Distribution and persistence of carbaryl in some terrestrial and aquatic components of a forest environment |
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Authors: | K M S Sundaram S Y Szeto |
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Institution: | 1. Agriculture Canada, Canadian Forestry Service, Forest Pest Management Institute , 1219 Queen Street East, P.O. Box 490, Sault Ste. Marie, Ontario, P6A 5M7;2. Agriculture Canada, Research Station , 6600 N.W. Marine Drive, Vancouver, B.C., V6T 1X2 |
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Abstract: | Abstract An oil‐based formulation of carbaryl (1‐naphthyl N‐methyl‐carbamate) (Sevin‐2‐Oil) was applied twice by a fixed‐wing aircraft at a dosage rate of 280 g of A.I./ha/application to a coniferous forest near Allardville, New Brunswick. The highest concentrations of the chemical in fir foliage, litter and forest soil 1 h after application were respectively 4.20, 1.21 and 0.59 ppm (fresh weight). The residues dissipated rapidly and the DT50 values obtained from the depletion curves were 2.3 d for foliage and 1.5 d for litter and soil samples. Very low levels (<0.1 ppm) of carbaryl persisted in foliage and litter beyond the 10 d sampling period. The maximum residue level found in stream water was 0.314 ppm and more than 50% of it had dissipated within 1 h. Low but detectable levels (0.001 ppm) of the chemical persisted in water until the end of the 10 d sampling period. Sediment samples contained a maximum level of 0.04 ppm, which dissipated below the detection limit within 5 h. Brook trout and slimy sculpins captured in the stream 1 d after the spray contained on average about 0.04 ppm of carbaryl and none of it was found in 3 d postspray samples. |
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Keywords: | Carbaryl Sevin‐2‐Oil residues fir foliage litter soil water sediment fish droplet density and size |
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