g., Ant/∑178, Fl/∑202, BaAnt/∑228, and IPyr/∑276), showed that the sources of hydrocarbons in the sediments were generally biogenic, including both terrigenous and marine, with an anthropogenic pyrolytic contribution (petrogenic and biogenic combustion). For the environmental risk assessment, a sediment quality guideline (SQGs) comparison indicated that the station risk levels ranged from low to medium-low, except for R6, which has a greater impact on the ecological risk for marine organisms.  相似文献   

14.
Concentrations of rare earth elements (REE), Y, Th and Sc were recently determined in marine sediments collected using a box corer along two onshore-offshore transects located in the Strait of Sicily (Mediterranean Sea). The REE + Y were enriched in offshore fine-grained sediments where clay minerals are abundant, whereas the REE + Y contents were lower in onshore coarse-grained sediments with high carbonate fractions. Considering this distribution trend, the onshore sediments in front of the southwestern Sicilian coast represent an anomaly with high REE + Y concentrations (mean value 163.4 μg g−1) associated to high Th concentrations (mean value 7.9 μg g−1). Plot of shale-normalized REE + Y data of these coastal sediments showed Middle REE enrichments relative to Light REE and Heavy REE, manifested by a convexity around Sm-Gd-Eu elements. These anomalies in the fractionation patterns of the coastal sediments were attributed to phosphogypsum-contaminated effluents from an industrial plant, located in the southern Sicilian coast.  相似文献   

15.
The metabolic balance between production and respiration in plankton communities of the Gulf of Papua was investigated in May 2004. Water samples taken at 19 stations were allocated to groups on the basis of physico-chemical characteristics. Oxygen consumption and production in flasks incubated in the dark and in the light was determined by micro-Winkler titration. Dark bottle respiration in samples influenced by the estuarine plume averaged 3.09±1.92 (SD) mmol O2 m−3 d−1 and production within surface light bottles averaged 7.63±3.36 (SD)  mmol O2 m−3 d−1. Corresponding values in stations more typical of the central Gulf of Papua were 1.68±1.30 (SD) mmol O2 m−3 d−1 and 1.08±2.25 (SD) mmol O2 m−3 d−1. Despite a shallow (<10 m) euphotic zone within the plume stations, phytoplankton production in the surface layers was sufficiently high to subsidise total water column respiration. Integrating production and respiration over the water column resulted in a calculation of net community production (NCP) of 626±504 (SD) mg C m−2 d−1, and community respiration (CR) of 712±492 mg C m−2 d−1 at the plume stations, with an average P:R ratio of 1.97. In the offshore group NCP was 157±450 (SD) mg C m−2 d−1 and CR was 1620±1576 mg C m−2 d−1. The average P:R ratio was 1.27. Three of the 7 stations allocated to the offshore group were net heterotrophic. In contrast to earlier studies in the area indicating that the Gulf of Papua waters is heterotrophic [Robertson, A.I., Dixon, P., Alongi, D.M., 1998. The influence of fluvial discharge on pelagic production in the Gulf of Papua, Northern Coral Sea. Estuarine, Coastal and Shelf Science 46, 319–331], our data indicate that in May 2004 the Gulf was in positive metabolic balance, but by only ∼120 mg C m−2 d−1. We conclude that waters of the Gulf of Papua under riverine influence are net autotrophic, but that within the central Gulf there is a fine metabolic balance alternating between autotrophy and heterotrophy.  相似文献   

16.
This study is the first to measure the particulate phosphorus, including total inorganic phosphorus (TIP) and organic phosphorus (OP), in size-fractionated atmospheric particles. The results indicate that continental and marine sources are the key controls on the particle-size distribution of phosphorus species. For continental and local anthropogenic sources, both TIP and OP are associated with fine-mode aerosols during the winter and spring, and both are also associated with coarse particles during the summer and autumn. The coarse/fine ratios are low during periods with a non-oceanic source but high at other times, probably because of the biological growing season in the surface waters of the study area. The calculated annual fluxes based on estimates of dual-mode particles are 532±185, 435±172, and 96.8±48.8 μmol m−2 yr−1 for TP, TIP, and OP, respectively. Based on previously published solubility data for particulate phosphorus (34%), we calculated an annual flux of 180±63 μmol m−2 yr−1 for readily soluble particulate phosphorus.  相似文献   

17.
A study was done to determine the concentrations of surfactants on the sea-surface microlayer and in atmospheric aerosols in several coastal areas around the Malaysian peninsula. The concentrations of surfactants from the sea-surface microlayer (collected using rotation drum) and from aerosols (collected using HVS) were analyzed as methylene blue active substances and disulphine blue active substances through the colorimetric method using a UV-vis spectrophotometer. The results of this study showed that the average concentrations of surfactants in the sea-surface microlayer ranged between undetected and 0.36 ± 0.34 μmol L−1 for MBAS and between 0.11 ± 0.02 and 0.21 ± 0.13 μmol L−1 for DBAS. The contribution of surfactants from the sea-surface microlayer to the composition of surfactants in atmospheric aerosols appears to be very minimal and more dominant in fine mode aerosols.  相似文献   

18.
The concentrations and sea-to-air fluxes of dissolved methane (CH4) were investigated in the North Yellow Sea during August 2006, January, April and October 2007. Dissolved CH4 concentrations showed obvious seasonal variation, with maximum values occurring in summer and lowest values occurring in winter. The saturations of dissolved CH4 in surface waters ranged from 78.7% to 1679.7% with an average of 252.4%. The estimated atmospheric CH4 fluxes using the Liss and Merlivat (LM86), and Wanninkhof formulae (W92) were (4.2±4.7), (11.6±10.3), (8.5±12.7) and (0.2±1.0), and (6.9±7.3), (14.6±22.3), (13.8±14.3) and (0.4±1.7) μmol·(m2 d)−1, respectively, for spring, summer, autumn and winter. Based on the average annual atmospheric CH4 flux and the area of the North Yellow Sea, the annual CH4 emission was estimated to be (2.4×10−2–4.2×10−2) Tg a−1, which suggests that the North Yellow Sea was a net source of atmospheric CH4.  相似文献   

19.
Environmental pollution due to heavy metals is having an increased impact on marine wildlife accentuated by anthropogenic changes in the planet including overfishing, agricultural runoff and marine emerging infectious diseases. Sea turtles are considered sentinels of ecological health in marine ecosystems. The objective of this study was to determine baseline concentrations of zinc, cadmium, copper, nickel, selenium, manganese, mercury and lead in blood of 22 clinically healthy, loggerhead turtles (Caretta caretta), captured for several reasons in Puerto López Mateos, Baja California Sur, Mexico. Zinc was the most prevalent metal in blood (41.89 μg g−1), followed by Selenium (10.92 μg g−1). The mean concentration of toxic metal Cadmium was 6.12 μg g−1 and 1.01 μg g−1 respectively. Mean concentrations of metals followed this pattern: Zn > Se > Ni > Cu > Mn > Cd > Pb and Hg. We can conclude that blood is an excellent tissue to measure in relatively non-invasive way baseline values of heavy metals in Caretta caretta.  相似文献   

20.
Seasonal variations in the inorganic carbon system in the Pearl River estuary are examined based on data from five surveys during the spring, summer, fall, and winter seasons. Both total dissolved inorganic carbon (DIC) and total alkalinity (TAlk) values in the freshwater end-members are high in the dry season (>2700 μmol kg−1 for DIC and >2400 μmol kg−1 for TAlk) and substantially lower in the wet season (DIC and TAlk were ∼1000 and 700 μmol kg−1, respectively). Riverine DIC flux and drainage basin weathering rates, however, are significantly higher in the wet season (611×109 mol yr−1 and 13.6×105 mol km−2 yr−1) than in the dry season (237×109 mol yr−1 and 5.3×105 mol km−2 yr−1).  相似文献   

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