원유의 WSF가 넙치의 수정란 및 자어발생에 미치는 독성영향을 알아보기 위하여 유류의 농도에 따른 부화소요시간, 부화율, 생존율, 호흡, 심장박동수의 변화 및 기형율 등을 조사하였다. 부화소요시간은 대조구와 실험농도구간에 유의한 차이를 보이지 않았다 (p>0.05). 부화율은 대조구와 1.9 ${mu}g/mL$ WSF에서 80% 이상이었으나, 3.9 ${mu}g/mL$ WSF 이상에서는 55.7% 이하로 나타나 유의한 차이를 보였다(p<0.05). 한편 부화 후 3일 동안의 생존율은 농도의존적 감소현상을 나타내었다. 산소소비율은 대조구에 비해 낮게 나타났으며, 심장박동수는 대조구의 경우 부화 전에 비해 부화한 후 다소 증가하였으나, WSF 노출구에서는 감소하는 현상을 나타내었다. 기형율은 WSF 농도증가에 따라 증가하였으며, 주로 척추만곡과 척추형성부전의 현상을 보였다
This study was carried out to investigate the toxic effect of WSF (water soluble fraction) in crude oil on the hatch, survival rate, abnormality and physiological activity of fertilized eggs and early larvae in Paralicthys olivaceus. The time required in hatching the fertilized eggs exposure to crude oil was 50.8${sim}$53.2 hours both in control group and experimental group, showing no significant difference(p>0.05). The hatching rate in the control group was more than 80% in 1.9 ${mu}g/mL$ WSF concentration, but hatching rate was less than 55.7% in below of 3.9 ${mu}g/mL$ WSF concentration, showing significant difference (p<0.05). The survival rate on the 3rd day of early larval stage was 61.96% with 1.9 ${mu}g/mL$ WSF, 11.1% with 3.9 ${mu}g/mL$ WSF, and they all died with other concentration levels. The oxygen consumption rate in experimental groups was lower than control group. The heart rate (no./min) was 47.4${sim}$52.8 before hatching and there was no significant difference between control group and experimental group, but heart rate reduced with the decrease of WSF concentration after hatching. The abnormality was 1.1% in the control group whereas 36.7% with 3.9${mu}g/mL$ WSF, and abnormality was mostly comprised of incomplete spinal formation and spinal curvature. The results of this study suggest that even low concentration to WSF affects the early development of the flounder, Paralicthys olivaceus.
