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1.
Mar Pollut Bull ; 124(2): 929-937, 2017 Nov 30.
Article in English | MEDLINE | ID: mdl-28669477

ABSTRACT

The effects of increasing CO2 concentrations and temperature on microalgal assemblages were examined in Taiwan using mesocosms that simulate coral reef ecosystem. We assessed changes in abundance and diversity of benthic algae grown at 25°C and 28°C, under ambient (~400µatm) and at high CO2 conditions (800-1000µatm). Total alkalinity, pCO2, and the aragonite saturation state, were all significantly different between control and high CO2 treatments in both temperature treatments. Chl a concentration increased significantly in CO2-treated groups at 25°C, but benthic microalgal abundance was not significantly different. The number of microalgal species and the microalgal community structure did not differ between control and CO2-treated groups at both temperatures. Our results suggest that increasing CO2 may boost benthic microalgal primary productivity if sufficient nutrients are available, although site-specific responses are difficult to predict.


Subject(s)
Biodiversity , Carbon Dioxide/analysis , Chlorophyll/metabolism , Hot Temperature , Microalgae/physiology , Chlorophyll A , Taiwan
2.
Article in Chinese | MEDLINE | ID: mdl-28511312

ABSTRACT

Objective: To investigate the peak time and peak area of elements in cadmium telluride quantum dots (CdTe QDs) using size exclusion chromatography-high-performance liquid chromatography-inductively coupled plasma mass spectrometry, as well as the biological stability of CdTe QDs in vivo and in vitro. Methods: Transmission electron microscope and ultraviolet fluorescence were used for characterization and synthesis of water-soluble CdTe QDs, and CdTe QDs were added to double-distilled water, mobile phase, or bovine serum medium to observe the change in stability after different periods of time. CdTe QDs were injected into the vein of mice, and the changes in the morphology of CdTe QDs in serum and the liver were measured at 1, 24, and 72 hours after exposure. Size exclusion chromatography-high-performance liquid chromatography was used for the elution of the compounds in the solution based on their volume, and then inductively coupled plasma mass spectrometry was performed for the eluent. The flow time of (114)Cd and (130)Te and molar ratio were used for qualitative analysis of CdTe QDs, and the peak area was used to judge whether CdTe QDs were degraded. Results: CdTe QDs were diluted to a concentration of 0.5 mmol/L with double-distilled water and then placed in a dark place at room temperature; CdTe QDs were completely degraded after 60 minutes. CdTe QDs were diluted to a concentration of 0.005 mmol/L with a mobile phase, and the peak of CdTe QDs was not detected. After CdTe QDs were placed in a dark place at room temperature for 48 hours at a concentration of 0.005 mmol/L in bovine serum mediumin vitro, the peak area of (114)Cd was 6179841-7346084, and the peak area of (130)Te was 1077913-1191066. CdTe QDs had the highest peak area at 1 hour after exposure, and the peak areas of (114)Cd and (130)Te were 18183894 and 25187987, respectively. CdTe QDs were quickly degraded in the liver; at 1 hour after exposure, the degradation products of CdTe QDs containing Cd were observed in liver tissue homogenate, and CdTe QDs were largely degradedat 24 hours. Conclusion: This method can be used to investigate the biological stability of CdTe QDs. CdTe QDs are degraded in the liver and produce Cd(2+), which may cause toxic reaction.


Subject(s)
Cadmium Compounds/chemistry , Chromatography, High Pressure Liquid/methods , Mass Spectrometry/methods , Quantum Dots/chemistry , Animals , Cadmium , Cattle , Mice , Microscopy, Electron, Transmission , Spectrophotometry, Ultraviolet , Water
3.
Chemosphere ; 44(4): 833-41, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11482676

ABSTRACT

Since October 1994, a long-term program of Asia/Pacific Mussel Watch: Taiwan Regional Studies has been carried out. The results indicate that trace metal contents in mollusca varied among 30 different species and the environments (water and sediments) along the Taiwan coast. The orders of bioaccumulation of trace metals in mollusca were: Cu (over 200 microg/g), Thais clavigera > Isognomon legumen > Clibanarius rivescens > Crassostrea gigas; Zn (over 700 microg/g), Moruta granulata > C. gigas > Asiatica cypraea arabica > T. clavigera; Cd (over 5 microg/g), Trochus hanleyanus > Acanthopleura japonica > Nerita albicilla > Patella flexuosa; Pb (over 2 microg/g), P. flexuosa > C. gigas > T. hanleyanus > T. clavigera > C. gigas > Capiyulum mitella; Ni (over 10 microg/g), Meretrix lusoria > Philine sp. > Littoraria scabra > Tridacna squamosa > T. hanleyanus; Cr (over 30 microg/g), Littoraria undulata > T. hanleyanus > N. albicilla > Nerita chamaelor > M. granulata; As (over 20 microg/g), Perna viridis > L. scabra; and Sn (over 5 microg/g), P. viridis > L. undulata> C. mitella> C. gigas. Their seasonal and regional variations as well as their correlation are evaluated and discussed.


Subject(s)
Geologic Sediments/chemistry , Metals, Heavy/pharmacokinetics , Mollusca/chemistry , Trace Elements/pharmacokinetics , Water Pollutants/analysis , Animals , Environmental Monitoring , Metals, Heavy/analysis , Tissue Distribution , Trace Elements/analysis
4.
Environ Pollut ; 110(2): 207-15, 2000 Nov.
Article in English | MEDLINE | ID: mdl-15092835

ABSTRACT

This study presents the distribution of Cu, Zn, Pb, Cd, Hg and As in various marine organisms collected along the western coast of Taiwan from 1991 to 1998, and also evaluates the time variation of Cu in oysters before (1980-85) and after (1986-98) the "green oyster" incident. The results show that relatively high geometric mean (GM) concentrations of Cu, Zn, Pb, Cd, As and Hg were generally found in Crassostrea gigas (Cu=229 microg/g, Zn=783 microg/g), Gomphina aeguialtera (Pb=30.3 microg/g), Tegillarca granosa (Cd=2.85 microg/g), Thais clavigera (As=96.9 microg/g) and Parapenaeopsis cornuta (Hg=1.35 microg/g), respectively. Especially, maximum Cu and Zn concentrations (GM=229 and 783 microg/g, respectively) in oysters (C. gigas) from different culture areas were much higher than those of the other organisms by about 1.13-458 and 2.40-63.7 times, respectively. Similarly, rock-shells (Thais clavigera) had a high capacity for accumulating Cu (GM=202 microg/g) and Zn (GM=326 microg/g) under the same physico-chemical conditions. The highest GM Cu and Zn concentrations of 1108 (range from 113 to 2806) and 1567 (range from 303 to 3593) microg/g were obtained in oysters from the Hsiangshan coastal area, one of the most important oyster culture areas in Taiwan. However, the highest GM Cd and As concentrations of 6.82 and 19.3 microg/g were found in oysters from the Machu Islands. Mean Cu concentrations in the oysters from the Erhjin Chi estuary declined from 2194+/-212 microg/g in 1986-90 to 545 microg/g (GM) in 1991-96. In the Hsiganshan area, GM Cu concentrations of 909 microg/g (1991-96) and 1351 microg/g (1997-98) in oysters were significantly higher than those of 201 microg/g (1980-85) and 682 microg/g (1986-90). The gradually increasing levels of Cu and Zn in the oysters from the Hsiangshan area have been observed year by year.

5.
Fa Yi Xue Za Zhi ; 15(1): 17-8, 63, 1999 Feb.
Article in Chinese | MEDLINE | ID: mdl-12536391

ABSTRACT

A solid-phase extraction method of morphine from urine and blood has introduced. The effect of 5 SPE columns, 3 eluents and pH on morphine recovery has been investigated systematically. Derivative GC was used as a method of detection. The result showed that the column and the eluent of such as GDX-301, GDX-403 and C18 chloroform:isopropanol (9:1) had good behaviors to extraction of morphine. When GDX-301 was used as a sorbent, the recovery of morphine from urine was above 90% at pH 9, then went down with the increase of pH. While the recovery from blood was growing with the increase of pH, which reached above 90% in strong alkaline. The extraction method is simple, inexpensive, efficient and reproducible, which provides an effective and practical method to extract morphine and similar illicit drugs from biological fluids.


Subject(s)
Morphine/blood , Morphine/urine , Substance Abuse Detection/methods , Chromatography, Gas , Humans , Indicators and Reagents
6.
Arch Environ Contam Toxicol ; 32(4): 456-61, 1997 May.
Article in English | MEDLINE | ID: mdl-9175516

ABSTRACT

This study presents the distribution of arsenic (As), copper (Cu), and zinc (Zn) in various seafoods-oysters (Crassostrea gigas), false fusus (Hemifuscus tuba), venus clams (Cyclina sineasis), green mussels (Perna viridis), blood clams (Arca granosa), flounders (Psettodes erumei), and rock-shells (Thais clavigera) collected from the Putai coast of the black-foot disease (BFD) area in Taiwan. Special attention is paid to evaluate the relationships among As, Cu, and Zn and effect of body size on metal concentration in Thais clavigera. Maximum Zn and Cu geometric mean (GM) concentrations (GM = 615 and 376 microg/g, dry wt, respectively) are found in oysters (Crassostrea gigas), and the values are much higher than those of the other organisms by about 1.7-208 and 1.8-375 times, respectively. Similarly, Thais clavigera has a high capacity for accumulating Cu and Zn collected from the same location. One interesting point is that relatively high As concentrations (GM = 65.7 microg/g, dry wt) in Thais clavigera are found as compared with those in other organisms (range from GM = 2.37 to 40.2 microg/g, dry wt). The As concentrations are significantly higher in Thais clavigera (1.62-27.7 times) than those in other organisms (p < 0.05), except for the false fusus (Hamifuscus tuba). A linear regression analysis shows a significant increase in Zn concentration with increasing Cu concentration in Thais clavigera. On the other hand, the As concentration is correlated with Cu and Zn concentrations (r = 0.77 and 0.77, respectively; p < 0.05) in Thais clavigera. Double logarithmic plots of metal content and concentration against dry-body weight and shell length show linear relationships. The result indicates that large individuals have higher contents of Cu, Zn and As, and have slopes of 1.58, 1.38, and 1.34, respectively. In addition, metal concentrations against shell length for all animal sizes also indicate that Cu, Zn and As have slopes of 1.92, 1.18, and 1.11, respectively. In conclusion, Thais clavigera has a high capactiy for accumulating As, Cu, and Zn and is a potential bioindicator for monitoring As, Cu and Zn.


Subject(s)
Arsenic/analysis , Copper/analysis , Mollusca/chemistry , Seawater/chemistry , Zinc/analysis , Animals , Taiwan , Water Pollutants, Chemical/analysis , Water Pollution, Chemical/analysis
7.
Environ Pollut ; 80(3): 223-30, 1993.
Article in English | MEDLINE | ID: mdl-15091841

ABSTRACT

The species of copper and zinc, such as bioexchangeable, skeletal, easily reducible (Fe and Mn oxides), moderately reducible (crystalline Mn oxide), organic combined with sulfides, and detritus with minerals, in mud and sand, separated from the surface Antarctic Ocean and the Taiwan Erhjin Chi coastal (including river and estuarine) sediments, have been analyzed by sequential leaching methods. Results show that in the Antarctic Ocean sediments, high concentrations of total copper (128 mg/kg) and zinc (458 mg/kg) were found in the high mud (99.09%) content samples compared with the low concentrations of total copper (83.8 mg/kg) and zinc (288 mg/kg) in low mud (51.69%) content samples. High concentrations of copper, zinc, manganese and iron are possibly due to the characteristics of manganese nodules, in which the species of copper and zinc are mainly contained in the crystalline Mn oxide phase. In the Taiwan Erhjin Chi coastal sediments, the total copper and zinc concentrations in mud and sand vary with season and location. High values were generally observed in the river sediments during the dry season, and low values were in the estuarine and coastal sediments during the heavy rainy season. High percentages of copper (as high as 49.4%) and zinc (as high as 76.7%) in mud and sand were in the bioexchangeable phase including the skeletal phase. This result might be correlated with the problems arising from human impact on copper and zinc as well as sewage pollution in Taiwan. In the organic combined phase, biogenic particulate matter related to higher primary productivity in the Antarctic Ocean is also discussed.

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