Managing strategies for organochlorine contaminated soils for a safe food production

Summary

Background:
Organochlorine pesticides such as dieldrin, DDT and others are highly persistant pesticides, which were applied world wide against pests in horticulture, fruit and arable crops. Although they are forbidden since more than thirty years in the European Union (EU), the compounds remain still in soil. Several crops are known to accumulate these pesticides in eatable parts up to critical levels. For instance dieldrin is detected in high economic value crops such as cucumbers (Cucurbitaceae) and in tomatoes (Solanaceae). Besides plant type and climatic conditions, soil properties, e.g. pH and soil organic carbon content influence the pesticide uptake. In particular in labelled food and feed stuff production, such as organic farming according to EU Regulation (EEC) No. 2092/91, consumer expectations in safe, high quality food are extremely high. Since organic farming is prospering – more than 10% of vegetable production is certified organic in Switzerland – the organochlorine residues in organic food stuff have become a major issue for food control authorities. Enquires showed that imported food from EU countries was partly highly contaminated with organochlorine pesticides such as pumpkin seed and oil. Hence, the organochlorine problem in food stuff is expected to occur EU wide.