Context
Plant protection products are essential nowadays for controlling crop pests. Their properly managed use contributes to producing food that is healthy, good quality and affordable for the consumer. However, using a plant protection product can result in active substance or metabolite residues occurring in the plant products.
Maximum residue levels (MRLs) of pesticides are fixed at national, European and international level for the various active substances on the different crops for which they are authorised. The aim is to protect the consumer, to check that pesticides are used correctly and to promote international trade in food. The MRL may be defined as the maximum pesticide concentration permitted in a food at the time of marketing. It is the result of using the plant protection product in accordance with good agricultural practice and it guarantees that there will be no effects on human health. Working out an MRL for a plant product is a three-stage procedure which involves establishing the critical good agricultural practice, residue analysis on the basis of field and laboratory experiments under controlled conditions and finally, risk assessment. Directive 91/414/EEC (regulating the placing of plant protection products on the market within the EU) lays down the conditions for carrying out residue trials.
Objectives
The aim of the project is to carry out residue trials under controlled conditions (in the field and at the laboratory) in order to supply the scientific data required for plant protection product registration and, in particular, establishing the maximum residue levels (MRLs) of pesticides. This work is carried out in accordance with European (Directive 91/414/EEC) and international regulations (CODEX/FAO/WHO recommendations) on pesticide residues and according to the OECD principles of Good Laboratory Practice (GLP C04 certificate).
Results obtained
Each year the Plant Protection Products and Biocides Physico-Chemistry and Residues Unit in foodconducts a hundred or so residue trials for different insecticides, acaricides, fungicides, herbicides and growth regulators on a variety of fruit, market garden and cereal crops.
Residue trials comprise a field part (setting up plots in the field or under cover, treatment in accordance with good agricultural practice, sampling, sending the samples to the laboratory and a field report) and an analytical part (delivery, preparation and storage of the samples at the laboratory, development, optimisation and validation of the analytical method, determining pesticide residues in the samples, verifying method effectiveness during sample analysis and a final report). Our laboratory is also responsible for drawing up study plans, carrying out Quality Assurance inspections and storing the raw data in accordance with GLP. The Unit’s special combination of the agronomic and chemical aspects of pesticide research enables complete residue trials to be carried out, from trial set-up in the field through to sample analysis. The analytical methods developed and validated by our chemists are used to analyse the samples collected in the field by our agricultural scientists. The laboratory also carries out stability studies of residues in storage as well as processing studies.
Trials are also undertaken in cooperation with other European institutions in Belgium, France, Germany, the United Kingdom, the Netherlands, Italy, Spain, Greece, Hungary and also in Africa (Ivory Coast). The Unit has thus come to specialise in the management (as study director) of multi-site residue trials where the field part and the laboratory part are carried out at two different institutions under the OECD Directive on the management of multi-site studies in accordance with GLP.
Studies are carried out on field crops (large-scale crops) and also on small-scale (minor) crops. Although economically of less interest to the agrochemical industry, the latter are nevertheless important to growers and consumers. The (open) list that follows gives an idea of the crops on which the Unit has carried out residue trials: citrus fruits (oranges, clementines), pome fruits (apples, pears), stone fruits (plums, cherries), tropical fruits (bananas, pineapples, kiwis), berries and small fruits (grapes, strawberries, raspberries, gooseberries, blackcurrants, blueberries), fruiting vegetables (tomatoes, cucumbers, gherkins, melons, peppers), root vegetables (carrots, celeriac, turnips, salsify, radishes), bulb vegetables (onions) stem vegetables (leeks, celery), leafy vegetables (lettuces, endives, lamb’s lettuce, spinach, witloof), brassica (round cabbage, cauliflowers, broccoli, curly kale, Brussels sprouts), aromatic herbs (parsley, chives), legumes (beans, peas), mushrooms, potatoes, cereals (wheat, six-rowed winter barley, maize, rape, sunflower, linseed) and industrial crops (sugar beet, chicory).
Contribution
The Plant Protection Products and Biocides Physico-Chemistry and Residues Unit carries out all of the steps in a residue trial (field work and analysis) or alternatively manages, as study director, a multi-site residue study in partnership with other institutions in Europe. The Unit submits a full report to the client for the purposes of plant protection product registration.
Partners
Pesticide manufacturers, including prominent multinationals as well as local or international generic manufacturers.
- Federal Public Service Public Health, Food Chain Safety and the Environment
- Regional Plant Protection Products Committee
- COLEACP (Europe, Africa, Caribbean, Pacific Liaison Committee).
- Residue trial providers in Belgium (BEAGx-CA-LP, LISEC, Redebel), France (Promo-Vert), Germany (GAB Biotechnologie GmbH), the United Kingdom (Agrisearch UK Ltd, OAT Ltd), the Netherlands (Agro Research International), Italy (SPF GAB Italia, Agroblu, ARA), Spain (recerca agricola / SynTech Research), Greece (Agrolab, Agroblu, Hellafarm), Hungary (PPSCS), the Ivory Coast (CUECDA), etc.
Funding
- SPF Public Health