Comparison of the leaching behaviour of two maize herbicides: atrazine and sulcotrione

Abstract

-In a soil column experiment under outdoor conditions, we monitored the fate of 14 C-ring-labelled sulcotrione and atrazine in water percolates and in the ploughed horizon of a sandy-silty soil. The application rates were 1000 and 450 g·ha -1 , respectively, for atrazine and sulcotrione. Two months after treatment, the cumulative amounts of herbicide residues leached from the soil were 14.5% and 7% of the applied radioactivity for sulcotrione and atrazine, respectively. The maximum percolate concentrations for each herbicide were observed during the first month following application; 120 µg·L -1 and 95 µg·L -1 for sulcotrione and atrazine, respectively. After 2 weeks, 78% of the sulcotrione and atrazine was extractable from the soil, whereas after two months only 10% and 4%, respectively, could be extracted. The maximum sulcotrione and atrazine contents in the first ten centimetres of soil were identical. For both molecules, the content of non-extractable residues was low, being around 15%. The sulcotrione seems to be a more mobile product than the atrazine. Even if much smaller leachate concentrations would be expected to impact groundwater than those found in this study, the classification of the molecules would stay the same. soil columns / pesticide fate / bound residues / soil and water pollution

Simple, Rapid and Sensitive Electrochemical Method for the Determination of the Triketone Herbicide Sulcotrione in River Water Using a Glassy Carbon Electrode

“…However, in 3‐fold excess, the determination of sulcotrione appeared not to be reliable anymore in the presence of mesotrione because a shift of peak potentials was observed combined with a broadening of the signals which led to overlapping and erroneous enumeration of the peak current (Figure 5). The recommended dose for sulcotrione per hectare is less than 450 g 21 and for mesotrione less than 200 g 22, their content in natural water is probably not supposed to occur in a ratio mesotrione:sulcotrione 3 : 1 or more in case that both pesticides were applied. This fact indicates that the proposed analytical technique may be used for the reliable determination of sulcotrione.…”

Integral Study of Atrazine Behaviour in Field Lysimeters in Argentinean Humid Pampas Soils

“…The high water content of the soil favors atrazine transport, associated with gravity drainage (Beck et al, 1996), piston-type water flow (Sorenson et al, 1994) reduces atrazine retention (Koskinen and Rochette, 1996). Besides, the condition of "fresh residues" favors atrazine mobility (Beck et al, 1996;Neurath et al, 2004;Cherrier et al, 2005). In P4 (31-110 d after application) these percentages decreased to 0.01 and 0.005% for Pergamino and Junín, respectively.…”

“…Use of lysimeters allows for integral studies of pesticide behavior in soil. In studies at semi-field scale with partially controlled conditions, is possible to incorporate aspects related to crop such as crop development, fertilization, crop sequence, method of water supply, cultivation systems (Dousset et al, 1995;Isensee and Sadeghi, 1996;Clay et al, 1998;Cherrier et al, 2005). Many of these studies have been conducted with irrigation, thus allowing for determination of changes in the atrazine residues availability in terms of the time passed since application and the water supply (Beck et al, 1996).…”