Easy and fast extraction methods to determine organochlorine pesticides in sewage sludge, soil, and water samples based at low temperature

Abstract

Organochlorine pesticides present in sewage sludge can contaminate soil and water when they are used as either fertilizer or agricultural soil conditioner. In this study, the technique solid-liquid extraction with low temperature purification was optimized and validated for determination of ten organochlorine pesticides in sewage sludge and soil samples. Liquid-liquid extraction with low temperature purification was also validated for the same compounds in water. Analyses were performed by gas chromatography-mass spectrometry operating in the selective ion monitoring mode. After optimization, the methods showed recoveries between 70% and 115% with relative standard deviation lower than 13% for all target analytes in the three matrices. The linearity was demonstrated in the range of 20 to 70 µg L, 0.5 to 60 µg L, and 3 to 13 µg L, for sludge, soil, and acetonitrile, respectively. The limit of quantification ranged between 2 and 40 µg kg, 1 and 6 µg kg, and 0.5 µg L for sludge, soil, and water, respectively. The methods were used in the study of pesticide lixiviation carried out in a poly vinyl chlorine column filled with soil, which had its surface layer mixed with sludge. The results showed that pesticides are not leached into soil, part of them is adsorbed by the sewage sludge (4-40%), and most pesticides are lost by volatilization.

Optimization and Validation of the Miniaturized Solid-Liquid Extraction with Low Temperature Purification (SLE-LTP) Method for Determining Fluopyram in Sandy, Clayey and Medium-Textured Soil

“…In addition to reducing the signal intensity of the analyte studied, the use of ethyl acetate in the extractor phase also intensified the matrix effect, as evidenced by the high recovery percentages, as shown in Table 1. These results are in agreement with those found by Silva et al 17 who achieved high recovery rates using acetonitrile in the miniaturized version of liquid-liquid extraction with low temperature partition to determine pesticides in biological matrices; and Mesquita et al, 14 who used acetonitrile in SLE-LTP to study various pesticides in soil samples.…”

“…[6][7][8][9][10][11][12] Although these methodologies have proven to be very efficient and sensitive, the development of new extraction methods which can be simpler, easier to perform, sensitive, efficient and cheaper is recommended. In this sense, previous works [13][14][15][16] have shown that solid-liquid extraction with low temperature purification (SLE-LTP) has gathered these characteristics when applied to other environmental contaminants. Therefore, a miniaturized variation of this methodology was recently optimized and validated to monitor pesticides in biological matrices.…”

Extraction Method for Determining Florpyrauxifen-benzyl Herbicide in Soil

“…In this sense, previous works have shown that solid-liquid extraction coupled with low-temperature purification (SLE-LTP) has met these characteristics when applied to other environmental contaminants. 15,16 One of the main advantages of this methodology is the extraction and cleaning in a single step.…”

Optimization and validation of liquid–liquid extraction with low-temperature purification (LLE-LTP) for determining fluopyram fungicide in water samples using HPLC-DAD

“…In this period, the matrix and its components are entrapped into the structure of ice, while the target analyte migrates to the liquid organic phase, and generally no additional clean-up step is necessary. 11,12 Therefore, the extract may be analyzed by analytical techniques, such as liquid chromatography or gas chromatography. However, to the best of our knowledge, no studies employing this methodology for determining uopyram in water samples have been completed so far.…”