Survival, Pb-uptake and behaviour of three species of earthworm in Pb treated soils determined using an OECD-style toxicity test and a soil avoidance test

Mature (clitellate) Eisenia andrei Bouché (ultra epigeic), Lumbricus rubellus Hoffmeister (epigeic), and Aporrectodea caliginosa (Savigny) (endogeic) earthworms were placed in soils treated with Pb(NO3)2 to have concentrations in the range 1000 to 10 000 mg Pb kg−1. After 28 days LC50−95%confidence limit+95%confidence limit values were E. andrei5824−361+898 mg Pb kg−1, L. rubellus2867−193+145 mg Pb kg−1 and A. caliginosa2747−304+239 mg Pb kg−1 and EC50s for weight change were E. andrei2841−68+150 mg Pb kg−1, L. rubellus1303−201+240 mg Pb kg−1 and A. caliginosa1208−206+212 mg Pb kg−1. At any given soil Pb concentration, Pb tissue concentrations after 28 days were the same for all three earthworm species. In a soil avoidance test there was no difference between the behaviour of the different species. The lower sensitivity to Pb exhibited by E. andrei is most likely due to physiological adaptations associated with the modes of life of the earthworms, and could have serious implications for the use of this earthworm as the species of choice in standard toxicological testing.