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R Hindle

Publications and source records attributed to R Hindle.

7 recordsLinked to original sources

Residues of nonylphenol in spruce foliage, forest soil, stream water and sediment after its aerial application.

Nonylphenol, a major component of the Matacil (aminocarb) formulation, was mixed with insecticide diluent 585 and applied at 0.47 l/ha by a fixed-wing aircraft to a mixed coniferous forest in Algoma District, Ontario. Residues in white spruce foliage were the highest 1 h after spraying (18.90 ppm) and declined to 60% in the next two hours. After 30 days only 3% of the highest concentration recorded was observed. No detectable levels (less than 0.20 ppm) of nonylphenol were found after 62 days. No residues were detected in any forest soil sample collected after spraying. Nonylphenol residues were about 9 ppb in the stream water 1 h after its application and declined to 50% in the next two hours. Only trace amounts (less than 2.0 ppb) were detected after 5 days and no residues were detected in any water sample taken beyond this time. Residues at trace level (less than 0.10 ppm) were detected in only one sediment sample taken 4 hours after spraying.

Chromatography, High Pressure Liquid↗

Evaluation of Amberlite XAD-2 as the extractant for carbamate insecticides from natural water.

A rapid and sensitive analytical technique to quantify carbamate insecticides at nanogram levels is reported using resin column and sorption, and desorption followed by N-P gas-liquid chromatography (GLC) analysis. The carbamates were extracted from natural water by percolation through a column of Amberlite XAD-2, followed by elution with ethyl acetate. The carbamate residues were directly analyzed by GLC with a Tracor Model 702 N-P detector. The recoveries for several carbamates including aminocarb, mexacarbate, carbaryl, propoxur, carbofuran, pirimicarb and methiocarb were from 86 to 108% at 1.0 and 0.01 ppm levels. Only 41 to 58% was recovered for methomyl. The extraction efficiency of Amberlite XAD-2 was pH-dependent as indicated in the extraction of aminocarb. More than 90% of the added aminocarb was recovered from phosphate buffer by the described method at pH 5.0 to 7.5 at 5.0 and 0.5 ppm levels.

Carbamates↗

Determination of N-nitrosodipropylamine in trifluralin emulsifiable concentrates using minicolumn cleanup and gas chromatography with thermal energy analyzer.

A quick method for determining N-nitrosodipropylamine (NDPA) levels in trifluralin emulsifiable concentrate formulations is described. At least 18 samples can be analyzed at one time in a minimum of fumehood space, with up to 90% savings on solvents and materials. A sample aliquot is mixed with a solution containing nitrosamine recovery standards, and nitrosamines are separated by minicolumn cleanup. Internal standard is added directly to the eluate containing the nitrosamines, and levels are determined by gas chromatography with thermal energy analyzer. Recoveries of spiked nitrosamines ranged from 98 to 102%. Coefficients of variation for samples containing less than 0.5 ppm NDPA are less than 13%. Minimum detectable limit, calculated as 3 times the noise, is 0.06 ppm. Comparison with the method formerly used by this laboratory shows no significant difference in the analytical results at 95% confidence limits, and control experiments were performed to ensure that there was no artifact formation of NDPA.

Chromatography, Gas↗