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.

Recently, among the water treatment technologies, the forward osmosis (FO) system has been received much attention due to the advantages in energy consumption. However, the practical application of the FO system has been limited because of the remaining obstacles such as the absence of both adequate osmotic agent and efficient membrane. In this study, polymers having lower critical solution temperature (LCST) and upper critical solution temperature (UCST), one of the thermal responsive characteristics, are used as the osmotic agents. These materials could be recovered easily by heating them to above their LCST and to below their UCST, respectively. Finally, we believe that our results will provide insight into the synthesis of osmotic agents for water treatment applications.

대형녹조류인 Ulva pertusa는 전 세계 연안에 서식하는 저서성 종으로 대발생 또는 인공구조물에 착생되어 경제적, 사회적인 측면에서 문제를 야기시키고 있다. 착생생물을 제어하기 위해 신방오제인 ziram, diruon, zinc pyrithione (ZnPT), copper pyrithione(CuPT), DBNPA, triclosan 등이 방오도료로 사용 중이나, 대형 및 미세조류를 이용한 신방오 제들의 방오능 검증과 기초적인 연구자료가 부족한 실정이다. 따라서 본 연구에서는 초기 우점착생종인 구멍갈파래의 포자를 이용하여 방오제의 효능을 검증하고 생체막 형성의 우점종인 미세조류 Nitzschia pungens를 이용한 방오능을 검증하였다. 구멍갈파래포자의 운동성 검증에서 ziram과 ZnPT는 diuron, CuPT, DBNPA, triclosan보다 50% 높은 운동성 억제를 나타내었고 착생 검증에서는 ziram이 가장 낮은 착생률 1%로 나타났으며 CuPT는 100 ㎍/L의 농도에서 다른 대조군에 비해 80%의 성장율 억제를 보였다. 본 연구의 결과로 신방오제의 방오능을 검증하여 향후 방오능 검증에 기초자료가 될 것으로 사료된다.