This PhD thesis describes the risks behind the intensive use of plastic mulch and pesticides in agriculture. We went through the example of intensive vegetable production in Southeast Spain. We assessed the plastic and pesticide residues in soils and their effects on the soil microbiome in three conventional and three organic farms. We found that plastic and pesticides residues were present in all conventional fields. So we investigated the potential pesticides sorption on plastic in laboratory conditions. We also investigated the plastic debris impacts on the soil physicochemical properties. We extended the field assessment by measuring the plastic residues in the faeces of sheep grazing on the plastic contaminated agricultural soils. Finally, we tested the combined effect of plastic and pesticides residues present in soil on the lettuce production. We concluded by reflecting on the possible action to control the plastic and pesticides residues contamination.