POTENTIAL DISSIPATION OF ATRAZINE IN THE SOIL UNSATURATED ZONE - A COMPARATIVE-STUDY IN 4 EUROPEAN COUNTRIES

A European-wide project has been undertaken to establish the potential for dissipation of atrazine in the soil subsurface environment. Sampl es were obtained, avoiding contamination, in four countries (Belgium, Greece, Hungary and UK) and laboratory studies carried out. In order t o make comparisons between results from each laboratory, a ring experi ment was carried out using common methodology for sampling, extraction and analytical techniques. Subsurface materials from each country wer e distributed to the other countries. Atrazine dissipation was determi ned in each country for all materials under the same laboratory condit ions. The results of this comparative study showed generally good agre ement between all laboratories. Significant potential microbiological dissipation was detected in certain samples. Where differences occurre d between laboratories this was attributed to small, spatially heterog eneous microbial populations in the subsurface materials.