PCB congener distribution in estuarine water,sediment and fish samples: implications for monitoring programs

Traditional analyses for PCBs in environmental matrices havefocused on commercial Aroclor mixtures with detection limits inthe 100 to 1000 part per trillion range. This approach hasrecently been supplanted by analyses for specific PCB compoundscalled congeners with detection limits less than 0.5 ppt. At thenational level, total PCB determinations based upon selected PCBcongeners typically characterize analyses of surface water,sediment and tissue. These federal efforts rely on a suite of 18to 20 congeners out of a total of 209 congeners to characterizetotal PCB. The present study compares total PCB estimates basedupon this subset of congeners with estimates based upon anexpanded list of 81 congeners from water, sediment and fishtissue collected from the Delaware Estuary.Analytical data from monitoring programs conducted in theDelaware Estuary by the Delaware River Basin Commission, NOAANational Ocean Service, U.S. Army Corps of Engineers and the U.S.Environmental Protection Agency from 1996 to 1998 were evaluated. Total PCB estimates derived from the different sets of congeners,including the adjustment factor of 2.0 used by NOAA, werecompared. This evaluation indicated that differences existbetween total PCB determinations based upon these approaches, andthat these differences vary depending on the matrix analyzed. The bias associated with using a smaller set of PCB congeners,and the implications for risk assessment are discussed.     

Metal concentrations in water, sediment, and fish from sewage-fed aquaculture ponds of Kolkata, India

The concentrations of lead, cadmium, chromium, copper, and zinc were investigated in the sewage-fed pond water, sediment, and the various organs of Labeo rohita, Catla catla, Cirrhinus mrigala, Oreochromis mossambicus, and Cyprinus carpio cultured in sewage-fed ponds, Kolkata, India. Among the metals, cadmium, lead, and zinc were detected in water and, except lead, were below the water quality guideline levels for the protection of freshwater aquatic life proposed by CEQG (Canadian Environmental Quality Guidelines) and AENV (Alberta Environment). Therefore, lead could pose danger to aquatic organisms. All the five metals were detected in the sediment and, except cadmium and lead, were below the sediment quality guideline levels for aquatic life proposed by EPA (Environmental Protection Agency). Therefore, these two metals could be toxic to aquatic organisms. Significant (P > 0.05) differences were observed among the five fish species for all these metals accumulation. Also, significant (P > 0.05) differences were noticed among these metals accumulation in fish organs. Cadmium showed the least bioaccumulation, while zinc showed the highest bioaccumulation in all the fish species. Though the metal concentration in the different fish tissues was variable, the highest concentration was found in kidney and the lowest in the muscle. Concentrations of these metals in the muscle tissue of all the fish species were well below the consumption safety tolerance in fish set by WHO/FAO, and thus, so far as these metals are concerned, these sewage-fed cultured fishes are safe and suitable for human consumption.     

An evaluation of selenium concentrations in water, sediment, invertebrates, and fish from the Solomon River Basin

The Solomon River Basin is located in north-central Kansas in an area underlain by marine geologic shales. Selenium is an indigenous constituent of these shales and is readily leached into the surrounding groundwater. Portions of the Basin are irrigated primarily through the pumping of selenium-contaminated groundwater from wells onto fields in agricultural production. Water, sediment, macroinvertebrates, and fish were collected from various sites in the Basin in 1998 and analyzed for selenium. Selenium concentrations were analyzed spatially and temporally and compared to reported selenium toxic effect thresholds for specific ecosystem components: water, sediments, food-chain organisms, and wholebody fish. A selenium aquatic hazard assessment for the Basin was determined based on protocol established by Lemly. Throughout the Basin, water, macroinvertebrate, and whole fish samples exceeded levels suspected of causing reproductive impairment in fish. Population structures of several fish species implied that successful reproduction was occurring; however, the influence of immigration of fish from low-selenium habitats could not be discounted. Site-specific fish reproduction studies are needed to determine the true impact of selenium on fishery resources in the Basin. The U.S. Government’s right to retain a non-exclusive, royalty free license in and to any copyright is acknowledged.     

Trace element concentrations in surface estuarine and marine sediments along the Mississippi Gulf Coast following Hurricane Katrina

Hurricanes are relatively frequent ecological disturbances that may cause potentially long-term impacts to the coastal environment. Hurricane Katrina hit the Mississippi Gulf Coast in August 2005, and caused a storm surge with the potential to change the trace element content of coastal surface sediments. In this study, surface estuarine and marine sediments were collected monthly following the storm from ten sites along the Mississippi Gulf Coast (Mobile Bay, Grand Bay Bayous Heron and Cumbest, Pascagoula, Ocean Springs, Biloxi Gulf, Back Biloxi Bay, Gulfport Gulf, Gulfport Courthouse Rd, and Gulfport Marina). Concentrations of V, Cr, Mn, Fe, Co, Ni, Zn, As, Cd, and Pb were measured by inductively coupled plasma–mass spectrometry to evaluate their temporal and spatial variations in the year following Hurricane Katrina. Sediments were characterized by pH, particle size distribution and total carbon and nitrogen content. Trace element contents of the sediments were determined in both <2 mm and <63 μm grain size fractions. Results revealed no significant temporal and spatial variability in trace element concentrations, in either size fraction. Potential ecological risk of the sediments was assessed by using NOAA SQuiRTs’ guideline values; most concentrations remained below probable adverse effects guidelines to marine organisms suggesting that trace elements redistributed by Hurricane Katrina would not cause an adverse impact on resident organisms. Instead, the concentrations of trace elements were site-dependent, with specific contaminants relating to the use of the area prior to Hurricane Katrina.     

Heavy metal concentrations in water, sediment, and tissues of two fish species (Triplohysa pappenheimi, Gobio hwanghensis) from the Lanzhou section of the Yellow River, China

In order to assess the condition of heavy metal pollution in the Yellow River, Lanzhou section, China, and to quantify heavy metal (copper, lead, zinc, and cadmium) contents in tissues (liver, kidney, gills, and muscles) of two fish species (Triplophysa pappenheimi and Gobio hwanghensis), levels of these four metals in the water body, sediment, and tissues of the two fish were measured using inductively coupled plasma-atomic emission spectrometry. The metal levels from this study were compared with the threshold values in the guidelines of water, sediment, and food given by the National Environmental Protection Agency of China, the National Oceanic and Atmospheric Administration of America, and the National Standards Management Department of China. We found the mean concentrations of Cu, Pb, Zn, and Cd in THE water body, sediment, and muscles of two fish species were far below the values in guidelines. We also found that the type of metals present and their concentrations varied in different tissues and species. The results suggested that (1) Cu, Pb, Zn, and Cd did not contaminate the aquatic ecosystem severely and did not threaten the safety of human consumption in the Yellow River, Lanzhou section, and (2) organs that are sensitive to accumulating heavy metals may be useful to develop bioindicators for monitoring metal contamination. Considering environmental variables, further study is necessary before deciding which fish species or tissue could be the ideal bioindicators for aquatic pollution.     

Alterations in the breeding habitats for two endangered raptor species along the Sava River basin, Croatia

Changes in habitat suitable for breeding of two sympatric raptor species (Haliaeetus albicilla and Aquila pomarina) were analysed along one of the most important breeding sites in Croatia for both species. The habitat suitability modelling was used to assess the influence of forestry practice during 2000-2006 using the known data on nesting places along research area. The four most important variables for lesser spotted eagle were elevation, distance from the nearest pasture, vertical distance to the nearest channel network and broadleaved forest placement (second axis from the principal component analysis of the enhanced vegetation index (EVI) index of MODIS images; November-March). The variables where white-tailed eagles showed greatest shift from overall habitat characteristics in the research area were broadleaved forest (second axis from the principal component analysis of the EVI index), height above the sea level, distance from the small settlements, vertical distance to channel network - all with negative loadings. The results clearly reveal the disproportion of suitable forests for raptors that were cut down in comparison to maturation of suitable forests.     

Heavy metal concentration in sediment, benthic, benthopelagic, and pelagic fish species from Musa Estuary (Persian Gulf)

The concentration of Cd, Co, Cu, Ni, and Pb was measured in sediment and three fish species collected from Musa Estuary, Persian Gulf. The concentration order of heavy metals in sediment were Ni > Co > Cu > Pb > Cd >. Concentrations of the heavy metals in the fish were apparently different among the three species. The concentrations of Cd and Ni in fish were Johnius belangerii > Euryglossa orientalis > Liza abu, while the Co and Cu levels were L. abu > E. orientalis > J. belangerii and E. orientalis > L. abu > J. belangerii, respectively. Result of regression analysis showed that there were no significant relationships between metal concentration in fish tissues and sediment, except for Ni concentration in the J. belangerii liver. The concentrations of studied metals in fish muscle were below the permissible limits proposed by FAO, WHO, and EC.     

Heavy metals in two fish species (Carangoidel malabaricus and Belone stronglurus) from Pulicat Lake, North of Chennai, Southeast Coast of India

We present the results from a detailed study based on five metals (Cr, Cd, Zn, Pb and Fe) measured in four organs (gills, liver, intestine and muscle) of two fish species (Carangoidel malabaricus and Belone stronglurus) from Pulicat Lake in southeast coast of India. The results show marked differences between the two species and organs as well as significant variations within the five analyzed metals. Although the metal concentrations measured in fish muscle are low, high levels of Pb and Fe were observed in the liver and gills of the two fish species. The concentrations of heavy metals in edible parts (muscle) of fish were within the permissible levels and are safe for the human consumption.     

Heavy metals contamination in water and three species of most consumed fish sampled from Caspian Sea, 2011

The present study is an attempt to evaluate the heavy metal contamination in the marine environment of the Caspian Sea of Iran. The concentrations of zinc, chromium, cadmium, and lead were measured in water and dorsal muscle of fish sampled from 10 selected stations along Gorgan coast using atomic absorption spectrophotometry during summer of 2011. The average concentrations of lead in water and fish samples (115.29?±?14.78 and 113.23?±?27.01 μg/L) were significantly higher than that of cadmium and chromium (P?<?0.05). The highest heavy metals content was observed in Cyprinus carpio samples. The heavy metals concentrations in the samples were within the acceptable recommended standards. But, elevating levels of heavy metals in water and fish made a serious concern about ecosystem and food chain contamination. It is recommended that protective authorities should carry out a continual assessment on the levels of pollutants in the sea.     

Determination of heavy metals in fresh water fish species of the River Ravi, Pakistan compared to farmed fish varieties

The untreated industrial and sewage wastes arising from industries and metropolitan activities make their passage to the River Ravi, Pakistan, where Balloki Headworks is one of the major sites of effluent concentration. This study was designed to evaluate the concentration of various toxic elements in fishes of that area compared to a nearby fish farm. The concentrations of heavy metals, such as As, Cd, Cu, Pb, Hg, and Zn, and electrolytes Ca, K, and Na were determined in different edible and non-edible fresh water fish varieties. Fish samples were collected from two selected sites and were analyzed for aforementioned elements. Higher levels of As (35.74–45.33 ppm), Cd (0.35–0.45 ppm), Pb (2.1–3.0 ppm), Hg (83.03–92.35 ppm) while normal levels of Zn (37.85–40.74 ppm) and Cu (1.39–2.93 ppm) were observed. Mercury, higher levels of which trigger cough, impairment of pulmonary function, and psychotic reactions, was significantly higher in all studied categories. At the sites under study, there has been observed alarming levels of toxic metals which are needed to be monitored regularly.     

Persistent organochlorine residues in fish and water birds from the Biobio river,Chile

Concentrations of polychlorinated biphenyls (PCBs), DDT and its metabolites, HCH isomers and hexachlorobenzene (HCB) were determined in fish and birds from different locations in the Biobio river basin (central Chile). Samples collected near the mouth of the river contained high concentrations of PCBs, reflecting the massive use of these xenobiotics in the urban and industrial areas of Concepcion and Talcauano. Samples collected in the central part of the basin contained very high concentrations of lindane that coincide with the widespread use of lindane-based pesticides (purified -HCH) in this area. DDT was distributed homogeneously throughout the basin, except at Laguna Icalma, the source of the river in the Andes. Most PCB residues in fish and birds consisted of congeners between penta- and hepta-chlorobiphenyls. In fish, the predominant congeners were the pentachlorobiphenyl 23445 (IUPAC number 118) and the hexachlorobiphenyl 2234455 (PCB-153); in birds 224455 (PCB-180) prevailed.     

Metal contamination in water, sediment and biota from a semi-enclosed coastal area

This study identifies and quantifies the spatial variations of metal contamination in water, sediment and biota: the common cockle (Cerastoderma edule) and the Mermaid’s glove sponge (Haliclona oculata), within a heavily anthropogenically impacted semi-enclosed estuarine–coastal area with a low ability to disperse and flush contaminants (Poole Harbour, UK). The results showed that metal contamination was detected in all environmental compartments. Water was polluted with As, and Hg sediment metals were mostly within “the possible effect range” in which adverse effects occasionally occurs. Cockles had considerable concentrations of Ni, Ag and Hg in areas close to pollution sources, and sponges accumulate Cu and Zn with very high magnitude. A systematic monitoring approach that includes biological monitoring techniques, which covers all embayments, is needed, and an integrated management of the semi-enclosed coastal zones should be based on the overall hydrological characteristics of these sensitive areas and their ability to self‐restore which is different than open coastal zones.     

Assessment of heavy metals in water samples and tissues of edible fish species from Awassa and Koka Rift Valley Lakes, Ethiopia

The Ethiopian Rift Valley Lakes host populations of edible fish species including Oreochromis niloticus, Labeobarbus intermedius and Clarias gariepinus, which are harvested also in other tropical countries. We investigated the occurrence of six heavy metals in tissues of these fish species as well as in the waters of Lake Koka and Lake Awassa. Both lakes are affected by industrial effluents in their catchments, making them ideal study sites. Mercury concentrations were very low in the water samples, but concentrations in the fish samples were relatively high, suggesting a particularly high bioaccumulation tendency as compared with the other investigated metals. Mercury was preferentially accumulated in the fish liver or muscle. It was the only metal with species-specific accumulation with highest levels found in the predatory species L. intermedius. Lower mercury concentrations in O. niloticus could be attributed to the lower trophic level, whereas mercury values in the predatory C. gariepinus were unexpectedly low. This probably relates to the high growth rate of this species resulting in biodilution of mercury. Accumulation of lead, selenium, chromium, arsenic and cadmium did not differ between species, indicating that these elements are not biomagnified in the food chain. Values of cadmium, selenium and arsenic were highest in fish livers, while lead and chromium levels were highest in the gills, which could be related to the uptake pathway. A significant impact of the industrial discharges on the occurrence of metals in the lakes could not be detected, and the respective concentrations in fish do not pose a public health hazard.     

Mercury accumulation in fish species from the Persian Gulf and in human hair from fishermen

Total and methylmercury concentrations were assessed in muscle and liver of 141 fish samples from the northern part of the Persian Gulf. All fish samples belonged to five different species: grunt, flathead, greasy grouper, tiger-tooth croaker, and silver pomfret. In addition, Hg and methylmercury were analyzed in scalp hair of 19 fishermen living in the same coastal stations of the Persian Gulf and consuming several fish meals a week. Total mercury concentrations in fish muscle and liver ranged from 0.01 to 1.35 μg g^???1 w.w. and from 0.02 to 1.30 μg g^???1 w.w., respectively. In fish muscle, 3% of the Hg concentrations were higher than 0.5 μg g^???1 w.w., which corresponds to the maximum acceptable WHO level, while 9% were in the range of polluted fish (between 0.3 and 0.5 μg g^???1 w.w.). The highest mercury concentrations in fish muscle were observed in flathead fish at Abadan (average of 0.68 μ g g^???1 w.w.). Methylmercury fractions in fish muscle and liver amount to 34–99% (median 64%) and 24–70% (median 43%), respectively. The mean total Hg concentration in the fishermen’s scalp hair amounted to 2.9 ± 2.2 μ g g^???1, with 68% in the form of methylmercury. Ninety-five percent of the Hg levels in the fishermen’s hair were below 10 μ g g^???1, which is the WHO warning limit. In addition, relationships between the mercury levels in hair, on the one hand, and exposure-related factors such as Hg levels in specific fish species, regional differences, and number of fish meals, on the other hand, are discussed. It appears that a significant correlation for example exists between Hg levels human hair and fish muscle or human hair and age and that mean mercury levels in fish muscle and human hair decreased from western (Abadan) to eastern (Abbas port) coastal sites.     

Mercury concentration in the muscle of seven fish species from Chagan Lake,Northeast China

Chagan Lake is located downstream of the Second Songhua River basin in Northeast China. It is one of the top ten inland freshwater lakes, and an important aquatic farm in China. The lake has been receiving large amounts (currently at 1.5 × 10⁸ m³/a) of water from the river since 1984. This would pose a threat to the aquatic system of the lake because the river was seriously polluted with mercury in 1970s–1980s. The current study is the first to report the total mercury concentrations in fish found in the lake. Mercury concentrations in seven fish species collected from the lake in January 2009 were determined. The related human health risk from fish consumption was also assessed. The average concentration of mercury in the fish was 18.8 μg/kg of wet weight, ranging from 4.5 to 37.6 μg/kg of wet weight. A large difference in the mercury concentrations among the fish species was found. The mercury concentration was found to be higher in carnivorous species and lower in omnivorous and herbivorous species. This demonstrates greater mercury bioaccumulation in fish species at higher trophic levels. Mercury concentrations in fish showed significant positive correlations with age, length, and weight. No significant relationship was found between mercury concentrations in fish and the habitat preferences. Mercury concentrations in fish from the lake were within the limits of the international and national standards of China established for mercury. According to the reference doses established by the United States Environmental Protection Agency, the maximum safe consuming quantity considering all the fish was 297.3 g/day/person, which was more than five times as much as the current quantity (50 g/day/person) consumed by the local residents. This investigation indicates that the historical pollution of the Second Songhua River has not caused mercury bioaccumulation in fish muscle tissue of Chagan Lake. The present consumption of fish from the lake in the local area does not pose a threat to human health.     

Polycyclic aromatic hydrocarbons in soils along the coastal and estuarine areas of the northern Bohai and Yellow Seas, China

Polycyclic aromatic hydrocarbons (PAHs) and their health risks in surface soils (n?=?31) collected from coastal and estuarine areas of the northern Bohai and Yellow Seas (CEANBYS), China, were investigated. Total concentrations of PAHs ranged from 6.6?×?10¹ to 9.2?×?10²?ng?g^?1 dry weight, with an average of 3.1?×?10²?ng?g^?1 dw. The locations where greater concentrations of PAHs were observed were all near factories emitting black smoke or on the edge of the urban areas. These observations are consistent with concentrations of PAHs in soils being influenced by human activities, especially industrialization and urbanization. Concentrations of PAHs were significantly correlated with concentrations of organic carbon in soils. The patterns of relative concentrations and types of PAHs observed as well as knowledge of the potential sources were consistent with the primary sources of PAHs in soils of the CEANBYS being derived from the pyrolytic processes such as combustion of fossil fuel. The incremental lifetime cancer risks of exposing to PAHs for child, youth, and adult were 1.6?×?10^?6, 1.2?×?10^?6, and 1.9?×?10^?6.     

Mercury accumulation in sediment and fish from rivers affected by alluvial gold mining in the Brazilian Madeira River basin,Amazon

The degree and distribution of mercury (Hg) accumulation in sediment and fish from a tributary affected by alluvial small-scale gold mining in the Madeira River/Amazon is studied, in relation to a reference site. The results obtained so far agree well with previous studies and confirm that a tremendous contamination of main food web compartments occurs in these highly exposed, but vulnerable tropical waters. An essential part of the released metallic Hg may still exist as macroscopic liquid Hg drops in the sediment. Both global (0.4 mg/kg of Hg) and local (0.1 mg/kg of Hg) background sediment values as well as safety levels for fish (0.5 mg/kg of Hg) are considerably exceeded by a factor of up to 25, 100, and 4, respectively, and give rise to serious concern, not least with regard to the formation of the very toxic monomethyl-Hg. It is further discussed that atmospheric transport and deposition of Hg in water reservoirs built for hydroelectric power generation may act as critical pathways for longterm Hg accumulation, even in unexposed riverine systems.     

Water and sediment quality of dry season pools in a dryland river system: the upper Leichhardt River, Queensland, Australia

This article presents the geochemical characteristics and physicochemical properties of water and sediment from twelve semi-permanent, dryland pools in the upper Leichhardt River catchment, north-west Queensland, Australia. The pools were examined to better understand the quality of sediments and temporary waters in a dryland system with a well-established metal contamination problem. Water and sediment sampling was conducted at the beginning of the hydroperiod in May and September 2007. Water samples were analyzed for major solute compositions (Ca, Na, K, Mg, Cl, SO(4), HCO(3)) and water-soluble (operationally defined as the <0.45 μm fraction) metals (Cd, Cu, Pb, Zn). Sediment samples were analyzed for total extractable and bioaccessible metals (As, Cd, Cu, Pb, Zn), elemental composition and grain morphology. At the time of sampling a number of pools contained water and sediment with elevated concentrations, compared to Australian regulatory guidelines, of Cu (maximum: water 28 μg L(-1); sediment 770 mg kg(-1)), Pb (maximum: water 3.4 μg L(-1); sediment 630 mg kg(-1)) and Zn (maximum: water 150 μg L(-1); sediment 780 mg kg(-1)). Concentrations of Cd and As in pools were relatively low and generally within Australian regulatory guideline values. Localized factors, such as the interaction of waters with anthropogenic contaminants from modern and historic mine wastes (i.e. residual smelter and slag materials), exert influence on the quality of pool waters. Although the pools of the upper Leichhardt River catchment are contaminated, they do not appear to be the primary repository of water and sediment associated metals when compared to materials in the remainder channel and floodplain. Nevertheless, a precautionary approach should be adopted to mitigating human exposure to contaminated environments, which might include the installation of appropriate warning signs by local health and environmental authorities.