선박운항의 효율성을 감소시키는 생물부착(biofouling)을 방지하기 위해 사용되는 방오시스템(antifouling system)은 연안의 선체 수리, 해상 부착생물 제거 및 재 페인팅과정에서 해양으로 유출될 수 있다. 이에 대한 법적규제는 마련되어 있지 않아, 해양 생태계에 부정적인 영향을 초래할 할 수 있을 것으로 우려되고 있다. 선체청소배출수에 포함된 오염화학 물질과 관련된 잠재적인 독성 위험이 우려됨에도 불구하고, 이에 대한 생물의 독성영향을 보고한 사례는 매우 제한적이다. 본 연구에서는 선체청소배출수에 노출된 넙치 수정란에 대한 발생독성영향을 분석하였다. 현장에서 실제 선체를 청소한 배출수를 채집하여 원수(wastewater)와 페인트 입자를 제거한 여과한 폐수(0.45 μm Lab filter wastewater)로 나누어, 희석 배율(10배, 100배, 1000배)에 따른 치사 및 아치사 수준의 생태독성영향을 평가하였다. 선체청소배출수의 화학조성은 결과, 구리(Cu), 철(Fe), 아연(Zn)이 높은 농도로 확인되었다. 선체청소배출수에 노출된 모든 실험구의 사망률은 유의한 차이가 없었으나, 심장 부종, 척추만곡, 꼬리지느러미 기형, 발달 지연의 아치사 수준의 형태발생기형 영향이 나타난 것을 확인할 수 있었다. 노출 6시간 후 전사체분석을 통해 독성기작을 분석한 결과, 선체청소배출수에 노출된 넙치 배아에서는 Nervous system development, Cell development, Muscle development, Animal organ development pathway와 관련된 유전자들이 유의하게 차등 발현되었다. 본 연구 결과는 선체청소배출수가 연안에 서식하는 넙치의 발생에 미치는 급성독성영향을 규명하여, 연안 해양환경을 보호하기위한 선체청소배출수의 관리기준 마련에 유용한 정보로 활용될 수 있을 것으로 생각된다.

Over the past decade, there has been global expansion in the advancement of underwater cleaning technology for ship hulls. This methodology ensures both diver safety and operational efficiency. However, recent attention has been drawn to the harmful effects of ship hull-cleaning wastewater on marine animals. It is anticipated that this wastewater may have various impacts on a wide range of organisms, potentially leading to populationand ecosystem-relevant alterations. This concern is especially significant when the wastewater affects functionally important species, such as aquaculture animals and habitat-forming species living in coastal regions, where underwater cleaning platforms are commonly established. Despite this, information on the ecotoxicological effects of this wastewater remains limited. In this mini review, we discuss the adverse effects of wastewater from in-water cleaning processes, as well as the current challenges and limitations in regulating and mitigating its potential toxicity. Overall, recent findings underscore the detrimental effects posed by sublethal levels of wastewater to the health status of aquatic animals under both acute and chronic exposure.

미세플라스틱 입자는 환경 내 어디에나 존재하며 크기, 모양 또는 유형의 표준화된 입자가 아 니다. 따라서 독성자료를 바탕으로 해수, 퇴적물 등 해양환경의 다차원을 정확하게 평가하고 관리하는 위험평가 프레임워크를 구축하는 것은 매우 어렵다. 본 연구에서는 해양환경 미세플 라스틱의 특징과 영향을 조사하였고, 해양환경 미세플라스틱의 분포와 생물영향에 따른 위해 도 평가 프레임워크(초안)를 제안하고 있다. 환경 미세플라스틱의 특성은 매우 다양하지만 대 부분의 독성 데이터는 독특한 형태와 유형에 집중되어 있으며, 실험실 노출 생물과 관리해야 하는 생물 종도 다르다. 실제적으로, 지금까지의 수집된 연구결과는 위해성평가에 활용하기에 독성 데이터 품질에 있어 불확실성이 높기도 하며, 전통적인 위해성평가 프레임워크를 적용 하는 데 있어 고려할 부분이 많이 존재한다. 그러나, 현재 미세플라스틱 관리에 대한 국제사회 의 움직임이 점차 강화되고 있고, 해양환경의 미세플라스틱 오염도가 높아지고 있는 점을 고 려하면, 해양환경의 미세 플라스틱 특성에 기초한 위해성평가 기법 구축에 대한 추가 연구가 제안되어야 할 것이다.

Larvae from the marine medaka fish Oryzias javanicus were exposed with polystyrene microplastics (MPs) for 24 h. Exposure to waterborne fluorescent MPs showed clear ingestion and egestion in feces. Under constant MPs, the concentration of dissolved oxygen significantly decreased in 24 h compared to the control. Significant intracellular reactive oxygen species and malondialdehyde contents were detected in larvae, indicating oxidative stress and lipid peroxidation. Significant elevations in mRNA expressions of heat shock protein 70 and antioxidant defense system genes (glutathione reductase, glutathione peroxidase, catalase, and superoxide dismutase) were measured with increases in enzymatic activity of oxidative stress-related proteins. Taken together, the alterations to the molecular and biochemical components suggested that waterborne MPs had an oxidative stress effect on marine medaka larvae.

The inflammatory response to infections, such as bacteria and viruses is mediated by multiple host factors. The tumor related-genes are the important cytokines in mammals. However, a number of tumor related-genes are not identified in the rock bream. Here, we have reported the identification and molecular characterization of the tumor related genes. The LPS-induced TNF-α factor 1 and 2 (LITAF1, LITAF2), tumor necrosis factor superfamily member 14 (TNFSF14), tumor necrosis factor receptor superfamily member 14 (TNFRSF14) and translationally controlled tumor protein (TCTP), programmed cell death 10 (PCD10) from rock bream are used for the under investigations. The LITAF1 and LITAF2 consist of 138 and 163 amino acids with a conserved LITAF domain. TNFSF14 and TNFRSF14 comprise 266 and 181 amino acid, respectively. TCTP encompasses of 170 amino acid containing two conserved TCTP signatures. Furthermore PCD10 consists of 210 amino acids. Using quantitative real-time PCR, we have obtained expression analysis results of LITAF1 and 2, TNFSF14, TNFRSF14, TCTP, PCD10 in the various tissue. Compared to the control, the tumor related genes mRNA is detected at a high levels in gill (LITAF1, TCTP), intestine (LITAF2), liver (PCD10), spleen (TNFSF14) and RBC (TNFRSF14). We have also performed gene expression analysis in the kidney, spleen, liver and gill after challenging with Streptococcus iniae, Edwardsiella tarda and Red seabream iridovirus. We have acquired the dynamic regulated mRNA expression to each of pathogen according to the tissue. Expression of tumor related-genes mRNA are significantly increased by infected with pathogens in most of the tissue. But oddly, PCD10 mRNA is expressed significantly decreased by S. iniae infection in all of tissues. Our results reveal that rock bream tumor relatived-genes may be involved in rock bream immune responses to pathogen infections, as well as, they also act like potential biomarkers for innate immunity.

Translationally controlled tumor protein (TCTP) is one of important immune regulator. TCTP has been implicated in cellular processes including the cell growth, cell cycle progression, apoptosis regulation and the protection of cells against various stress condition. In this study, we cloned and characterized TCTP from rock bream (Oplegnathus fasciatus), which is an economically important species in the Korea aquaculture industry. The Full-length of rock bream TCTP (RbTCTP) cDNA was 1041 bp and contained an open reading frame (ORF) of 513 bp, which encoded 170 amino acid sequence. The 5' untranslated region (UTR) was 90 bp while the 3' UTR was 538 bp, containing a polyadenylation signal (ATTAAA). The identity of amino acid sequence was 76%, 75% and 74% in tilapia, orange-spotted grouper and Japanese seaperch, respectively. The positions of microtuble-binding region, Ca⁺ binding region and TCTP signature regions in RbTCTP were similar with those of other fish species and mammalian. The RbTCTP mRNA was expressed highest in the muscle. Expression of TCTP mRNA were significantly variable according to injection of red seabream iridovirus (RSIV), Streptococcosis (S. iniae) and Edwardsiella tarda (E. tarda).

Spilled oil into marine environments are known to induce disturbance not only hepatodetoxification system but also immune function in fish. However, toxic mechanisms on immune system and complex toxicity of crude oil have not been fully investigated. Innate immune response considered on the attractive effect-based monitoring tools due to their capacities to predict population disturbances by modification of disease susceptibility. In the study, to clarify the toxic effects of Hebei sprit spilled crude oil on fish immune system, multiple hepatodetoxific enzymes (Cytochrome P4501A and GST) and cytokines such as Interleukin-1beta (IL-1β), granulocyte colony-stimulating factor (G-CSF) were evaluated in juvenile Rockfish fed individually the gelatin-capsulated Iranian Heavy Crude Oil (IHCO). At 12 h after treatment, the oil-fed groups were shown higher concentrations of biliary 1-OH pyrene fluorescence metabolite and CYP1A expression than the control group. Cat. L and G-CSF mRNA also increased significantly at initial stage of exposure (from 12 h to 48 h after exposure) but decreased to the level of control group or less. 72 h post-oil injection, fish were intraperitoneallyadministered an LD50 dose of Streptococcus iniae (FP.5228; Korea Fish Diseases Information Center). Host survival was monitored for 7 days and cumulative mortality rate was calculated. Host mortality rate was increased significantly in oil exposure group compared to sham group.