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Pyrethroids, such as cypermethrin (CYP), are widely employed in agriculture, promoting environmental pollution and the need for efficient decontamination methods. In this study, bacteria from orange crops were explored for CYP biodegradation. Among 40 tested bacterial strains, 20 grew in the presence of CYP and 19 performed statistically significant CYP biodegradation in 5 days (20.5%–97.8%). In addition, 3-phenoxybenzoic acid, the main metabolite from CYP, was quantified ranging from 1.1 mg.L−1 to 32.1 mg.L−1. The five most efficient strains, and consortia composed of 5, 10 and 20 bacteria biodegraded the CYP formulation as sole carbon source in phosphate buffer and in minimum mineral medium. Under optimized conditions determined employing Response Surface Methodology, Bacillus sp. CSA-1 and the consortium composed of 10 strains biodegraded 71.0% and 71.6% CYP in 24 h, respectively. Moreover, metabolite identification enabled the proposal of an extended biodegradation pathway with 29 identified compounds, including different new amide and amine derivatives that expanded the knowledge about the fate of this compound in the environment. Experiments of bioaugmentation in soil using Bacillus sp. CSA-1 and the consortium of 10 bacterial strains resulted in faster CYP biodegradation than natural attenuation, showing that the selection of efficient strains for composing a consortium is an interesting approach for bioremediation of pyrethroids. [Display omitted] • From 40 strains, 20 bacteria grew up and 19 biodegraded cypermethrin at 100 mg.L−1. • The consortium of 10 bacteria biodegraded 71% cypermethrin in 24 h in media. • A cypermethrin biodegradation pathway was proposed with 29 identified compounds. • New amide and amine metabolites from cypermethrin were reported. • Bioaugmentation in soil was faster than natural attenuation. [ABSTRACT FROM AUTHOR]

The pesticides belonging the strobilurin group are among the most common contaminants in the environment. In this work, biodegradation studies of the strobilurin fungicide Pyraclostrobin by bacteria from orange cultivation plots were performed aiming to contribute with the development of a bioremediation method. Experiments were performed in triplicate with validated methods, and optimization was performed by Central Composite Design and Response Surface Methodology. The strains were evaluated in liquid nutrient medium containing 100 mg L−1 of Pyraclostrobin, and decreased concentrations of 61.5 to 100.5 mg L−1 were determined after 5 days at 37 °C and 130 rpm, showing the importance of strain selection. When the five most efficient strains (Bacillus sp. CSA-13, Paenibacillus alvei CBMAI2221, Bacillus sp. CBMAI2222, Bacillus safensis CBMAI2220 and Bacillus aryabhattai CBMAI2223) were used in consortia, synergistic and antagonistic effects were observed accordingly to the employed combination of bacteria, resulting in 64.2 ± 3.9 to 95.4 ± 4.9 mg L−1 residual Pyraclostrobin. In addition, the formation of 1-(4-chlorophenyl)-1 H -pyrazol-3-ol was quantified (0.59–0.01 mg L−1), and a new biodegradation pathway was proposed with 15 identified metabolites. Experiments were also performed in soil under controlled conditions (30 °C, 0–28 days, 100 mg kg−1 pesticide), and the native microbiome reduced the pesticide concentration to 70.4 ± 2.3 mg L−1, whereas the inoculation of an efficient bacterial consortium promoted clearly better results, 57.2 ± 3.9 mg L−1 residual Pyraclostrobin. This suggests that the introduction of these strains in soil in a bioaugmentation process increases decontamination. However, the native microbiome is important for a more efficient bioremediation. Unlabelled Image • Biodegradation of pyraclostrobin by bacteria in growth medium and soil was reported. • New biotransformation pathways were proposed, including 15 intermediate compounds. • Synergistic or antagonistic effects occurred depending of the strains in consortia. • The presence of the soil native microbiome enhanced biodegradation. • The use of efficient strains in soil promoted an increased biodegradation. [ABSTRACT FROM AUTHOR]

Introduction: Pollution has emerged as a significant threat to humanity, necessitating a thorough evaluation of its impacts. As a result, various methods for human biomonitoring have been proposed as vital tools for assessing, managing, and mitigating exposure risks. Among these methods, urine stands out as the most commonly analyzed biological sample and the primary matrix for biomonitoring studies., Objectives: This review concentrates on exploring the literature concerning residual pesticide determination in urine, utilizing liquid and gas chromatography coupled with mass spectrometry, and its practical applications., Method: The examination focused on methods developed since 2010. Additionally, applications reported between 2015 and 2022 were thoroughly reviewed, utilizing Web of Science as a primary resource., Synthesis: Recent advancements in chromatography-mass spectrometry technology have significantly enhanced the development of multi-residue methods. These determinations are now capable of simultaneously detecting numerous pesticide residues from various chemical and use classes. Furthermore, these methods encompass analytes from a variety of environmental contaminants, offering a comprehensive approach to biomonitoring. These methodologies have been employed across diverse perspectives, including toxicological studies, assessing pesticide exposure in the general population, occupational exposure among farmers, pest control workers, horticulturists, and florists, as well as investigating consequences during pregnancy and childhood, neurodevelopmental impacts, and reproductive disorders., Future Directions: Such strategies were essential in examining the health risks associated with exposure to complex mixtures, including pesticides and other relevant compounds, thereby painting a broader and more accurate picture of human exposure. Moreover, the implementation of integrated strategies, involving international research initiatives and biomonitoring programs, is crucial to optimize resource utilization, enhancing efficiency in health risk assessment., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Birolli, Lanças, dos Santos Neto and Silveira.)