Toxicity assessment of low effect concentration (NOEC, LOEC, EC10 and NEC) to Pseudokirchneriella subcapitata

• Main Author: 王韻如
• Other Authors: Chung-Yuan Chen
• Format: Others
• Language: zh-TW
• Published: 2006
• Online Access: http://ndltd.ncl.edu.tw/handle/18290453455251575300

碩士 === 國立交通大學 === 環境工程系所 === 94 === This research is aimed to estimate the low effect concentrations of 108 chemicals on Pseudokirchneriella subcapitata (green algae) assessed by a closed system BOD bottle test. Toxicants including benzenes, alkanes, phenols, anilines, aldehydes, nitrile, alcohols, ketones, pesticides, and PAHs were obtained NOEC, LOEC, EC10 and NEC. Among these parameters, NOEC was found to be generally smaller than EC10 and were apparently lower than LOEC and NEC. For non-polar narcotics , polar narcotics and reactive toxicants, distinct linear relationship were identified between EC50 and low effect concentration. For non-polar narcotic chemicals, the Quantitative structure-activity relationships (QSAR) of four parameters were based on the octanol-water partition coefficient (Log P) was established with R2 and Q2 above 0.85. Further, for polar narcotic chemicals, the discriminating parameters including log P, ELUMO (Energy of the lowest unoccupied molecular orbital)were chosen to predict the toxicity effectively. These equations also show a good prediction. Finally, compared to literature data, results from this study show that the closed system BOD bottle test is greater sensitivity than conventional batch test and a good correlation was found in comparison with the fish (Fathead minnow). Hence, algal toxicity test can be considered as a surrogate test for estimating the toxicity of chemicals to Fathead minnow.