Snails in grapevine: active bioindication and drift effects of pesticides

More and more chemicals are produced in the world and a big part entry in the composition of pesticides. The intensive use of pesticides has ended up in chronic contamination of the ecosystem compartments: air, water and soil and their effects on the environment aren't much known. The snail is an appropriate model to bring data about effects of these contaminants because its particular place at interface soil-air-plant. Moreover it can be itself a source of contamination for their predators included humans. The aim of this study is to expose snails in real conditions of applications of pesticides and to measure the effects of drift on mortality. Snails were encaged in microcosms placed in a parcel of grapevine and in kerb (from 1m to the parcel). An area without contamination, ranged in 1.2 km, served as control. Five treatments (2 herbicides and 3 fungicides) occurred from May to July. The day of each treatment, soil deposition of pesticides was measured from 0 to 20 m, under wind, of the parcel. The results indicate no significant mortality due to pesticides in the parcel and in kerb. For the soil deposition of fungicides, average ranged from 0.308 to 106.6 g/ha in the parcel following the poised active ingredient and the poised treatment. These differences can be explained by meteorological conditions, height of vegetation and physic-chemical properties of the active ingredient among other things. For the herbicides, average concentrations ranged from 83.98 to 856.92 g/ha. The soil depositions (in percentage of applied doses) progressively decreased from 31.15 % to 0 % from 0 to 20 m of the parcel for the fungicides whereas for the herbicides, there is only deposition at 0 m reaching an average of 61.2 % for one of two formulations