넙치(Paralichthys olivaceus) 수정란의 부화율에 대한 중금속(Cd, Cu, Zn)의 급성독성을 조사하였다. Cd, Cu 및 Zn (0, 10, 100, 500, 1000, 2500, 5000 ppb)에 수정란을 48h 노출시킨 후, 정상 부화율을 백분율로 나타내었다. Cd, Cu 및 Zn을 포함하지 않는 대조구에서는 정상 부화율이 80% 이상을 나타냈으나, 중금속 농도가 증가할수록 정상 부화율은 급격히 감소하였다. 정상 부화율은 Cd, Cu 및 Zn에 대해 농도 의존적으로 감소하였으며, 각각 1000, 100, 100 ppb 이상의 농도에서 유의적이 차이를 나타내었다. P. olivaceus의 정상 부화율에 대한 Cd, Cu 및 Zn의 반수영향농도(EC50)를 이용한 독성은 Zn¤Cu¤Cd 순으로 강한 것으로 나타났으며, 이들 중금속에 대한 EC50는 각각 584, 1015, 1282 ppb를 나타내었다. Cd에 대한 NOEC는 500 ppb를 나타냈고 LOEC는 500 ppb를 나타내었다. Cu와 Zn의 NOEC와 LOEC 각각 100 ppb와 500 ppb로 유사한 값을 나타내었다. NOEC와 LOEC 결과로부터 자연생태계 내에서 Cu와 Zn 농도는 100 ppb, Cd 농도는 500 ppb를 초과할 경우 P. olivaceus 수정란의 정상 부화율은 감소할 것으로 판단된다. 본 연구결과를 바탕으로, P. olivaceus의 정상 부화율을 이용한 생물학적 시험은 중금속과 같은 유해물질에 대한 해양생태계의 영향을 판단하기 위한 시험방법으로 유용하게 이용될 수 있을 것으로 판단된다.

This study investigated both leaching of heavy metals and ecological toxicity when coal bottom ash (CBA) generated by power plants has been used to reduce both erosion and turbidity of surface runoff at construction sites. The Korean leaching test (KLT) method, sequential extraction method, and acute toxicity test using Daphnia magna were performed to evaluate the environmental impacts and the ecological risks of CBA. According to the results of the KLT method of CBA, trace amounts of Cu were leached at limit of quantitation whereas metal leaching was not monitored for other heavy metals. Through the sequential extraction method of CBA, the relatively high leaching potential was found for As and Pb due to greater fraction of exchangeable (F1) and bound to carbonates (F2), and reasonable probability of leaching under the reducing/anaerobic environment was expected for Cu due to high faction of bound to Fe?Mn oxides (F3). However, significantly low probability of leaching was expected for Cd, Cr, Ni, and Zn with grater fractions of bound to organic matter (F4) and residual (F5). Additionally, total amount of heavy metals in CBA was lower than criteria for soil pollution concerns, and were similar or slightly lower levels than the ‘15 National soil average concentration excluding Cr6+. Finally, acute toxicity test using Daphnia magna display no impact for mobilization and lethality in either the prefiltration or post-filtration experiment, indicating that the ecological toxicity was insignificant with zero values of toxic unit. Consequently, no environmental impacts or ecological toxicity are expected when CBA generated by power plants has been used to reduce both erosion and turbidity of surface runoff at construction sites.

This experiment was carried out to investigate the effects of heavy metals (cadmium, chromium, copper and lead) on the seed germination of Arabidopsis thaliana, and examinated the removal effects of biostone and green tea on the heavy metal toxicity. Cadmium and chromium among the four heavy metals had no effect on the seed germination even in the concentration fifty times higher than in the official standard concentration of pollutant exhaust notified by the Ministry of Environment. However, seeds were not germinated in the concentration of copper ten times higher and in the concentration of lead fifty times higher than the official standard concentration. When seeds were sown in the solutions of lead (15, 20, 25 and 30 mg/L) and copper (15 and 20 mg/L), the seed germination rates were 0% and less than 10%, respectively. However, when biostone (3 g/30 ml) was added, the seed germination rate was 100% in all the concentrations. The germination rate was 100% in distilled water and copper solution (5 mg/L). However, green tea (0.2 g/30 ml) was added, the seed germination rate was 0% in both. The results show that cadmiun and chromium had no effect on the seed germination, but lead and copper decreased the rate of seed germination of Arabidopsis thaliana. Biostone removed heavy metal toxicity, but green tea did not removed heavy metal toxicity during germination.