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543224 
Journal Article 
Earthworm (Lumbricus terrestris) as indicator of heavy metals in soils 
Mahmoud, HM 
2007 
23-37 
The important role of earthworms in the biomagnification of heavy metals in terrestrial ecosystems and its role in the transfer of heavy metals toward higher trophic levels are widely recognized. In the present study the bioconcentration levels of essential (Cu, Fe, and Zn) and non-essential (Cd, and Pb) heavy metals were measured in soil and earthworm (Lumbricus terrestris) samples to evaluate soil contamination in different habitats and the validity of earthworm as a bioindicator of soil contamination and the selected ecosystems health status. Both soil and earthworms were sampled from Abu Rawash (about 8 km to the North of Giza Governorate) representing areas polluted by agricultural activities; Mostorod (about 10 Km to the North of Cairo) representing area moderately polluted by industry to examine whether earthworms populations originating from differently polluted terrestrial habitats differ in their tendency to accumulate heavy metals or not. For each of the metals, evidence suggests that bioconcentration depends on the metal concentrations in the soil; bioconcentration is greater at lower soil concentrations. Eearthworms' collected from industrial area exhibited different storage capacity and different concentration factors (concentration in animal/concentration in soil), effective bioaccumulation of some heavy metals by earthworm, revealed a strong influence from industrial pollution on the biotic community. This study for the first time presents data on the impact of heavy metal pollution on earthworms in Egypt. The positive correlation between some heavy metals concentration in the soil and in earthworms is noteworthy. In general the variation in heavy metals concentration in soil and earthworms in different sites may be significant depending on soil properties and pollution status. It will also be of interest for the future to analyze certain effects of metal concentration in soil on innate immune response of resident earthworms and to compare those with results from other geographical populations.