Volatility of Atrazine from Plant, Soil, and Glass Surfaces

Abstract

AbstractVolatility of atrazine (2‐chloro‐4‐(ethylamino)‐6‐isopropylamino‐s‐triazine) from glass, plant, and soil surfaces was determined by passing air above the experimental material through Florisil3 columns. Atrazine volatility was determined by counting the 14C‐atrazine present in the column eluate and that remaining on the treated surfaces.Volatility from 125‐ml glass erlenmeyer flasks was influenced most by the amount of atrazine present. At 40C with an air velocity of 2 liters/min 70% of the applied atrazine was recovered from the florisil columns in 2 days when 1 µg of atrazine was applied; whereas, 10% was recovered when 1,000 µg was applied. Temperature, air velocity, and atrazine purity also affected atrazine volatility. Volatility was 25% greater at 40 than at 20C at an air velocity of 2 liters/min. An increase in air velocity increased atrazine volatility more at 20C than at 40C. Approximately 10% more atrazine was lost from a commercially formulated material than from a technically pure material. Dried plant material lost 18–27% of the applied atrazine in 2 days at 40C. Atrazine (37mM) was also applied in 2 µliter droplets to intact Cirsium arvense (Canada thistle) leaves. Two days after treatment 50% of the activity was located in the Florisil column. Volatility of atrazine from the soil was less than 10% in 2 days at 40C. It was concluded that atrazine volatility is a major factor for atrazine dissipation when applied to foliage but not when applied to the soil.