DUPLICATE SAMPLING REPRODUCIBILITY OF ATMOSPHERIC RESIDUES OF HERBICIDES FOR PAIRED PAN AND HIGH-VOLUME AIR SAMPLERS

Allan J. Cessna1*, Don T. Waite1, Lorne A. Kerr3 and Raj Grover3
1Research Centre, Agriculture & Agri-Food Canada, Lethbridge, AB; Present address: National Water Research Institute, 11 Innovation Blvd, Saskatoon, SK, S7N 3H5 Canada
2Environment Canada, 300-2365 Albert Street, Regina, SK, S4P 4K1, Canada
3Retired, formerly at Research Station, Agriculture & Agri-Food Canada, Regina, SK, Canada

The reproducibility of collection of atmospheric residues of the herbicides 2,4-D and triallate as bulk (wet plus dry) deposition samples by paired pan samplers and as particulate (filter) and vapour (PUF/XAD-2 resin cartridge) samples by paired high-volume air samplers was determined. Variability of 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 two for both herbicides. The vapour samples of 2,4-D and triallate showed similar reproducibilities. The highest reproducibility was observed for the filter samples with 92% of the paired data sets for 2,4-D being within 25% variability. No triallate was detected in the filter samples.