[Show abstract][Hide abstract] ABSTRACT: Millions of tourists visit Kenting National Park (KNP) in southern Taiwan every year, causing great amount of sewage discharges in this area. This study aimed to assess the impact of sewage on KNP surface waters using zebrafish embryo-larval bioassays combined with chemical analyses of pharmaceuticals and personal care products (PPCPs). Surface water samples were collected monthly from May to October in 2010. During the monthly bioassays, zebrafish embryos were exposed to the water samples for 144 h. Hatchability, embryonic heart rate, larval survival rate, and deformities were recorded. Larval swimming behavior was also digitally quantified at the end of exposure. Significant decreases in hatchability and larval survival rate were observed at all sites. Both hatchability and larval survival rate were negatively correlated with nitrite and ammonia concentrations in the water. The field water had little effect on embryonic heart rate and morphology. However, lower swimming speeds and activity levels were observed in the larvae, suggesting neurobehavioral toxicity of the surface waters. The general detection frequency of the 28 target PPCPs was 75 %. High levels of some PPCPs, particularly caffeine, N,N-diethyl-3-methylbenzamide (DEET), and nonylphenol, were measured in the water samples. Our results show that surface waters in KNP have been strongly impacted by human activities, resulting in lethal and behavioral toxicities in developing fish.
[Show abstract][Hide abstract] ABSTRACT: Intracellular lipid droplets (LDs) have been proposed to play a key role in the mutualistic endosymbiosis between reef-building corals and the dinoflagellate endosymbiont Symbiodinium spp. This study investigates and identifies LD proteins in Symbiodinium from Euphyllia glabrescens. Discontinuous Percoll gradient centrifugation was used to separate Symbiodinium cells from E. glabrescens tentacles. Furthermore, staining with a fluorescent probe, Nile red, indicated that lipids accumulated in that freshly isolated Symbiodinium cells and lipid analyses further showed polyunsaturated fatty acids (PUFA) was abundant. The stable LDs were purified from endosymbiotic Symbiodinium cells. The structural integrity of the Symbiodinium LDs was maintained via electronegative repulsion and steric hindrance possibly provided by their surface proteins. Protein extracts from the purified LDs revealed a major protein band with a molecular weight of 20 kDa, which was termed Symbiodinium lipid droplet protein (SLDP). Interestingly, immunological cross-recognition analysis revealed that SLDP was detected strongly by the anti-sesame and anti-cycad caleosin antibodies. It was suggested that the stable Symbiodinium LDs were sheltered by this unique structural protein and was suggested that SLDP might be homologous to caleosin to a certain extent.
[Show abstract][Hide abstract] ABSTRACT: Surface sediments and corals (Acropora sp. and Montipora sp.) from the coastline of Kenting were analyzed in 2009 and 2010 for content levels of polycyclic aromatic hydrocarbons (PAHs) using gas chromatography-mass spectrometry. The total PAH concentrations (t-PAH) in corasls (143-1715 ng g(-1) dw) were significantly higher than in the ambient sediments (2-59 ng g(-1) dw) indicating the bioaccumulation of PAHs in corals. The spatial and seasonal variation in PAH levels suggested that land-loaded contaminants may be the main source of PAHs in the Kenting coral reefs. Based on molecular indices, PAHs were substantially of petroleum origin. The major PAH components were phenanthrene, pyrene and fluorine, but PAH congeners in corals and sediments still have characteristic composition patterns which would be altered by the bio/accumulation mechanisms. Further study is essential to assess and understand the impacts of these chemicals on coral reefs.
[Show abstract][Hide abstract] ABSTRACT: Air-water exchange fluxes of polycyclic aromatic hydrocarbons (PAHs) were simultaneously measured in air and water samples from two sites on the Kenting coast, located at the southern tip of Taiwan, from January to December 2010. There was no significant difference in the total PAH (t-PAH) concentrations in both gas and dissolved phases between these two sites due to the less local input which also coincided to the low levels of t-PAH concentration; the gas and dissolved phases averaged 1.29±0.59ngm(-3) and 2.17±1.19ngL(-1) respectively. The direction and magnitude of the daily flux of PAHs were significantly influenced by wind speed and dissolved PAH concentrations. Individual PAH flux ranged from 627ngm(-2)d(-1) volatilization of phenanthrene during the rainy season with storm-water discharges raising dissolved phase concentration, to 67ngm(-2)d(-1) absorption of fluoranthene during high wind speed periods. Due to PAH annual fluxes through air-water exchange, Kenting seawater is a source of low molecular weight PAHs and a reservoir of high molecular weight PAHs. Estimated annual volatilization fluxes ranged from 7.3μgm(-2)yr(-1) for pyrene to 50μgm(-2)yr(-1) for phenanthrene and the absorption fluxes ranged from -2.6μgm(-2)yr(-1) for chrysene to -3.5μgm(-2)yr(-1) for fluoranthene.
[Show abstract][Hide abstract] ABSTRACT: Surface sediment samples were collected in He-Ping Harbor and the nearby He-Ping Estuary from 2005 to 2006 to examine spatial and temporal variability in polycyclic aromatic hydrocarbon (PAH) concentrations. The sum of the 16 USEPA priority pollutant PAHs varied from 8 to 312 ng/g dry weight, which was relatively low compared to values obtained from other studies in the world. Regarding temporal changes in the PAH profile, total PAH concentrations in the wet season were lower than during the dry season in He-Ping Harbor. However, the concentration of PAHs exhibited no significant difference in the four seasons in the He-Ping Estuary. PAH concentrations in He-Ping Harbor were higher than those in the He-Ping Estuary. In comparison with sediment quality guidelines, PAH concentrations of sediments in this study were lower than those outlined in the criteria, which suggests no evident adverse biological effects due to PAHs around the He-Ping coast. Ratios of specific PAH compounds calculated to assess the possible sources of PAHs reflect that PAHs in He-Ping Harbor may mainly be from pyrogenic coal combustion.
[Show abstract][Hide abstract] ABSTRACT: Polychlorinated biphenyls (PCBs) are a group of widespread contaminants, and accumulation of PCBs has been observed in corals in the field. However, the toxic effects of PCBs on corals have not been investigated. In this study, we tested short and long term toxicity of Aroclor 1254, a commercial PCB mixture, on the scleractinian coral Stylophora pistillata. Coral nubbins were incubated in either control seawater or seawater dosed with PCBs (approximately 300ng/L) for 96h. The effect of PCB exposure on coral gene expression at 4h post exposure was tested with the suppression subtractive hybridization (SSH) and quantitative PCR methods. Photosystem II activity of the zooxanthellae was measured at 96h. After the exposure, nubbins were moved into clean seawater and their survival and growth were observed for another 50 days. All nubbins survived during the exposure and the following 50-d recovery period. Photosystem II activity and coral growth were not affected by PCB exposure in this study. Fifty-four clones were sequenced for gene expression analysis, and 15% of these sequences were identified, including genes involved in general stress response, peptide metabolism, cellular receptor, cytoskeleton organization, membrane trafficking, and oxidative stress response. However, the quantitative PCR did not show significant difference in the five selected genes. In conclusion, acute exposure of S. pistillata to Aroclor 1254 at 300ng/L did not affect coral survival, photosynthesis or growth but may alter the expression of certain genes involved in various important cellular functions. The nubbin technique proved to be an efficient approach to simultaneously characterize the impact of PCBs on the corals at multiple biological levels.
[Show abstract][Hide abstract] ABSTRACT: The main objective of this study was to investigate the concentrations of polycyclic aromatic hydrocarbons (PAHs) in inter-tidal sediments of the Kenting coast, Taiwan, to assess the levels and origin of PAHs, and to provide useful information on the potential ecological risk of PAHs to benthic organisms. The total concentrations of 38 PAHs ranged from 0.2 to 493 ng/g dry weight. The high variation in total PAH concentrations was caused by the sand content of the sediment in the area. Compared with other coasts and bays in the world, the concentrations of PAHs in the inter-tidal surface sediment of the Kenting coast is low to moderate. Based on the sediment quality guidelines, the total PAH concentrations were below the effects range low value, indicating that the PAH levels in the Kenting area were within minimal effects ranges for benthic organisms. Principal component analysis and isomer ratios were analyzed to identify the contamination source in the inter-tidal surface sediment of the Kenting coast. The results of compounds' pattern and origin analysis suggest that the source of PAHs in the inter-tidal surface sediment of the Kenting coast is the combustion of petroleum and biomass.
[Show abstract][Hide abstract] ABSTRACT: In the present study, we used zebrafish (Danio rerio) as a model to address possible effects of chronic exposure of polybrominated diphenyl ether (PBDE) flame retardants on locomotion behavior, body size, and gonad development in fish. Zebrafish were fed food dosed with PBDE-47 (control, solvent control, low, medium, and high dose groups) from 21 days post hatch (dph) to 90 dph. Fish locomotion parameters, including maximum swimming speed, total distance moved, and percent time active, were assessed using a video-based animal movement analysis system. At the end of the exposure, all fish were euthanized for length and weight measurement, and then subjected to either whole fish histological analysis or tissue PBDE-47 measurement. Survival, body size, and gonad histology were similar between the five groups. However, both total swimming distance and percent time active were negatively correlated with tissue PBDE-47 concentration and were significantly lower in the high dose group. Tissue levels of PBDE-47 in the exposed fish were comparable to that reported in previous field studies. In summary, this study showed that developmental exposure of PBDE-47 at an ecologically relevant level altered locomotion behavior without affecting body size or gonad development of zebrafish.
[Show abstract][Hide abstract] ABSTRACT: In this study, zebrafish (Danio rerio) were fed food dosed with pure PBDE-47 (2,2',4,4'-tetrabromodiphenyl ether) congener or a blank from 20 to 60 day post-hatch (dph). At 38 dph, half of the fish were sampled for body size measurements and gene expression analyzes (CYP1A1, VTG, TTR, D1, and TSH-beta). At 60 dph, body size was measured again for all fish remaining. Whole-fish histology was performed and the PBDE levels in fish were determined. PBDE treated fish was significantly smaller at 38 dph but not at 60 dph. No apparent histopathological effect was observed. In the PBDE treated fish, there was a weak induction of CYP1A1 mRNA transcription, but not of the other genes. The tissue levels of PBDE-47 were comparable to that found in other wild fish reported in the literature, indicating that our exposure level was ecologically relevant.
[Show abstract][Hide abstract] ABSTRACT: This distribution and variation of 45 polycyclic aromatic hydrocarbons (PAHs) in the waters of Kenting coral reefs were investigated by using sensitive research-grade sampling and analytical methods. The concentration levels of total PAHs (including particulate and dissolved PAHs) in the Kenting waters were relatively low, ranging from 2.2 to 34.4 ng/L. There was no significant spatial difference in PAH concentrations among the sampling stations, even between the surface and bottom waters. The fraction of dissolved PAHs on average was greater than that of particulate PAHs due to the small amount of total suspended particles. The partition coefficients between the particulate and dissolved phase (log K(oc)) were positively correlated with their log K(ow) values (r(2) = 0.67, n = 80), except for the more hydrophobic PAHs with log K(ow) values greater than 5.91. Results of principal component analysis indicate that the patterns of particulate PAH compositions were similar through the Kenting waters in the fall and winter, whereas there was a significant spatial difference between the spring and summer samples, which might be affected by a combination of land runoff and coastal currents. PAHs along the Kenting coasts were dominated by low-molecular PAHs, which have higher solubility than high-molecular PAHs. Based on isomer ratios, analysis of the source of PAHs in the Kenting coastal waters demonstrated that the PAHs come mostly from petroleum and, to a lesser degree, from combustion.
Archives of Environmental Contamination and Toxicology 10/2009; 58(3):489-98. DOI:10.1007/s00244-009-9411-y · 1.90 Impact Factor