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Highlights: [•] An efficient method for determination of cocaine in human liver is proposed. [•] The method employs solid–liquid extraction with low temperature partitioning. [•] Variables as pH, volume of the solvent, use of PSA and NaCl, were evaluated. [•] The use of PSA and NaCl does not influence the recovery of cocaine from liver. [•] The method was validated and applied to the analysis of eight real samples from drug users. [Copyright &y& Elsevier]

The efficiencies of two conventional domestic procedures (immersion in pure water and detergent solution at 0.25 and 1%) and two treatments using ozone (immersion in water with bubbling O 3 and immersion in ozonated water, both at 1 and 3 mg L−1) were evaluated for the removal of residues of the fungicides azoxystrobin, chlorothalonil and difenoconazole in tomatoes. The fungicides were sprayed on the fruits at the recommended concentration for the crop. The residues in the tomatoes and in the washing solutions were determined by extraction with low-temperature partition techniques and analysis by gas chromatography. More concentrated solutions were more effective in removing pesticide residues. The water bubbled with ozone at 3 mg L−1 was the most efficient treatment for the removal of fungicides, reaching a reduction of 70–90% of the residues. However, the treatments with the lowest concentration of ozone had lower loss of fruit mass during storage. Unlabelled Image • ESL/LTP and ELL/LTP successfully employed for pesticide quantification by GC/ECD. • Immersion in water and detergent solution removed a considerable part of the waste. • Treatments with ozone were more efficient in removing pesticide residues in tomatoes. • The use of ozone during processing and storage increases the shelf-life of the tomatoes. • In general the treatments did not change the quality of the fruits. [ABSTRACT FROM AUTHOR]

Abstract: In this work, a simple and low cost method based on solid–liquid extraction with low temperature partitioning (SLE–LTP) was optimized and validated for the residue analyses of the pesticides thiamethoxam, triadimenol and deltamethrin in pineapple samples using gas chromatography with electron capture detector (GC-ECD). The SLE-LTP technique was proven satisfactory with recoveries up to 90% and linear chromatographic response for the analytes, ranging from 0.04 to 1.30 μg g−1 with correlation coefficients above 0.99. The limits of quantification for the pesticides were lower than the allowed maximum limits of residues established for these pesticides in pineapple by the European Union. [Copyright &y& Elsevier]

Abstract: In this work, a simple and low cost method, based on solid–liquid extraction with low temperature purification (SLE–LTP), was optimized and validated for the determination of chlorpyrifos, λ-cyhalothrin, cypermethrin and deltamethrin in tomato samples. The analyses were performed by the GC–ECD and confirmed by the GC–MS. The method requires 4g of tomato and an extraction mixture (8.0mL acetonitrile, 0.5mL water and 1.5mL ethyl acetate), which was established by mixture experimental design. After optimization, pesticide recovery rates ranged from 79% to 97%, with a standard deviation of less than 5%. The SLE–LTP analytical characteristics were compared very favorably to the matrix solid phase dispersion technique, which used ethyl acetate and Florisil for extraction. [Copyright &y& Elsevier]