How terrestrial snails can be used in risk assessment of soils.
Among soil invertebrates, terrestrial snails are herbivorous and detritivorous organisms exposed to polluted soils by both digestive and cutaneous routes. Using laboratory-reared snails (Helix aspersa aspersa), we describe how the effects of contaminants on survival and growth of snails can be evaluated in laboratory bioassays. A national ring test was performed to assess the effect of Cd added to the soil or to the food. The ecotoxicity of sewage sludge also was evaluated. The present results demonstrate that toxicity depends on both the pollutants and the exposure route. Cadmium was sixfold more toxic for snails exposed via food contamination (median effective concentration [EC50], 68-139 microg/g) than via soil contamination (EC50, 534-877 microg/g), whereas the opposite occurred with the sewage sludge (EC50, 55% of sludge in the food and 10% of waste in the soil). A logistic relationship linked growth inhibition and internal Cd concentrations, which can reach 2,000 microg/g in the viscera of snails exposed to 626 microg/g in the food. No clear trend was found between Cu, Zn, Pb, Cr, and Ni concentrations in the sludge and in snail tissues. These data enabled the development of an international standard, which should enhance the use of terrestrial gastropods for both fundamental research and routine risk assessment in the terrestrial environment.
Department of Environmental Biology, EA 3184 Unité Sous Contrat-Institut National de la Recherche Agronomique, University of Franche-Comté, Place Leclerc, 25030 Besançon cedex, France. annette.devaufleury@univ-fcomte.fr
Annette
A
de Vaufleury
Michaël
M
Coeurdassier
Pascal
P
Pandard
Renaud
R
Scheifler
Christiane
C
Lovy
Nadia
N
Crini
Pierre-Marie
PM
Badot
D000818:Animals; D001681:Biological Assay; D001682:Biological Availability; D002104:Cadmium / Q000032:analysis*; D004305:Dose-Response Relationship, Drug; D017753:Ecosystem; D004784:Environmental Monitoring / Q000379:methods*; D008670:Metals; D019216:Metals, Heavy / Q000032:analysis; D018570:Risk Assessment; D012722:Sewage; D012908:Snails; D012987:Soil; D012989:Soil Pollutants / Q000032:analysis*; D018675:Toxicity Tests
D008670:Metals; D019216:Metals, Heavy; D012722:Sewage; D012987:Soil; D012989:Soil Pollutants; D002104:Cadmium