Chlorinated hydrocarbons in marine biota and coastal sediments from the Gulf and Gulf of Oman

The spatial distribution of various organochlorinated compounds was investigated in the Gulf and Gulf of Oman based on marine biota (fish and various bivalves) and coastal sediment collected in Bahrain, Oman, Qatar and the United Arab Emirates (UAE) during 2000-2001. Several potential organic contaminants from agricultural (e.g., DDT and its breakdown products, lindane, endrin, dieldrin, endosulfan) and industrial (PCBs) sources were measured. Sediment burdens for all compounds, even for an apparent hot spot near a refinery in Bahrain, were amongst the lowest reported for surface sediments from other seas. Concentrations of DDTs were low in the muscle and liver of all fish (orange spotted grouper and the spangled emperor) analysed. Similarly, the levels of chlorinated hydrocarbons were low in the various bivalve species, notably rock oysters and pearl oysters. These results contribute to the sparse regional database for organochlorinated compounds in the marine environment. Moreover, they can be used as the most recent end point for elucidating temporal trends. Whereas the levels, albeit relatively low, SigmaDDTs in the rock oysters from the Gulf of Oman have remained uniform, there has been an irregular but generally decreasing trend in concentrations of summation SigmaPCBs during the last two decades.     

Assessment of organotin contamination in marine sediments and biota from the Gulf and adjacent region

Butyltin species were measured in sediments from coastal locations in the Gulf and Gulf of Oman. Both butyltin and phenyltin species were measured in biota samples from four countries in this region. With tributyltin (TBT) concentrations up to 60 ngSng(-1), some sediments could be classified as contaminated (i.e. TBT>1.3 ngSng(-1)), namely Dukhan (Qatar), the BAPCO industrial complex and Askar (Bahrain), and Hilf and the Raysut Port Area (Oman). Higher concentrations of total butyltins were found in oysters relative to fish, but ranging from 6.5 to 488 ngSng(-1) dry weight they are nonetheless relatively low. Diphenyltin and triphenyltin were found in some fish and bivalves from the Gulf, but not in biota from the Gulf of Oman. The environmental levels of organotin species are comparatively low by global standards and pose no immediate public health problems.     

Aliphatic and aromatic hydrocarbons in marine biota and coastal sediments from the Gulf and the Gulf of Oman

The composition and spatial distribution of aliphatic and polycyclic aromatic hydrocarbons (PAHs) were investigated in biota and coastal sediments from four countries surrounding the Gulf (Bahrain, Qatar, United Arab Emirates and Oman). The levels of total petroleum hydrocarbons (TPH), aliphatic unresolved mixture and PAHs in sediments and biota were relatively low compared to world-wide locations reported to be chronically contaminated by oil. Only in the case of the sediments collected near the BAPCO oil refinery in Bahrain, having concentrations of 779 μg g⁻¹ total petroleum hydrocarbon equivalents and 6.6 μg g⁻¹ ∑PAHs, can they be categorized as chronically contaminated. Some evidence of oil contamination was also apparent in sediments and bivalves around Akkah Head and Abu Dhabi in the UAE, and near Mirbat in Oman. Contaminant patterns in sediments and biota indicated that the PAHs were mainly from fossil sources, with the exception of the high PAH concentrations in sediments near the BAPCO refinery that contained substantial concentrations of carcinogenic PAH combustion products.     

Distribution of petroleum hydrocarbons and organochlorinated contaminants in marine biota and coastal sediments from the ROPME Sea Area during 2005

The composition and spatial distribution of various petroleum hydrocarbons (PHs), comprising both aliphatic and polycyclic aromatic hydrocarbons (PAHs), and selected chlorinated pesticides and PCBs were measured in biota and coastal sediments from seven countries in the Persian Gulf and the Gulf of Oman (Bahrain, Iran, Kuwait, Oman, Qatar, Saudi Arabia and the United Arab Emirates). Evidence of extensive marine contamination with respect to organochlorinated compounds and PHs was not observed. Only one site, namely the BAPCO oil refinery in Bahrain, was considered to be chronically contaminated. Comparison of the results from this survey for Σ DDTs and Σ PCBs in rock oysters from the Gulf of Oman with similar measurements made at the same locations over the past two decades indicates a temporal trend of overall decreasing Σ PCB concentrations in oysters, whereas Σ DDTs levels have little changed during that period.     

Levels of Cd,Cu, Pb and V in marine sediments in the vicinity of the Single Buoy Moorings (SBM3) at Mina Al Fahal in the Sultanate of Oman

Recently in the Sultanate of Oman, there has been a rapid surge of coastal developments. These developments cause metal contamination, which may affect the habitats and communities at and near the coastal region. As a result, a study was conducted to assess the level of metal contamination and its impact on the marine sediments in the vicinity of the Single Buoy Moorings 3 (SBM3) at Mina Al Fahal in the Sultanate of Oman. Marine subtidal sediment samples were collected from six different stations of the SBM3 for the period ranging from June 2009 to April 2010. These samples were then analyzed for their level and distribution of the heavy metals of cadmium (Cd), copper (Cu), lead (Pb) and vanadium (V). Overall, low concentrations of all four heavy metals were measured from the marine sediments, indicating that the marine at SBM3 is of good quality.     

Wadi flow in the Arabian Gulf states

Real data on wadi flood flows from Saudi Arabia, Yemen, Oman, Kuwait, UAE, Bahrain and Qatar were used to develop methodologies for the prediction of annual maximum flows and average monthly flows in the Arabian Gulf states. For the prediction of annual maximum floods, three methods have been investigated. In the first method, regional curves were developed and used together with the mean annual flood flow, estimated from the characteristics of the drainage basin, to estimate flood flows at a location in the basin. The second method fits data to various probability distribution functions, with a developed methodology introduced to account for floods generated by more than one system of climate, and the best fitted function was used for flood estimates. In the third method, only floods over a threshold, which depends on characteristics of the drainage basin, were considered and modelled. For the prediction of average monthly flows, stochastic simulation approaches of flood frequency analysis were used. Each of the prediction methods was verified by being applied in 40 different drainage basins. Based on the results obtained, recommendations were made on the best method to be applied (at present) by design engineers in the Arabian Gulf states. Copyright © 2006 John Wiley & Sons, Ltd.     

Concentration and subcellular distribution of trace elements in liver of small cetaceans incidentally caught along the Brazilian coast

Concentrations of trace elements (V, Cr, Mn, Fe, Co, Cu, Zn, Ga, As, Se, Rb, Sr, Mo, Ag, Cd, Sb, Cs, Ba, T-Hg, Org-Hg, Tl and Pb) were determined in liver samples of estuarine dolphin (Sotalia guianensis; n = 20), Franciscana dolphin (Pontoporia blainvillei; n = 23), Atlantic spotted dolphin (Stenella frontalis; n = 2), common dolphin (Delphinus capensis; n = 1) and striped dolphin (Stenella coeruleoalba; n = 1) incidentally caught along the coast of Sao Paulo State and Parana State, Brazil, from 1997 to 1999. The hepatic concentrations of trace elements in the Brazilian cetaceans were comparable to the data available in literature on marine mammals from Northern Hemisphere. Concentrations of V, Se, Mo, Cd, T-Hg and Org-Hg increased with increasing age in liver of both estuarine and Franciscana dolphins. Very high concentrations of Cu (range, 262-1970 microg/g dry wt.) and Zn (range, 242-369 microg/g dry wt.) were observed in liver of sucklings of estuarine dolphin. Hepatic concentrations of V, Se, T-Hg, Org-Hg and Pb were significantly higher in estuarine dolphin, whereas Franciscana dolphin showed higher concentrations of Mn, Co, As and Rb. Ratio of Org-Hg to T-Hg in liver was significantly higher in Franciscana dolphin than estuarine dolphin, suggesting that demethylation ability of methyl Hg might be lower in liver of Franciscana than estuarine dolphins. High hepatic concentrations of Ag were found in some specimens of Franciscana dolphin (maximum, 20 microg/g dry wt.), and 17% of Franciscana showed higher concentrations of Ag than Hg. These samples with high Ag concentration also exhibited elevated hepatic Se concentration, implying that Ag might be detoxified by Se in the liver. Higher correlation coefficient between (Hg+0.5 Ag) and Se than between Hg and Se and the large distribution of Ag in non-soluble fraction in nuclear and mitochondrial fraction of the liver also suggests that Ag might be detoxified by Se via formation of Ag2Se in the liver of Franciscana dolphin.     

Concentrations of trace elements in marine fish and its risk assessment in Malaysia

Concentrations of trace elements (V, Cr, Mn, Co, Cu, Zn, Ga, Se, Rb, Sr, Mo, Ag, Cd, Sn, Sb, Cs, Ba, Hg, Tl, Pb and Bi) were determined in muscle and liver of 12 species of marine fish collected from coastal areas in Malaysia. Levels of V, Cr, Mn, Co, Cu, Zn, Ga, Sr, Mo, Ag, Cd, Sn, Ba and Pb in liver were higher than those in muscle, whereas Rb and Cs concentrations showed the opposite trend. Positive correlations between concentrations in liver and muscle were observed for all the trace elements except Cu and Sn. Copper, Zn, Se, Ag, Cd, Cs and Hg concentrations in bigeye scads from the east coast of the Peninsular Malaysia were higher than those from the west, whereas V showed the opposite trend. The high concentration of V in the west coast might indicate oil contamination in the Strait of Malacca. To evaluate the health risk to Malaysian population through consumption of fish, intake rates of trace elements were estimated on the basis of the concentrations of trace elements in muscle of fish and daily fish consumption. Some specimens of the marine fish had Hg levels higher than the guideline value by US Environmental Protection Agency (EPA), indicating that consumption of these fish at the present rate may be hazardous to Malaysian people. To our knowledge, this is the first study on multielemental accumulation in marine fish from the Malaysian coast.     

Concentrations of trace elements in muscle of sturgeons in the Caspian Sea

Concentrations of 21 trace elements were determined in muscle of beluga (Huso huso), Persian sturgeon (Acipenser persicus), Russian sturgeon (Acipenser gueldenstaedtii), ship sturgeon (Acipenser nudiventris) and stellate sturgeon (Acipenser stellatus) collected from coastal regions of Azerbaijan, Iran, Kazakhstan and Turkmenistan, surrounding the Caspian Sea during 2000-2001. Concentrations of Mn, Co, Cu, Mo, Sn, Hg, Pb and Bi in the muscle were apparently different among the five species of sturgeons. Especially, beluga showed the highest concentrations of Hg, Pb and Mn in all the five species. In addition, more than half of the individuals of beluga exceeded the guideline level (0.3 microg/g wet wt.) of Hg for food in UK. However, V, Cr, Zn, Ga, Rb, Sr and Ba concentrations were similar among five sturgeons. Growth-dependent increase in Hg in beluga, Cu in Persian sturgeon, and Zn in Russian sturgeon were observed, whereas V, Mn, Co, Cu, Ga, Sr, Mo, Sn, Hg and Bi concentrations in Persian sturgeon, Pb in ship sturgeon, and Cr, Mn, and Rb in stellate sturgeon were negatively correlated with body length. All species of sturgeon in Azerbaijan showed the highest concentration of Sr and the lowest concentration of Rb, while the five sturgeons from Iran showed opposite trends. Concentration of V, which is present in oil, in sturgeons in the Caspian Sea was considerably lower than that of fish from Kuwait, but was comparable to that of Cambodia and the Gulf and Gulf of Oman. To our knowledge, this study provides the first extensive data on multielemental accumulation in sturgeons of the Caspian Sea.     

Mercury in feathers from Chilean birds: influence of location,feeding strategy,and taxonomic affiliation

This study reports baseline concentrations of mercury (Hg) in feathers from different species of birds sampled at various locations off the Chilean coast (Southeastern Pacific). Hg concentrations were evaluated in relation to geographic location, taxonomic affiliation, and feeding strategies. Between January and March of 1995, we collected mature contour feathers from 116 birds belonging to 22 species, mostly seabirds. Birds were collected from 10 different locations (26 degrees 09'S, 70 degrees 40'W to 54 degrees 56'S, 67 degrees 37'W). Feather Hg concentrations ranged from 0.11 to 13 microg g(-1) dry weight. We found differences in feather Hg concentrations across taxonomic groups, with highest concentrations in petrels, shearwaters, and albatrosses (Procellaridae), followed by boobies (Sulidae), gulls, terns, skuas (Laridae) and cormorants (Phalacrocoracidae). Ibises and oystercatchers (Threskiornithidae and Charadriidae) had intermediate values, whereas ducks and geese (Anatidae) contained the least amount of Hg. Oceanic species preying on mesopelagic fish (the Procellariformes albatrosses, petrels, and fulmars) had over twice as much Hg (overall average of 3.9 microg g(-1)) when compared to the rest of the species sampled (overall average of 1.5 microg g(-1)). We did not find higher Hg concentrations in birds inhabiting the more heavily industrialized and urbanized areas of the country (central and northern regions), but in birds inhabiting the remote Juan Fernandez Archipelago. This is not surprising, since all the Procellariformes (the group with highest Hg values in this study) were collected from these islands. Except for Hg in Kermadec petrels (mean of 12 microg g(-1)), the range of Hg values reported here (0.11-7.3 microg g(-1)) fell below those known to cause adverse health and reproductive effects in birds.     

Water pollution and habitat degradation in the Gulf of Thailand

The Gulf of Thailand has been a major marine resource for Thai people for a long time. However, recent industrialization and community development have exerted considerable stress on the marine environments and provoked habitat degradation. The following pollution problems in the Gulf have been prioritized and are discussed in details: (1) Untreated municipal and industrial waste water are considered to be the most serious problems of the country due to limited waste water treatment facilities in the area. (2) Eutrophication is an emerging problem in the gulf of Thailand. Fortunately, the major species of phytoplankton that have been reported as the cause of red tide phenomena were non-toxic species such as Noctiluca sp. and Trichodesmium sp. (3) Few problems have been documented from trace metals contamination in the Gulf of Thailand and public health threat from seafood contamination does not appear to be significant yet. (4) Petroleum hydrocarbon residue contamination is not a problem, although a few spills from small oil tankers have been recorded. A rapid decrease in mangrove forest, coral reefs, and fisheries resources due to mismanagement is also discussed.     

An assessment of metal contamination in coastal sediments of the Caspian Sea

An assessment of marine pollution due to metals was made in the Caspian Sea based on coastal sediment collected in Azerbaijan, Iran, Kazakhstan, Russia and Turkmenistan. Despite the high carbonate content, the distribution of most metals was largely controlled by terrigenous inputs. Several metals (As, Cr, Ni) exhibited concentrations that exceed sediment quality guidelines. Such metals have a high natural background but anthropogenic activities, notably mining, may further enhance concentrations. This would explain hot spots for Cu and Zn in Azerbaijan and Iran, and Cr at the mouth of the Ural River in Kazakhstan. Contamination by Hg was observed to the south of Baku Bay, Azerbaijan. Some anomalously high concentrations of Ba in the central Caspian are probably from offshore drilling operations, but the elevated U concentrations (up to 11.1 microg g(-1)) may be natural in origin. Several metals (Ag, Cd, Pb) have relatively low levels that pose no environmental concerns.     

A new certified reference material for the quality control of trace elements in marine monitoring: Cod muscle (CRM 422)

Analyses of fish tissues are routinely carried out by a number of laboratories to monitor the levels of contamination of the marine environment and food by toxic elements, e.g. by heavy metals. To improve and control the quality of such determinations, the Community Bureau of Reference (BCR) has organized a certification campaign which enabled us to produce a reference material (cod muscle CRM 422) certified for its contents of As, Cd, Cu, Fe, Hg, I, Mn, Pb, Se, and Zn. This material was collected in the southern part of the North Sea, carefully prepared (filleted and crushed under liquid nitrogen) and its homogeneity and long term stability were verified. This paper presents the certification work performed.     

Arsenic, cadmium, lead and mercury in canned sardines commercially available in eastern Kentucky, USA

Seventeen samples of canned sardines, originating from six countries and sold in eastern Kentucky, USA, were analyzed in composites of 3-4 fish each for total arsenic (As), cadmium (Cd) and lead (Pb) by graphite furnace atomic absorption spectrophotometry (AAS) and for mercury (Hg) by thermal decomposition amalgamation and AAS. Results in μg/g wet: As 0.49-1.87 (mean: 1.06), Cd < 0.01-0.07 (0.03), Pb < 0.06-0.27 (0.11), Hg ND < 0.09. Values fall generally within readings reported by others, but no internationally agreed upon guidelines have yet been set for As or Cd in canned or fresh fish. The incidence of cancers and cardiovascular diseases associated with As ingestion is extraordinarily high here. With the role of food-borne As in human illness presently under scrutiny and its maximum allowable limits in fish being reviewed, more studies of this nature are recommended, especially considering the potential importance of small pelagic fishes as future seafood of choice.     

Shore litter along sandy beaches of the Gulf of Oman

Beach debris abundance and weight were estimated from surveys on 11 beaches of the Gulf of Oman along the Omani coast. Debris were collected on two occasions from 100 m transects, sorted and categorized by origin and type. Overall contaminations ranged from 0.43 to 6.01 items m(-1) of beach front on different beaches with a mean value of 1.79+/-1.04 gm(-1) (95% C.I). In terms of weight, contamination levels ranged from 7.8 to 75.44 gm(-1) of beach front with a mean contamination of 27.02+/-14.48 gm(-1) (95% C.I). In terms of numbers of items, plastic debris ranked first on all beaches followed by either wood items or other organic materials such as cigarette butts. Industrial debris remained few on all beaches (<10%). Most debris had a local origin and, in terms of numbers, were associated with beach recreational activities whereas fishing debris represented the largest proportion of the debris in terms of weight. There were notable differences between beaches in the relative abundance of recreation-related and fishing-related debris.     

Distribution and ecological risk assessment of some heavy metals in coastal surface sediments along the Red Sea,Egypt

The ecological risk assessment for Al,Zn,Cu,Ni,V,Pb,Cd,and Hg in surface sediment collected from the Egyptian Red Sea coast was evaluated using the Geo-accumulation Index(I_(geo)).Sediment Enrichment Factor(SEF) and Potential Ecological Risk Index(PERI) methods.The predominant heavy metal,aluminum,showed high concentrations along both of Aqaba Gulf(4378.8 ± 2554.1 μg/g) and southern part of the Red Sea(2972.8 + 1527.5 μg/g).while it recorded the lowest concentration in Suez Gulf(829.7 ± 398.2 μg/g).The determined heavy metal concentrations had the order of Al Zn -Ni V Pb Cu Cd Hg.The statistical analyses showed some correlations among the heavy metals contents.Several international sediment quality guidelines were used to estimate the quality of the collected sediments.Interestingly,the recorded average heavy metals concentrations were lower than those of the permissible contents for sediment quality guidelines.The Geo-accumulation index calculations(I_(geo)) proved that the investigated region could be classified as an unpolluted area.Sediment Enrichment Factor(K_(SEF)) study showed high values in Suez Gulf region.The single pollution index analysis of heavy metals in the sediments(C~i_f) indicated that Al,Zn,V,and Pb were of natural origin,while Ni,Cd and Hg were seriously affected by human activities.Interestingly,amongst,all the determined heavy metals,Cd and Hg gave moderate ecological risk indicators.     

Atmospheric lead fallout over the last century recorded in Gulf of Lions sediments (Mediterranean Sea)

Six marine sediment cores from the Gulf of Lions continental slope (700-1700 m water depth) were analyzed for stable lead isotopes and (210)Pb geochronology in order to reconstruct lead atmospheric fallout pattern during the last century. The detrital lead contribution is 25 microg g(-1) and the mean sediment anthropogenic inventory is 110+/-7 microg cm(-2), a little bit higher than atmospheric deposition estimate. Anthropogenic lead accumulation in sediments peaked in early 1970s (1973+/-2) in agreement with lead emissions features. For the period 1986-1997, the sediment signal also reflect the decrease of atmospheric lead described by independent atmospheric fallout investigations. The anthropogenic Pb deposition in the late 1990s was similar to the 1950s deposition, attesting thus of the output of European environmental policies.     

Heavy metal contents in growth bands of Porites corals: record of anthropogenic and human developments from the Jordanian Gulf of Aqaba

In order to assess pollutants and impact of environmental changes in the coastal region of the Jordanian Gulf of Aqaba, concentrations of six metals were traced through variations in 5 years growth bands sections of recent Porties coral skeleton. X-radiography showed annual growth band patterns extending back to the year 1925. Baseline metal concentrations in Porites corals were established using 35 years-long metal record from late Holocene coral (deposited in pristine environment) and coral from reef that is least exposed to pollution in the marine reserve in the Gulf of Aqaba. The skeleton samples of the collected corals were acid digested and analyzed for their Cd, Cu, Fe, Mn, Pb and Zn content using Flame Atomic Absorption Spectrophotometer (FAAS). All metal profiles (except Fe and Zn) recorded the same metal signature from recent coral (1925–2005) in which low steady baseline levels were displayed in growth bands older than 1965, similar to those obtained from fossil and unpolluted corals. Most metals showed dramatic increase (ranging from 17% to 300%) in growth band sections younger than 1965 suggesting an extensive contamination of the coastal area since the mid sixties. This date represents the beginning of a period that witnessed increasing coastal activities, constructions and urbanization. This has produced a significant reduction in coral skeletal extension rates. Results from this study strongly suggest that Porites corals have a high tendency to accumulate heavy metals in their skeletons and therefore can serve as proxy tools to monitor and record environmental pollution (bioindicators) in the Gulf of Aqaba.     

Differential biomagnification of PCB, PBDE, Hg and Radiocesium in the food web of the European hake from the NW Mediterranean

Consumption of marine organisms represents one of the main exposure sources of contaminants for human populations. To obtain a global view of the contamination in commercial fish in the NW Mediterranean Sea, we analysed four types of priority contaminants (PCBs, PBDEs, Hg and (137)Cs) in the European hake, Merluccius merluccius, from the Gulf of Lions in relation with organism's trophic level (δ(15)N). All contaminants presented a significant increase in concentration in hake muscle with trophic level. However, obvious differences between contaminants were evidenced. Biomagnification factors (BMF and FWMF) along the hake food web were higher for Hg and CB-153 than for BDE-47 and (137)Cs, and increase in contaminant concentration with trophic level occurred at different rates depending on contaminants. Such differences of biomagnification patterns can be related to physico-chemical properties of the different contaminants.     

结合主成分分析法(PCA)和正定矩阵因子分解法(PMF)的鄱阳湖丰水期表层沉积物重金属源解析

为识别表层沉积物重金属的来源以及量化源贡献,选取鄱阳湖丰水期表层沉积物为研究对象,测定14种重金属(V、Cr、Co、Ni、Cu、Zn、Sr、Mo、Cd、Sb、W、Pb、Hg和As)的含量,分析其污染及空间分布特征,并利用主成分分析法(PCA)和正定矩阵因子分解法(PMF)对沉积物重金属进行源解析.结果表明:除V和Cr外,Cd、Mo、Hg、Cu、Pb、Zn、W、Sr、As、Ni、Co和Sb的平均含量分别为江西省土壤背景值的5.7、2.2、1.9、1.8、1.5、1.5、1.4、1.3、1.3、1.2、1.0和1.0倍; Cd、Hg、Cu、Mo、Pb、Sr和Zn超出江西省土壤背景值的比例相对较高,分别为100%、100%、100%、100%、97%、97%和93%,所有沉积物样品中Cd含量超过农用地土壤污染风险筛选值的比例为51%; V、Cr、Co、Ni、Cu、Zn、Sr、Mo、Sb、W、Pb、Hg和As含量呈未污染至弱污染水平,而Cd含量属于中等污染水平,接近于重污染水平.总体而言,Cd的污染相对较严重.重金属的分布具有显著的区域特征,其中Cr、Cu、Zn、Sr、Pb、Hg和As的空间分布十分相似,表现为在赣江、抚河、信江和饶河入湖口附近区域含量较高,而Co、Ni、Mo和Sb明显在湖区南部、东北部和修水入湖附近这3个区域聚集,Cd和W的空间变异性相对较大,V的含量分布相对较均匀.PCA和PMF解析结果都表明鄱阳湖丰水期表层沉积物重金属受4种来源的共同影响,其中,矿业和工业活动的影响最大,相对贡献率为38%,其次是尾矿和废渣,相对贡献率为28%,再是农业活动,相对贡献率为19%,最后是自然来源的相对贡献率为14%.