Organochlorine Residues In Sediments Research Articles

Polychlorinated biphenyl and organochlorine pesticide residues in surface sediments from the Mediterranean Sea (Egypt)

The distribution pattern of organochlorine residues in sediments of the Mediterranean Sea (Egypt) has been investigated. The concentration of total organochlorine pesticides (OCPs) in surface sediments ranged from 0.11 to 50.73 with a mean of 14.52ng/g dry weight. The ratios used (DDD+DDE)/∑DDT, DDE/DDD and p,p′-DDT/∑DDT, indicate the degree of DDT׳s decomposition and identify the fresh input of DDTs. The predominant γ-HCH and the α-HCH/γ-HCH ratios indicate that there is a fresh input of lindane in some locations. The possible sources of OCs in the studied locations were estimated using multivariate statistical methods (principal component analysis (PCA), cluster analysis) for the data matrix obtained from the OC׳s analysis of the sediments. The potential environmental risk assessment associated with POPs measured in the sediments was conducted using the Risk Quotient (RQ).

Assessment of persistent organochlorine residues in sediments of Hadramout coastal area, Gulf of Aden, Yemen

Assessment of persistent organochlorine residues in sediments of Hadramout coastal area, Gulf of Aden, Yemen

Monitoring and Assessment of Persistent Organochlorine Residues in Sediments from the Daliaohe River Watershed, Northeast of China

Surface sediment samples from 12 sites of the three selected rivers in Daliaohe River watershed (Hunhe River, Taizihe River and Daliaohe River) were analyzed with the objective of establishing sources and hazard of the organochlorinae pesticides (OCPs) and polychlorinated biphenyl (PCBs) in surface sediments. The total concentrations of OCPs varied from 3.06 to 23.24 ng g(-1). SigmaHCH (alpha-HCH, beta-HCH, delta-HCH, gamma-HCH), SigmaDDT (p, p'-DDE, p, p'-DDD, o, p'-DDT, p, p'-DDT) and SigmaCyclodiene (Heptachlor, Aldrin, Heptachlor epoxide, Dieldrin, Endrin) ranged from 1.86 to 21.48, 0.5 to 2.81 and 0.56 to 1.53 ng g(-1), respectively. Results of OCPs also illustrate that the most dominant pollutants among the OCPs was SigmaHCH, and gamma-HCH was the most dominant isomer in HCH, which was evidence of recent input of lindane. It possibly came from the runoff of polluted soils and long-scale transportation. Total PCB concentrations ranged between 1.88 and 16.88 ng g(-1). The peak concentrations of PCBs were found in sediments from station T5 and D3, which are in the vicinity of industrial areas and ferry, respectively. These data show a moderate level of OCPs and PCBs contaminations compared to that in other countries.

Study and Measurement of Some Persistent Organochlorine Residues in Sediments from the Two Great Rivers (Tajan and Neka) of Mazandaran Province (Iran)

Study and Measurement of Some Persistent Organochlorine Residues in Sediments from the Two Great Rivers (Tajan and Neka) of Mazandaran Province (Iran)

Persistent organochlorine residues in sediments along the coast of mid-Black Sea region of Turkey

The aim of this study is to determine aspects of water and surface sediment quality in the coastal zone of the mid-Black Sea, and of rivers discharging into it, by analyzing their organochlorine pesticides (OC) levels. Surface sediment samples and water samples were collected from 14 sites from the rivers Yeşilırmak, Abdal, Mert, Kürtün, Engiz and Kızılırmak. In sediments, Aldrin ranged from 19.3 to 87.3 ng/g and p, p ′-DDT ranged from 18.6 to 31.0 ng/g.

Extractable organohalogens (EOX) in sediment and mussel tissues from the Kentucky Lake and Kentucky Dam Tailwater, USA

Extractable, organically bound chlorine (EOCl) concentrations in environmental samples have been used as one of the measures of pollution by chlorinated organics. Extractable organohalo‐gens (EOX = EOCl + EOBr + EOI) were measured in surface sediments and mussel tissues collected at selected locations in the Kentucky (KY) Lake and KY Dam Tailwater, USA. In sediments, EOX concentrations ranged from 0.22 to 0.90 μgg ‐1 dry wt. The sediment EOCl concentrations recorded in Kentucky Lake and KY Dam Tailwater were lower than those reported for sediments from industrial effluent contaminated sites. In freshwater mussel tissues, concentrations varied between 17.7 and 43.35 μgg ‐1 dry wt. Concentrations of EOCl measured in the tissues were comparable with those reported in fish and shellfish from PCBs and other chlorinated hydrocarbon contaminated sites. Extractable organochlorines (EOCl) were the highest in the total EOX family followed by organobromines and organoiodines. PCBs and chlorinated pesticides constituted only a minor part (<6% in sediment and <1 % in mussel tissues) of the EOCl, indicating the presence of additional, unknown organochlorine residues in sediments and mussel tissues from Kentucky Lake and KY Dam Tailwater. Elevated concentrations of EOCl and the proportions relative to the concentrations of EOBr and/or EOI in freshwater mussel tissues suggest that historical contamination as well as recent organic contaminant put in this region may be possible source of organic halogens in the environment.

Distribution and possible sources of organochlorine residues in sediments of a large urban estuary, Port Jackson, Sydney

Sydney Harbour is surrounded by a large capital city of about four million people and its highly urbanised (86%) catchment supports a substantial industrial base and an extensive transport infrastructure. Large commercial and naval ports occupy the waterway and the harbour is an important recreational area. Surficial sediment in Sydney Harbour contains high concentrations of PCBs, HCB, total chlordane, total DDT, aldrin, dieldrin, heptachlor and heptachlor‐epoxide, but low concentrations of lindane. PCBs, total chlordane, and to a lesser extent dieldrin, are most elevated in sediment in creeks on the southern shores of the harbour suggesting sources within older, highly urbanised/industrialised catchments of western‐central Sydney. There are high concentrations of total DDT and HCB in sediments of the upper harbour and Homebush Bay suggesting that chemical industries on the shores of the estuary in this area are sources of these contaminants. Although no sediment quality guidelines apply in Australia, empirically derived biological effects criteria suggest that sediment over extensive areas of Sydney Harbour may have an adverse impact on biota. Especially of concern are sediments containing high concentrations of chlordane and DDT.

Persistent organochlorine residues in sediments from Chinese river/estuary systems

Persistent organochlorine compounds were analyzed in surficial sediment samples from seven large Chinese river/estuary systems. The reported concentrations of organochlorine compounds in sediments collected from Zhujiang, Minjiang and Jiulongjiang were also presented for comparison. Concentrations of HCH were low in most sediments except the Zhujiang River, where the concentrations were one order of magnitude higher than for the other rivers. The levels of DDT were relatively low in sediments from north Chinese river/estuary systems while the values of DDT were high in South China. Higher concentrations of polychlorinated biphenyls (PCBs) were observed at Huangpujiang, Qiantangjiang and Changjiang, which drain highly industrialized and densely populated areas of China. Compared with the world's other river/estuary systems, the residue levels in these sediments were relatively low, though the production and usage of organochlorines in China is in large quantities. Great water discharge and/or sediment loads and biogeochemical processes such as biodegradation, volatilization, etc., may be responsible for low concentrations.

Persistent organochlorine residues in sediments of Hong Kong Victoria Harbour and Xiamen Western Bay

Samples of surface sediment were collected from Victoria Harbour, Hong Kong (Aug. 1992), and Xiamen Western Bay (Nov. 1993), and analysed for organochlorine (OC) pesticides (HCHs, DDTs) and polychlorinated biphenyls (PCBs). Concentration ranges of HCHs, DDTs and PCBs in the survey area of Victoria Harbour were from undetectable to 9.4 μg/kg, 1.38–97 μg/kg and 3.2–81 μg/kg, respectively; those for Xiamen Western Bay were 0.14–1.12 μg/kg, 4.45–311 μg/kg and 0.05–7.24 μg/kg, respectively. The determined residue levels and distribution patterns of these organochlorines are discussed, and the Harbour and Bay contamination levels are compared. Two sediment cores were collected (Oct. 1994) from Xiamen Western Bay for study on the vertical profiles and pollution history of the above contaminants. The vertical profile characteristics indicated that the inner part of Xiamen Western Bay was once polluted by PCBs moderately and that there are still new inputs of DDT.

Persistent organochlorine residues in sediments from the Chukchi Sea, Bering Sea and Gulf of Alaska

Three surface sediments and two sediment cores were collected from the Gulf of Alaska, Bering Sea and Chukchi Sea, and analysed for persistent organochlorines (OCs). The geographical distributions of OCs showed different patterns according to their physicochemical properties. The concentrations of HCHs and HCB revealed rather uniform distribution, suggesting their more transportable nature in long-range atmospheric transport. On the other hand, DDTs and PCBs were predicted to be less transportable via the atmosphere due to the decreasing trends of residue levels in sediments from south to north. The OC profiles in the sediment core from the Gulf of Alaska which seemed to be preserved without turbation revealed the elevated residue levels from bottom to surface layers. This implies that the aerial inputs of OCs in the cold ocean are still continuing significantly. The accumulation rates of OCs into sediments were rather smaller than the atmospheric inputs, indicating that the residue levels in water bodies are unlikely to decrease rapidly in the near future.

Organic compounds of environmental concern in the Gulf of Mexico: a review

An overview of the data available on the distribution of volatile organic compounds (VOC), high molecular weight hydrocarbons (HMWHC) and synthetic organochlorine compounds in sediments, water and organisms from the Gulf of Mexico is presented. VOC contain many environmentally important substances and are widespread contaminants in Gulf of Mexico coastal and nearshore waters. VOC, compounds with volatilities between those of ∼ n-C 5 and n-C 15, are highest near chemical plants, oil platforms and other industrial or urban centers. VOC detected include aromatics, chlorinated and brominated compounds, and alkanes. VOC concentrations and distributions are controlled initially by the dynamics of local sources but are ultimately determined by exchange with the atmosphere. The major sources of HMWHC in the Gulf of Mexico are biological production, natural seepage, petroleum production, shipping activities, coastal and riverine runoff, and atmospheric exchange and fallout with the dominant sources being very location-dependent. The more pristine areas are offshore from Florida and Southern Texas, whereas the coasts of upper Texas, Louisiana, and Alabama show the highest levels of contamination. The organochlorine compounds most commonly found in organisms are DDT metabolites, PCB and occasionally dieldrin. There is some evidence that estuarine biota contain higher levels of certain residues than pelagic organisms. Organochlorine residues in sediments are believed to originate from contamination by industry or agricultural activities. The highest levels detected to date are associated with Mississippi Delta sediments.

Limit of detection and limit of determination: Application of different statistical approaches to an illustrative example of residue analysis

For the analysis of organochlorine residues in sediments, sewage sludge and industrial waste water a new combination of well-known residue analytical steps has proved useful. Fortification experiments extensively performed should enable the estimation of limits of detection (LDC) and limits of determination (LDM) for 35 organochlorine compounds. The statistical evaluation of the analytical results showed, however, that with just 5 blank analyses and 5 analyses at a reasonable low fortification level, LDC and LDM estimates could be calculated which appeared to be exact enough for most purposes of daily residue analytical work.