Metabolism and Persistence of Atrazine in Several Field Soils with Different Atrazine Application Histories

Abstract

To assess the potential occurrence of accelerated herbicide degradation in soils, the mineralization and persistence of 14 C-labeled and non-labeled atrazine was evaluated over three months in two soils from Belgium (BS: atrazine treated 1973 BC: non-treated) and two soils from Germany (CK: atrazine treated 1986-1989; CM: non-treated). Prior to the experiment, accelerated solvent extraction of bulk field soils revealed atrazine (8.3 and 15.2 µg kg −1 in BS and CK soil), and a number of metabolites directly after field sampling, even in BC and CM soils without previous atrazine treatment, by means of LC-MS/MS analyses. For atrazine degradation studies, all soils were incubated under different moisture conditions (50% maximum soil water holding capacity -WHC max -/slurried conditions).At the end of the incubation, the 14 C-atrazine mineralization was high in BS soil (81% and 83%), and also unexpectedly high in BC soil (40% and 81%), at 50% WHC max and slurried conditions, respectively. In CK soil, the 14 C-atrazine mineralization was higher (10% and 6%) than in CM soil (4.7% and 2.7%), but was not stimulated by slurried conditions. The results revealed that atrazine application history dramatically influences its degradation and mineralization. For the incubation period, the amount of extractable atrazine, composed of residues from freshly applied atrazine and residues from former field applications, remained significantly greater (statistical significance = 99.5% and 99.95%) for BS and CK soils, respectively, than the amount of extractable atrazine in the bulk field soils. This suggests that i) mostly freshly applied atrazine is accessible for a complex microbial community, ii) the applied atrazine is not completely mineralized and remains extractable even in adapted soils, and iii) the microbial atrazine-mineralizing capacity strongly depends on atrazine application history and appears to be conserved on long time scales after the last application.

Spatiotemporal Variation and Risk Assessment of Pesticides in Water of the Lower Catchment Basin of Acheloos River, Western Greece

“…Atrazine and its metabolites can persist in water and soil for decades. Jablonowski et al have demonstrated the high persistence of atrazine and its metabolites in soil [40, 41]. The accumulation of the parent compound in the soil may result in a long-term source of atrazine and its metabolites to ground water or surface waters [42].…”

Influence of Soil Amendment History on Decomposition of Recently Applied Organic Amendments

“…Th e rationale behind this hypothesis was that recalcitrant amendments may require a specialized microbial community, a phenomenon already observed in organic xenobiotics ( Jablonowski et al, 2010), whereas easily decomposable amendments do not. In an incubation experiment, the C and N mineralization of three types of organic amendments, diff ering greatly in their chemical characteristics, were compared aft er their application to soils taken from a long-term fi eld experiment that had received one of the corresponding amendments or no amendment for 35 yr before the current experiment.…”

Extraction method for the determination of atrazine, deethylatrazine, and deisopropylatrazine in agricultural soil using factorial design

“…It is important to inform, that HA was not studied in the present work, owing to its intense interaction with the soil particles, providing lower mobility in soils in comparison with AT, DEA and DIA, and as a result, HA presents low likelihood to contaminate groundwaters and surface waters. The more effective extraction methods were not investigated in this work, for instance PLE, 1,22 that could provide the quantification of the bound fraction. Notwithstanding, the results here presented suggest that the method is suitable for the extraction of the more mobile fraction of AT, DIA and DEA, and possibly for other triazines, which is the most relevant fraction for environmental evaluations.…”

“…A traditional and low cost method that can be used for triazine extraction from soils is soxhlet, that yields efficient extraction, but it is a time and solvent consuming method. 12,19 Because of this, green extraction methods have been proposed, including ultrasonic solvent extraction (USE), 14,19 microwave assisted extraction (MAE), 15,16 supercritical fluid extraction (SFE), 20 extraction of the analytes after the shaking of the sample in the presence of an appropriate solvent, followed by solid phase extraction (SPE), 17 headspace solid-phase microextraction (HS-SPME), 21 pressurized liquid extraction (PLE), 1,12,13,22 besides the development of other miniaturized methods as reported in the literature. 14 These methods usually present appropriate results, however some authors have used a less expensive extraction method, based on a simple shaking with solvents of adequate polarity like acetonitrile or methanol and water, providing acceptable recovery values for the extraction of triazine herbicides from soils; 5,8,19 nevertheless, the extraction time is often a drawback, for instance, Mahía et al, 5 and Delgado-Moreno et al, 19 employed 24 h as extraction time.…”