Effect of 1, 8-dihydroxyanthraquinone on body mass and protein content of earthworms

Liping HUANG; Jingwen CHEN; Yongming BAO; Xianliang QIAO; Xichuan YANG; Hongxiang CHEN

ABSTRACT

BACKGROUND:

Earthworms are one of the most important constituents in the ecosystem and become an environmental information carrier between terrestrial organisms and soil ecosystem. They were known as important non-target terrestrial soil organisms for assessing the general impact of pollution on the soil community. Protein content and growth rate in response to organic and heavy metal contaminants in soil are often used to assess the soil ecotoxicity.

OBJECTIVES:

To investigate the effects of 1, 8-dihydroxyanthraquinone,one representative of hydroxyanthraquinones, on the earthworm eisenia foetide under laboratory conditions of the growth rate and protein content.

DESIGN:

Experimental study based on the experimental animals.

SETTING:

Eco-toxicological laboratory and genetic laboratory in a university.MATERIALS The experiment was conducted in the Eco-toxicological Laboratory and the Genetic Laboratory, Dalian University of Technology from February to July 2004. Eisenia foetide, a kind of international standard earthworm, were maintained in a soil mixture before experiments. Earthworms used in this study were healthy adults with 1 -2 month old and 200 - 300 mg mass and the number of the earthworms in each analytical experiment was 10.

METHODS:

The earthworms were removed from the soil 12 hours before use and stored in Petri dishes on damp filter paper to void gut contents.Then, these earthworms were exposed for various durations to soils contaminated. The earthworm weight and protein content were determined respectively at every 7 days interval.MAIN OUTCOME

MEASURES:

Effects of 1, 8-dihydroxyanthraquinone on growth rate and protein content of earthworms.

RESULTS:

No lethal effect of 1, 8-dihydroxyanthraquinone was observed even at the highest concentration(1.0 g/kg soil) of exposure. The sub-lethal effect, however, was evident at all the concentration scale. 1,8-dihydroxyanthraquinone caused a significant reduction in the growth rate (maximum -22. 5% ) at the dosage of 1.0 g/kg and 28 days contact time.Additionally a reduction in total soluble protein was observed in all treated worms(maximum- 39.6% ) at the dosage of 0. 8 g/kg and 7 days contact time.

CONCLUSION:

1, 8-dihydroxyanthraquinone was potentially dangerous to the soil ecosystem and more ecological risk assessment of this chemical material should be thoroughly carried out.