TOXICITY TESTS OF TYPICAL MUTAGENIC PHENOLS ON DUNALIELLA SALINA

摘要

Algal tests are the predominant methods for studying aquatic ecotoxicology. Growth inhibition effects of three phenols and combined phenols at different concentration levels on unicellular green algae (Dunaliella salina) were tested according to the OECD guidelines for testing chemicals. Using 2,4-xylenol, paracresol, and phenol as the typical mutagenic toxicants, their concentrations were set according to the Chinese national drinking water health standard (GB5749-85). Four groups of tests were designed by combining any two of the three compounds; another group was the control. D. salina was cultivated in these groups, and the EC{sub}50 of each group was obtained. Based on the 48 h EC{sub}50 values, the microalgae showed increasing inhibition effects in the following order: 2,4-xylenol < paracresol < phenol The four groups of phenol combinations, for which the range of additive index of joint effect (AI) varied from 0.03 to 0.1, demonstrated that there were slight synergistic relationships among them.