A Comparative Analysis on the Environmental Impact of Selected Methods for Determining the Profile of Fatty Acids in Cheese.

The fatty acid profile of cheese influences its sensory parameters, such as color, texture, or flavor. Examining the fatty acid profile also helps to assess the nutritional value of the cheese that is being tested. However, the determination of fatty acids in cheese samples is a multi-stage and time-consuming task. In addition, large amounts of toxic organic solvents are used to prepare samples for analysis purposes. This paper presents the results of a study to determine the fatty acid profile of yellow cheese samples. Six different methods of sample preparation were compared for analysis purposes. The profile of fatty acids was determined using gas chromatography with flame ionization detection (GC-FID). The study showed significant differences (p > 0.05) in the resulting fatty acid profile between the methods used. It was found that the most reliable fatty acid profile results were obtained using methods derived from the Folch method. In addition, tools such as the Analytical Eco-Scale tool and the Analytical Greenness Metric for Sample Preparation (AGREEprep) tool were used to assess the greenness of the methods used. In the case of the Analytical Eco-Scale tool, all six methods scored 'acceptable green analysis' with scores ranging from 61 to 73. However, an evaluation of methods using the AGREEprep metric showed that the results of the methods (0.13-0.27) did not show the "greenness" of the analytical methods.

Comparison of the Effectiveness and Environmental Impact of Selected Methods for the Determination of Fatty Acids in Milk Samples.

Determination of the fatty acid profile in milk samples is one of the most important in food analysis. There are many methodologies for FA determination. The conventional procedure for determining the FA composition of milk is isolation of fat or indirect methylation, trans-methylation, extraction of fatty acids, and analysis by gas chromatography. In this study, eight methods based on alkaline methylation were compared for the analysis of fatty acids in cow's milk. The response factors (RF) for GC analysis using FID were calculated. For most acids, RFs were close to 1, with the exception of short-chain fatty acids (C4:0-C8:0). To facilitate the selection of the method for the determination of fatty acids in milk samples, the methods were assessed using the environmental assessment tools of the analytical procedure: the Analytical Eco-Scale, Green Analytical Procedure Index (GAPI), and Analytical Greenness for Sample Preparation (AGREEprep). The method based on direct milk methylation received the highest scores. Omitting the lipid separation step has an impact on reducing the quantity of used toxic chemicals and reagents, and produces a smaller amount of waste, a much higher throughput, and a reduced cost analysis.

Microplastic in the Baltic Sea: A review of distribution processes, sources, analysis methods and regulatory policies.

Microplastics pollution is an issue of great concern for scientists, governmental bodies, ecological organisations, and the general public. Microplastics pollution is widespread and is a great environmental problem on account of its potential toxicity for marine biota and human health. Today, almost all the world's seas and oceans are polluted with microplastics. The Baltic Sea is a semi-enclosed reservoir of brackish water and is a hotspot for contamination in terms of eutrophication and the presence of organic matter. Microplastics are quite intense, based on data from studies of marine litter and microplastics in the Baltic Sea. The number of microplastics in the Baltic Sea water is 0.07-3300 particles/m3, and in sediments 0-10179 particles/kg. These amounts prove that the waters and sediments of the Baltic Sea are heavily contaminated with microplastics. This article provides a comprehensive review of the microplastic origins and transport routes to the Baltic Sea. The data is presented as the concentration of microplastics in surface waters, sediments, and sea sand. The extraction methods used and the microplastics techniques are also presented. The possibilities and limitations of water and sediment sampling methods for microplastics determination were summarised, taking into account sampling tools, volume and depth. Extraction, separation, filtration, and visual sorting are outlined as sample preparation techniques for microplastic analysis. This review also focuses on the problems of obtaining data relevant to the development of the mathematical models necessary to monitor trends in the spread of microplastics in the Baltic Sea. Finally, several important laws and policies, which are in place in the Baltic States to control and manage microplastic pollution in the region, are highlighted.

Determination of Benzophenones in Water and Cosmetics Samples: A Comparison of Solid-Phase Extraction and Microextraction by Packed Sorbent Methods.

Benzophenones (BPs) are extensively used in a wide variety of cosmetic products and other materials (e.g., textiles or plastics) to avoid damaging effects of UV radiation. In the present work, we compared two extraction methods for the determination of BPs, namely, 2,4-dihydroxybenzophenone (BP-1), 2-hydroxy-4-methoxybenzophenone (BP-3) and 2,2-dihydroxy-4-methoxybenzophenone (BP-8), in water and cosmetics samples. The following extraction methods were used for the research: solid-phase extraction (SPE) and microextraction by packed sorbent (MEPS), whereas analysis was performed by gas chromatography with mass spectrometric detection. A comparison between the methods indicates that the MEPS technique(s) can be reliably used for analysis of BPs (sunscreen residue) in water samples and cosmetic samples with satisfactory results. This microextraction technique is cheap, easy, quick to implement, and consumes small amounts of solvents. On the other hand, the main advantage of the SPE method are low detection limits for the determination of BPs in water samples, i.e., from 0.034 to 0.067 µg L-1, while, for the MEPS method, LODs were at the level of 1.8-3.2 µg L-1. For both methods, the recoveries of BPs were 96-107% and 44-70% for water and cosmetics samples, respectively. The presented methods are suitable for use in cosmetics quality control and environmental pollution assessment.

An Overview of the Analytical Methods for the Determination of Organic Ultraviolet Filters in Cosmetic Products and Human Samples.

UV filters are a group of compounds commonly used in different cosmetic products to absorb UV radiation. They are classified into a variety of chemical groups, such as benzophenones, salicylates, benzotriazoles, cinnamates, p-aminobenzoates, triazines, camphor derivatives, etc. Different tests have shown that some of these chemicals are absorbed through the skin and metabolised or bioaccumulated. These processes can cause negative health effects, including mutagenic and cancerogenic ones. Due to the absence of official monitoring protocols, there is an increased number of analytical methods that enable the determination of those compounds in cosmetic samples to ensure user safety, as well as in biological fluids and tissues samples, to obtain more information regarding their behaviour in the human body. This review aimed to show and discuss the published studies concerning analytical methods for the determination of organic UV filters in cosmetic and biological samples. It focused on sample preparation, analytical techniques, and analytical performance (limit of detection, accuracy, and repeatability).

Highly Effective Sensitizers Based on Merocyanine Dyes for Visible Light Initiated Radical Polymerization.

The 5-(4-substituted-arylidene)-1,3-dimethylpyrimidine-2,4,6-triones were tested as visible light sensitizers for phenyltrialkylborate salts applied to initiate polymerization processes. The initiation occurs as a result of photoinduced electron transfer from the borate salt to the merocyanine dye. The main factor that facilitates the step of the reaction is the free energy change for electron transfer. Its value is favorable according to the reduction properties of the dyes influenced by the type of amino groups and the oxidation potentials of the borate salts. The observed bleaching of the dyes during photopolymerization affects the yield of both the alkyl radical and sensitizer-based radical formation and thus the efficiency of the photopolymerization.

Development of a Single-Drop Microextraction with Derivatization Procedure for Analysis of Volatile Fatty Acids in Water Samples.

A single-drop microextraction (SDME) was developed for the analysis of volatile fatty acids (VFAs) (C2-C7) in water by gas chromatography (GC) with flame ionization detection. The significant parameters affecting the SDME performance such as selection of microextraction solvent, extraction time, stirring rate, sample pH and temperature, and ionic strength were studied and optimized. To lower limits of detection, derivatization of VFAs by N-methyl-N-(tert-butyldimethylsilyl)trifluoroacetamide (MTBSTFA) was performed. The method developed requires very short time of extraction and derivatization (13 min) and it is characterized by a good precision (max RSD = 11.4%), linearity and relatively low limits of detection (from 8.3 mg L-1 for acetic acid to 0.008 mg L-1 for heptanoic acid). The results of the SDME in combination with GC show promising potential for the analysis of VFAs in water samples.

Determination of linoleic acid in toothpaste by gas chromatography with flame ionization detection.

A new method for the determination of linoleic acid (LA) in toothpaste by a routine analysis has been proposed. Studies were based on the ISO 5509 procedure, which was modified for the purpose of LA determination in the toothpaste. Gas chromatography (GC) was employed for the qualitative and quantitative determination of linoleic acid methyl ester. The content of LA (5.31%) in sunflower oil added to the toothpaste composition (0.5%) was determined, and then the optimization studies for the determination of LA in the toothpaste samples were carried out. The relative standard deviation (RSD) of the procedure developed was 9.96% (n = 9). The quantitative analysis showed that the content of LA in the toothpaste samples studied was 0.0258 +/- 0.0011%. The detection limit of LA in toothpaste was approximately 0.001%.

Application of Headspace Solid-Phase Microextraction for Determination of Chloro-Organic Compounds in Sewage Samples.

Solid phase microextraction (SPME) has been optimized and applied to the determination of the volatile halogenated compounds (VHCs) and semi-volatile halogenated compounds (SVHCs). Three types of SPME fiber coated with different stationary phases (PDMS-100 mum, CAR/PDMS-75 mum, PDMS/DVB-65 mum) were used to examine their extraction efficiencies for the compounds tested. Experimental parameters such as the selection of SPME coatings, extraction time, and addition of salts were studied. The carboxen-polydimethylsiloxane (CAR/PDMS) fiber appears to be the most suitable for the determination of VHCs. Analytical parameters such as linearity, limit of detection, and precision were also evaluated. Application of ECD detector for the determination of VHCs and SVHCs allows their determination on the low concentration level, ranging from 0.005 to 0.8 mug/L(-1). The HS-SPME-GC/ECD procedure gave good analytical precision expressed as relative standard deviation (RSD) (ranged from 5.08% to 8.07%) for a concentration level of 5 mug/L(-1) and good linearity (r(2) > 0.98) in a wide calibration range. The applied HS-SPME-GC/ECD method was found to be a quick and effective technique for the determination of microtrace amounts of volatile and semi-volatile halogenated compounds in samples containing high amounts of various organic compounds.

Determination of fluoride in toothpaste using headspace solid-phase microextraction and gas chromatography-flame ionization detection.

A new method for determination of fluoride in toothpaste employing the headspace solid-phase microextraction (HS-SPME) followed by gas chromatography/flame ionization detection (GC/FID) has been proposed. It is a development of the method for determination of fluoride using trimethylchlorosilane (TMCS) as the derivatization reagent to form trimethylfluorosilane (TMFS), with the liquid/liquid extraction (LLE) step replaced by HS-SPME. To introduce the latter, it was necessary to determine the conditions of the reaction and to optimize the two stages of the SPME procedure: extraction and desorption. The parameters of the SPME analysis using carboxen/polydimethylsiloxane (CAR/PDMS) fiber were defined and compared with the corresponding ones for the LLE method, used as a reference. Also, these two methods were compared with respect to their linearity, precision, and accuracy. Results from toothpaste analyses using these two methods were highly correlated, indicating the potential to use the SPME extraction as an inexpensive and solventfree alternative to the LLE method.

Determination of epichlorohydrin in water and sewage samples.

The simple, quick and effective methods for the analysis of epichlorohydrin (ECH) in water and sewage samples with the use of gas chromatography have been presented. From among all the methods developed, the procedures for monitoring drinking-water quality and the methods which allow the determination of epichlorohydrin in sewage samples have been selected. The limits of ECH detection have been determined by direct aqueous injection (DAI) into the chromatographic column and an analysis with the application of a flame ionization detector (FID), a mass spectrometry detector (MS), an electron capture detector (ECD) and atomic emission detection (AED) detectors. The method allows the determination of ECH in water samples at the concentration level of 0.1mgl(-1). Moreover, the developed methods of water samples preparation for chromatographic analysis using the following extraction methods: headspace (HS), stripping with adsorption on solid phase, liquid-liquid extraction (LLE), solid phase extraction (SPE) and solid phase microextraction (SPME) have been evaluated. The limits of ECH detection for each procedure with the application of gas chromatography (GC) combined with various detectors have been determined and their statistical evaluation has been presented. The SPME method allowed us to determine ECH in water samples at the concentration levels of 1.0ngl(-1). The results of studies on the choice of the selective methods allowing ECH analysis in sewage samples have been demonstrated. The applied SPME method was found to be a quick and effective technique to determine micro trace amounts of ECH in samples containing high amounts of various organic compounds.