Biomonitoring of organochlorine compounds and trace metals along the Eastern Adriatic coast (Croatia) using Mytilus galloprovincialis

The paper presents the results of monitoring trace organic contaminants (17 PCBs and 7 OCPs) and 6 trace metals (Cd, Cr, Cu, Hg, Pb and Zn) in the coastal waters of the eastern Adriatic in 2006 using Mytilus galloprovincialis as indicator species. OCPs were found in all samples (0.07-14.3 ng g⁻¹ d.wt.), while in positive samples concentrations of PCBs ranged between 0.16 and 20.5 ng g⁻¹ d.wt. The α-HCH/γ-HCH and DDE/DDT ratios indicated recent input of γ-HCH and DDT. Spatial distributions of HCB, PCBs, DDTs and Hg were significantly correlated with population density. Although elevated concentrations of all trace metals and organic contaminants were recorded in the densely populated and industrialized areas, overall data point to relatively low level of contamination of the eastern Adriatic coast. Evaluation of the risks to human health associated with consumption of the mussels suggested that there is no health risk for moderate shellfish consumers.     

Gulfwatch: monitoring spatial and temporal patterns of trace metal and organic contaminants in the Gulf of Maine (1991-1997) with the blue mussel, Mytilus edulis L

Gulfwatch, established in 1991, is an international contaminant monitoring program in which the blue mussel, Mytilus edulis, is used as an indicator of the level and extent of contamination in the Gulf of Maine. Since 1991, trace metals, PAHs, PCBs, and OC pesticides have been measured in mussel tissues at 56 sites. The distribution of most metals was relatively uniform throughout the Gulf with the exception of Ag, Pb and Cr. However, the concentration of organic contaminants increased in a north-to-south direction. High concentrations of contaminants were correlated with large human population density and proximity to large rivers. Temporal analysis of five sites revealed that the majority of contaminant concentrations were either unchanged or decreasing. The concentrations of most contaminants were lower than the median of the National Status and Trends (NS & T) Mussel Watch with the exceptions of Cr, Hg, Pb and sigma PCB24. Hg concentrations at > 80% of the Gulfwatch sites exceeded the NS & T median +1 SD. Gulfwatch continues as a primary contaminant monitoring program in the Gulf of Maine.     

The spatial and temporal distribution of heavy metals in sediments of Victoria Harbour, Hong Kong

Victoria Harbour has received substantial loadings of pollutants from industrial and municipal wastewater discharged since the 1950s. Inputs of contaminants have declined dramatically during the last two decades as a result of better controls at the source and improved wastewater treatment facilities. To assess the spatial and temporal changes of metal contaminants in sediments in Victoria Harbour, core and grab sediments were collected. The central harbour areas were generally contaminated with heavy metals. The spatial distribution of trace metals can probably be attributed to the proximity of major urban and industrial discharge points, and to the effect of tidal flushing in the harbour. In the sediment cores, the highest concentrations of trace metals were observed to have accumulated during the 1950s-1980s, corresponding with the period of rapid urban and industrial development in Hong Kong. From the late 1980s, there has been a major decline in the concentrations of trace metals, due to a reduction in industrial activities and to the enactment of wastewater pollution controls in the territory. The Pb isotopic compositions of the sediments revealed the anthropogenic inputs of Pb to the harbour. The (206)Pb/(207)Pb ratios varied from 1.154 to 1.190, which were lower than those of background geological materials in Hong Kong ((206)Pb/(207)Pb: 1.201-1.279). The data also indicated that the Pb in the harbour sediments most likely originated from mixed sources, including the leaded gasoline used in the past and other anthropogenic sources.     

Organochlorine compound and trace metal contaminants in fish near Sydney's ocean outfalls

Sydney's inshore sewage outfalls were significant contributors to organochlorine contamination of inshore sedentary fish such as red morwong. Diversion of the sewage to deepwater outfalls has resulted in marked declines in the concentrations of these compounds in inshore red morwong. Apart from lead, however, similar trends did not occur for concentrations of trace metals. A wide variety of trace metals and organochlorine compounds were found in the flesh and/or livers of a variety of fish species caught at sites associated with the present deepwater ocean outfalls off Sydney. Fish caught at locations remote from Sydney also contained a wide variety of trace metals although organochlorine compounds were usually at lower levels. The mean contaminant levels in all species of offshore fish were generally found to be low when compared to the Australian National Food Authority's Maximum Residue Limit (NFA MRL). No fish analysed was found to have levels of an organochlorine compound above the MRL and no fish was found to have levels of zinc or lead above the MRL. When detected, fish with levels of a trace metal above the MRL appeared to be distributed throughout New South Wales, independent of the deepwater ocean outfalls off Sydney. There is no evidence as yet that the commissioning of the deepwater outfalls has led to an increase in levels of contaminants in the fish examined to the extent that they are of concern relative to the NFA MRLs.     

Dispersion of dissolved trace metals from the Irish Sea into Scottish coastal waters

An investigation has been undertaken into the dispersal of contaminants from the Irish Sea into coastal waters of Scotland via the North Channel. A total of 97 surface samples have been analysed for dissolved copper, cadmium and lead. Salinity and reactive phosphate have also been determined. Evidence is presented to suggest that copper, cadmium and reactive phosphate behave essentially conservatively on mixing into Scottish coastal waters. This behaviour is likened to the dispersal of¹³⁷Cs from the Sellafield nuclear fuel reprocessing plant. It is suggested that this simple mechanism is inadequate to account for the lead distribution. It is proposed that this element is partly taken up by suspended particulates and sediments in the well-mixed turbid waters of the North Channel.It has been demonstrated elsewhere that contaminants from the Irish Sea, such as¹³⁷Cs enter the Firth of Clyde from the North Channel. In the present study North Channel waters are demonstrated to be an important source of trace metals to the Firth of Clyde. At the time of this survey however high concentrations of trace metals were not entering the Firth of Clyde from the North Channel. This is principally attributed to a salinity front associated with the entrance of the Firth which hinders transport across the sill.     

Ecotoxicity assessment of natural attenuation effects at a historical dumping site in the western Baltic Sea

During the late 1950s and early 1960s of the past century, industrial waste material highly enriched in various contaminants (heavy metals, PAHs) was dumped in the inner Mecklenburg Bay, western Baltic Sea. Large-scale shifts in the spatial distribution of heavy metals in surface sediments were mapped by geochemical monitoring in the mid-1980s and 12 years later in 1997. A further study in 2001 was designed to investigate the small-scale spatial distribution of contaminants inside, on top of, and around the historical dumping ground and to examine possible effects to benthic organisms (Arctica islandica, microbiological toxicity tests). The site is located within an area characterized by a discontinuous deposition of fine sediments, but net sedimentation rate of about 3mm/y led ultimately to a gradual coverage of the dumped material. During the first decades after the dumping, about half of the originally dumped material was already spread over the surrounding area as a result of sediment dynamics and re-suspension processes. Recent sediments of the historical dump site are still significantly enriched in heavy metals and PAHs. Microbiological toxicity test results were positive, though uptake of contaminants in mussels was found to deviate only slightly from that of a non-contaminated reference station due to a gradual dilution and decrease in bioavailability of the contaminants.     

The spatial and temporal distribution of heavy metals in sediments of Victoria Harbour,Hong Kong

Victoria Harbour has received substantial loadings of pollutants from industrial and municipal wastewater discharged since the 1950s. Inputs of contaminants have declined dramatically during the last two decades as a result of better controls at the source and improved wastewater treatment facilities. To assess the spatial and temporal changes of metal contaminants in sediments in Victoria Harbour, core and grab sediments were collected. The central harbour areas were generally contaminated with heavy metals. The spatial distribution of trace metals can probably be attributed to the proximity of major urban and industrial discharge points, and to the effect of tidal flushing in the harbour. In the sediment cores, the highest concentrations of trace metals were observed to have accumulated during the 1950s–1980s, corresponding with the period of rapid urban and industrial development in Hong Kong. From the late 1980s, there has been a major decline in the concentrations of trace metals, due to a reduction in industrial activities and to the enactment of wastewater pollution controls in the territory. The Pb isotopic compositions of the sediments revealed the anthropogenic inputs of Pb to the harbour. The ²⁰⁶Pb/²⁰⁷Pb ratios varied from 1.154 to 1.190, which were lower than those of background geological materials in Hong Kong (²⁰⁶Pb/²⁰⁷Pb: 1.201–1.279). The data also indicated that the Pb in the harbour sediments most likely originated from mixed sources, including the leaded gasoline used in the past and other anthropogenic sources.     

Variability of Airborne Dust Fallout and Associated Trace Metals around Industrial Sites in Esfahan,Iran

The seasonal and spatial variability of airborne dust deposits and associated trace metals such as Pb, Co, Ni, Cd, Mn in 15 sites surrounding a heavily industrialized region in south Esfahan (central Iran) are investigated. Total deposit rates (TDR) of dusts and trace metals are analyzed, contamination factor (CF) and pollution load index (PLI) are also calculated. Furthermore, correlation and cluster analysis are performed to identify the source of the pollution. The highest dust-TDR (15.97 g m⁻² per season), the highest concentration of trace metals, CF and PLI are recorded in summer because of the lack of precipitation, high temperature, and drought conditions in this season. Pb and Cd show the highest CF values. In the towns near the two major steel mills in the region (i.e., Esfahan Steel Company and Mobarekeh Steel Complex), the CF values for Pb and Cd are about 13 and 12, respectively (i.e., 13 and 12 times higher than the pre-industrial values, respectively). The spatial distribution maps of the dust deposit rate, dust-borne trace metals, and the obtained PLI of the trace metals in the study area reveal that the two major industries in the region are the main sources of dust and trace metal distribution.     

‘Oyster watch’: Monitoring trace metal and organochlorine concentrations in Sydney''s coastal waters

This paper examines concentrations of trace contaminants in oysters placed in inshore and offshore waters before and after the change to offshore disposal of sewage near Sydney, NSW, Australia. The ability to compare inshore and offshore concentrations before and after the event allows the formulation of unconfounded conclusions about the impact of sewage on the availablity of trace contaminants in the coastal environment and the effect of the change in the method of disposal of Sydney's sewage on the availability of those contaminants.

The data show clearly that the diversion of sewage from nearshore to offshore areas has resulted in a significant drop in the concentrations of organochlorines in oysters deployed near sewage outfalls in the nearshore region. In offshore areas, there were no differences detected among regions prior to the commissioning of deepwater outfalls. In the post commissioning period there were a number of instances when trace metal concentrations in the regions were different from each other, but these differences were not correlated with proximity to the sewage outfalls nor was a particular metal consistently elevated, so it was concluded that the causes of difference were not related to the presence of the sewage outfalls.

This study has demonstrated that oysters were useful indicators of trace metal and organochlorine contamination of marine waters; that relatively high levels of contamination of inshore waters near sewage outfalls prior to deepwater sewage disposal were reduced, to be not different from other parts of Sydney's coastline after the commencement of deepwater discharge, and that there was no concommitant increase in accumulation of contaminants in offshore waters. Further, preliminary indications are that Sydney's coastal waters are not very heavily contaminated by trace contaminants in comparison to areas of NSW with much lower levels of development. Concentrations of organochlorines are, however, high in comparison to data from similarly developed areas of the USA.     

Distribution of trace metals and Pb isotopes in bottom sediments of the Murucupi River,North Brazil

The Murucupi River belongs to the hydrographic network of the Pará River estuary, at the southern portion of the Amazon River mouth, which consists of a fluvial-marine transitional zone under strong impact of both tidal and fluvial currents. The geochemical results obtained for bottom sediments from the Murucupi River, the Arrozal Channel, and the Pará River indicate a natural variation of Pb, Cr, Cu, Zn, and Ni content among these water ways with no significant anthropogenic influence. According to the threshold effects level (TEL), the contents of trace metals do not offer risk to the local biota. By contrast, the differences in the Pb isotopic composition of sediments in the Murucupi River, the Arrozal Channel, and the Pará River are significant. These isotopic signatures indicate an anthropogenic contribution of Pb in the Murucupi River originating from the domestic effluents of urban centers; industrial waste represented by red mud is not included. These results demonstrate that the Pb isotopic signature is a prospective indicator for future contamination of bottom sediments by trace metals and is useful for identifying contaminants among the possible anthropogenic sources.     

Marine pollution from antifouling paint particles

Antifouling paint particles (APP) are generated during the maintenance of boats and are shed from abandoned structures and grounded ships. Although they afford a highly visible, colourful reflection of contamination in the vicinity of the source, little systematic study has been undertaken regarding the distribution, composition and effects of APP in the wider marine environment. This paper reviews the state of knowledge in respect of APP, with particular emphasis on those generated by recreational boatyards. The likely biogeochemical pathways of the biocidal and non-biocidal metals in current use (mainly Cu and Zn) are addressed in light of recent research and an understanding of the more general behaviour of contaminants in marine systems.Analyses of paint fragment composites from recreational facilities in the UK reveal chemical compositions that are similar to those representing the net signal of the original formulations; significantly, dry weight concentrations of Cu and Zn of up to about 35% and 15%, respectively, are observed and, relative to ambient dusts and sediment, elevated concentrations of other trace metals, like Ba, Cd, Cr, Ni, Pb and Sn, occur. These metals leach more rapidly from APP than a painted surface due to the greater surface area of pigments and additives exposed to the aqueous medium. In suspension, APP are subject to greater and more rapid environmental variation (e.g. salinity, pH, dissolved oxygen) than painted hulls, while settled APP represent an important source of persistent and degradable biocides to poorly circulating environments. Through diffusion and abrasion, high concentrations of contaminants are predicted in interstitial waters that may be accumulated directly by benthic invertebrates. Animals that feed non-selectively and that are exposed to or ingest paint-contaminated sediment are able to accelerate the leaching, deposition and burial of biocides and other substances, and represent an alternative vehicle for contaminant entry into the marine foodchain. Clearly, an extensive understanding of biocide behaviour on painted surfaces is not sufficient for predictive or management purposes regarding APP. Greater caution is required by boaters and boatyards during the removal and disposal of solid wastes, and more awareness or stricter enforcement of relevant codes of practice or legislation is recommended.     

Organochlorine pesticide and trace metal monitoring of Russian rivers flowing to the Arctic Ocean: 1990-1996

Information is presented on the concentrations of organochlorine pesticides (HCHs and DDT residues) and trace metals (Fe, Cu, Zn and Ni) in waters of 15 large Russian rivers flowing to the Arctic Ocean during 1990-1996. Estimates of the corresponding annual fluxes are made. Other contaminants (Hg, Pb, Cr, Mn, beta-HCH and dihydroheptachlor) were examined briefly. Concentration data are presented as averaged annual means for each of the seven years with the ranges, standard deviations and numbers of samples. Also given are data on locations, the methods of analysis and limited quality assurance data. Data on discharges to the Northern Seas for the more frequently monitored contaminants are given for rivers accounting for >70% of the total northerly flows. Scaled-up fluxes to account for unmonitored rivers as well are given for each sea; totals over the period were: Fe, 1452; Cu, 15; Zn, 59 (x 10(3) t yr(-1)); alpha-HCH, 25; gamma-HCH, 44 (t yr(-1)). Ni was monitored at too few rivers to estimate its total Russian flux. The fluxes for the HCHs considerably exceed previous estimates and indicate that the Arctic Ocean is not in balance as much as was previously believed.     

Unusual grain size effect on trace metals and organic matter in contaminated sediments

Grain size effect on trace metals (cadmium, copper, lead, zinc, and iron) and total organic content distribution in various fractions (<0.063, 0.063–0.105, 0.105–0.250, 0.250–0.500, and 0.500–1.000 mm) of contaminated sediment has been studied. Selective partitioning of the studied contaminants in sediment fractions was observed, with a minimum content in the fine sand fraction of grain size 0.125–0.250 mm. Anomalously high concentrations of trace metals and organic matter content in the medium and coarse sediment fractions (>0.250 mm) was explained by the formation of large agglomerates (clusters) during the generally recommended drying procedures. These large agglomerates, formed from smaller sediment fraction particles enriched by various contaminants kept on their large specific area by adsorption forces, have been observed in photographs of the medium and coarse sediment fractions only. The formed agglomerates consist of small particles cemented either by dissolved organic matter or by sea salts present in the marine sediment. The formation of such agglomerates should be taken into consideration when conducting metal contamination studies on sediments.     

Evaluation of a Florida coastal golf complex as a local and watershed source of bioavailable contaminants

Contaminant fate in coastal areas impacted by golf course runoff is not well understood. This report summarizes trace metal, pesticide and PCB residues for colonized periphyton, Ruppia maritima (widgeon grass), Callinectes sapidus Rathbun (blue crabs) and Crassostrea virginica Gemlin (Eastern oyster) collected from areas adjacent to a Florida golf course complex which receive runoff containing reclaimed municipal wastewater. Concentrations of 19 chlorinated pesticides and 18 PCB congeners were usually below detection in the biota. In contrast, 8 trace metals were commonly detected although concentrations were not usually significantly different for biota collected from reference and non-reference coastal areas. Residue concentrations in decreasing order were typically: zinc, arsenic, copper, chromium, lead, nickel, cadmium and mercury. Mean BCF values for the eight trace metals ranged between 160-57000 (periphyton), 79-11033 (R. maritima), 87-162625 (C. virginica) and 12-9800 (C. sapidus). Most trace metal residues in periphyton colonized adjacent to the golf complex, were either similar to or significantly less than those reported for periphyton colonized in nearby coastal areas impacted by urban stormwater runoff and treated municipal and industrial wastewater discharges. Consequently, the recreational complex does not appear to be a major source of bioavailable contaminants locally nor in the immediate watershed based on results for the selected biota.     

A review of Arctic trace metal data with implications for biological effects

This paper reviews much of the existing data on trace metal distributions in the Arctic. Numerous papers giving sediment data are reviewed, including some not yet published, fewer papers were found giving data on organisms and still fewer were found containing dissolved trace metal data. None of the data examined suggests that trace metals might be affecting the health of Arctic organisms. Rather, the trace metal concentrations found in Arctic waters, sediments and organisms, with few exceptions, are similar to those found in temperate areas thought to be largely free of pollutant levels of metals. Nevertheless, the existing data base for the Arctic is much smaller and more geographically restricted than that for temperate and tropical regions and the sensitivity of Arctic organisms to pollutant metals is not well known. Monitoring programs carefully designed to detect any influence of human activity on trace metal distributions in the Arctic should be initiated now.     

An assessment of residence times of land-sourced contaminants in the Great Barrier Reef lagoon and the implications for management and reef recovery

We argue that the residence times of key pollutants exported to the Great Barrier Reef (GBR) are greater in the GBR lagoon than those of the water itself, in contradiction to some previous assumptions. Adverse effects of the pollutant discharge will be greater and longer lasting than previously considered, in turn requiring stronger or more urgent action to remediate land practices. Residence times of fine sediments, nitrogen and phosphorus, pesticides and trace metals are suggested to be from years to decades in the GBR lagoon and highly likely to be greater than the residence time of water, estimated at around 15-365days. The recovery of corals and seagrass in the central region of the GBR following current land-use remediation in the catchment depends on the residence time of these contaminants. Ecohydrological modeling suggests that this recovery may take decades even with adequate levels of improved land management practices.     

Biodiversity reduction on contaminated sediments in the sea: contamination or sediment mobility?

Where contaminants in sediments correlate with biodiversity reductions, the contamination may not be the cause. Other physical factors may be responsible, and should be investigated so that any remedial action is directed properly. Two examples are given where unusual sediment mobility caused biodiversity reductions in sediments with elevated trace contaminants.     

湖泊疏浚堆场淤泥污染及潜在生态风险评价

疏浚淤泥内通常含有不同类型的有毒有害物质,在堆场直接堆放过程中可能会对周围环境产生有害影响.本文针对太湖及巢湖相应疏浚堆场内淤泥进行研究,探讨淤泥中重金属、多环芳烃以及多氯联苯等污染物含量及潜在生态风险;根据重金属的风险指数法和持久性有机污染物的风险商法,对各污染物的潜在生态风险进行定量分析.研究结果表明,太湖白旄堆场以及孔湾堆场淤泥内重金属及多环芳烃含量较小,潜在生态风险较低;巢湖南庄堆场淤泥内各类有害物质含量较大,种类较多,对于周围环境具有较高的潜在生态威胁.多氯联苯则在各个疏浚堆场淤泥中具有很高的积累量,潜在生态风险较高,应引起管理者的重视.     

Organic Contamination of Ground Water at Gas Works Park, Seattle, Washington

Gas Works Park, in Seattle, Washington, is located on the site of a coal and oil gasification plant that ceased operation in 1956. During operation, many types of wastes, including coal, tar, and oil, accumulated on-site. The park soil is currently (1986) contaminated with compounds such as polynuclear aromatic hydrocarbons, volatile organic compounds, trace metals, and cyanide. Analyses of water samples from a network of observation wells in the park indicate that these compounds are also present in the ground water.
Polynuclear aromatic hydrocarbons and volatile organic compounds were identified in ground water samples in concentrations as large as 200 mg/L. Concentrations of organic compounds were largest where ground water was in contact with a non-aqueous phase liquid in the soil. Where no non-aqueous phase liquid was present, concentrations were much smaller, even if the ground water was in contact with contaminated soils. This condition is attributed to weathering processes in which soluble, low-molecular-weight organic compounds are preferentially dissolved from the non-aqueous phase liquid into the ground water. Where no non-aqueous phase liquid is present, only stained soils containing relatively insoluble, high-molecular-weight compounds remain. Concentrations of organic contaminants in the soils may still remain large.     

Sensitivity of coastal waters to anthropogenic trace metal emissions

Trace metal concentrations in the waters of the Gulf of St. Lawrence and the Scotian Shelf and their sensitivity to changes in the composition of the major contributor of fresh water, the St. Lawrence River, are assessed. Comparison of the levels of trace metals in eastern Canadian coastal waters with those in other coastal waters of the world reveals that the former area generally has lower trace metal concentrations and is, therefore, probably less contaminated than elsewhere. The increased anthropogenic activity in the St. Lawrence drainage basin required to increase the levels of trace metals in receiving coastal waters by detectable amounts is discussed. We demonstrate that faster and more reliable warning of changes due to anthropogenic activity will be revealed through river monitoring than through monitoring of coastal waters. Changes in the marine environment can then be assessed through a thorough understanding of the geochemical behaviour of trace metals in nearshore waters.