Simultaneous Determination of Selected Insecticides and Atrazine in Soil by Mae–GC–ECD

Abstract

Abstract:The procedure for simultaneous extraction from soil and determination by means of GC-ECD insecticides: aldrin, dieldrin, endrin and herbicide: atrazine was worked out. The proposed GC-ECD technique provides limits of detection in range 12 μg/mL -18 μg/mL and 2 μg/mL, for insecticides and atrazine, respectively. Two different types of extraction: microwave assisted extraction (MAE) and ultrasound assisted extraction (UAE) with different solvents were tested to choose the procedure that provides the highest recoveries of analytes and low detection limits, typical for trace analysis (100 ppm or 100 mg/g, IUPAC). On the basis of recoveries and precision both extraction methods were compared. The insecticides recovery from soil samples obtained by UAE were in range 40-85%, coeffi cient of variation (CV): 1.3-5.0%, whereas for atrazine recovery was below 15% (CV: 8-18%). The most effi cient and precise extraction procedure turned out to be MAE with n-hexane: acetone. The recoveries were in range 70-85% for insecticides and 84% for atrazine, CV: 0.4-2.2% and 5.3% for insecticides and atrazine, respectively. The presented MAE-GC-ECD procedure enables extraction and determination of aldrin, dieldrin, endrin and atrazine in soil samples with high recoveries, precision and limits of detections in range 6 ng/g -8 ng/g in the case of insecticides and 1.5 ng/g for atrazine.The MAE-GC-ECD procedure was applied for the above mentioned pesticides determination in environmental samples. Soils were collected in agricultural as well as rural areas in Poland. In all cases atrazine was determined in concentration range: 0.0187 mg/g -0.1107 mg/g. Aldrin and dieldrin was detected in soil samples from two locations.

The interaction between atrazine and the mineral horizon of soil: a spectroscopic study

“…To explain these interactions, three parallel series of soil samples were collected in forest areas from the upper layer (organic horizon), which contains humus, as well as from a depth of 1 m, where the concentration of humus is considerably lower than in the organic horizon. Low recovery of atrazine from soil samples obtained using ultrasound-assisted extraction was reported in earlier studies (Baranowska et al 2006;Barchanska et al 2013). The effectiveness of extraction was not influenced by the type of solvent.…”

“…The literature overview indicates that the atrazine recovery from soil samples is strongly influenced by the extraction technique, the pH of the soil and the herbicide's interaction with the organic and inorganic compounds in the soil matrix (Gonzalez-Pradas et al 2003;Urena-Amate et al 2005;Barchanska et al 2013). The sorption and desorption processes of atrazine on soil components play an important role in its environmental behaviour.…”

“…Finally, the extract was completely dried to a dryness solid at room temperature. Before the chromatographic analysis, it was dissolved in 1 mL of hexane (Barchanska et al 2013). …”

“…Other researchers explain the formation of well-known non-extractable chloro-s-triazine residues in soil by chemical binding to HA by heteroatomic bonds after the substitution of a chlorine atom (Neto et al 1994;Yu and Cole 1997;Davies and Jabeen 2003;Zupancic-Kralj, 2005, Prosen et al 2007). Many researchers have demonstrated the influence of the mineral components of soil on the sorption of atrazine (Davies and Jabeen 2003;GonzalezPradas et al 2003;Lesueur et al 2008;Feria-Reyes et al 2011;Barchanska et al 2013;Prado et al 2014). SiO 2 and Al 2 O 3 are the predominant minerals present in soil.…”

“…The literature review and the results of our experiments (Barchanska et al 2013) prompted us to carry out a more comprehensive study on the interaction between atrazine and selected mineral compounds in soil.…”