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Marine debris is widely recognized as a global environmental problem. One of its main components, microplastics, has been found in several sea salt samples from different countries, indicating that sea products are irremediably contaminated by microplastics. Previous studies show very confusing results, reporting amounts of microparticles (MPs) in salt ranging from zero to 680 MPs/kg, with no mention of the possible causes of such differences. Several errors in the experimental procedures used were found and are reported in the present work. Likewise, 21 different samples of commercial table salt from Spain have been analyzed for MPs content and nature. The samples comprise sea salts and well salts, before and after packing. The microplastic content found was of 50–280 MPs/kg salt, being polyethylene-terephthalate (PET) the most frequently found polymer, followed by polypropylene (PP) and polyethylene (PE), with no significant differences among all the samples. The results indicate that even though the micro-particles might originate from multiple sources, there is a background presence of microplastics in the environment.

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Emissions of low molecular weight aldehydes (LMWAs) from deep-frying of extra virgin olive oil, olive oil, and canola oil (control) were investigated at two temperatures, 180 and 240 degrees C, for 15 and 7 h, respectively. The oil fumes were collected in Tedlar bags and then analyzed by gas chromatography-mass spectrometry. Seven alkanals (C2-C7 and C9), eight 2-alkenals (C3-C10), and 2,4-heptadienal were found in the fumes of all three cooking oils. The generation rates of these aldehydes were found to be dependent on heating temperature, showing significant increases with increases in temperature. The LMWA emissions from both kinds of olive oils were very similar and were lower than those observed from canola oil under similar conditions. These results suggest that frying in any type of olive oil, independent of its commercial category, will effectively decrease the generation of volatile aldehydes in the exhaust. This fact is important because less expensive refined olive oil is usually used for deep-frying operations, whereas extra virgin olive oil is usually used as salad dressing.

According to the latest research, marine products have the greatest potential for microplastic (MPs) contamination. Therefore, their presence in terrestrial food has not managed to attract much attention—despite the fact that in the future they may represent a serious environmental risk. Research conducted in Europe and the US has indicated the presence of MPs in tap water, bottled water, table salt, honey, beer and snails for human consumption. The presence of MPs in food has not yet been evaluated in Latin America. This work focused on evaluating two widely consumed beverages: milk and soft drinks. Furthermore, honey and beer samples were analyzed and compared to findings in the literature. All products were sourced in Ecuador. In order to determine correlations with the intensity of anthropogenic activity, samples of both industrially processed and craft products were studied. For the analysis, an improvement of previous techniques used to determine MPs in honey was applied. This technique uses microfiltration followed by degradation of organic matter with hydrogen peroxide—and finally, continuous rinsing with deionized water. Size ranges were established between 0.8–200 mm. The number of microplastics found was between 10 and 100 MPs/L, with an average of around 40 MPs/L. The sizes of the particles found in the study are in the range of 13.45 and 6742.48 μm for the fibers, and between 2.48 and 247.54 μm for the fragments. From the composition analysis carried out with FTIR, we were able to confirm the presence of 12% of microplastic. The results generally showed a greater presence of MPs compared to those registered in Europe, probably due to processing methods rather than environmental pollution. Regarding composition, the main microplastics found were polyethylene, polypropylene and polyacrylamide.

Low molecular weight aldehydes (LMWAs) formed during the heating of frying media (triglycerides) were adsorbed onto tenax and analyzed by GC-MS after thermal desorption. Six alkanals (C 5 to C 10 ), seven 2-alkenals (C 5 to C 11 ) and 3 alkadienals (C 7 , C 9 and C 10 ) were found in the fumes of canola oil (control), extra virgin olive oil, and refined olive oil, heated at 180 and 240 • C. The emission rates of these aldehydes depended on the heating temperature. Frying in any type of olive oil, independently of its commercial category, will effectively decrease the emission of volatile aldehydes at temperatures below the smoking point. Thus, using the cheaper olive oil for deep-frying purposes will not affect aldehyde emissions. This is important since olive oil is usually used for deep-frying operations while extra virgin olive oil is used as salad dressing in Spain. The mixture of refined olive oil with some virgin olive oil is the most acceptable type of olive oil in non-Mediterranean countries due to its milder flavor. However, if higher temperatures are needed the use of canola oil is more advisable due to its higher smoke point.

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