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Electrolysis was the first acid-free method in the era of nontoxic etching, which is simple and efficient. However, in its traditional form involves the use of specific salts, according to the metal used for etching. This requirement, together with the need for a power source increases the cost of the process. In this paper a simple and inexpensive solutions to those obstacles is described. For the former, a 25% solution of table salt is proposed as universal electrolyte for any of the metals used in etching. Then, for the second problem, the response is the use the power supply of personal computers discarded. Both options make the process of electro-etching in one of the cheapest and efficient methods of etching, La electrólisis fue el primer método libre de ácido en la era de grabado no tóxico; el cual es muy simple y eficiente. Sin embargo, en su forma tradicional se emplean sales específicas de acuerdo con el metal usado para el grabado. Este requisito, junto con la necesidad de una fuente de poder aumenta el coste del proceso. En este artículo se describe una solución sencilla y económica para esos obstáculos. Para el primero, una solución al 25% de sal de mesa, se propone como electrolito universal para cualquiera de los metales utilizados en el grabado. Luego, para el segundo problema, la respuesta es el uso de las fuentes de energía de las computadoras personales desechadas. Ambas opciones convierten el proceso de grabado electrolítico en uno de los métodos más baratos y eficientes de grabado

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.

The world of printmaking changed in the 1990s with a series of rediscoveries that started with electrolytic etching, followed by the applications of mordents. These methodologies have relegated the use of nitric acid from the printmaking workshop, together with other potentially toxic substances, that include colophony resin, asphalt and petroleum-derived solvents. the dream of the modern printmaker is a technique that is safe and free of any toxic substances; however, as always, in any place, there are risks for our health, and having avoided toxic substances from the etching, it could be argued that electrolysis also produces dangerous gases. Then, the question arises: How safe is electrolytic etching? In this context, the main fear is the hydrogen gas liberated during electrolytic etching when table salt is used as a universal electrolyte. This gas is highly flammable. Nevertheless, its associated risk depends on its concentration in an enclosed environment, such as a workshop. For this reason, the aim of this paper was quantification of the amount of hydrogen generated during 15 minutes period of electrolysis, using aluminum plates of 5x8 cm, this metal was selected for the experiments because is the most reactive from the other metals used in printmaking. The average amount of hydrogen produced in 12 experiments was 120ml. Under the experimental conditions evaluated, to get a hazardous concentration of hydrogen in a hermetically sealed enclosure, of 4x4x4 meters, it would be necessary to etch out one kilogram of aluminum, equivalent to 84 etchings in plates of 240x150x1,6mm, whose average weight decreased 12g after the process. Fortunately, the accumulation of hydrogen in a standard workshop can be easily avoided with an open window or better with two open opposing windows. In conclusion the electrolytic etching using table salt is a safe method to etching aluminum and any other metal, such as copper, iron, zinc, and steel., El mundo del grabado cambió en los años noventa con una serie de redescubrimientos, que comenzaron con el grabado electrolítico, seguido por las aplicaciones de los mordentes salinos. Esas metodologías han relegado el uso del ácido nítrico del taller de grabado, junto con otra sustancia potencialmente tóxica, que incluye resina de colofonia, asfalto y muchos solventes del petróleo. El sueño del grabador moderno es una técnica segura y libre de cualquier sustancia tóxica. Sin embargo, siempre, en cualquier lugar hay riesgos para nuestra salud y habiendo evitado las sustancias tóxicas en el grabado, se podría argumentar que la electrólisis también produce gases peligrosos. Entonces, surge la pregunta: ¿Qué tan seguro es el grabado electrolítico? En este contexto, el principal temor es el hidrógeno liberado durante el grabado electrolítico cuando se utiliza sal de mesa como un electrolito universal. Este gas es altamente inflamable, sin embargo, su riesgo asociado depende de su concentración en un entorno cerrado, tal como un taller. Por este motivo, el objetivo de este trabajo fue la cuantificación de la cantidad de hidrógeno generado durante 15 minutos de electrólisis, utilizando placas de aluminio de 5x8 cm, este metal fue seleccionado para los experimentos porque es el más reactivo de entre los otros metales utilizados en grabado. La cantidad media de hidrógeno producida en 12 experimentos fue de 120 ml. Bajo las condiciones experimentales evaluadas, para obtener una concentración peligrosa de hidrógeno en un recinto herméticamente cerrado, de 4x4x4 metros, sería necesario consumir un kilogramo de aluminio, equivalente a 84 grabados en láminas de 240x150x1,6mm, cuyo peso promedio disminuyera 12g después del proceso. Afortunadamente, la acumulación de hidrógeno en todo caso se puede evitar fácilmente con una ventana abierta o, mejor aún con dos ventanas en lados opuestos del taller. En conclusión, el grabado electrolítico usando sal de mesa es un método seguro para

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.

The use of ultrasound (US) in the preparation of pharmaceutical grade (PG) sodium chloride by the sampling of final product from a vacuum evaporator during the process of obtaining the “Extra” class table salt at the crystallization stage of the sodium chloride has been investigated. The US had been used: 1) for the content control of the base matter – sodium chloride in the stock – natural brine (sonoluminescent spectroscopy method). It is necessary to create the appropriate crystallization conditions by the control of the vacuum evaporator parameters – temperature and pressure; 2) at the crystallization stage of the sodium chloride to reduce the co-crystallization between the sodium chloride and the sulfate ions. It has been shown that the use of US allows reducing the sulfate ions content in the final product and getting sodium chloride PG satisfying the requirements of pharmacopoeia standard (PS) 42-2572-88.

The use of ultrasound (US) in the preparation of pharmaceutical grade (PG) sodium chloride by the sampling of final product from a vacuum evaporator during the process of obtaining the “Extra” class table salt at the crystallization stage of the sodium chloride has been investigated. The US had been used: 1) for the content control of the base matter – sodium chloride in the stock – natural brine (sonoluminescent spectroscopy method). It is necessary to create the appropriate crystallization conditions by the control of the vacuum evaporator parameters – temperature and pressure; 2) at the crystallization stage of the sodium chloride to reduce the co-crystallization between the sodium chloride and the sulfate ions. It has been shown that the use of US allows reducing the sulfate ions content in the final product and getting sodium chloride PG satisfying the requirements of pharmacopoeia standard (PS) 42-2572-88.

In the era of non-toxic etching there are two methodological ways: electrolysis and mordents. One obstacle faced is the achievement of specific substances to each metal. However is possible to use table salt as universal electrolyte for any metal and saline sulfate to etch copper, aluminum, iron and zinc. The reduction of the specter of substances employed simplified the methods, En la era del grabado no tóxico hay dos vertientes metodológicas, la electrólisis y mordentes. Un obstáculo enfrentado es la consecución de sustancias específicas para cada metal. No obstante, es posible utilizar la sal de cocina como electrolito universal para cualquier metal y el sulfato salino para grabar cobre, aluminio, hierro y cinc. La reducción del espectro de sustancias empleado simplifica los métodos

Dietary sodium, the major source being salt, is associated with hypertension. Australian adults consume more than the recommended amount of salt and approximately 15% of dietary sodium comes from salt added at the table and during cooking. Objective: To determine the frequency of and the demographic characteristics associated with discretionary salt use. Design: A cross sectional survey conducted in shopping centres within Metropolitan Melbourne. Participants completed a questionnaire assessing discretionary salt use and attitudes to salt intake. Outcomes: Four hundred and seventy four surveys were collected (65% female, 77% Caucasian, 64% holding a university qualification). Eighty nine percent of respondents were classified as salt users and 11% as non-salt users. Of the salt users 52% reported that they always or sometimes add salt during cooking and at the table. Those of Asian descent and younger respondents aged 18-24 years were more likely to be salt users (chi2=12.3, df=2, p<0.001; chi2=19.2, df=5, p<0.01). Conclusion: Discretionary salt use remains high. To successfully reduce population dietary salt intake public health campaigns are urgently required and need to include consumer advice to reduce discretionary salt use, whilst reducing the salt added to processed foods. Such campaigns should include younger age groups and should be appropriate for all ethnic backgrounds to raise the awareness of the risks of a high salt diet on health.

The samples of table salt bought in Belgrade supermarkets are analyzed in this paper. The method of indirect iodometry was used in the process of the analysis, and received results were converted into the content of KI in mg/kg of salt. Beside the content of KI, the content of NaCl was also determined, counted to dry meter and water content, and received results were compared with the requests determined by Regulations of Table Salt Quality Meant for Human Diet and by manufacturers' declaration. Received results show that the volumetric method of indirect iodometry, applied in this analysis, is very reliable for determination of potassium iodine in table salt, because of its high precision and reproducibility of the analysis results. All received results show that the samples of table salt which can be bought in supermarkets are according to the demands given by Regulations. Only one sample (evaporated salt) has significantly less mass of KI than it is determined by Regulations, but also by manufacturer's declaration. Measured humidity in the samples of table salt received from sea salt (sample 1) is higher than humidity in the samples received from rock salt as the result of magnesium presence in sea salt, which is hygroscopic material. Although samples 5 and 6 also originate from sea salt, their smaller humidity is the result of additional heating and salt processing., U radu su ispitivani uzorci kuhinjske soli koji se mogu nabaviti u beogradskim prodavnicama. U radu je primenjena metoda indirektne jodimetrije, a dobijeni rezultati su preračunavani na sadržaj KI u mg/kg soli. Osim sadržaja KI, određivan je i sadržaj NaCl, računato na suvu materiju i sadržaj vode, a dobijeni rezultati upoređeni su za zahtevima koji su predviđeni Pravilnikom o kvalitetu kuhinjske soli predviđenim za ljudsku ishranu i proizvođačkom deklaracijom. Dobijeni rezultati su pokazali da je volumetrijska metoda indirektne jodimetrije, primenjena u ovom radu, veoma pouzdana za određivanje kalijum-jodida u kuhinjskoj soli, usled velike preciznosti i reproduktivnosti rezultata ispitivanja. Svi dobijeni rezultati pokazali su da uzorci kuhinjske soli koji se mogu nabaviti u trgovini odgovaraju zahtevima Pravilnika, osim jednog uzorka (varena so) koji je sadržao znatno manju masu KI nego što je predviđeno Pravilnikom, ali i proizvođačkom deklaracijom. Izmerena vlažnost u uzorcima kuhinjske soli dobijene iz morske vode (uzorak 1.) veća je od vlažnosti u uzorcima dobijenim iz kamene soli kao posledica prisustva magnezijuma u morskoj vodi, koji je higroskopni materijal. Iako su i uzorci 5. i 6. poreklom iz morske vode, njihova mala vlažnost posledica je dodatnog zagrevanja i dorade soli.