To assess the hazards of chemicals for the soil, juveniles and adults of several soil organisms such as earthworms or snails have been used as biological models. To our knowledge, no terrestrial standardised bioassay concerns the effects of pollutants on the embryonic development of soil invertebrates even though this stage is a crucial part of an organism's life cycle. Moreover, embryos are generally more sensitive to pollutants than juveniles and adults. In this context, we aim to develop a bioassay allowing the assessment of the effects of chemicals on snail eggs, first focussing on some widely used pesticides. The chosen pesticides were commercial formulations of herbicides (Roundup®, Bypass®, and Basta®) and fungicides (Corail®, Valiant Flash®, Cabrio Top®, Bordeaux mixture and Thiovit®). Glyphosate, the active ingredient (a.i.) of two formulations (Roundup® and Bypass®), was also tested alone. Aqueous phase bioassay was performed to mimic exposure of eggs to the soil solution. For each product, hatching success was determined at the end of the embryonic development. For all contaminants, EC50 were lower than recommended concentrations for agricultural usage. The toxicity of glyphosate alone (EC50 = 1.3 g/l) was lower than those of commercial formulations (EC50 Bypass® = 0.09 g a.i./l and Roundup® = 0.018 g a.i./l), possibly in relation to the presence of surfactants in the commercial products. This work shows that snail embryos are a sensitive model to assess the hazard of pesticides for a non-target soil organism and constitutes a first step in the development of a new terrestrial embryotoxicity bioassay.