Duplicate sampling reproducibility of atmospheric residues of herbicides for paired pan and high-volume air samplers

The reproducibility of collection of atmospheric residues of the herbicides 2,4-D and triallate as bulk (wet plus dry) deposition samples by paired pa n samplers and as particulate (filter) and vapour (PUF/XAD-2 resin cartridg e) samples by paired high-volume air samplers was determined. Variability o f herbicide concentrations in paired bulk deposition samples was within 25% for 65 and 80% of the samples for 2,4-D and triallate, respectively, with approximately 90% of the paired samples being within a factor of 2 for both herbicides. The vapour samples of 2,4-D and triallate showed similar repro ducibilities. The highest reproducibility was observed for the filter sampl es with 92% of the paired data sets for 2,4-D being within 25% variability. No triallate was detected in the filter samples. (C) 2000 Published by Els evier Science Ltd. All rights reserved.