• Journal of the Korean Society of Marine Environment & Safety
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• v.18 no.2
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• pp.85-93
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• 2012

We study on the distribution characteristics of antifouling agents such as Sea-nine 211, Irgarol 1051, Diuron using HS-SPME method in southwestern coast of Korea. Short half-life of Sea-nine 211 was distributed in very low concentrations and/or below detection limits in all of the sampling points, both water and sediments samples. Irgarol 1051 was detected to have the highest concentration respectively $6.98{\mu}g/L$, 28.50 ng/g-dry wt in the seawater and sediments, and regional distribution characteristics did not appeared. Strong bioaccumulation and long half-life of Diuron was distributed higher concentration than in all sampling point and was analyzed to have the highest concentration(3882.22 ng/g-dry wt) Mo7(Mokpo)'s sediment. Irgarol 1051 and Diuron distributed in the shipbuilding industry and ship marina are located just at the point to found in high concentrations. In addition, the distribution of the antifouling agent materials were lower in concentration than in inner bay to outter bay in sediments. Antifouling agent materials from these results were contaminated high potential from port and shipbuilding industry located in inner bay.

• Korean Journal of Environmental Biology
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• v.38 no.2
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• pp.207-215
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• 2020

Toxic assessment of antifouling agents (diuron and irgarol) was conducted using the fertilization and the normal embryogenesis rates of the sea urchin, Mesocentrotus nudus. Bioassessment began with male and female reproductive cell induction. White or cream-colored male gametes(sperm) and yellow or orange-colored female gametes (eggs) were acquired and fully washed, separately. Then, the fertilization and normal embryogenesis rates were measured after 10 min and 48 h of exposure to the toxicants, respectively. The fertilization and embryo development rates were greater than 90% in the control, validating the suitability of both endpoints. The normal embryogenesis rates were significantly decreased with increasing concentrations of diuron and irgarol, but no changes in the fertilization rates were observed in concentrations ranging from 0 to 40 mg L^-1. The EC₅₀ values of diuron and irgarol for the normal embryogenesis rates were 20.07 mg L^-1 and 22.45 mg L^-1, respectively. The no observed effect concentrations (NOEC) were <1.25 mg L^-1 and the lowest observed effect concentrations (LOEC) were 1.25 mg L^-1 and 2.5 mg L^-1, respectively. From these results, concentrations of diuron and irgarol over 1.25 mg L^-1 and 2.5 mg L^-1, respectively, can be considered to have toxic effects on invertebrates, including M. nudus. The ecotoxicological bioassay in this study using the noted fertilization and normal embryogenesis rates of M. nudus can be used as baseline data for the continued establishment of environmental quality standards for the effects of antifouling agents(especially diuron and irgarol) in a marine environment.

• Membrane and Water Treatment
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• v.3 no.1
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• pp.35-49
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• 2012

In membrane processes, various agents are used to enhance, protect, and recover membrane performance. Applying these agents in membrane modification could potentially be considered as a simple method to improve membrane performance without additional process. Citric acid (CI) and sodium bisulfite (SB) are two chemicals that are widely used in membrane feed water pretreatment and cleaning processes. In this work, preadsorptions of CI and SB were developed as simple methods for polysulfone ultrafiltration membrane modification. It was found that hydrogen bonding and Van Der Waals attraction could be responsible for the adsorptions of CI and SB onto membranes, respectively. After modification with CI or SB, the membrane surfaces became more hydrophilic. Membrane permeability improved when modified by SB while decreased a little when modified by CI. The modified membranes had an increase in PEG and BSA rejections and better antifouling properties with higher flux recovery ratios during filtration of a complex pharmaceutical wastewater. Moreover, membrane chlorine tolerance was elevated after modification with either agent, as shown by the mechanical property measurements.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.5
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• pp.534-541
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• 2002

The use of triorganotins as insecticides, bacteriocides, and antifouling agents has increased dramatically over the past 30 years, In this paper, to evaluate the acute and chronic toxicity effects of various triorganotins (TBTO, TBTE, CTPT, TBTCI) on the growth of microalgae, Skeletonema costatum, we carried out the short term and long term experiments, respectively. In the short-term experiments, the growth of S. costatum was inhibited by the various triorganotins in the dose dependent manners, but recovered by the time laps. The growth inhibition of triorganotins were decreased in the groups with higher initial cell density. These data were resulted from the dilution effect and the biodegradation of triorganotins by the microalgae. In the long-term experiments, S. costatum died completely at the 1 $\mu$g/L of TBTP and CTPT, but didn't in short-term experiments. The facts suggest that the toxicity of the chronic exposure of triorganotins should be increased in the natural sea water with low phytoplankton density.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.31 no.3
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• pp.137-142
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• 2021

In this study, the development of the room temperature curable silica-based coating compositions for anticorrosive and antifouling performance in marine environments was carried out. The marine (plant) structures with many exposed parts are operated in harsh marine environments such as strong ultraviolet rays, extreme temperature differences and salt water corrosion. Organic paints that are easily degraded under these environments and easily eroded by physical stimuli such as waves can not play a role properly. Dense ceramic coatings on marine structures provide careful protections even in saltwater environments due to their high hardness and rust resistance. Therefore, in the case of ceramic coatings, their use and application range in marine structures can be greatly improved due to their functional advantages. In the present study, silica-based coating compositions based on colloidal silica with silane coupling agents, curing salts, and ceramic fillers were developed, and their applications as protective coatings for corrosion protection and fouling prevention in seawater were also studied.

• Environmental Analysis Health and Toxicology
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• v.15 no.4
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• pp.115-122
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• 2000

Biocides, or non-agricultural pesticides, are a broad class of chemical. They are including biological agents used to disinfect/sanitize, pesticides for non-agricultural use, wood preservatives, antifoulants, etc. Since the early 1980s, many adverse effects of biocides to human health and ecosystem have been found in the world. Especially, antifouling biocide like TBT caused serious toxic effects on the marine organisms. Therefore, OECD began to work on biocides in mid 1996 to help Member countries co-operate in the assessment and registration of these products. EU also announced the Biocidal Products Directive (BPD, 98/8/EC) in 1998 to harmonize regulatory approaches to allow EU countries to conduct evaluations of biocides more efficiently. Korea just start to consider of biocides regulation. Some biocides products are regulated, but not all the biocides which are using in Korea. Therefore, we need to make a appropriate regulation for the all biocides categories. In addition, there are necessary to develop risk assessment tools, to survey the use pattern and amount, to research on the ecosystem contamination by the biocides .

• Journal of Microbiology
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• v.39 no.4
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• pp.254-264
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• 2001

Sponges are host organisms for various symbiotic microorganisms such as archaea, bacteria, cyano-bacteria and microalgae. Sponges are also sources of a wide variety of useful natural products like cyto-toxins. antifouling agents, antibiotics, and anti-inflammatory and antiviral compounds, Symbiotic microorganisms is sponges can be sources of various natural products, because metabolites previously ascribed to sponges have recently been demonstrated to be biosynthesized by symbionts. If a symbiotic microorganisms from which some natural products are derived can be cultured, the microorganism could be used in a mass production of the bioactive comopounds. We summarize recent research on iso-lation and cultivation of sponge-symbiotic microorganisms and the symbiotic relationship.

• Journal of Food Hygiene and Safety
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• v.17 no.3
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• pp.137-145
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• 2002

Tributyltin compounds have been increasingly used in the form of plastic stabilizers, catalytic agents, industrial agricultural biocides, antifouling paint, and pesticides. Among these organotin compounds, large amounts of tributyltin(TBT) and triphenyltin(TPT) have been used as antifouling agents because they have a superior ability to prevent marine organism from being encrusted on ship bottoms and in culturing nets. Environmental pollution by these organotin compounds in the aquatic environment were undertaken. The international maritime Organization's established a provisional tolerable daily intake(TDI) of 1.6[micro]g TBTO/kg/ B.W. The Food and Agiculture Organization (of the United Nations)/world Health Organization's (FAO/WHO) proposed a TDI of 0.5ug TPT/kg BW/d. This study is conducted monitoring of TBT on seafoods in Korea and risk assessment for exposure on TBT in seafoods. Total hazard index(using Reference Dose : 0.3 ug TBTO/kg B.W/day) of intake exposure on seafoods is 0.04 as the 50th percentile, 0.08 as the 95th percentile. This value is estimated by Monte-Carlo simulation using Crystal Ball(Decisioneering Co., 2001).

• Proceedings of the Korean Society of Developmental Biology Conference
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• 2003.10a
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• pp.67-67
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• 2003

Tributyltin chloride (TBTCI) is an organotin compounds that have been widely used as antifouling agents and bioaccumulated in the food chain. TBTCI has been known to induce imposex in female gastropods. There are several reports that TBTCI increased testosterone level and inhibited the conversion of testosterone to estradiol by the aromatase cytochrome P450 enzyme. In this studies, we investigated the effects of TBTCI on steroidogenesis in testes, We dosed to 4-week-old Spragus-Dawleys (SD) male rats with TSTCI (0, 1, 5, 10, and 20mg/kg/day) daily by gavage for 14 days. TBTCI significantly decreased the weights of seminal vesicle, prostate, cowper's gland and LABC at 10 and 20mg/kg/day but significantly Increased the weights of liver at 10 and 20mg/kg/day and adrenals at 20mg/kg/day. mRNA levels of steroidogenic acute regulatory (StAR) and P450 aromatase were decreased and mRNA levels of cytochrome P450 17$\alpha$-hydroxylase/$C_{17-20}$ lyase (P450c17) were increased by TBTCI. TBTCI significantly increased serum testosterone level in dose-dependent manner. From above results, we found that TBTCI altered mRNA levels of enzymes related steroidogenesis, weights of organs and serum testosterone levels. This suggests that change of hormone levels may be due to alteration of mRNA levels of steroidogenic enzyme in testes, but further studies are necessary to investigate hormone levels in testis organ in order to find a relation of enzyme related to steroidogenesis with hormone levels. This work was supported by the Korea FDA Grant KFDA-03131-EDS-010.

• Korean Journal of Environmental Biology
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• v.38 no.4
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• pp.518-527
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• 2020

The aim of this study was to define the toxic effects of diuron and irgarol, which are new-antifouling agents, on the fertilization rate and normal embryogenesis rate in the sea urchin, Hemicentrotus pulcherrimus. In addition, the study was intended to confirm the hindrance of development in sea urchins. The fertilization rate of H. pulcherrimus was not decreased by the tested concentrations. However, the normal embryogenesis rate was decreased in a concentration-dependent manner. The 50% effective concentrations (EC₅₀) of normal embryogenesis rate were 7.12 mg L^-1 and 2.31 mg L^-1, respectively. As the embryos developed into pluteus larvae, after 18 h of exposure to diuron and irgarol at EC₅₀, development of the early gastrula stage was delayed, and significant developmental delays were observed after 24 h. After this, continuous developmental delays were observed in the process leading to the early gastrular, gastrular, early pluteus, and pluteus stages. Therefore, the toxic effects of diuron and irgarol on sea urchins were attributed to the delay in the developmental processes in the early life stages. Diuron and irgarol are highly persistent in the environment and have known-well toxic effects on various marine organisms including invertebrates, as shown in this study. Therefore, it is urgent to establish an environmental protection strategy to prevent the pollution of and preserve the marine environment.