Residue levels of HCHs,DDTs and PCBs in shellfish from coastal areas of east Xiamen Island and Minjiang Estuary,China

Shellfish samples were collected from the coastal cultivating areas of east Xiamen Island and Minjing Estuary, China and analyzed for hexachlorocyclohexanes (HCHs), DDTs and polychlorinated biphenyls (PCBs) by GC. Concentration ranges of HCHs, DDTs and PCBs in the coastal area of east Xiamen Island were 0.18–345, 75.2–2143 and ND-23 ng g⁻¹ dry wt., respectively; those for Minjiang Estuary were ND-5.07, 21.5–2396 and ND-6.78 ng g⁻¹ dry wt., respectively. The results showed that the organochlorines were evidently accumulated in marine bivalve molluscs, particularly in oyster. The concentrations of organocholorine pollutants in shellfish samples varied with the sampling locations, the season of collection and organism species, but were generally higher than those in the sediments. The concentrations of DDTs in the shellfish were high as compared with HCHs and PCBs, so that DDTs can be considered as the typical organochlorines in the survey areas. The residue levels and compositions of HCHs, DDTs and PCBs are discussed.     

Geographical distribution and accumulation features of organochlorine residues in bivalves from coastal areas of South Korea

As a part of Mussel Watch Program in Korea, the contamination levels and accumulation features of polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) were assessed for 82 bivalve samples collected from 66 sites along the entire coast of Korea. The dry weight based ∑PCBs and ∑OCPs ranged from 4.4 ng g⁻¹ to 422.0 ng g⁻¹ (geometric MEAN=36.9 ng g⁻¹) and from 9.95 ng g⁻¹ to 131.37 (34.88) ng g⁻¹, respectively. PCB was predominant in Korean coast, followed by DDTs, HCHs, and Chlordanes. From the observed log normal distribution of PCB and each OCP, low- and high-levels were defined as geometric mean ±1 S.D., respectively. The levels at the sites near urban and/or industrial areas often exceeded the high-levels and the spatial distributions of ∑DDTs and ∑CHLs were correlated with that of ∑PCBs, indicating terrestrial input pathways. Even distribution of ∑HCHs suggested a possibility of atmospheric input pathway of HCHs. The observed isomer ratios of DDTs, HCHs, and CHLs indicated that aging has occurred.     

Organochlorines in Hong Kong Fish

Muscle samples from 15 species of fish (n=1) purchased from markets in Hong Kong and 10 liver samples of tilapia (Tilapia mossambica) collected from the Shing Mun River were analysed for organochlorines (polychlorinated biphenyls, ΣDDTs, hexachlorobenzene, hexachlorocyclohexanes, chlordanes, mirex and dieldrin). Polychlorinated biphenyls (PCBs) were detected in 15 market fish samples but the levels were very low (around 1 ng g⁻¹). PCB levels in tilapia livers collected from Tai Wai (29.3–65.1 ng g⁻¹) were higher than those from Fo Tan (3.5–23.2 ng g⁻¹) suggesting that there may be some local point soucres. ΣDDTs were detected in all samples, ranging from 3.3 to 75.6 ng g⁻¹ in the market fish and from 7.1 to 88.8 ng g⁻¹ in tilapia. The DDE/DDT ratios in the market fish (0.12–0.75) showed higher variability than those of tilapia (0.30–0.46), suggesting that some of the market fish may have been collected from areas where DDT was recently used. Results of this preliminary study show that organochlorine levels in Hong Kong market fish are low and do not cause any concern for human consumption. An on-going monitoring program, however, is recommended.     

Persistent organochlorine residues in green mussels from coastal waters of South India

Green mussels (Perna viridis) collected from nine locations along the South Indian coast were used as bioindicator to assess the organochlorine contamination (HCHs, DDTs, and PCBs) in the coastal environment of South India. Concentrations of ΣHCH and ΣDDT were found to be similar, ranging from 3 to 39 ng g⁻¹ on wet wt basis. On the other hand, PCB levels were apparently lower, varying from <1.0 to 7.1 ng g⁻¹ wet wt. The residue pattern of organochlorines in mussels are principally similar to those in Indian human samples, reported earlier. The coastal marine pollution by HCH in India ranks among the highly contaminated areas in the world.     

Pesticides in Sediments From Queensland Irrigation Channels and Drains

Pesticide concentration in sediment from irrigation areas can provide information required to assess exposure and fate of these chemicals in freshwater ecosystems and their likely impacts to the marine environment. In this study, 103 sediment samples collected from irrigation channels and drains in 11 agricultural areas of Queensland were analysed for a series of past and presently used pesticides including various organochlorines, synthetic pyrethroids, benzoyl ureas, triazines and organophosphates. The most often detected compounds were endosulphans (, β and/or endosulphan sulphate) which were detectable in 78 of the 103 samples and levels ranged from below the limit of quantification (0.1 ng g⁻¹ dw) up to 840 ng g⁻¹ dw. DDT and its metabolites were the second most often detected pesticide investigated (74 of the 103 samples) with concentrations up to 240 ng g⁻¹ dw of ∑DDTs. Mean ∑endosulphan and ∑DDT concentrations were 1–2 orders of magnitude higher in sediments from the irrigation areas which are dominated by cotton cultivation compared to those which are dominated by sugarcane cultivation. In contrast to these insecticides, the herbicides diuron, atrazine and ametryn were the compounds which were most often detected in sediments from irrigation drains in sugarcane areas with maximum concentrations in areas of 120, 70 and 130 ng g⁻¹ dw, respectively. In particular during flood events, when light is limiting, transport of these photosynthesis inhibiting herbicides from the sugarcane cultivation areas to the marine environment may result in additional stress of marine plants.     

Organochlorine micropollutants in the Jiulong River Estuary and Western Xiamen Sea, China

Organochlorine contaminants including 12 polychlorinated biphenyl (PCB) congeners and 18 insecticides were determined in water, pore water and sediments of the Jiulong River Estuary and Western Xiamen Sea, China. The results showed that the levels of the total PCBs ranged from non-detectable to 1500 ng l⁻¹ in water, from 209 to 3870 ng l⁻¹ in pore water, and from 2.78 to 14.8 ng g⁻¹ dry weight in sediments. Total organochlorine insecticide concentrations were from below the limit of detection to 2480 ng l⁻¹ in water, from 267 to 33400 ng l⁻¹ in pore water, and from 4.22 to 46.3 ng g⁻¹ dry weight in sediments. Concentrations of PCBs and insecticides in pore water were significantly higher than those in surface water, due to the high affinity of these hydrophobic compounds for sediment phase. The PCB congeners with the highest concentrations were CB153, CB180 and CB194, which together accounted for 68–87% of total PCBs in water, pore water and sediment. Among the hexachlorocyclohexane (HCH) compounds, beta-HCH was found to be a major isomer. Analysis of 1,1,1-trichloro-2,2-bis-chlorophenyl-ethane (DDT) and its metabolites showed that 1,1-dichloro-2[o-chlorophenyl]-2[p-chlorophenyl]-ethylene (DDE) was dominant in the group. In comparison to a 1998 study in the Western Xiamen Sea, levels of organochlorines were enhanced due probably to recent inputs and changes in sediments.     

Organochlorine and butyltin residues in deep-sea organisms collected from the western North Pacific,off-Tohoku,Japan

Organochlorine (OCs) and butyltin (BTs) residues were determined in deep-sea organisms collected from the western North Pacific, off-Tohoku, Japan. Among OCs, concentrations of polychlorinated biphenyls (PCBs) and DDTs (DDTs and its metabolites) were the highest in deep-sea organisms (maximum concentrations of 6700 and 13,000 ng/g lipid wt, respectively). Chlordane compounds (CHLs) were the next most abundant OCs, and hexachlorocyclohexanes (HCHs) and hexachlorobenzene (HCB) were the lowest. BTs were also detected at maximum concentrations of 570 ng/g wet wt. Concentrations of PCBs, CHLs and BTs in deep-sea organisms collected from the western North Pacific, off-Tohoku, were generally lower than those in deep-sea and shallow water organisms from Japanese coastal waters. On the other hand, considerable variations in the concentrations of OCs were found among deep-sea organisms analyzed. Several carnivorous fishes such as snubnosed eel, lanternshark and grenadiers accumulated some OCs such as PCBs, DDTs and CHLs at high concentrations of up to a few μg/g levels. In addition, the residue pattern of OCs and BTs in fishes showed a specific trend according to the sampling depth; higher concentrations of PCBs, DDTs and CHLs and lower concentrations of HCHs, HCB and BTs were found in fishes collected from greater depth (1000 m) compared to those from shallower waters. This trend is consistent with the results of our earlier study on mesopelagic myctophid fishes. Results of this study suggest vertical transport of hydrophobic OCs such as PCBs, DDTs and CHLs and its accumulation in benthic deep-sea organisms.     

A case study on fuel oil contamination in a mangrove swamp in Hong Kong

Mangroves commonly found along tropical and subtropical coastlines are susceptible to oil pollution. In December 2000, around 500 1 m tall Kandelia candel saplings at the age of 3–5 years old located at the foreshore region of Sheung Pak Nai swamp, Hong Kong SAR, were found to be damaged by oil pollution. More than 80% of the saplings were either dead or washed away and leaving less than 5% healthy saplings with dense green leaves. Elevated concentrations of light n-alkanes (ranging from n-C₁₄ to n-C₂₀), pristane and phytane were recorded in surface sediments collected in December 2000. The ratio between light and total n-alkanes was 0.4. The total petroleum hydrocarbons (60–80 μg g⁻¹ TPH) and unresolved complex mixtures (60–70 μg g⁻¹ UCM) were higher than the background values of other mangrove sediments in Hong Kong, which were 40 and 20 μg g⁻¹, respectively. In certain root zone sediments, TPH concentrations were above 1000 μg g⁻¹. These results suggest that surface sediments in Sheung Pak Nai were contaminated by petroleum oil, most likely by illegal discharge of fuel oil which occurred between 1998 and 2002. One year later, in December 2001, unhealthy saplings had recovered and re-grown. The concentrations of TPH and UCM in sediments declined to around 40 μg g⁻¹, pristane and phytane dropped by 80%, and the ratio of light to total n-alkanes was 0.15, suggesting that residual oil in sediments was weathered leading to a remarkable recovery of the unhealthy saplings.     

Horizontal and vertical distribution of PCBs and chlorinated pesticides in sediments from Masan Bay,Korea

Horizontal and vertical distributions of organochlorine compounds (OCs) were determined in sediments from Masan Bay. The concentrations of polychlorinated biphenyls (PCBs), dichlorodiphenyltrichloroethanes (DDTs), HCB, hexachlorocyclohexanes (HCHs) and chlordane related compounds (CHLs) in sediments were in the range of 1.24-41.4, 0.28-89.2, 0.02-0.59, nd-1.03, and nd-2.56 ng/g, respectively. The spatial distribution of OCs showed a negative gradient from the inner of the bay to outer part of the bay, indicating that the source of OCs was probably located inside the bay. Compositional pattern of PCB congeners showed a relatively high concentration of high-chlorinated congeners in the inner part of the bay and a relatively low concentration of low-chlorinated congeners in the outer part. In sediment core from Masan Bay maximum concentrations of PCBs and DDTs are observed in the subsurface samples and correspond to an age of early 1980s and late 1960s. The concentration profiles of PCBs and DDTs in sediments of Masan Bay appear to correspond to use of PCBs and DDTs in Korea.     

Specific accumulation of persistent organochlorines in bluefin tuna collected from Japanese coastal waters

Concentrations of persistent organochlorines (OCs) such as PCBs, DDTs, chlordanes (CHLs), HCHs and HCB were determined in the liver of bluefin tuna (Thunnus thynnus) collected from Japanese coastal waters in order to elucidate accumulation profiles and to evaluate the suitability of this species as a biomonitor for pollution in the open sea ecosystem. Concentrations of PCBs, DDTs and CHLs in bluefin tuna increased significantly with body length (30–190 cm). HCHs and HCB residues were comparable among all the sampling regions, and the levels of these chemicals did not show correlation with body length. These results suggest significance of dietary uptake of PCBs, DDTs and CHLs compared to the intake via the gill. On the other hand, equilibrium partitioning with ambient water is a major determinant of the levels of HCHs and HCB in tuna. Body-length normalized values (BLNV) of PCBs, DDTs and CHLs concentrations in bluefin tuna were calculated using the linear regression equation obtained from the plot of concentrations and body length. BLNV of these chemicals on a lipid wt basis, which was adjusted for 100 cm body length, were indicative of the present state water pollution by PCBs, DDTs and CHLs. These results suggest that bluefin tuna is a suitable bioindicator for monitoring OCs contamination in the open sea ecosystem.     

Tin and organotin in water, sediments, and benthic organisms of Poole Harbour

Tributyltin (TBT) concentrations in waters of Poole Harbour ranged between 2–139 ng l⁻¹ (as Sn) and increased to 234–646 ng l⁻¹ within marinas. Seasonal trends in contamination coincided with boat usage patterns and peaked during summer months. A combination of poor tidal flushing and removal of TBT to particulates restricts high levels of contamination to areas closest to marinas and moorings; TBT concentrations in benthic sediments decreased from 0.52 μg g⁻¹ near such sites to 0.02 μg g⁻¹ at the harbour mouth. Organotin accumulations in several benthic invertebrates including polychaetes (Nereis diversicolor), snails (Littorina littorea) and clams (Scrobicularia plana, Mya arenaria) reflect the distribution of contamination in the environment, though concentration factors (relative to water) vary considerably between species and were highest in sediment dwelling clams, notably Mya (1.3×10⁵). Compared to organotins, biological availability of inorganic tin is low.

Levels of TBT in parts of Poole Harbour exceed Environmental Quality Targets designed to protect marine life and may be responsible for poor recruitment, particularly in bivalves, at heavily contaminated sites.     

Identification and occurrence of brominated and nitrated phenols in estuarine sediments

Brominated and nitrated phenols were positively identified for the first time in estuarine sediments (Rhône estuary). 2,4-Dibromophenol, 2,4,6-tribromophenol and 2-nitrophenol were the major components present, exhibiting concentrations in the range of 7–5850 ng g⁻¹. The analysis of sediment extracts by CGC-MS in the negative ion chemical ionization (NICI) mode allowed also the identification of a series of bromochloro, dibromochloro and bromodichloronitrophenol and their alkylated derivatives. The observed seaward negative gradient of concentrations, suggests a land-based discharge as the principal source, probably originated in automobile emissions which are wash-out to the riverine streams by urban runoff. However, their precise origin remains to be identified.     

Time Trend of BHCs and DDTs in a Sedimentary Core in Macao Estuary, Southern China

BHCs and DDTs in a ²¹⁰Pb dated sedimentary core in Macao estuary were analysed with supercritical CO₂ extraction and GC-ECD. The concentrations of BHCs in the core sediment dated from 1962 ranged from trace level (相似文献   

Organochlorines and dioxin-like compounds in green-lipped mussels Perna viridis from Hong Kong mariculture zones

Concentrations of persistent organic pollutants including polychlorinated biphenyls (PCBs), organochlorine (OC) pesticides and dioxin-like compounds were measured in green-lipped mussels, Perna viridis, collected from seven mariculture zones in Hong Kong between September and October in 2002 in order to evaluate the status, spatial distribution and potential sources of pollution in these areas. Concentrations ranged from 300 to 4400 ng/g lipid weight for total OCs and 170–1000 ng/g lipid weight for total PCBs (based on 28 congeners). Relatively smaller DDT concentrations in mussels compared with previous studies suggest reduced discharges of DDTs from nearby regions into Hong Kong waters. Detection of a mixture of HCH isomers in the mussels indicated that Hong Kong waters were predominantly contaminated by technical HCHs rather than lindane. Mussel samples from all sampling locations elicited significant dioxin-like activity in the H4IIE-luc bioassay. The greatest magnitude of dioxin-like response (39 pg TEQ/g wet wt.) was detected in mussels from Ma Wan in the western waters of Hong Kong, which is strongly influenced by the Pearl River discharge. Human health risk assessment was undertaken to evaluate potential risks associated with the consumption of the green-lipped mussels. Risk quotient (RQ) for dioxin-like compounds was greater than unity suggesting that adverse health effects may be associated with high mussel consumption.     

Organochlorines and other environmental contaminants in muscle tissues of sportfish collected from San Francisco Bay

Edible fish species were collected from 13 locations throughout San Francisco Bay, during the spring of 1994, for determination of contaminant levels in muscle tissue. Species collected included white croaker, surfperch, leopard and brown smoothhound sharks, striped bass, white sturgeon and halibut. 66 composite tissue samples were analysed for the presence of polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (P0CBs), pesticides, trace elements and dioxin/furans. The US EPA approach to assessing chemical contaminant data for fish tissue consumption was used for identifying the primary chemicals of concern. Six chemicals or chemical groups were found to exceed screening values (SVs) established using the US EPA approach. PCBs (as total Aroclors) exceeded the screening level of 3 ng g⁻¹ in all 66 muscle tissue samples, with the greatest concentrations (638 ng g⁻¹) found near San Francisco's industrial areas. Mercury was elevated (> 0.14 μg g⁻¹) in 40 of 66 samples with the greatest concentrations (1.26 μg g⁻¹) occurring in shark muscle tissues. Concentrations of the organochlorine pesticides dieldrin, total chlordane and total dichlorodiphenyltri-chloroethane (DDT) exceeded screening levels in a number of samples. Dioxin/furans (as toxic equivalent concentrations (TEQ's)) were elevated (> 0.15 pg g⁻¹) in 16 of the 19 samples analysed. Fish with high lipid content (croaker and surfperch) in their muscle tissue generally exhibited higher organic contaminant levels while fish with low lipid levels (halibut and shark) exhibited lower organic contaminant levels. Tissue samples taken from North Bay stations most often exhibited high levels of chemical contamination. The California Office of Health Hazard Assessment is currently evaluating the results of this study and has issued an interim Health Advisory concerning the human consumption of fish tissue from San Francisco Bay.     

Hydrocarbon and coprostanol levels in seawater, sea-ice algae and sediments near Davis station in eastern Antarctica: A regional survey and preliminary results for a field fuel spill experiment

A survey of hydrocarbons and the sterol coprostanol, together with a hydrocarbon degradation experiment, was conducted in a coastal marine environment in East Antarctica. Aliphatic hydrocarbon levels in sea-ice algae were 1.9–12.5 mg m⁻² and in seawater particulate matter 0.07–0.17 μg l⁻¹. Sea-ice algae contained the diatom biomarker, the highly branched isoprenoid (ip) diene ipC_25:2, and Southern Ocean seawater particulate matter samples were distinguished from near shore samples by the presence of nC_21:6. Sea-ice algae and seawater particulate matter samples showed a predominance of even chain n-alkanes. Hydrocarbon levels in sediment samples from anoxic fjord basins were high (45–48 μg g⁻¹) compared to a sub-tidal marine sample (0.7 μg g⁻¹), and were predominantly of bacterial origin. Contaminants detected were linear alkyl benzenes in sewage effluent from Davis station, and polycyclic aromatic hydrocarbons (PAH) which were present in very low levels (parts per trillion) throughout the environment. High levels of 2,6-dimethylnaphthalene were found in anoxic sediment from Ellis Fjord and may arise from a novel bacterial source. Coprostanol concentrations in sediments ranged from 67 to 1280 ng g⁻¹. A dual origin is proposed from marine mammalian faeces and, at several sites, from conversion of algal-derived sterols by anaerobic bacteria. Future studies examining the impact of human sewage from scientific bases or other ventures should use care in interpreting results when such high baseline values, from marine mammalian input, may occur naturally around the Antarctic coast. The potential exists, however, for the technique to distinguish between human and mammalian inputs through measurement of the coprostanol to epicoprostanol ratio, particularly if undertaken with appropriate comparative sampling. Results for a hydrocarbon degradation experiment where a light fuel was applied to an Antarctic beach, showed loss of up to 99% of the fuel within 2 months, mainly by volatilization.     

PAH contamination of western Irish Sea sediments

Concentrations of the sum of 15 PAHs in 22 surficial sediment samples from the western Irish Sea ranged from below 100 ng g⁻¹ in sandy sediments to a maximum of 1422 ng g⁻¹ in the centre of the mud basin. The concentrations are typical of coastal shelf sediments, but greater than those observed for aquatic sediments remote from known anthropogenic sources. Organic C and the % sediment <15 μm were positively correlated with ΣPAH. ΣPAH was normalised to organic C and particle size (i.e. expressed as ΣPAH/C^org and ΣPAH/%<15 μm) and significant relationships were still observed with organic C and %<15 μm. The results are discussed in the context of using organic C to normalise concentrations of PAHs to assess contamination levels in sediments.     

Organochlorine pesticides and PCB residues in sediments of Alexandria Harbour,Egypt

Persistent organochlorine compound concentrations were determined for 23 surface sediment samples collected from Alexandria Harbor, Egypt. Total PCB concentrations ranged from 0.9 to 1210 ng/g with four to seven Cl-substituted biphenyls being the most prevalent PCBs congeners. Different PCB congener distribution patterns were observed, probably reflecting different inputs and attenuation at various locations. Total DDT concentrations varied from <0.25 ng/g to 885 ng/g. The ratios of DDTs (2,4^′- and 4,4^′-DDT)/total DDTs (DDTs plus metabolites) in sediment samples from certain sites were 0.86 or higher, indicating little attenuation or recent input of DDT. Total chlordane (the sum of heptachlor and its epoxide, oxy-, γ- and -chlordane and cis+trans-nonachlor) ranged from <0.25 to 44 ng/g with the highest concentration found in the Arsenal Basin. The geographic distributions of PCBs, total DDTs and total chlordane were similar. Chlorinated benzenes (CBs), hexachlorocyclohexanes (HCHs), aldrin, dieldrin, endrin, chloropyrifos, endosulfan, mirex and pentachloroanisole were below detection limits or detected at low concentrations in most of the samples. Sites that were contaminated with high concentrations of organochlorine compounds were associated with dense population and low energy environment. The contamination levels of PCBs, total DDTs and total chlordane were in high range compared to other locations worldwide.     

Coprostanol as sewage tracer in McMurdo Sound, Antarctica

Sediment cores from the vicinity of sewage outfalls off McMurdo Station as well as surface grab samples from different locations in the McMurdo Sound, Antarctica were analysed for coprostanol (5β-cholestan-3β-ol) and epicoprostanol (5β-cholestan-3-ol) to assess the degree of sewage addition to the Sound. Sediment samples close to the point source contain as much as 3 mg g⁻¹ dry sediment of coprostanol, whereas samples farther from the source, for example from New Harbour and Granite Harbour, contain only trace levels to 40 ng g⁻¹. Coprostanol in the sediments of latter locations most likely originates from seals rather than from sewage outfalls. It appears that sewage particles are very quickly incorporated into the sediment layers close to the discharge point in the eastern Sound. However, significant levels (930 ng g⁻¹) of fecal sterols were detected in Cape Armitage surface sediments, indicating that the sewage plume could also have reached the seawater intake station, situated in between the outfall and Cape Armitage sampling site. These results suggest the need for a sound environmental monitoring and assessment of the existing wastewater practices in the region.     

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.