Toxicity of chemicals to microalgae in river and in standard waters.
Environ Toxicol Chem
; 22(6): 1368-79, 2003 Jun.
Article
in En
| MEDLINE
| ID: mdl-12785596
ABSTRACT
The influence of the composition of natural waters on the toxicity of chemicals to microalgae was studied on samples representative of western European rivers. Effects of zinc, pentachlorophenol (PCP), 4-nonylphenol (4-NP), phosalone, and 2,4,5-trichloroaniline (TCA) on algal growth were tested in river waters without adding any nutrients or cosolvents, and in the International Standards Organization (ISO) medium for comparison. The mean values of effective concentrations reducing the algal growth by 50% (EC50s) after 72 h based on measured concentrations did not differ significantly in natural waters and in standard medium for 4-NP (0.5 mg/L) and phosalone (0.8-0.9 mg/L). These values were two or three times higher in rivers than in ISO medium for PCP (0.25 vs 0.1 mg/L), TCA (1.69 vs 0.73 mg/L), and zinc (0.20 vs 0.056 mg/L). Although the mean values were of the same order of magnitude, the distribution of the EC50 values ranged over 1.5 and 2 log concentrations in surface waters. Therefore, in view of a refined hazard assessment of a chemical on a local scale, it would be advisable to use the actual river water of the concerned aquatic environment in testing. Correlations between toxicity data and the physicochemical characteristics of the waters identified classic parameters such as water hardness or conductivity as factors that significantly influenced the toxicity of the ionizable compounds PCP and zinc. On the other hand, organic materials or suspended solids, but only at high levels, affected the toxicity of 4-NP, an organic chemical with high adsorption potential. No correlation could be drawn for phosalone and TCA.
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Collection:
01-internacional
Database:
MEDLINE
Main subject:
Water Pollutants, Chemical
/
Water Supply
/
Eukaryota
/
Fresh Water
Type of study:
Prognostic_studies
Language:
En
Journal:
Environ Toxicol Chem
Year:
2003
Document type:
Article
Affiliation country:
France