Composition and distribution of organochlorine pesticide residues in surface sediments from the Wu-Shi River Estuary,Taiwan

The contamination of organochlorine pesticides (OCPs) in sediments from the Wu-Shi River estuary was investigated to evaluate the pollution potentials and distribution of OCPs in central Taiwan. A total of 19 sediment samples were collected at five sampling stations along the River estuary. The concentrations of OCPs were in the range of 0.99–14.5 ng/g-dry weight (dw) for ΣHCH (-, β-, γ-, δ-HCH), 0.46–13.4 ng/g-dw for Σcyclodiene and 0.53–11.4 ng/g-dw for ΣDDT (p,p^′-DDD, p,p^′-DDE, p,p^′-DDT). The mean concentrations of ΣHCH, Σcyclodiene and ΣDDT were 3.79, 4.87 and 2.51 ng/g-dw, respectively. The total concentrations of OCPs correspond to 1.73–71.9 μg/g-OC when normalized to TOC contents. Among the organochlorine pesticides, endosulfan sulfate, β-HCH, and p,p^′-DDD were the most dominant compounds in the sediments with the average concentrations of 1.97, 3.43 and 2.08 ng/g, respectively. Also, different contamination patterns among sampling seasons were observed. The measured concentrations of OCPs collected in spring were higher than those in autumn and winter. A linear relationship between sediment characteristics and OCP residues was also demonstrated. The results obtained in this study show that there still exist a variety of organochlorine pesticide residues in the sediments from the near shore of central Taiwan.     

Organochlorine pesticide residues in sediments and biota from the coastal area of Dar es Salaam city,Tanzania

Sediment and biota samples were collected from Msimbazi and Kizinga rivers and from the coastal marine environment of Dar es Salaam during both dry and wet seasons. The samples were analyzed for various organochlorine pesticide residues using GC-ECD and GC-MS. Dieldrin, p,p^′-DDT, p,p^′-DDE, p,p^′-DDD, o,p^′-DDT and γ-HCH were detected at significantly greater concentrations above the method detection limits. Recoveries of pesticide residues ranged 86.5–120% in sediments and 62–102% in biota. The average concentrations of total DDT in sediments for the two seasons were almost the same. Biota samples showed significant difference in levels of residues depending on mode of feeding and age of analyzed biota. p,p^′-DDT to total DDT ratios in all matrices indicated recent use of DDT. The levels of residues in sediments suggest possible adverse effects to humans consuming biota that are directly exposed to the sediments. This effect, which is associated with bio-concentration of residues in the tissues of edible aquatic biota, should not affect wildlife. In spite of concern on the adverse effect to humans posed by pesticide residues in sediments, edible biota from the examined water bodies were found to be safe for human consumption.     

PCBs and chlorinated pesticides in the atmosphere and aquatic organisms of Ross Island, Antarctica

PCBs, p,p′-DDT, p,p′-DDE and lindane (γ-hexachlorocyclohexane) were monitored in the lower atmosphere of Ross Island, in Antarctica for 2 yr. Geometrical means were 15.2 pg m⁻³ for PCBs, 2.0 pg m⁻³ for p,p′-DDT, 1.0 pg m⁻³ for p,p′-DDE and 25.8 pg m⁻³ for lindane. Atmospheric levels of lindane were positively correlated with temperature, and a significant difference was found between spring-summer and summer-winter concentrations. No season related differences were found for the other chlorinated hydrocarbons, possibly owing to their lower vapour pressure and the cold climate. Periods with increased atmospheric levels of PCBs and DDT compounds were recorded. Lindane, p,p′-DDE and PCBs were present in fish and zooplankton sampled close to Ross Island. Pollutant levels in the zooplankton (on an extractable fat basis) were highest during the Antarctic spring and autumn and were inversely correlated to their fat content.     

The role of burrowing beds and burrows of the SW Atlantic intertidal crab Chasmagnathus granulata in trapping organochlorine pesticides

The effect of crab beds and bioturbation activity of the SW Atlantic intertidal crab Chasmagnathus granulata on the organochlorine pesticide (OCP) concentrations in Bahía Blanca estuary, Argentina were studied. Total OCP concentration was significantly lower inside than outside the crab burrows. Nevertheless, the concentrations from outside the crab beds were lower than from outside crab burrows, which indicated that crab beds act as sinks of sediment-bound OCP due to the bioturbation activities of the crabs. The same distribution patterns were found in all sediments as well as in crabs, being cyclodienes>HCHs>DDTs, although large amounts of metabolites rather than the respective parental were found in the organism showing the capacity of C. granulata for metabolising parental compounds. These more water-soluble compounds are excreted by the faeces and finally removed by tidal flushing to the sea. Our results suggest that crabs when present play a role in the distribution of sediment-bound OCP and the crab beds are modifiers of the dynamic of organic pollutants in estuarine areas.     

Levels of organochlorine pesticide residues in some organs of the Ganges perch, Lates calcarifer, from the Ganges-Brahmaputra-Meghna Estuary, Bangladesh

Levels of organochlorine pesticide residues (p,p′ DDT, DDD, DDE, Aldrin, Dieldrin, Lindane, Heptachlor and BHC) were analysed in the dry and wet seasons in four organs (muscle, liver, gut and egg samples) of Ganges Perch, Lates calcarifer, collected during October–November–December, 1996 and May–June–July, 1997 from the Ganges–Brahmaputtra–Meghna estuary. The residues were analysed by using gas-chromatography (GC) in electron capture detector (ECD) mode and were verified by thin layer chromatography (TLC). Among the four organs analysed, the residues were found in the order egg > gut > muscle > liver. The pesticide residues were found in the order ∑DDT > Heptachlor >Dieldrin > Aldrin. Higher levels of residues were found during the dry season due to high lipid content in fishes. A positive correlation was observed between the pesticide residues (∑DDT and ∑OCs) and lipid contents of fish, and the correlation was found to be linear. The concentrations of pesticide residues in muscle, liver and gut were below the FAO/WHO (1993) recommended permissible limit except in eggs.     

Bioaccumulation factors of chlorinated hydrocarbons between mussels and seawater

The bioaccumulation of PCB and DDT compounds by mussels, Mytilus spp., from ambient seawater was determined by measuring concentrations of these chlorinated hydrocarbons in both mussels and seawater at four sites on the Mediterranean coast of France and two sites in California. Bioaccumulation factors were found to vary over an order of magnitude. Ratios of the concentrations of PCB in mussels, consisting predominantly of pentachloro-and hexachlorobiphenyls, to concentrations in ambient seawater ranged between 69 000 and 690 000; the corresponding ratios of concentrations of p,p′-DDE or p,p′-DDT ranged from 40 000 to 690 000. Although mussels appear to be appropriate and convenient indicator organisms of local chlorinated hydrocarbon contamination levels, the factors contributing to this variance must be determined before mussels are widely used in global monitoring programmes.     

Screening of Mercury and Persistent Organochlorine Pollutants in Long-Finned Pilot Whale (Globicephala melas) in the Faroe Islands

Results of mercury and organochlorine analyses in pooled muscle and blubber samples representing in all 417 long-finned pilot whales (Globicephala melas) sampled in 1997 in the Faroe Islands are presented. The 28 pooled muscle samples from (in all) 9 pods were analysed for total mercury and the same number of pooled blubber samples were analysed for PCB (IUPAC CBs no. 28, 52, 99, 101, 105, 118, 128, 138, 153, 170, 180, 183 and 187), p,p′-DDT and metabolites and o,p′-DDT and metabolites, cis () and trans (γ)-chlordane, cis- and trans-nonachlor, oxychlordane, mirex, hexachlorobenzene, β-HCH and toxaphene (Parlars no. 26 (T2), 32, 50 (T12), 62 (T20) and 69.     

Sulfate reduction using methane in sediments beneath a bathyal “cold seep” giant clam community off Hatsushima Island, Sagami Bay, Japan

Two sandy sediment cores (Cores D227-120 and D380) were collected from inside a deep-sea giant clam (Calyptogena soyoae) community off Hatsushima Island, western Sagami Bay, central Japan (35°59.9′N, 139°13.6′E; 1160 m deep) and a muddy sediment core (Core D227-202) was obtained from outside the community by the submersibleShinkai 2000. The chloride concentration of the pore waters is constant vertically and sulfate reduction using sedimentary organic matter occurs in Core D227-202 (21 cm long). The chloride concentrations are lower by 7% at the 7.5–9 cm depth in Core D227-120 (9 cm long) and by 3% at the 11–12 cm depth in Core D380 (16 cm long) than those of the overlying bottom waters in the cores from inside of the community. Sulfate concentration decreases remarkably and dissolved inorganic carbon, alkalinity, ammonium-N, and hydrogen sulfide concentrations increase significantly with increasing depth in Core D380.δ³⁴S values of sulfate ions increase from +20.5 to +35.3‰ andδ¹³C values of dissolved inorganic carbon decrease drastically from −7.0 to −45‰ with increasing depth from the top to the bottom of the core, although theδ¹³C values of the organic carbon of the sediments are−23.7 ± 0.9‰ in Core D380. These results indicate that sulfate reduction using methane is active within the sediments just beneath the living clams and that the hydrogen sulfide produced can be used by endosymbiotic sulfur oxidizing bacteria living in the gills ofC. soyoae in the community.     

Organochlorine Pesticide Residues in Soils and Sediments of the Herbert and Burdekin River Regions, North Queensland – Implications for Contamination of the Great Barrier Reef

Organochlorine pesticides were widely used in the Australian sugarcane industry from the early 1950s until the late 1980s. Erosion of sugarcane soils and subsequent transport of sediment bound contaminants in river run-off to the Great Barrier Reef lagoon is a growing concern as the cane industry continues to expand. Organochlorine pesticide residues can be used as tracers to examine the worst-case scenario of the spatial extent to which currently used, though less persistent, organic agricultural pesticides might extend. The coastal alluvial flood-plains of the Herbert and Burdekin Rivers in North Queensland have sugarcane growing as the major coastal land-use. Sediment cores and surface sediment samples were collected from near-shore coastal regions of the Herbert and Burdekin Rivers. In addition, soil samples from cane-fields in the two catchments were collected. Analyses of the marine surface sediment samples and three sediment cores revealed the absence of detectable concentrations of organochlorine pesticides (<5 pg/g). However, easily detectable concentrations were found in the sugarcane soil samples (0.01–45 ng/g).     

Biofouling confounds the uptake of trace organic contaminants by semi-permeable membrane devices (SPMDs)

The outer layers of layflat, low density polyethylene plastic tubing (the principal component of semi-permeable membrane devices, SPMDs) were biofouled at a clean site in Hong Kong coastal waters for periods of 1–4 weeks. Following pre-fouling, triolein was added to the SPMDs and, along with control (unfouled) devices, they were exposed to a range of organochlorine pesticides (-HCH, aldrin, p,p^′-DDT) and PAHs (anthracene, fluoranthene and benzo(a)pyrene) under laboratory conditions. Results showed that the uptake of contaminants by SPMDs was severely reduced by as much as 50% under fouling conditions in comparison to unfouled controls. The ultimate utility of SPMDs as passive monitors is thus reduced, although alternative measures, such as the use of permeability reference compounds may compensate, and allow for realistic evaluations of dissolved environmental concentrations in aquatic environments. However, due to the complexities involved in such procedures––especially as they need to be conducted on a case-by-case basis––the utility of SPMDs appears to be limited for estimates of bioavailability unless necessary calibrations are undertaken within each environment that the sampler is used.     

Uptake and depuration of PAHs and chlorinated pesticides by semi-permeable membrane devices (SPMDs) and green-lipped mussels (Perna viridis)

Semi-batch seawater experiments were conducted to follow the uptake and release of selected PAHs (anthracene, fluorathene, pyrene and B[a]P) and organochlorine pesticides (-HCH, aldrin, dieldrin, p,p′-DDT) in semi-permeable membrane devices (SPMDs) and green-lipped mussels (Perna viridis). Mathematical models were applied to describe the uptake and elimination curves of the contaminants for SPMDs, and kinetic parameters, such as uptake rate constants, and equilibrium triolein/water partitioning coefficients were calculated. SPMD data showed a good fit to estimate rate constant and partition coefficient equations, but only those contaminants which partitioned mainly in the dissolved phase (-HCH and dieldrin) were well explained for mussels. Poor conformity of the other contaminants indicated mussels uptake by routes other than diffusion, such as ingestion of algae. An apparent equilibrium state was only noted for -HCH in mussels. Aldrin was not detected in mussels in the first few days of exposure, indicating potential metabolism of this compound. B[a]P was not detected in the triolein of SPMDs, which suggests that the membrane may act as a reservoir. Loss of spiked B[a]P from the triolein was evident in a depuration experiment, which may indicate transfer to the membrane. Rate constants for mussels were higher than those for SPMDs, but the reverse was true for partition coefficients. Overall, mussels and SPMDs had similar uptake rates for all compounds in this study, excluding p,p′-DDT and dieldrin. Contaminant elimination took place more rapidly in mussels, implying that SPMDs are better candidates for detecting episodic discharge of organic contaminants.     

Imposex in Morula Granulata as Bioindicator of Tributyltin (TBT) Contamination in the Dampier Archipelago, Western Australia

This study was undertaken to examine the use of imposex in the tropical neogastropod whelk Morula granulata as bioindicator of tributyltin (TBT) contamination. Samples were collected from sites throughout the Dampier Archipelago; both impact sites close to intensive shipping activity and remote control sites. TBT in this area originates mainly from commercial vessels using the Port of Dampier that are >25 m in length and exempt from legislation controlling the use of TBT in antifouling paints. A field survey was undertaken in July 1997; 100 M. granulata were taken at each of 18 sites with varying vessel activity, and examined for imposex. The level of TBT contamination in the Archipelago was low; ranging from <0.3 to 25 ng Sn l⁻¹ in water,<0.3 to 80 ng Sn g−¹ in oyster tissue (Saccostrea cuccullata – prey of M. granulata), and <0.3 to 33 ng Sn g⁻¹ in whelks. Percentage of imposex in M. granulata ranged from 0% to 57%, and was correlated with distance to vessel activity (r=0.646, p<0.05). The only significant relationship of imposex with butyltin concentrations was with TBT in oysters (r=0.826, p<0.05), and dibutyltin (DBT) in whelks (r=0.783, p<0.05). It is postulated that this is because of interspecies variation in ability to metabolize TBT to DBT and MBT (monobutyltin), as well as induction of imposex in earlier life stages, so that imposex in adults could be a reflection of prior contamination. M. granulata is a suitable bioindicator of TBT contamination in the Dampier Archipelago, which could be used throughout the Indo-Pacific given its abundance in the region.     

The Impact of the Herbicide Diuron on Photosynthesis in Three Species of Tropical Seagrass

The impact and recovery from exposure to the herbicide diuron [DCMU; 3-(3′,4′-dichlorophenyl)-1,1-dimethylurea] was assessed for three tropical seagrasses, maintained in outdoor aquaria over a 10-day period. Photosynthetic stress was detected using chlorophyll a fluorescence, measured with a Diving-PAM (pulse amplitude modulated fluorometer). Exposure to 10 and 100 μg l⁻¹ diuron resulted in a decline in effective quantum yield (ΔF/F_m^′) within 2 h of herbicide exposure in Cymodocea serrulata, Halophila ovalis and Zostera capricorni. Effective quantum yield also declined over the first 24 h of exposure in H. ovalis at even lower diuron concentrations (0.1 and 1.0 μg l⁻¹). Effective quantum yield in H. ovalis and Z. capricorni was significantly depressed at all diuron concentrations (0.1–100 μg l⁻¹) after 5 days exposure, whereas effective quantum yield in C. serrulata was only significantly lower in plants exposed to highest diuron concentrations (10 and 100 μg l⁻¹). Effective quantum yield depression was present 5 days after plants exposed to 10 and 100 μg l⁻¹ diuron were returned to fresh seawater. These results indicate that exposure to herbicide concentrations present in nearshore Queensland sediments present a potential risk to seagrass functioning.     

ESR dating of the Eupchon fault, South Korea

We investigated temporal pattern of Quaternary fault activity of the Eupchon fault zone in the southeastern part of the Korean peninsula, using ESR dating of fault rocks. The counterfeit E′ signal significantly affected the equivalent dose on some samples. In particular, the counterfeit E′ signal tends to affect samples with E′ intensity close to saturation level. Storage at room temperature for 360 days and heating at 170 °C for 15 min. after γ-ray irradiation did not change significantly the intensities, the dose responses and ESR ages for OHC, Al, and Ti signals. ESR ages from the Eupchon fault zone range from 2000 to 500 ka. The fault rocks were reactivated at least five times 2000, 1300, 900–1100, 700–800, and 500–600 ka ago. These data indicate that long-term cyclic fault activity of this fault zone continued into the Quaternary. The results from this study suggest that the Eupchon fault zone can be classified as a potentially active fault and presents some potential seismic hazards to the nuclear power plant in its vicinity.     

Occurrence of estrogen-like substances in the marine environment of the Northern Mediterranean Sea

Evidence has been presented that a number of environmental agents perturbs the function of the sex hormone signalling pathways in marine animals.

In this work the estrogenic/antiestrogenic activity of coastal marine water samples from five sites of the Northern Mediterranean Sea was assayed using a recombinant Saccharomyces cerevisiae yeast strain (RMY326 ER-ERE) transfected with the human estrogen receptor . Extraction of potential EDCs from seawater was performed in columns packed with XAD-2 resins.

The estrogenic activity was calculated as percentage of the activity of 17β-estradiol (10 nM) and it ranged from 4.8% and 59.03%, significantly depending on sampling site (p = 0.0013) and season (p < 0.05). Antagonistic activity of extracts was also detected and the percentage of inhibition of estradiol-dependent β-galactosidase induction ranged to 52.8%. These results point the reliability of the yeast assay as a first level screening test to assess the quality of aquatic environments.     

Effects of some environmental parameters on the reproduction and development of a tropical marine harpacticoid copepod Nitocra affinis f. californica Lang

The effects of salinity, temperature, and light conditions on the reproduction and development of harpacticoid copepod, Nitocra affinis f. californica under controlled laboratory conditions were determined. Seven different salinity levels (5, 10, 15, 20, 25, 30, 35 ppt), four temperatures (20, 25, 30, 35 °C), three different light intensities (25, 56, 130 μmol m⁻² s⁻¹) and photoperiods (24 h:0 h, 1 h:23 h, 12 h:12 h LD cycle) were employed in this study. The highest (p < 0.05) overall reproduction and fastest development time were achieved by copepods reared under 30–35 ppt salinity. The optimum temperature required for the maximum reproduction was 30 °C while under 30 °C and 35 °C the copepod development time was shortest (p < 0.05) compared to other temperature levels. The overall reproduction was highest (p < 0.05) and development rate of N. affinis was shortest (p < 0.05) under lowest light intensity (25 μmol m⁻² s⁻¹). Continuous light (24 h:0 h LD) inhibited the egg production while, continuous darkness (1 h:23 h LD) and 12 h:12 h LD significantly favoured the overall reproductive activity of the female. Photoperiods 1 h:23 h and 12 h:12 h LD yielded highest total (p < 0.05) offspring female⁻¹ coupled with highest (p < 0.05) survival percentage. This study illustrated that although N. affinis can tolerate wide range of environmental conditions, prolonged exposure to subnormal environments affect its reproduction and development. This study showed that this species can be mass cultured for commercial purposes and has a potential to be used for toxicity studies due to its high reproductive performance fast development and a wide range of tolerance to environmental conditions.     

Physiological Responses of Five Seagrass Species to Trace Metals

Trace metal run-off associated with urban and industrial development poses potential threats to seagrasses in adjacent coastal ecosystems. Seagrass from the largest urban (Moreton Bay) and industrial (Port Curtis) coastal regions in Queensland, Australia were assessed for metal concentrations of iron (Fe), aluminium (Al), zinc (Zn), chromium (Cr) and copper (Cu). Trace metal concentrations in seagrass (Zostera capricorni) leaf and root-rhizome tissue had the following overall trend: [Fe] > [Al] > [Zn] > [Cr] > [Cu]. Rainfall events and anthropogenic disturbances appeared to influence metal concentrations in seagrasses with the exception of Al, which does not appear to bioaccumulate. In laboratory experiments, five seagrass species (Halophila ovalis, H. spinulosa, Halodule uninervis, Z. capricorni, Cymodocea serrulata) were incubated with iron (1 mg Fe l⁻¹) and copper (1 mg Cu l⁻¹) and responses assessed by changes in PSII photochemical efficiency (Fv/Fm), free amino acid content and leaf/root-rhizome metal accumulation. Iron addition experiments only affected Halophila spp, while copper additions affected other seagrass species as well. Trace metal contamination of seagrasses could have ramifications for associated trophic assemblages through metal transfer and seagrass loss. The use of photosystem II photochemical efficiency as well as amino acid concentrations and composition proved to be useful sublethal indicators of trace metal toxicity in seagrasses.     

Lysosomal membrane stability and metallothioneins in digestive gland of Mussels (Mytilus galloprovincialis Lam.) as biomarkers in a field study

The lysosomal membrane destabilization and the metallothionein content in the digestive gland cells of mussels (Mytilus galloprovincialis Lam.), collected along the east coast of the North Adriatic (Istrian and Kvarnerine coast, Croatia), were examined over a period of four years (1996–1999). The lysosomal membrane stability, as a biomarker of general stress, showed that the membrane labilization period in mussels from polluted, urban- and industrial-related areas was significantly decreased (p<0.05) when compared to mussels from control, clean sea water sites. In the harbour of Rijeka, the most contaminated site, the lysosomal membrane stability was reduced by more than 70% compared to the control. This method also proved to be a useful biomarker for detection of additional stress caused by short-term hypoxia that occurred once during this study inside the polluted and periodically quite eutrophic Pula Harbour. The concentration of metallothioneins in the mussel digestive gland, as a specific biomarker of exposure to heavy metals, did not reveal significant differences (p<0.05) between sites covered by this study.     

Pesticide and Trace Metal Concentrations in Queensland Estuarine Crabs

Trace metals, metalloids and pesticide content were quantified in intertidal burrowing crabs Australoplax tridentata and a portunid Scylla serrata sampled from estuaries on the east coast of Australia between Cairns and Brisbane. Residues of dieldrin occurred at all locations, heptachlor epoxide and DDT (principally metabolites DDD and DDE) at most, reflecting historical use. Chlordane, chlorpyrifos and endosulfan were only detected in crabs in the urban Brisbane area, and neither hexachlorobenzene (HCB) or polychlorinated biphenyls (PCBs) were quantifiable. Calculations of ambient exposures to organochlorines based on residues in crab tissues indicated that dieldrin exceeded national water quality guidelines for protection of aquatic ecosystems at all sampling locations, but exposure to DDT and its metabolites was below the threshold of concern. Concentrations of trace metals and metalloids generally reflected sediment data and likely sources.