title: Residues of chlorpyrifos-methyl in balsam fir foliage, forest litter, soil, stream water, sediment and fish tissue after double aerial applications of Reldan.
abstract: Chlorpyrifos-methyl was applied twice at 70 g A.I./ha by means of a fixed-wing aircraft to a mixed coniferous forest near Allardville, New Brunswick. Residue in balsam fir foliage was highest (1 ppm wet wt) 1 hr after spraying and rapidly declined to about 30% within 1 day, but persisted at a very low level (0.03 ppm wet wt) for 125 days. Current year's foliage contained a higher level of residue than old foliage. Chlorpyrifos-methyl persisted longer in forest litter than in soil. After 125 days, trace amounts (less than 6 ppb wet wt) were still found in litter but were not detected in soil. In stream water the residue dissipated very rapidly; more than 90% disappeared 3 hours after the second application and were not detected after 4 days. Low-level residue (less than 0.1 ppm wet wt) was present in the sediment and persisted for 10 days. Although brook trout and slimy sculpin captured in the stream within 3 days of the second application contained residues (less than 0.05 ppm fresh wt) none were detected in any fish captured, 9 and 47 days later.
mesh_terms: D000818:Animals; D004390:Chlorpyrifos / Q000031:analogs & derivatives* / Q000378:metabolism; D005399:Fishes / Q000378:metabolism*; D010573:Pesticide Residues / Q000032:analysis*; D010944:Plants / Q000032:analysis*; D012987:Soil / Q000032:analysis*; D014867:Water / Q000032:analysis*
chemical_list: D010573:Pesticide Residues; D012987:Soil; D014867:Water; D004390:Chlorpyrifos; C007031:chlorpyrifos-methyl