US EPA

4160312 

Journal Article 

The use of biomarkers in Daphnia magna toxicity testing. IV. Cellular Energy Allocation: A new methodology to assess the energy budget of toxicant-stressed Daphnia population 

De Coen, WM; Janssen, CR 

1997 

Yes 

Journal of Aquatic Ecosystem Stress and Recovery
ISSN: 1386-1980 

BIOSIS/98/10781 

6 

1 

43-55 

English 

BIOSIS COPYRIGHT: BIOL ABS. The Cellular Energy Allocation (CEA) methodology was developed as biomarker technique to assess the effect of toxic stress on the energy budget of test organisms. This short-term assay is based on the biochemical assessment of changes in the energy reserves (total carbohydrate, protein and lipid content) and the energy consumption (electron transport activity). The CEA methodology was evaluated using Daphnia magna juveniles exposed for 96 h to sublethal lindane and mercury chloride concentrations. The ecological relevance of the CEA assay was assessed by comparing the sub-organismal response with population level parameters (obtained from 21 day life table experiments) such as the intrinsic rate of natural increase (rm) and the mean total offspring per female. Two different methodologies were used to assess the effect levels: the no (lowest) observed effect level (NOAECs-LOAECs) approach and the regression-based approach. Both toxicants caused a significant decrease in