• Fisheries and Aquatic Sciences
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• 제13권3호
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• pp.244-253
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• 2010

The quality of marine sediments from the industrialized coastal areas of Korea (Ulsan Bay, Masan Bay, and artificial Lake Shihwa) was investigated using a bacterial bioluminescence toxicity test. Sediment toxicity results were compared with the levels of chemical contamination (trace metals, organic wastewater markers, acid volatile sulfides, total organic carbon). Effective concentration 50% (EC50) of sediments ranged from 0.014 to 1.126 mg/mL, which is comparable to or lower than values in contaminated lakes, rivers, and marine sediments of other countries. Sediment reference index (SRI) ranged from 13 to 1044, based on the EC50 of the negative control sample. Mean average SRI values in Masan Bay and Lake Shihwa were approximately 8 and 9 times as high as that in Ulsan Bay, indicating higher sediment toxicity and greater contamination in the two former regions. Sediment toxicity were strongly associated with the concentrations of some chemicals, suggesting that this test may be useful for determining potential chemical contamination in sediments.

• 한국수산과학회지
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• 제52권3호
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• pp.268-273
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• 2019

This study evaluated acute nitrate nitrogen ($NO_3-N$) toxicity in juvenile blackhead seabream Acanthopagrus schlegelii. Seventy juveniles (Trial A, $7.1{\pm}0.6g$) and nine juveniles (Trial B, $71.3{\pm}3.5g$) per 70 L tank were exposed to $NO_3-N$ concentrations of 0, 500, 1500, 2500, 3500, and 4500 mg/L and 0, 600, 1200, 1800, 2400, and 3000 mg/L, respectively, in triplicate for 7 days. In Trial A, all fish exposed to 3500 and $4500mg\;NO_3-N/L$ died within 48 h; in Trial B, all fish exposed to $3000\;NO_3-N/L$ died after 120 h. The $96\;LC_{50}$ and $168\;LC_{50}$ were 2505 and $1806mg\;NO_3-N/L$, respectively, in Trial A, and 2663 and $2377mg\;NO_3-N/L$ in Trial B. Large juveniles were more resistant to $NO_3-N$ than small juveniles. The results of acute $NO_3-N$ toxicity studies provide important data for subsequent chronic toxicity studies.

• Fisheries and Aquatic Sciences
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• 제25권8호
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• pp.417-428
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• 2022

This study aimed to determine the antibacterial activity and toxicity of methanol and hexane extracts of Halymenia durvillei red seaweed which were found abundantly in Kayangan island, South Sulawesi. The antibacterial activity of the crude extract was tested against five gram-negative bacteria, namely Escherichia coli, Salmonella typhi, Pseudomonas aeruginosa, Aeromonas hydrophila, and Vibrio harveyi at a dose of 200 g/disk. Extract toxicity was tested on Artemia salina larvae at concentrations of 1,000, 500, 250, 125, 62.5, and 31.25 ㎍/mL. The results showed that the methanol and hexane extracts of H. durvillei had the highest activity against S. thypi and A. hydrophila, respectively, with inhibition zones of 26.2 mm and 21.0 mm. On the other hand, the two extracts did not show activity against E. coli and P. aeruginosa, respectively. The toxicity of the methanol extract of H. durvillei was twice as high as that of the hexane extract with half-maximal inhibitory concentration of 98.24 and 184.21 ㎍/mL, respectively. Thus, the methanol and hexane extracts of red seaweed H. durvillei have the potential as new antibacterial agents respectively against the pathogenic bacteria S. typhi and A. hydrophila, but also have the opportunity to be developed into antitumor herbal compounds.

• Membrane and Water Treatment
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• 제14권3호
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• pp.141-146
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• 2023

Algal organic matters (AOMs) are challenging to remove using traditional water treatment methods. Additionally, they are recognized as disinfection by product (DBP) precursors during the chlorination process. These compounds have the potential to seriously harm aquatic creatures. Despite the fact that AOMs and DBPs formed from algae can harm aquatic species by impairing their cognitive function and causing behavioral problems, only a few studies on the effects of AOMs and associated DBPs have been conducted. To assess the impact of extracellular organic materials (EOMs) produced by three different hazardous algal species and the chlorinated EOMs on zebrafish, this study used fish acute embryo toxicity (FET) and cognitive function tests. With rising EOM concentrations, the embryo's survival rate and mental capacity both declined. Of the three algal species, the embryo exposed to Microcystis aeruginosa EOM exhibited the lowest survival rate. On the other hand, the embryo exposed to EOMs following chlorination demonstrated a drop in CT values in both the survival rate and cognitive ability. These findings imply that EOMs and EOMs treated with chlorine may have detrimental effects on aquatic life. Therefore, an effective EOM management is needed in aquatic environment.

• Toxicological Research
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• 제28권2호
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• pp.129-137
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• 2012

Probabilistic ecological risk assessment (PERA) for deriving ecological protective concentration (EPC) was previously suggested in USA, Australia, New Zealand, Canada, and Netherland. This study suggested the EPC of cadmium (Cd) based on the PERA to be suitable to Korean aquatic ecosystem. First, we collected reliable ecotoxicity data from reliable data without restriction and reliable data with restrictions. Next, we sorted the ecotoxicity data based on the site-specific locations, exposure duration, and water hardness. To correct toxicity by the water hardness, EU's hardness corrected algorithm was used with slope factor 0.89 and a benchmark of water hardness 100. EPC was calculated according to statistical extrapolation method (SEM), statistical extrapolation $method_{Acute\;to\;chronic\;ratio}$ ($SEM_{ACR}$), and assessment factor method (AFM). As a result, aquatic toxicity data of Cd were collected from 43 acute toxicity data (4 Actinopterygill, 29 Branchiopoda, 1 Polychaeta, 2 Bryozoa, 6 Chlorophyceae, 1 Chanophyceae) and 40 chronic toxicity data (2 Actinopterygill, 23 Branchiopoda, 9 Chlorophyceae, 6 Macrophytes). Because toxicity data of Cd belongs to 4 classes in taxonomical classification, acute and chronic EPC (11.07 ${\mu}g/l$ and 0.034 ${\mu}g/l$, respectively) was calculated according to SEM technique. These values were included in the range of international EPCs. This study would be useful to establish the ecological standard for the protection of aquatic ecosystem in Korea.

• 한국수산과학회지
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• 제44권5호
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• pp.484-489
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• 2011

This study examined whether N-acetylcysteine (NAC), a glutathione precursor, could attenuate toxic effects of three fish anti-parasitic agents, trichlorfon, hydrogen peroxide ($H_2O_2$) and formalin, all of which are known to exert side effects through free radical production. Common carp Cyprinus carpio were fed with NAC (approx. 50 mg/kg/day) for 3 consecutive days prior to anti-parasite bathing for a 24 hr period. Mortality rates were examined during this 24 hr bathing period, and selected hematological and biochemical parameters were also assessed at the termination of anti-parasite exposure. The mortality rates and plasma glucose elevations caused by all three anti-parasitics were significantly reduced by NAC pretreatment. Trichlorfon, but not $H_2O_2$ or formalin, elevated plasma levels of aspartatetransaminase (AST) and alanine-transaminase (ALT), and these elevations were attenuated by NAC. There was no change in hematocrit values in any treatment. The results provide evidence for the attenuating effects of NAC against toxicity caused by anti-parasite agents that act through free radical-producing properties. The results found in this study also suggest that NAC may be administered to fish to minimize toxicity in fish parasiticide use.

• 한국동물생명공학회지
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• 제36권1호
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• pp.2-8
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• 2021

Dimethachlor is a synthetic herbicide, belonging to the chloroacetanilide group, that inhibits the undesirable growth of weeds via the suppression of very long-chain fatty acid synthesis. Although dimethachlor has been shown to run off from agricultural fields into aquatic ecosystems, the toxicity of dimethachlor on aquatic invertebrates and vertebrates is unknown. In our study, we assessed the toxicity of dimethachlor on developing zebrafish embryos by analyzing viability, hatching ability, and phenotypic changes. Embryonic viability decreased from 48 h post-fertilization (hpf) at the highest concentration of dimethachlor. Decreased hatching ratio, shortened body length, and pathological changes in the eye, heart, and yolk sac were observed at sub-lethal concentrations. Additionally, dimethachlor increased the number of apoptotic cells and level of reactive oxygen species 120 hpf. Our results indicate that dimethachlor may act as an anti-developmental toxicant when accumulated in an aquatic environment.

• 한국동물생명공학회지
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• 제37권3호
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• pp.162-168
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• 2022

Mecoprop-p, a chlorophenoxy herbicide, has been widely used since the 1980s. Due to its high water solubility, it could be detected in the aquatic environment, as it has already been detected in the surface water or groundwater in several countries. The toxicity of other chlorophenoxy herbicides has been reported; however, there are few studies on the toxicity of mecoprop-p, one of the chlorophenoxy herbicides, on aquatic organisms. Here, we investigated the toxic effects of mecoprop-p using zebrafish. After mecoprop-p exposure, we observed that the zebrafish larvae eyes did not form normally, heart edema was generated, and the body length was shortened. The number of cells undergoing apoptosis also increased in the anterior part including head, heart, and yolk sac of the mecoprop-p-treated zebrafish compared to the untreated controls. Moreover, cardiovascular structures, including the heart and aortic arches, were also malformed after exposure to mecoprop-p. Therefore, our results suggest that mecoprop-p could cause abnormal development in zebrafish larvae and there is also a high possibility that mecoprop-p would be toxic to other aquatic organisms.

• Environmental Analysis Health and Toxicology
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• 제19권1호
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• pp.65-72
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• 2004

Environmental risk assessment of cadmium compounds was conducted using national monitoring data of aquatic and terrestrial compartments of local area. Aquatic and terrestrial toxicities of cadmium compounds on algae, daphnid, fish, earthworm, springtails and other species were evaluated. The toxicity data evaluated in this study were mainly from ECOTOX database provided by US EPA. Assessment factors were determined according to the EU technical guidance document and/or OECD proposal. Predicted no effect concentration (PNEC) values of aquatic and terrestrial toxicity were 25$\mu\textrm{g}$/L and 0.2 mg/kg, respectively and they were compared with cadmium exposure data of several local areas, which were used as Predicted exposure concentration(PEC) values. Most of the local area were found to be not risky. However, the risk values (PEC/NEC) of some metropolitan areas were greater than 1 when the most conservative PNEC value was applied.

• 한국환경보건학회지
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• 제37권2호
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• pp.113-123
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• 2011

Objectives: Industrial development in Korea results in a rapid increase in the number of chemicals, some of which may be responsible for toxicity to aquatic ecosystems. In addition, the types of hazardous chemicals included in industrial effluents have gradually increased. Therefore, chemical analysis alone is not enough to assess ecological effects of toxic chemicals in wastewater. Methods: In response to new regulations as whole effluent toxicity (WET) tests for effluent discharge of 15 publicly owned treatment works (POTWs) and 25 industrial effluent treatment plants in Gyeonggi-do, which will be effective from 2011, a necessity of studies emerges that investigates toxicity levels. Results: In case of the public treatment plants, none of them had exceeded the criteria for ecotoxicity. As for individual wastewater discharge facilities, on the other hand, two types were found to exceed the criteria: pulp and paper manufacturing facilities and pharmaceutical manufacturing facilities. For the pulp and paper manufacturing facilities, monitoring results could not help determine the exact toxicant identification. However, Daphnia magna inhibition effect or death was found to leave white plums, suggesting that suspended solids treated and the polymer used in coagulant dose. In case of pharmaceutical manufacturing facilities, the general water quality parameters cannot affect Daphia magna. However, conductivity and salinity can have an effect to be 14,000 ${\mu}s/cm$, 8.1‰ by salts, respectively. Toxicity Identification Evaluation (TIE) and Toxicity Reduction Evaluation (TRE) procedures results appeared to be effective for identifying toxic compounds in $Cl^{-}$ and $SO_4^{2-}$. Conclusions: It is necessary to develop control measures for water treatment chemicals and salts used for processes such as coagulation in individual wastewater discharge facilities in order to achieve the goal to protect aquatic ecosystems in public waters.