Application of Hydrophobicity Parameters to Prediction of the Acute Aquatic Toxicity of Commercial Surfactant Mixtures
作者:
D.W. Roberts,
S.J. Marshall,
期刊:
SAR and QSAR in Environmental Research
(Taylor Available online 1995)
卷期:
Volume 4,
issue 2-3
页码: 167-176
ISSN:1062-936X
年代: 1995
DOI:10.1080/10629369508029914
出版商: Taylor & Francis Group
关键词: acute toxicity;Daphnia magna;hydrophobicity;narcosis;mixture;nonionic surfactant
数据来源: Taylor
摘要:
Ethoxylated alcohols are the most extensively used nonionic surfactants in detergent products. The application of QSAR to their aquatic toxicity is complicated by the fact that they are multicomponent mixtures, the parent alcohols being often mixtures of isomers and homologues, each one being ethoxylated to varying degrees. A spreadsheet method for calculation of aquatic toxicity of such nonionic surfactant mixtures is presented. The method is based on a combination of the Könemann narcosis QSAR and mixture toxicity equations based on the principle of concentration addition. Log P values used in the spreadsheet calculations are themselves calculated by spreadsheet formulae based on the Leo and Hansch method modified by incorporation of the position dependent branching factor originally applied to linear alkylbenzene sulphonates. Close agreement between calculated and experimental EC50 values (48 hrDaphniatests) is obtained for a range of ethoxylated alcohols having a diversity of branching patterns, carbon numbers and degrees of ethoxylation. The effects of increasing carbon number (decreasing EC50), branching (increasing EC50) and increasing degree of ethoxylation (increasing EC50) are all quantified.
点击下载:
PDF (521KB)
返 回