An investigation into the present levels of contamination in children's toys and jewelry in different countries: a systematic review

Contamination by heavy metals and toxic elements in children's toys and jewelry is an ongoing challenge in different countries. These contaminants can enter the children's body via oral, dermal, and respiratory routes, leading to adverse health effects. This study aimed to investigate the present levels of contamination in children's toys and jewelry in 15 countries, including UK, Saudi Arabia, Cambodia, China, Kosovo, Nigeria, North American, Kazakhstan, UAE, Pakistan, Iraq, Israel, West Bank/Palestine, Czech Republic, and Turkey. In this review, the legislation and recommendation of the United States (U.S.), the Bureau of Indian Standards (BIS), Turkish Standards Institute (TSE), Canada, and the European Union (E.U.) on toxic elements in toys and jewelry are introduced. Plastic or metallic toys and children's jewelry still have the most severe toxic elements pollution and the existence of lead (Pb), nickel (Ni), cadmium (Cd), arsenic (As), mercury (Hg), chromium (Cr), copper (Cu), selenium (Se), barium (Ba), Zinc (Zn), cobalt (Co), manganese (Mn), bisphenol A, phthalates, parabens, azo dyes, and flame retardants has been regarded as an ongoing challenge in these articles. Finally, this review offers benchmarking of the concentrations of toxic elements in all types of children's toys and jewelry in different nations.

Influence of ozone supply mode and aeration on photocatalytic ozonation of organic pollutants in wastewater using TiO2 and ZnO nanoparticles

Photocatalytic ozonation, which combines the effects of lighting and ozonation, has been shown to enhance the decolorization and degradation of organic pollutants in wastewater. Dye solutions with concentrations of 10 ppm for both methylene blue and methyl orange dyes were used. The influence of ozoneation on the performance of photocatalytic activity of TiO2 and ZnO nanoparticles for the removal of organic dyes from aqueous solutions was investigated. To evaluate their efficacy for the removal of methylene blue and methyl orange dyes from aqueous solutions, the photocatalysts were exposed to UV light for 90 min, with ozone supplied either intermittently or continuously by an SDBD cold plasma reactor. The photocatalysts utilized in this study were characterized using SEM and XRD techniques. The degree of color degradation was determined using UV-Vis spectroscopy. The results demonstrate that TiO2 and ZnO nanoparticles exhibit different degrees of photocatalytic activity for the two dyes. The addition of ozone was found to enhance both the color degradation and mineralization rates of the pollutants, with intermittent ozonation proving more effective than continuous ozonation. The most significant color degradation results were obtained using TiO2 nanoparticles with intermittent ozonation for methylene blue dye (97 %) and ZnO nanoparticles with intermittent ozonation for methyl orange dye (40 %). Overall, this study provides evidence that photocatalytic ozonation represents a promising technique for water treatment.

An investigation into the association between suicide mortality rate and lithium levels in potable water: a review study

This study aimed to investigate the association between lithium levels in potable water and suicide mortality rates in the total inhabitants. We systematically searched Embase, PubMed/MEDLINE, Scopus, PubMed Central (PMC), Google Scholar databases, as well as medRxiv using the following keywords: drinking water, lithium, standardized mortality ratio (SMR), tap water, suicide, and ground water. Pearson regression analysis was used to test an association between variables with 95% confidence interval (CI). A value of P < 0.05 was considered significant. A total of 16 eligible articles were identified. Lithium concentrations in drinking water range from 0.4 to 32.9 μg/l. Average rates of suicide mortality (per 100 000 capita) range between 0.790 (±0.198) and 123 (±50). About 16 original studies confirmed the inverse relationship between lithium concentrations in potable water and suicide mortality rates (R = -0.576; R2 = 0.3323; 95% CI, -0.820 to -0.325; β = -0.3.2; P = 0.019). High lithium concentrations in potable water were associated with decreased suicide rates. We concluded that lithium concentration in potable water was inversely associated with suicide mortality rates among a total population. However, further research is required to clarify the relationship between lithium concentrations in drinking water and suicide rate.