Temporal variability of air-water gas exchange of carbon dioxide in clam and fish aquaculture ponds.

The growing trend of land-based aquaculture has heightened the significance of comprehensively assessing air-water carbon dioxide (CO2) gas exchange in these inland waters, given their potential impact on carbon neutral strategies. However, temporal variations of partial pressure of CO2 (pCO2) and CO2 flux in clam and fish aquaculture ponds were barely investigated. We assessed the water surface pCO2 in one to five months intervals by deploying a lab-made buoy in three clam ponds and three fishponds located in tropical and subtropical climates. Measurements were conducted over a 24 h period each time, spanning from April 2021 to June 2022, covering the stocking, middle, and harvesting stages of the culture cycle. Diurnal pCO2 variations were dominantly controlled by biologically driven changes in dissolved inorganic carbon and total alkalinity (~97 %), while temperature and salinity effects were minor (~3 %). Clam ponds acted as a sink of atmospheric CO2 during stocking stages and transitioned to a source during middle to harvesting stages. In contrast, fishponds acted as a source of atmospheric CO2 throughout culture cycles and CO2 flux strengthened when reaching harvesting stages. Overall, clam ponds acted as a weak sink for atmospheric CO2 (-2.8 ± 17.3 mmol m-2 d-1), whereas fishponds acted as a source (16.8 ± 21.7 mmol m-2 d-1). CO2 emission was stronger during daytime coinciding with higher windspeeds compared to nighttime in fishponds. We suggest incorporating high temporal resolution measurements to account for diurnal and culture-stage variations, enabling more accurate estimates of air-water CO2 flux in aquaculture ponds. Moreover, the findings of this study highlight the importance of feeding, aeration, and biological activities (photosynthesis, remineralization, and calcification) in controlling the air-water CO2 flux in aquaculture ponds and such information can be used in implementing better strategies to achieve carbon neutral goals.

Dyngo-4a Induces Neuroblastoma Cell Differentiation Through The AKT and ERK1/2 Pathway.

AIM: The aim of the study is to check whether dyngo-4a can inhibit neuroblastoma (NB) proliferation and induce NB cell differentiation Background: Dynamin plays a role in regulating neurotransmission, signaling pathways, nutrient uptake, and pathogen infection, enhancing cell proliferation, tumor invasion, and metastasis. Studies have reported that dyngo-4a, a dynamin inhibitor, can be used to identify potential biomarkers and promising novel therapeutic targets for cancer treatment. OBJECTIVE: To our knowledge, no published reports are showing that dynamin inhibitors can reduce NB cell proliferation and induce differentiation. In this study, we report that dyngo-4a can inhibit NB proliferation and induce NB cell differentiation. METHODS: In this study, mouse neuroblastoma (Neuro-2a) cells were cultured in the presence or absence of dyngo-4a or retinoic acid (RA), or in the presence of both dyngo-4a and RA, or in the presence of sequential administration of dyngo-4a and RA to compare the effects on the inhibition of cell proliferation and effects on neuroblastoma cell differentiation induction. The neural cell markers, Nestin and Tuj 1 (Neuron-specific class III beta-tubulin), were used to demonstrate that the differentiated cells have neuronal cell features. The phosphorylation of Protein Kinase B (AKT), extracellular signalregulated kinases1/2 (ERK1/2), and epidermal growth factor receptor (EGFR) were determined to examine the potential mechanisms of induced differentiation. RESULTS: Dyngo-4a or RA or dyngo-4a with subsequent RA administration induced Neuro-2a cell differentiation. However, RA with subsequent dyngo-4a administration results in almost total death of the Neuro-2a cells. The differentiation rate induced by dyngo-4a was significantly higher than the rate by RA treatment (72.5 ± 1.4% vs. 52.9 ± 3.1% with neuron features, P<0.05; 39.0 ± 0.8% vs. 29.9 ± 1.8% for axons under light microscopy, p<0.05). The differentiation rate of cells treated with dyngo-4a first, followed by RA, was greater than when they were added together (74.8 ± 3.8% vs. 10.6 ± 3.6%; 45.5 ± 1.6% vs. 12.4 ± 0.6%, p<0.01). Co-administration of dyngo-4a and RA at the same time diminished differentiation efficacy significantly. Dyngo-4a induced Neuro-2a cell differentiation and increased Tuj-1 positive staining by the 6th day post- treatment. Dyngo-4a also inhibited Neuro-2a cell proliferation in a dose-dependent manner. Regarding the mechanism, dyngo-4a treatment showed a significant increase in p-AKT and p-ERK1/2 but not in p-EGFR. CONCLUSION: At a level comparable to RA, dynamin inhibition with dyngo-4a lowers proliferation and causes differentiation of Neuro-2a mouse NB cells in vitro. The AKT pathway is activated by dynago- 4a, which results in differentiation. The combination of RA with dynago-4a reduces the efficiency of differentiation. The application of dynago-4a followed by RA, on the other hand, enhances the differentiating effect, implying alternative mechanistic roles in the process.

Potential impacts of Washington State's wildfire worker protection rule on construction workers.

Driven by climate change, wildfires are increasing in frequency, duration, and intensity across the Western United States. Outdoor workers are being exposed to increasing wildfire-related particulate matter and smoke. Recognizing this emerging risk, Washington adopted an emergency rule and is presently engaged in creating a permanent rule to protect outdoor workers from wildfire smoke exposure. While there are growing bodies of literature on the exposure to and health effects of wildfire smoke in the general public and wildland firefighters, there is a gap in knowledge about wildfire smoke exposure among outdoor workers generally and construction workers specifically-a large category of outdoor workers in Washington totaling 200,000 people. Several data sources were linked in this study-including state-collected employment data and national ambient air quality data-to gain insight into the risk of PM2.5 exposure among construction workers and evaluate the impacts of different air quality thresholds that would have triggered a new Washington emergency wildfire smoke rule aimed at protecting workers from high PM2.5 exposure. Results indicate the number of poor air quality days has increased in August and September in recent years. Over the last decade, these months with the greatest potential for particulate matter exposure coincided with an annual peak in construction employment that was typically 9.4-42.7% larger across Washington counties (one county was 75.8%). Lastly, the 'encouraged' threshold of the Washington emergency rule (20.5 µg m-3) would have resulted in 5.5 times more days subject to the wildfire rule on average across all Washington counties compared to its 'required' threshold (55.5 µg m-3), and in 2020, the rule could have created demand for 1.35 million N-95 filtering facepiece respirators among construction workers. These results have important implications for both employers and policy makers as rules are developed. The potential policy implications of wildfire smoke exposure, exposure control strategies, and data gaps that would improve understanding of construction worker exposure to wildfire smoke are also discussed.

Data on isotopic niche differentiation in benthic consumers from shallow-water hydrothermal vents and nearby non-vent rocky reefs in northeastern Taiwan.

This paper presents data on carbon and nitrogen stable isotopes in benthos from shallow-water hydrothermal vents (SV) and nearby non-vent rocky reefs (NV) located in northeastern Taiwan, which is related to the article "Isotopic niche differentiation in benthic consumers from shallow-water hydrothermal vents and nearby non-vent rocky reefs in northeastern Taiwan" [1]. Field sampling work was conducted in July 2009 and July-August 2010 to collect sediment organic matters (SOM), zooplankton, and benthos for carbon and nitrogen stable isotopic analyses. Scuba divers collected macrobenthos, seawater, and surface sediments (0-2 cm). The collection of zooplankton was by a North Pacific standard net and trawled vertically. Testing samples were lyophilized before grounding by a mortar and pestle. For carbon and nitrogen isotope analyses, approximately 1 mg of powder was weighed and encapsulated in a tin capsule. Analyses were performed at the stable isotope laboratory at the University of California at Davis using an Integra Mass Spectrometer elemental analyzer (PDZ Europa, Sandbach, UK). The information is presented as 187 and 53 unprocessed data points from SV and NV, which incorporates δ13C and δ15N values (‰) of sediment, zooplankton, and benthos' tissue samples. Data from SOM provides information about chemosynthetic activity in SV sites. These data can be used to correlate food sources of consumers inhabiting shallow-water hydrothermal vent and rocky reef ecosystems in subtropical regions.

Reproduction and Early Juvenile Growth of the Giant Clams Tridacna noae and Tridacna maxima in Taiwan.

The reproductive cycle, larval development, and juvenile growth of Tridacna noae and Tridacna maxima were investigated to improve their hatchery production for conservation and commercial use in Taiwan. To study the giant clam reproductive cycle, hypodermic extraction of oocytes from T. noae and T. maxima was conducted in Dongsha and Kenting, Taiwan, from March 2013 to May 2014; ripe eggs were observed in both species from March to August. There was no apparent correlation between reproduction and water temperature. Artificial fertilization was successfully conducted in T. maxima, T. noae, and a hybrid of T. maxima♀/T. noae♂. The diameter of fertilized eggs was 99.0 ± 8.1, 113.8 ± 18.5, and 116.3 ± 6.2 µm, respectively. On day 6, the hybrid died. Tridacna maxima grew more than T. noae in both 1-and 10-month-old juveniles. The juvenile growth of T. noae was compared between the artificial breeding sites of Penghu and Linbian, which represent the main ornamental aquatic animal culture areas of Taiwan. Starting with individuals with a shell length of 15.9 ± 2.5 mm (265 days old), the juveniles observed in Linbian were significantly larger than those in Penghu, i.e., 26.6 ± 3.6 mm on day 307 vs. 18.6 ± 2.9 mm on day 321 (p < 0.001). This might be linked to the differences in local water temperatures between the two locations, i.e., 20.3-27.0°C vs. 16.9-23.9°C, respectively. These results can be used to further research ways to maximize spat production and minimize giant clam operational costs.

Evidence for Fossil Fuel PM1 Accumulation in Marine Biota.

When fine particulates such as those with a diameter of approximately 1 µm (particulate matter, PM1) are released from fossil fuel combustion into the air, they warm the atmosphere and contribute to millions of premature deaths in humans each year. Considerable quantities of PM1 eventually enter the oceans as suspended particulates, yet subsequent removal mechanisms are poorly understood. In fact, the presence of PM1 in marine biota has never been reported. Since sea anemones are opportunistic suspension feeders, they are anticipated to incorporate and accumulate PM1 in their bodies. By histological examination, PM1 was detected in 21 of the 22 sea anemones collected from Taiwan and Southeast China, with a depth of intertidal zone to 1000 m. PM1, if present, was always detected in endodermal layers and had the same dominant color (i.e., black, brown, or green) in different species from the same site. The bioaccumulation factor of PM1 in sea anemones was approximately 5-7 orders of magnitude. Based on radioisotope 14C results, the contribution of fossil fuel source PM1 was 8-24%. Regardless of PM1's color, S and Fe were commonly detected by scanning electron microscopy and energy-dispersive spectrometry (SEM-EDS), suggesting anthropogenic sources. Furthermore, a maternal transfer of materials was suggested based on the existence of PM1 in sea anemone eggs and in brooding and released juveniles. The significance of PM1 accumulation by biota in aquatic ecosystems and the potential risk to living organisms via food webs warrant further investigation.

Rhodobacter sphaeroides Extract Lycogen™ Attenuates Testosterone-Induced Benign Prostate Hyperplasia in Rats.

Benign prostate hyperplasia (BPH) is one of the most common urological problems in mid-aged to elderly men. Risk factors of BPH include family history, obesity, type 2 diabetes, and high oxidative stress. The main medication classes for BPH management are alpha blockers and 5α-reductase inhibitors. However, these conventional medicines cause adverse effects. Lycogen™, extracted from Rhodobacter sphaeroides WL-APD911, is an anti-oxidant and anti-inflammatory compound. In this study, the effect of Lycogen™ was evaluated in rats with testosterone-induced benign prostate hyperplasia (BPH). Testosterone injections and Lycogen™ administration were carried out for 28 days, and body weights were recorded twice per week. The testosterone injection successfully induced a prostate enlargement. BPH-induced rats treated with different doses of Lycogen™ exhibited a significantly decreased prostate index (PI). Moreover, the Lycogen™ administration recovered the histological abnormalities observed in the prostate of BPH rats. In conclusion, these findings support a dose-dependent preventing effect of Lycogen™ on testosterone-induced BPH in rats and suggest that Lycogen™ may be favorable to the prevention and management of benign prostate hyperplasia.

The Functional Haplotypes of CHRM3 Modulate mRNA Expression and Associate with Bladder Cancer among a Chinese Han Population in Kaohsiung City.

Bladder cancer is one of the major cancer types and both environmental factors and genetic background play important roles in its pathology. Kaohsiung is a high industrialized city in Taiwan, and here we focused on this region to evaluate the genetic effects on bladder cancer. Muscarinic acetylcholine receptor M3 (CHRM3) was reported as a key receptor in different cancer types. CHRM3 is located at 1q42-43 which was reported to associate with bladder cancer. Our study attempted to delineate whether genetic variants of CHRM3 contribute to bladder cancer in Chinese Han population in south Taiwan. Five selected SNPs (rs2165870, rs10802789, rs685550, rs7520974, and rs3738435) were genotyped for 30 bladder cancer patients and 60 control individuals and genetic association studies were performed. Five haplotypes (GTTAT, ATTGT, GCTAC, ACTAC, and ACCAC) were found significantly associated with low CHRM3 mRNA level and contributed to increased susceptibility of bladder cancer in Kaohsiung city after rigid 10000 consecutive permutation tests. To our knowledge, this is the first genetic association study that reveals the genetic contribution of CHRM3 gene in bladder cancer etiology.

Towards the small and the beautiful: a small dibromotyrosine derivative from Pseudoceratina sp. sponge exhibits potent apoptotic effect through targeting IKK/NFκB signaling pathway.

A dibromotyrosine derivative, (1'R,5'S,6'S)-2-(3',5'-dibromo-1',6'-dihydroxy-4'-oxocyclohex-2'-enyl) acetonitrile (DT), was isolated from the sponge Pseudoceratina sp., and was found to exhibit a significant cytotoxic activity against leukemia K562 cells. Despite the large number of the isolated bromotyrosine derivatives, studies focusing on their biological mechanism of action are scarce. In the current study we designed a set of experiments to reveal the underlying mechanism of DT cytotoxic activity against K562 cells. First, the results of MTT cytotoxic and the annexin V-FITC/PI apoptotic assays, indicated that the DT cytotoxic activity is mediated through induction of apoptosis. This effect was also supported by caspases-3 and -9 activation as well as PARP cleavage. DT induced generation of reactive oxygen species (ROS) and the disruption of mitochondrial membrane potential (MMP) as indicated by flow cytometric assay. The involvement of ROS generation in the apoptotic activity of DT was further corroborated by the pretreatment of K562 cells with N-acetyl-cysteine (NAC), a ROS scavenger, which prevented apoptosis and the disruption of MMP induced by DT. Results of cell-free system assay suggested that DT can act as a topoisomerase II catalytic inhibitor, unlike the clinical anticancer drug, etoposide, which acts as a topoisomerase poison. Additionally, we found that DT treatment can block IKK/NFκB pathway and activate PI3K/Akt pathway. These findings suggest that the cytotoxic effect of DT is associated with mitochondrial dysfunction-dependent apoptosis which is mediated through oxidative stress. Therefore, DT represents an interesting reference point for the development of new cytotoxic agent targeting IKK/NFκB pathway.

Cytotoxic sesterterpenoids from a sponge Hippospongia sp.

One new pentacyclic sesterterpene, hippospongide A (1), and one new scalarane sesterterpenoid, hippospongide B (2), along with six previously reported known scalarane-type sesterterpenes (3-8), were isolated from a sponge Hippospongia sp. The structures of these compounds were elucidated on the basis of their spectroscopic data and comparison of the NMR data with those of known analogues. These metabolites are the first pentacyclic sesterterpene and scalarane-type sesterterpenes to be reported from this genus. Compounds 3-5 exhibited significant cytotoxicity against DLD-1, HCT-116, T-47D and K562 cancer cell lines.

Impacts of human activities on coral reef ecosystems of southern Taiwan: a long-term study.

In July 2001, the National Museum of Marine Biology and Aquarium, co-sponsored by the Kenting National Park Headquarters and Taiwan's National Science Council, launched a Long-Term Ecological Research (LTER) program to monitor anthropogenic impacts on the ecosystems of southern Taiwan, specifically the coral reefs of Kenting National Park (KNP), which are facing an increasing amount of anthropogenic pressure. We found that the seawater of the reef flats along Nanwan Bay, Taiwan's southernmost embayment, was polluted by sewage discharge at certain monitoring stations. Furthermore, the consequently higher nutrient and suspended sediment levels had led to algal blooms and sediment smothering of shallow water corals at some sampling sites. Finally, our results show that, in addition to this influx of anthropogenically-derived sewage, increasing tourist numbers are correlated with decreasing shallow water coral cover, highlighting the urgency of a more proactive management plan for KNP's coral reefs.

One-step microwave-assisted headspace solid-phase microextraction for the rapid determination of synthetic polycyclic musks in oyster by gas chromatography-mass spectrometry.

A rapid, simple and solvent-free procedure was developed for the determination of synthetic polycyclic musks in oyster samples by using one-step microwave-assisted headspace solid-phase microextraction (MA-HS-SPME) and gas chromatography-mass spectrometry (GC-MS). Two commonly used synthetic polycyclic musks, galaxolide (HHCB) and tonalide (AHTN), were selected in the method development and validation. The parameters (microwave irradiation power, extraction time, amount of water added, pH value and addition of NaCl) affecting the extraction efficiency of analytes from oyster slurry were systematically investigated and optimised. The best extraction conditions were achieved when the oyster tissue mixed with 10-mL deionised water (containing 3g of NaCl in a 40-mL sample-vial) was microwave irradiated at 80 W for 5 min. The limit of quantification (LOQ) was 0.1 ng/g in 5-g of wet tissue. The good precision and accuracy of one-step MA-HS-SPME coupled with GC-MS for the determination of trace level of AHTN in oyster samples was also demonstrated.

Cytotoxic C21 and C22 terpenoid-derived metabolites from the sponge Ircinia sp.

One novel C21 terpenoidal natural product, ircinolin A (2), two new C22 furanoterpene metabolites, 15-acetylirciformonin B (3) and 10-acetylirciformonin B (4), and two known compounds, irciformonin B (1) and irciformonin F (5), were isolated from the sponge Ircinia sp. The structures of these compounds were elucidated on the basis of their spectroscopic data. Moreover, the absolute configuration of 1 was determined by Mosher's method. Among these metabolites, 2 is the first C21 terpenoid-derived metabolite to be reported from this genus. Compounds 1 and 3-5 exhibited significant cytotoxic activity against K562, DLD-1, HepG2, and Hep3B cancer cell lines.

Distribution and accumulation of organotin species in seawater, sediments and organisms collected from a Taiwan mariculture area.

The present study was undertaken to evaluate the distribution and accumulation of tributyltin (TBT) and triphenyltin (TPhT) in seawater, sediments and selected organisms from a cage mariculture area in southern Taiwan, Hsiao Liouchiou Island. Our results show that ΣOTs were found in concentrations as high as 196 ng/L in seawater collected from the sites in Pai-Sa harbor, and up 1040 ng/g dry wt. in sediments dredged from sites within Da-Fu harbor. Also, ΣOTs concentrations of 859 ng/g dry wt. were observed in the liver of cobia (Rachycentron canadum) from mariculture cages. As most published studies have focused on the acute toxicity and bioaccumulation of organotins in mussels, the effects of organotins on cobia and other marine fauna are still poorly understood. This study highlights the significance of ΣBTs accumulation in cobia, as well as in the sediments and seawater surrounding their culture facilities.

17ß-Estradiol protects against acetaminophen-overdose-induced acute oxidative hepatic damage and increases the survival rate in mice.

Acetaminophen overdose causes acute liver injury or even death in both humans and experimental animals. We investigated the effect of 17ß-estradiol against acetaminophen-induced acute liver injury and mortality in mice. Male mice were given acetaminophen (p-acetamidophenol; 300 mg/kg; orally) to induce acute liver injury. Acetaminophen significantly increased the levels of aspartate transaminase, alanine transaminase, myeloperoxidase, lipid peroxidation, and glutathione reductase, but it decreased superoxide dismutase, catalase, and glutathione. In addition, acetaminophen-induced mortality began 4h post-treatment, and all mice died within 9h. 17ß-Estradiol (200 µg/kg; i.p.) protected against acetaminophen-induced oxidative hepatic damage by inhibiting neutrophil infiltration and stimulating the antioxidant defense system. However, 17ß-estradiol did not affect acetaminophen-induced glutathione depletion or increased glutathione reductase activity. We conclude that 17ß-estradiol specifically attenuates acute hepatic damage and decreases mortality in acetaminophen-overdosed male mice.

Aquatic organotin pollution in Taiwan.

The current status of aquatic organotin pollution in Taiwan is reviewed. In freshwater sediments and biota, especially in rice-field related habitats, phenyltins (PTs) were dominant among the organotin pollutants, whereas butyltins (BTs) were usually predominant in marine environments. Among the marine habitats, contamination levels were found to be in the descending order of harbour and estuary>fish cultural site>coastal>offshore>coral reefs. Imposex snails were observed in all the sampling years (1990-2003). Meanwhile, organotin concentrations were greater in winter than those in summer, whereas proportions of PTs were much higher in summer than in winter. Due to the lack of continuous monitoring data, the effectiveness of the ban on TPT usage in agriculture in 1999 and the prohibition of TBT use on small boats in 2003 is still not known.

Effect of sesame oil against acetaminophen-induced acute oxidative hepatic damage in rats.

Acetaminophen (APAP) overdose causes acute liver injury or even death in both humans and experimental animals. We investigated the effect of sesame oil on APAP-induced acute liver injury. Male Wistar rats were given APAP (1,000 mg/kg; orally) to induce acute liver injury. Acetaminophen significantly increased aspartate transaminase, alanine transaminase, lipid peroxidation, and superoxide anion and hydroxyl radical generation levels; it also induced glutathione depletion. Sesame oil (8 mL/kg; orally) did not alter the gastric absorption of APAP, but it inhibited all the parameters altered by APAP and protected the rats against APAP-induced acute liver injury. We hypothesize that sesame oil maintained the intracellular glutathione levels, reduced reactive oxygen species levels, and inhibited lipid peroxidation in rats with APAP-induced acute liver injury.

Imposex in the golden apple snail Pomacea canaliculata in Taiwan.

The golden apple snail Pomacea canaliculata (Lamarck, 1822) was introduced into Taiwan intentionally in the early 1980s and has become a recurring pest that seriously threatens aquatic crops. In this study, a field description of imposex with a developed penis sheath and penis in female golden apple snails from crop/domestic wastewater drainage sites and a six-order river is presented for the first time. Based on the five field collections and the aquarium group, the vas deferens sequence (VDS) of P. canaliculata in imposex development was categorized into four stages, i.e., stage 0: without male genital system; stage 1: with rudimentary penis; stage 2: with rudimentary penis and penis sheath; and stage 3: the rudimentary penis developing into penis pouch and penis. The VDS indices varied between 1.07 and 2.82 and were lowest in the aquarium group and Yuanlin2. Regarding the severity of imposex, the aquarium group was less pronounced, as illustrated by the length of penis sheath and penis length, than the field collections (p<0.05). In respect of the penis length, males of the most imposex-affected site were up to 15% shorter than that of the aquarium group. Negative correlations between male penis length and female imposex characters (i.e., penis length and penis sheath length) were also observed.

Occurrence and seasonal variation of alkylphenols in marine organisms from the coast of Taiwan.

The occurrence and distribution of alkylphenols (APs, i.e., 4-tert-octylphenol (4-t-OP) and 4-nonlyphenol isomers (4-NP)) in oysters (Crassostrea gigas), snails (Thais clavigera), coastal water and coastal sediments of the western coast of southern Taiwan are investigated. Alkylphenols were present in all matrices of interest: in water, ranging from 61 to 370 ng/l, in sediments, ranging from 27 to 190 ng/g, and in biota samples (i.e., oyster and snail), ranging from 20 to 5190 ng/g. Statistical analysis indicated that the probability distribution of most determined concentrations in oyster and snail samples was log-normal distribution. The bioaccumulation of APs resulted in a seasonal variation with respect to their compositions and concentrations in oyster and snail samples. For oysters, concentrations of APs in winter exceeded those in summer. In contrast, those in snails in summer exceeded those in winter. Estimated biomagnification factors of APs from snails to oysters ranged from 1.4 to 4.3 in summer, and 0.5 to 0.8 in winter on the dry weight basis. The results suggested that seasonally mediated physiological changes, such as dilution caused by growth, biotransformation and metabolism, may affect the bioaccumulation of APs in according to season and organism.

Analysis of perfluorooctanesulfonate and related fluorochemicals in water and biological tissue samples by liquid chromatography-ion trap mass spectrometry.

A method for the determination of perfluorinated compounds (PFCs) in various water and biological tissue samples was developed and validated. The contents of selected PFCs (i.e., perfluorooctanesulfonate (PFOS), perfluorooctanoate (PFOA) and perfluorodecanoate (PFDA)) in water samples were extracted by the C(18) solid-phase extraction (SPE). The biological tissue samples (frozen-dried fish and oysters) were simply extracted by liquid-solid extraction with MTBE and adding tetrabutylammonium hydrogensulfate (TBA) as an ion-pairing reagent. The analytes were then identified and quantitated by liquid chromatography-ion trap negative electrospray mass spectrometry (LC-ESI ion-trap-MS). Limits of quantitation (LOQ) were established between 0.5 and 6 ng/l in 250 ml of water sample, while 5-50 ng/g (dry weight) for biological tissue sample. Intrabatch and interbatch precision with their accuracy at two concentration levels were also investigated. Precision for these three PFCs, as indicated by RSD, proved to be less than 11 and 17%, respectively. The total contents of PFOA, PFOS and PFDA were detected in concentrations of up to 400 ng/l in various water samples, while up to 1,100 ng/g in fish and oyster samples. PFOA and PFDA was the major PFCs detected in water samples and biological tissue samples, respectively.