A novel and widely accessible HPLC method for determination content of homosalate in sunscreen products on the market

Introduction: Considering that the research has shown that homosalate act as endocrine-active substance, it is very important to develop quick and sensitive method for tracking its concentrations in sunscreen products. The aim of this paper is to develop and validate the method for determining homosalate in sunscreen preparations and controlling the content of the products found on the market of Bosnia and Herzegovina. Methods: A high pressure liquid chromatography (HPLC) method for determination homosalate in sunscreen products has been developed and validated. Samples of six different manufacturers have been analyzed. HPLC method is method of choice for this type of investigation. Results: According to the calibration curve it has been found that the proposed analytical method in a given range of concentration is linear and that the correlation coefficient is R2=0.9998. Accuracy of the method is in range 94.26% -121.53%.The results have shown that the homosalate concentration in the tested samples did not exceed the maximally permissible concentration (10%). In the sample AV50 homosalate was not declared as an active ingredient, but it was identified and quantified at a concentration of 0.143%. Conclusion: Results of investigation of cosmetic products that are widely present on the market show the need of developing a sufficiently sensitive, easily accessible, analytical method for controlling the content of organic UV filters since the exceeding of the maximally permissible concentration can have a harmful effect on people who use these kinds of products. The results show that developed method meets conditions and is suitable for wide application

Study of Homosalate Stability in Chlorinated Water and Identification Chalogenated By-Products by Gas Chromatography-Mass Spectrometry

The increasing use of sun-creams containing organic UV-filters has led to increased concentration of these compounds in aquatic environment. Chlorinated water can convert these chemicals into chlorinated products whose toxic effects are of primary concern. The new compound may be more toxic than the starting primary compound. Many studies have shown that UV filters absorb UV light and decompose under solar irradiation, due to their unstable properties. This may lead to formation of certain by-products with harmful effects. Their decomposition products can cause allergic and toxic reactions to the human skin. This study follows the stability of most commonly used UV filters, homosalate, in conditions that include those existent in swimming pools. Stability of the homosalate in chlorinated water was studied in simulated swimming pool water samples. UV spectroscopy was used to follow the reaction of homosalate in presence of free chlorine. Water samples were filtered, acidified, and extracted by use of solid-phase extraction. Gas chromatography with mass spectrometry was used to identify the major transformation by-products. Under the experimental conditions, homosalate reacted with chlorine following zero order reaction. The chemical transformation of the homosalate in chlorinated water led to formation of chlorinated by-products that was identified as: monochloro-homosalate, dichloro-homosalate and two diastereoisomers monochloro-homosalate

Application of membrane filters in determination of the adsorption of tetracycline hydrochloride on graphene oxide

This paper shows the use of membrane filters in adsorption of solution of tetracycline hydrochloride on graphene materials. The adsorption process was monitored at different wavelengths, different pH values ​​at certain time intervals. The absorbances of the solutions were measured by UV-Vis spectrophotometry at two wavelengths (275 nm and 356 nm), and three pH values (pH 4, pH 7 and pH 10) every 90 minutes for 6 hours of monitoring, with constant stirring in an ultrasonic bath. The results showed decrease in absorbance at both wavelength and in all three pH values which proved the adsorption of tetracycline hydrochloride on GO and rGO. The largest decrease in absorbance was 98.1%. The most suitable pH value for adsorption was pH 4. This paper used a unique approach to filtration through membrane filters, which in the future could lead to the development of membrane filters based on graphene materials

Application of membrane filters in determination of the adsorption of tetracycline hydrochloride on graphene oxide

This paper shows the use of membrane filters in adsorption of solution of tetracycline hydrochloride on graphene materials. The adsorption process was monitored at different wavelengths, different pH values ​​at certain time intervals. The absorbances of the solutions were measured by UV-Vis spectrophotometry at two wavelengths (275 nm and 356 nm), and three pH values (pH 4, pH 7 and pH 10) every 90 minutes for 6 hours of monitoring, with constant stirring in an ultrasonic bath. The results showed decrease in absorbance at both wavelength and in all three pH values which proved the adsorption of tetracycline hydrochloride on GO and rGO. The largest decrease in absorbance was 98.1%. The most suitable pH value for adsorption was pH 4. This paper used a unique approach to filtration through membrane filters, which in the future could lead to the development of membrane filters based on graphene materials

A comprehensive health effects assessment of the use of sanitizers and disinfectants during COVID-19 pandemic: a global survey

COVID-19 has affected all aspects of human life so far. From the outset of the pandemic, preventing the spread of COVID-19 through the observance of health protocols, especially the use of sanitizers and disinfectants was given more attention. Despite the effectiveness of disinfection chemicals in controlling and preventing COVID-19, there are critical concerns about their adverse effects on human health. This study aims to assess the health effects of sanitizers and disinfectants on a global scale. A total of 91,056 participants from 154 countries participated in this cross-sectional study. Information on the use of sanitizers and disinfectants and health was collected using an electronic questionnaire, which was translated into 26 languages via web-based platforms. The findings of this study suggest that detergents, alcohol-based substances, and chlorinated compounds emerged as the most prevalent chemical agents compared to other sanitizers and disinfectants examined. Most frequently reported health issues include skin effects and respiratory effects. The Chi-square test showed a significant association between chlorinated compounds (sodium hypochlorite and per-chlorine) with all possible health effects under investigation (p-value <0.001). Examination of risk factors based on multivariate logistic regression analysis showed that alcohols and alcohols-based materials were associated with skin effects (OR, 1.98; 95%CI, 1.87-2.09), per-chlorine was associated with eye effects (OR, 1.83; 95%CI, 1.74-1.93), and highly likely with itching and throat irritation (OR, 2.00; 95%CI, 1.90-2.11). Furthermore, formaldehyde was associated with a higher prevalence of neurological effects (OR, 2.17; 95%CI, 1.92-2.44). Furthermore, formaldehyde was associated with a higher prevalence of neurological effects (OR, 2.17; 95%CI, 1.92-2.44). The use of sodium hypochlorite and per-chlorine also had a high chance of having respiratory effects. The findings of the current study suggest that health authorities need to implement more awareness programs about the side effects of using sanitizers and disinfectants during viral epidemics especially when they are used or overused