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1.
Concentrations of copper in water rose rapidly following the introduction of boats to a new marina in San Diego Bay. Two months after the marina reached half its capacity, a majority of water samples exceeded chronic and acute criteria for dissolved copper, and copper concentrations in several samples exceeded the highest concentrations observed in another marina that has been listed as an impaired water body. A box model suggested that a small fraction of the leached copper was sequestered in sediment. Copper concentrations in water entering the marina from the bay was more than half the chronic concentration limit, so only 50% of marina boat capacity could be accommodated without exceeding the chronic criterion more than 50% of the time. Copper concentrations in water may increase rapidly following boat introduction in small marinas, but could return to pre-introduction levels by controlling boat numbers or reducing use of copper-based paints.  相似文献   

2.
The bioavailability and toxicity of copper (Cu) in Shelter Island Yacht Basin (SIYB), San Diego, CA, USA, was assessed with simultaneous toxicological, chemical, and modeling approaches. Toxicological measurements included laboratory toxicity testing with Mytilus galloprovincialis (Mediterranean mussel) embryos added to both site water (ambient) and site water spiked with multiple Cu concentrations. Chemical assessment of ambient samples included total and dissolved Cu concentrations, and Cu complexation capacity measurements. Modeling was based on chemical speciation and predictions of bioavailability and toxicity using a marine Biotic Ligand Model (BLM). Cumulatively, these methods assessed the natural buffering capacity of Cu in SIYB during singular wet and dry season sampling events. Overall, the three approaches suggested negligible bioavailability, and isolated observed or predicted toxicity, despite an observed gradient of increasing Cu concentration, both horizontally and vertically within the water body, exceeding current water quality criteria for saltwater.  相似文献   

3.
Polycyclic aromatic hydrocarbons (PAHs) have garnered much attention due to their bioaccumulation, carcinogenic properties, and persistence in the environment. Investigation of the spatial distribution, composition, and sources of PAHs in sediments of three recreational marinas in San Diego Bay, California revealed significant differences among marinas, with concentrations in one site exceeding 16,000 ng g? 1. ‘Hotspots’ of PAH concentration suggest an association with stormwater outfalls draining into the basins. High-molecular weight PAHs (4–6 rings) were dominant (> 86%); the average percentage of potentially carcinogenic PAHs was high in all sites (61.4–70%) but ecotoxicological risks varied among marinas. Highly toxic benzo(a)pyrene (BaP) was the main contributor (> 90%) to the total toxic equivalent quantity (TEQ) in marinas. PAHs in San Diego Bay marina sediments appear to be derived largely from pyrogenic sources, potentially from combustion products that reach the basins by aerial deposition and stormwater drainage from nearby streets and parking lots.  相似文献   

4.
The use of copper in antifouling paints has increased in the UK in the last 20 years as TBT and several other organic biocides have been phased out. To assess the probable impact of copper on estuarine systems a survey was undertaken to measure the different fractions of copper present in the water column at current usage. The different fractions measured were; labile copper, (LCu) considered as both the free copper ions and inorganically bound copper, the total dissolved copper (TDCu) present, and the difference between them taken as the organically bound likely non-toxic copper fraction. The survey considered sites with different levels of boat use, namely marinas, harbours and estuaries, differing physical parameters of suspended and dissolved organic matter, different seasons of the year and different depths in the water column all of which control speciation behaviour. Suspended particulate matter (SPM) values were measured at all sites and increased from West to East coast locations (5.7-34.4 mg/l). Dissolved organic matter (DOM) values ranged from 0.58 to 2.2mg/l C. The total dissolved copper concentrations ranged from 0.30 to 6.68 microg/l, with labile fraction ranging from 0.02 to 2.69 microg/l, and most labile copper concentrations below 1 microg/l. None of the yearly mean copper measurements exceeded the 76/464/EEC EQS of 5 microg/l. Of the 306 measurements, only one dissolved copper value in one season was above 5 microg/l. This ratio of labile to total copper was between 10 and 30%. The results from this survey suggest that if toxicity of copper is due to the labile fraction then using the total dissolved copper concentrations as an indicator of impact overestimate the risk by a factor of four times.  相似文献   

5.
Differences in sediment contaminant concentrations within two marinas and adjacent to the marinas in St. Thomas, US Virgin Islands were compared to calculate the portion of those contaminants due to marina activities. In marina 1 (containing no vessel maintenance areas, but with a fuel dock) 88% of observed PAHs and 0% of metals were attributed to marina activities. In the marina/boatyard complex, 46% of PAHs and 89% of metals were attributed to marina sources. The distance from storm drain discharges, and sediment characteristics play a greater role in the distribution and fate of pollutants than do activities associated with a given marina station. The data also provided some evidence that the protection marinas offer to vessels from wind, currents, and waves may concentrate contaminants.  相似文献   

6.
Two US Virgin Islands marinas were examined for potential metal impacts by comparing sediment chemistry data with two sediment quality guideline (SQG) values: the ratio of simultaneously extractable metals to acid volatile sulfides (SEM-AVS), and effects range-low and -mean (ERL-ERM) values. ERL-ERMs predicted the marina/boatyard complex (IBY: 2118 microg/g dry weight total metals, two exceeded ERMs) would have greater impacts than the marina with no boatyard (CBM: 231 microg/g dry weight total metals, no ERMs exceeded). The AVS-SEM method predicted IBY would have fewer effects due to high AVS-forming metal sulfide complexes, reducing trace metal bioavailability. These contradictory predictions demonstrate the importance of validating the results of either of these methods with other toxicity measures before making any management or regulatory decisions regarding boating and marina impacts. This is especially important in non-temperate areas where sediment quality guidelines have not been validated.  相似文献   

7.
The objective of this study was to use a probabilistic approach to determine the ecological risk of Irgarol and its major metabolite (GS26575) in coastal California marinas and reference areas by using monitoring data collected during the summer of 2006. Distributions of environmental exposure data were compared with the distribution of plant species response data from laboratory toxicity studies and the no observed effect concentration (NOEC) from a microcosm study to quantify the likelihood and significance of ecological risk. Toxicity testing indicates plants are much more sensitive to Irgarol than animals; therefore, the conservative effects benchmark used to characterize risk was the plant 10th centile for both Irgarol (193 ng/L) and GS26575 (5622 ng/L). In addition, the microcosm NOEC of 323 ng/L was also used to characterize risk. Irgarol concentrations from 15 California marinas ranged from 1.45 to 339 ng/L while GS26575 concentrations ranged from non-detected to 74 ng/L. The probability of exceeding the Irgarol plant 10th centile of 193 ng/L for 15 marinas sampled in coastal California in 2006 was 7.3% while the probability of exceeding the microcosm NOEC of 323 ng/L was even lower (5.5%). In general, this probability of exceedence for either effects benchmark and subsequent ecological risk is considered to be low for these marinas as only one marina (Kings Harbor marina in Redondo Beach) had measured concentrations of Irgarol exceeding 193 ng/L. Irgarol exposure is concentrated within marinas and ecological risk from Irgarol exposure in adjoining reference areas was judged to be very low. Ecological risk from GS26575 exposure was also low in both marina and reference areas in California.  相似文献   

8.
At present, there is a very limited information on the levels and distribution of dissolved metals in Manila Bay. In this study, the horizontal and vertical distribution of operationally defined species (labile, bound and total) of dissolved copper (Cu), cadmium (Cd) and zinc (Zn) were determined using differential pulse anodic and cathodic stripping voltammetry in water samples obtained from 18 stations in November 1998. In addition, the 24-h variability in the concentrations of these species at different depths in the water column was determined. These measurements were complemented by the determination of temperature, salinity, dissolved oxygen, chlorophyll a, particulate organic carbon and nutrients. Results showed that more than 50% of total dissolved copper and cadmium were labile while 50% of total dissolved zinc was organically bound. Vertical profiles showed that Cu, Cd and Zn concentrations were generally high at the surface. Zinc and cadmium were characterised by the presence of a mid-depth minimum while copper did not show any clear vertical trend.

Dissolved Cu concentrations during the spatial and diurnal samplings ranged from 0.32 to 6.95 nM and 1.52 to 45.65 nM, respectively. For Cd, the concentrations in 18 stations ranged from 0.05 to 2.92 nM, and from 0.03 to 2.42 nM over a 24-h period. Zn concentrations ranged from 2.48 to 147.43 nM and 2.87 to 88.27 nM during the spatial and diurnal samplings, respectively. The large variation in the concentration of Cu, Cd and Zn in the bay was observed to be associated with the presence of a large vertical density gradient in the water column, which appeared to limit the exchange of materials between the surface and bottom waters. Elevated levels of these metals near point sources suggest anthropogenic inputs in the bay.  相似文献   


9.
The aim of this study was to assess trace metal contamination of drinking water in the Pearl Valley, Azad Jammu and Kashmir (Pakistan). The objectives were to determine physical properties and the dissolved concentration of five trace metals, i. e., lead, copper, nickel, zinc, and manganese, in drinking water samples collected from various sites of municipal water supply, natural water springs and wells in the valley. Concentrations of the metals in the water samples were determined by flame atomic absorption spectrometry. Results showed physical parameters, i. e., appearance, taste and odor within acceptable limits and pH was between 5.5 and 7.0. The observed concentrations of the metals varied between sources of water samples and between sampling sites. Maximum dissolved concentration observed was 4.7 mg/L for Pb and Mn, 4.6 mg/L for Zn, 2.9 mg/L for Ni and 2.8 mg/L for Cu. The observed concentrations of the metals were compared with the World Health Organization's guideline values for drinking water. Overall, the quality of water samples taken from the water springs at Mutyal Mara and Bonjosa was good; however, the water quality was unsuitable for drinking in Kiraki, Kharick, and Pothi Bala localities particularly. Finally, the authors discuss possible causes for increased concentrations of the trace metals in drinking water in the study area.  相似文献   

10.
Despite the regulatory mandate to maintain “natural water quality”, there are ?271 storm drain discharges that potentially threaten the 14 designated marine water quality protected areas in Southern California called Areas of Special Biological Significance (ASBS). After sampling 35 site-events, the geomean concentrations of total suspended solids, nutrients, total and dissolved trace metals, and polycyclic aromatic hydrocarbons in the ocean following storm events were similar between reference drainages and ASBS discharge sites. Concentrations of chlorinated hydrocarbons were nondetectable and no post-storm sample exhibited significant toxicity to the endemic purple sea urchin (Strongylocentrotus purpuratus) near ASBS discharge sites. A reference-based threshold was developed and, despite the similarities in average concentrations, there were some individual ASBS discharge sites that were greater than reference background. Cumulatively across all ASBS, the constituents that were most frequently greater than the reference-based threshold were nutrients and general constituents, followed by dissolved and total trace metals.  相似文献   

11.
Transplanted mussels and diffusive gradients in thin films (DGT) were used to assess levels of cadmium, copper, lead and zinc at four sites situated inside and outside of two enclosed marinas, near Melbourne, Australia. Mussels accumulated all metals except cadmium. Over one year, there were large temporal differences in tissue metal levels in mussels, but differences between sites were only apparent for copper and lead. DGT showed temporal differences of the same kind as those seen in the mussels, but appeared to have more power to discriminate between sites. DGT found higher copper levels inside marinas than outside, and high levels of zinc were found inside one marina. Levels of copper and zinc were high enough to be of environmental concern for one site. The effect of fouling on DGT measurements will have to be quantified, or avoided by the use of multiple short-term exposures, if the technique is to become a widespread in situ monitoring tool.  相似文献   

12.
A monthly sampling programme for dibutyltin (DBT), tributyltin (TBT) and tetrabutyltin (TTBT) was initiated for a period of one year (July 1985–June 1986) in the Maryland waters of Chesapeake Bay. Concentrations of the above butyltin species were evaluated in the microlayer and water column of eight sampling stations representing two small and two large marinas, a large harbour, two major river systems and a heavily used shipping channel. DBT concentrations in the microlayer were generally higher in the four marinas when compared with the other stations. The highest DBT concentration reported in the microlayer was 1156 ng l−1. Mean microlayer TBT concentrations ranged from 54–310 ng l−1 in the four marinas. Three TBT concentrations ranging from 1049–1171 ng l−1 were reported in the microlayer of the marinas. TBT concentrations of 41 and 29 mg l−1 were detected in the microlayer of a heavily used shipping channel (C & D Canal) during May and June. TTBT concentrations were not detected in the microlayer at most stations during the 12 month sampling period.Mean DBT concentrations in the water column ranged from 23–145 ng l−1 in the four marinas. DBT concentrations in the water column of the other stations were < 35 ng l−1. Mean water column concentrations of TBT ranged from 51–408 ng l−1 in all four marinas. Peak concentrations of TBT were reported in May and June for the various marinas. The highest TBT concentration reported in the water column was 998 ng l−1. TBT concentrations of 20–24 ng l−1 were reported in one of the river systems (Potomac River). TTBT concentrations were not detected in the water column at most of the stations.  相似文献   

13.
The objectives of this study were to measure: (1) Irgarol and GS26575 (major metabolite) during the peak 2004 boating season at selected marinas and reference areas in the Carolinian Zoogeographic Province of the Eastern United States; (2) Irgarol and GS26575 at selected stations during the summer months in the Back Creek/Severn River area in Maryland in 2003 and 2004; and (3) structural and functional characteristics of resident phytoplankton communities concurrently with Irgarol and GS26575 monitoring in Back Creek/Severn River area. Irgarol concentrations from 14 marinas in the Carolinian Province ranged from non-detectable (<1 ng/L) to 85 ng/L; concentrations were less than 16 ng/L at all reference sites. The probability of exceeding the plant 10th centile for Irgarol (251 ng/L) was less than 0.6% for all marinas and 0.01% for all reference areas. These data suggest low ecological risk from Irgarol exposure for both marina and reference areas in the Carolinian Province. Irgarol concentrations ranged from 5 ng/L at the Severn River reference site to 1,816 ng/L in Port Annapolis marina during the two year study. Ecological risk from Irgarol exposure was high for the Port Annapolis marina sites based on a probability of exceeding the plant 10th centile. However, risk was low for Severn River and Severn River reference sites. Functional and structural measures of resident phytoplankton communities in the Back Creek and Severn River did not suggest that these target species are impaired in the Port Annapolis marina area where probabilistic analysis predicted adverse effects from Irgarol exposure.  相似文献   

14.
A survey on the metal concentrations (As, Ba, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Sr, V, Zn) in beach water and sediments is reported from the tourist destination of Acapulco city on the Pacific coast of Mexico. The concentration of dissolved trace metals (DTMs) in beach water and acid leachable trace metals (ALTMs) in sediments indicated that they are anthropogenic in nature due to the increased tourist activities in the crowded beach locations. The statistical analysis indicates Fe and Mn play a major role as metal scavengers in both the medium (water and sediment) and the higher value of other metals is site specific in the study area, indicating that they are transported from the local area. Comparison results suggest that the beach water quality has deteriorated more than the sediments and special care needs to be taken to restore the beach quality.  相似文献   

15.
Water samples from the Humber Estuary adjacent to a discharge of metal refinery effluent were found to have high dissolved metal concentrations and low pH. Bacterial activities and concentrations of viable bacteria were low, indicating inhibition of bacteria and reduction in self-purification. Toxicity tests demonstrated that acid conditions and copper and arsenic amongst metals probably contributed to bacterial inhibition.  相似文献   

16.
Irgarol and its major metabolite (GS26575) were measured in Maryland waters of Chesapeake Bay: (1) in and near 10 marinas, a mainstem Bay site and two Severn River locations during a general survey in July and December of 2002; (2) at various sites in the Port Annapolis Marina and the Severn River area during March of 2002 before the boating season began; and (3) during July (peak boating season) in the same Port Annapolis Marina and Severn River sites area during both an ebb and flood tide. Irgarol concentrations ranged from 1.82 ng/l at the mid-Bay site to 585 ng/l in Port Annapolis marina during the July and December general survey. An Irgarol 90th centile of 239 ng/l was reported for the 10 marina sites, two Severn River sites and one mainstem site sampled during the general survey conducted in July and December. Temporal analysis of all pooled data showed that 90th centiles were over seven times higher in July when compared to December. A comparison of Irgarol concentrations at 12 sites in the Port Annapolis marina and Severn River area during both an ebb and flood tide in July showed no consistent trend with tidal cycle by site although significant reductions in concentrations were reported with distance from the three Port Annapolis marina sites. Ecological risk from Irgarol exposure was judged to be low for most Chesapeake Bay sites sampled. Possible exceptions were Port Annapolis marina, Severn River sites in close proximity to this marina and Chesapeake Harbor marina where Irgarol concentrations exceeded a conservative effects threshold during the peak boating season in July. Ecological risk from GS26575 exposure was low for all sites.  相似文献   

17.
Two sampling cruises conducted in the Seine estuary (France) under low-water and flood conditions produced high resolution profiles for dissolved cadmium, lead, copper, zinc and nickel concentrations versus salinity. The distribution of dissolved trace metals differed depending on hydrologic conditions, partly because of the dilution of upstream inputs during flood periods. Daily fluxes of these dissolved trace metals were estimated for the two sampling periods (September 1994 and February 1995) by extrapolating the dilution lines observed in higher salinity waters to salinity=0 and then multiplying the effective freshwater concentrations thus obtained by the corresponding freshwater flow. Several procedures were subsequently applied to deduce each daily flux for the year studied from data for these two periods. A consensus was found among these procedures, allowing the determination of net fluxes of dissolved trace metals with a precision of 20–35%. The net fluxes thus estimated were 4 T yr−1 for Cd, 4 T yr−1 for Pb, 40 T yr−1 for Cu, 130 T yr−1 for Zn and 50 T yr−1 for Ni.  相似文献   

18.
Several studies have provided evidence for the enrichment of trace elements in coastal waters, particularly for copper. These enrichments have been attributed to diffusion from continental shelf sediments and to an influx of river water. We attempted to resolve between these sources by undertaking an extensive suite of measurements of trace metals (Cu, Ni, Cd), 226Ra and 228Ra in the surface waters of the Gulf of Mexico, along with trace metal profiles at 6 stations (April 1981 and December 1982). These data establish that enrichments of copper, nickel and cadmium occur in the shallow waters of the Gulf of Mexico. On the Mississippi continental shelf, high trace element concentrations (Cu, Ni: ~ 9 nmol/kg; Cd: ~ 200 pmol/kg) in lower-salinity waters (26‰) are similar to those observed in the Mississippi plume at the same salinity. This evidence suggests a river water source. On the other hand, trace element enrichments are also observed in the northern Gulf (Cu: +0.4 nmol/kg; Ni: +0.5 nmol/kg; Cd: +20 pmol/kg) which coincide with an increase in 228Ra but are not accompanied by decreased salinity. The excess of evaporation over precipitation in this region makes it possible that this water could be evaporated estuarine water; therefore, hydrographic observations cannot distinguish readily between river and shelf sources. A regional flux balance shows that most of the excess copper in the surface waters of the Florida Current can be supplied by the river-borne dissolved copper flux. Within the uncertainties of such calculations, the continental shelf copper flux must be less than or equal to the river flux.  相似文献   

19.
The artificial mussel (AM), a novel chemical sampling device, has been developed for monitoring dissolved trace metals in marine environments. The AM consists of Chelex-100 suspended in artificial seawater within Perspex tubing and enclosed with semi-permeable polyacrylamide gel at both ends. To validate the field performance of the AM in temperate waters, we deployed AMs alongside transplanted blue mussels Mytilus edulis in coastal environments in Scotland (Holy Loch, Loch Fyne, Loch Striven and Millport) and Iceland (Reykjavikurh?fn, Gufunes, South of thornerney, Hofsvik, Hvalfj?rethur and Sandgerethi) for monitoring trace metals. While uptake patterns of Cd between the AM and M. edulis were highly comparable, discrepancies were found in the accumulation profiles of the other metals (Cu, Cr, Pb and Zn), in particular Zn. Nonetheless, the AMs gave a better resolution to accurately reveal the spatial difference in dissolved metal contamination when compared with M. edulis. AMs complement the use of mussels since AMs indicate dissolved metals in seawater, whereas uptake by mussels indicates a mixture of dissolved and particulate metals. Our results also indicated that historical metal exposure of the transplanted M. edulis could significantly confound their metal concentrations especially when the deployment period was short (i.e. <34d). This study suggested that the AM can overcome problems associated with variable biological attributes and pre-exposure history in the mussel, and provides a standardized and representative time-integrated estimate of dissolved metal concentrations in different marine environments.  相似文献   

20.
Studies into the partitioning of trace metals between the dissolved phase and suspended solids have been performed on two major UK estuaries, the Mersey and the Humber. Aqueous phase trace metal concentrations were determined, along with partitioning data (Kp) determined from both laboratory equilibration experiments and by chemical leaching techniques.

Dissolved trace metals in the Humber essentially exhibited conservative behaviour (or a slight positive deviation). In the Mersey, however, removal of zinc, chromium, and, in particular, copper and cadmium occurred in the low salinity region.

Sequential extraction data gave an indication of the nature of trace metal bindings to suspended sediment, and revealed total extractable trace metals on the Mersey suspended sediment to be a factor of two greater than that found in the Humber. Similarly, partition coefficients in the Mersey were approximately an order of magnitude greater than in the Humber. Chloro-complexation was shown to control the partitioning of cadmium within estuaries. Copper, however, exhibited a distinct trend of increasing Kp with increasing salinity.  相似文献   


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