Dr. André de Kok

and detection systems. The pesticide laboratory in Amsterdam has been assigned as National
Reference Laboratory for pesticide residues, in The Netherlands.
Dr. De Kok has been author and/or co-author of more than 25 papers in scientific journals and has
presented many lectures and posters at international symposia and workshops.
Dr. De Kok was the chairman of the 1st European Pesticide Residue Workshop (EPRW’96), held in
Alkmaar, The Netherlands, June 1996. He is still a member of the Scientific Organising Committee
of the biannual EPRW.
Dr. De Kok has cooperated in a EU Quality Control Project resulting in an EU document “Quality
Control Procedures for Pesticide Residues Analysis” (Guidelines for Residues Monitoring in the
EU), that has been revised biannually and he was a member of the scientific/organising committee
of EU Workshops on Coordinated Analytical Quality Control (for Pesticide Residue Analysis),
held in Oeiras (Lisbon), Portugal (September 1997), Athens, Greece (November 1999), York, UK
(July 2003) and Stockholm, Sweden (December 2005).
Dr. De Kok is also a member of the Advisory and Scientific Committee for EU Proficiency Testing
for EU Member State laboratories submitting pesticide residue data as part of the EU Monitoring
programme for pesticide residues in fruits and vegetables.
Dr. De Kok has been participating in two other EU SMT projects on “Organophosphorus Pesticides
in Cereals” and “Intercomparison study of three CEN extraction methods for pesticide residue
analysis’, respectively, and he has co-organised two collaborative studies for the validation of
(draft) CEN-standardised methods for the analysis of N-methylcarbamate pesticides and
benzimidazole fungicides, respectively. Both methods were developed in the Pesticide Analysis
Department of the former Alkmaar Food Inspection Service (now VWA).
He is participating as an governmental liason, experienced pesticide analysis laboratory in a 2-year
EU Alfa-programme project “EUROLANTRAP” (The development of fast and cost-effective
harmonized analytical methods for the determination of pesticides residues in fruits, vegetables and
cereals, to be applied for import and export control, in order to reduce trade barriers and the health
risks for consumers) between 3 Latin-American and 3 European universities, promoting the
exchange of Professors, tutors,Master and Ph.D. students between LA and Europe.
He was co-author of the well-known Dutch Manual “Analytical Methods for Pesticide Residues in
Foodstuffs” (6 th Edition, 1996, General Inspectorate for Health Protection, The Hague, The
Netherlands), to which his laboratory contributed many advanced multi-residue methods.
Most recent literature references:
1. A. de Kok, M. Hiemstra and C.P. Vreeker
Improved cleanup method for the multiresidue analysis of N-methylcarbamates in grains, fruits and
vegetables by means of HPLC with post-column reaction and fluorescence detection
Chromatographia, 24 (1987) 469-476.
2. A . de Kok, M. Hiemstra and C.P. Vreeker
Optimization of the postcolumn hydrolysis reaction on solid phases for the routine high-performance liquid
chromatographic determination of N-methylcarbamate pesticides in food products
J. Chromatogr., 507 (1990) 459-472.
3. A. de Kok, M. Hiemstra and U. A. Th. Brinkman
Low ng/l-level determination of twenty N-methylcarbamate pesticides and twelve of their polar metabolites
in surface water via off-line solid-phase extraction and high-performance liquid chromatography with postcolumn
reaction and fluorescence detection
J. Chromatogr., 623 (1992) 265-276.
4. A. de Kok and M. Hiemstra
Optimization, automation, and validation of the solid-phase extraction cleanup and on-line liquid
chromatographic determination of N-methylcarbamates in fruits and vegetables
J. AOAC Int., 75 (1992) 1063-1072.