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Hormones in edible matrices, such as milk, are a subject of concern because of their adverse effects on the endocrine system and cell signaling and the consequent disruption of homeostasis in human consumers. Therefore, the assessment of the presence of hormones in milk as potential endocrine-disrupting compounds is warranted. However, the complexity of milk as a sample matrix and the ultra-low concentration of hormones pose significant analytical challenges. Fabric phase sorptive extraction (FPSE) has emerged as a powerful analytical technique for the extraction of emerging pollutants from complex aqueous matrices. FPSE allows for substantially simplified sample handling and short extraction and desorption times, as well as the decreased use of organic solvents. It is considered a green alternative to traditional extraction methodologies. In this work, the FPSE technique was evaluated to perform the simultaneous extraction of 15 steroid hormones from raw milk without employing any sample pretreatment steps. Clean and preconcentrated hormone solutions obtained from FPSE of raw milk were analyzed using ultra-high-performance liquid chromatography-tandem mass spectrometry to achieve low detection limits, which ranged from 0.047 to 1.242 ng·mL-1. Because of the presence of many interferents in milk, such as proteins, lipids, and sugar, the effect of fat content on the extraction procedure was also thoroughly studied. Additionally, for the first time, the effect of lactose on the extraction of steroid hormones was evaluated, and the results showed that the extraction efficiencies were enhanced in lactose-free samples. Finally, the optimized methodology was applied to commercial samples of cow and goat milk, and no measurable concentrations of the studied hormones were detected in these samples.

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Pharmaceuticals and personal care products (PPCPs) constitute a group of chemicals of concern because of their potential toxicity when reaching aquatic environments. Wastewaters are one of the main pathways of introduction into the environment of the chemical compounds used in PPCPs because, in most cases, wastewater treatment facilities are not 100% efficient in their removal. This problem is accentuated in rural zones and isolated communities where conventional treatment systems are too expensive to build and operate. Waste-stabilization ponds and constructed wetlands (CWs) are natural wastewater treatment systems which are used to improve the quality of sewage from small communities because of their low cost and easy maintenance. There is growing interest in combining the two technologies to make a more robust system, taking into account their respective strengths and weaknesses. In this work, a combined macrophyte pond-CW system was evaluated for the presence at three sampling points (influent, pond effluent and CW effluent) of fifteen steroid hormones and six benzotriazole ultraviolet stabilizers (BUVSs). None of the targeted BUVS compounds were detected in either the influent or effluent, probably because of the particular characteristics of the population served by the wastewater system. In contrast, eight different steroid hormone compounds were detected at concentrations ranging from 17.3 to 247.7 ng·L-1 in influent samples and from 8.1 to 22.1 ng·L-1 in final effluent samples. The pond-CW system showed high elimination rates of steroid hormone residues with average removal efficiencies of over 77%. This efficacy was confirmed in the ecological risk assessment evaluation that was performed. Final effluents showed a low ecological risk associated with steroid hormones in contrast to the medium-high ecological risks found in the influent samples.

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Biomarkers, 25-hydroxyvitamin D3 and 25-hydroxyvitamin D2 , are important indicators of the vitamin D general status and are monitored in several pathophysiological disorders, such as osteoporosis, diabetes, heart disease, etc. A novel ultra-HPLC with MS/MS methodology for the analysis of 25-hydroxyvitamin D derivatives coupled with a very simple and highly rapid sample preparation step was developed. Analytical parameters obtained showed linearity (R(2) ) above 0.999 for both vitamins with accuracies between 95.8 and 102%. The LODs were as low as 0.22 and 0.67 nmol/L for 25-hydroxyvitamin D3 and 25-hydroxyvitamin D2 , respectively. Intra-assay precision (%RSD) was lower than 4.5%, and inter-assay precision (%RSD) was lower than 6.5%. The feasibility of the developed methodology to be applied in clinical routine analysis has been proved by its application in blood samples from non-agenarian patients, patients with familial hypercholesterolemia and patients suffering from age-related macular degeneration.

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This work presents an effective sample preparation method for the evaluation of seven pharmaceutical compounds belonging to different therapeutic classes in purified water from wastewater treatment plants (WWTPs). The target compounds include caffeine (stimulant), nicotine (stimulant), atenolol (beta blocker), metamizole (anti-inflammatory and analgesic), fluoxetine (antidepressant), paraxanthine (stimulant) and clofibric acid (lipid regulator). Solid-phase extraction (SPE) and liquid chromatography-mass spectrometry (LC-MS) were selected as extraction and detection techniques, respectively. A detailed study of the experimental conditions of extraction was performed. Under optimal conditions, recoveries obtained were in the range of 21% to 100%, and the relative standard deviations were below 12%. The detection and quantification limits of the method were in the range 2.2-97.4 and 21.1-324.7 ng L(-1), respectively. The developed method was successfully applied to evaluate the presence of these pharmaceutical compounds in wastewaters samples from wastewater treatment plants located on the Gran Canaria Island (Spain). Most of the compounds were detected at concentrations up to 12.31 µg L(-1) in the WWTP influents that were studied.

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Two non-ionic surfactant mixtures (POLE and Polyoxyethylene 10 Cetyl ether, POLE and Polyoxyethylene 10 Stearyl ether) have been used for microwave-assisted extraction of six organochlorine pesticides from agricultural soils prior to being determined by HPLC-UV. An experimental design was applied for the determination of variables which affect to recovery and to optimize the extraction parameters, surfactant concentration and volume, microwave time and power. Under the optimized conditions, the method was applied to different soil samples in order to analyze the influence of soil characteristics on the pesticides extraction. The results obtained indicate that most of these compounds can be recovered in good yields with RSD lower than 10% and detection limit ranged between 80 and 800 ng g(-1) for the pesticides studied. The proposed method was applied to a reference soil sample and to aged soils.

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A new and fast method for the determination of priority phenols in marine sediment samples by high-performance liquid chromatography using microwave-assisted micellar extraction is optimized. This study is carried out using the nonionic surfactants polyoxyethylene 9 lauryl ether (polidocanol) and genapol X-080 as extractants. Parameters studied include surfactant concentration, solution pH, extraction time, and power. Once the method is optimized, it is applied to different spiked marine sediments from of the Canary Islands coastlines (Spain). The results obtained indicate that a power irradiation of 500 W for 2 min achieved the best extraction efficiency (approximately 100% recovery) and less than 10% relative standard deviation. Detection limits are obtained in the 2-20 microg/g range for the phenols studied. Finally, the proposed method provides a simple, fast, and organic solvent-free procedure to analyze phenols from marine sediment samples.

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A non-ionic surfactant, polyoxyethylene 10 lauryl ether (POLE), was used for the microwave-assisted extraction (MAE) of priority phenolic compounds from soil samples. A central composite design was applied to optimize the extraction parameters, namely, time and power. Under the optimized conditions, the method was applied to different soil samples in order to analyze the influence of soil characteristics on the phenol extraction. Results demonstrated that most of these compounds can be recovered from the soils investigated in good yields (higher than 80%). The standard deviation is lower than 9% (n = 6) for most analytes. Validation of the method by analyzing a reference soil sample containing eight phenols and a comparison with Soxhlet extraction are also reported.

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Microwave-assisted micellar extraction methodology was applied to extract a mixture of 8 organophosphorus pesticides from the cuticle of tomato samples prior to analysis by liquid chromatography with ultraviolet detection. This technique provided very good results and was simple, fast, and environmentally friendly. The pesticides under study were extracted using the nonionic surfactants polyoxyethylene 10 lauryl ether (POLE) and oligoethylene glycol monoalkyl ether (Genapol X-080). The optimal extraction variables to be applied were determined for each surfactant and then compared. POLE proved to be the most suitable for the extraction, with recoveries over 70% in the majority and relative standard deviation values under 4.8%. After validation using a tomato sample enriched with a certified mixture, the proposed method was applied to the analysis of organophosphorus pesticides in lettuce and pepper samples.

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