English Abstract Sorption of pesticides by aquifer materials was tested
by laboratory column experiments. Five pesticides (mecoprop, dinoseb,
atrazine, propachlor and 1,3-dichloropropene) and one degradation product of
dichloropropene, chloroallylalcohol, were tested on three different aquifer
materials. Retardation factors determined from the results ranged from 1 to
1.28, indicating the sorption was always very low. Calculated partition
coefficient and K om-values ranged from 0 to 0.063 and 0 to 74,
respectively. Mecoprop and chloroallylalcohol sorbed to non of the tested
aquifer materials while dinoseb and dichloropropene to all the three tested
aquifer materials sorbed. Sorption was much lower than found with batch
experiments and only slightly lower than found with in situ experiments K
om-values of aquifer materials determined by column experiments are in the
same order of magnitude as found for topsoils. This indicates that values
found for topsoils can be extrapolated to aquifer materials and that organic
matter is the most important parameter for sorption of pesticides by soils.
Column experiments and in situ experiments seem to be the best methods to
study sorption on aquifer materials.
