To protect their vegetable crops from pests and diseases, growers in sub-Saharan Africa use generally high doses of chemicals on a weekly basis to avoid the risk of losing their production. In the absence of sanitary control quality of vegetables from the local market and the training of growers to use good agronomic practices especially chemical pesticides, all excessive use of chemical pesticides is possible and in fact regularly observed in the field. A study about the use of pesticides was carried out on 202 vegetable farms in the peri-urban area of Yamoussoukro, Côte d'Ivoire. Interviews gave information about pesticides applied by farmers. Risks of soil pollution and vegetable contamination were characterized by using biotest with the mosquito Aedes aegypti larvae as bio-indicator. The pesticides commonly used by farmers were lambda cyhalothrin + acetamiprid, indoxacarb + acetamiprid and lambda-cyhalothrin. Up to 14% of farmers used maneb as fungicide and 8% abamectin as miticide. Pesticide residues were found in 81% of vegetable samples and 88% of soil samples. More than 82% of farmers knew about the harmful effects of pesticides on human health. Vegetables were less contaminated when produced by farmers using alternatives to chemical pesticides such as plant extracts for crop protection. This easy-to-use bio-test could be a very smart tool to evaluate locally the risk of soil pollution and vegetable contamination by insecticide chemical residues.