In a 2017 study published in Scientific Reports, researchers exposed rats to human-relevant levels of E171 to examine the effects of intestinal inflammation and carcinogenesis. They saw that “a 100-day E171 treatment promoted colon microinflammation and initiated preneoplastic lesions while also fostering the growth of aberrant crypt foci in a chemically induced carcinogenesis model.” They continued: “Stimulation of immune cells isolated from Peyer’s Patches [which are clusters of lymphoid follicles found in the intestine] showed a decrease in Thelper (Th)-1 IFN-γ secretion, while splenic Th1/Th17 inflammatory responses sharply increased,” researchers wrote. “A 100-day titanium dioxide treatment promoted colon microinflammation and initiated preneoplastic lesions.” The scientists concluded: “These data should be considered for risk assessments of the susceptibility to Th17-driven autoimmune diseases and to colorectal cancer in humans exposed to TiO2 from dietary sources.”
Lithopone B301, Lithopone B311 powder is also widely applied in paints and enamels
We know that there are a lot of suspended organisms and colloidal impurities in natural water. The forms of suspended solids are different. Some large particles of suspended solids can settle under their own gravity. The other is colloidal particles, which is an important reason for the turbidity of water. Colloidal particles can not be removed by natural settlement, because colloidal particles in water are mainly clay with negative electricity The Brownian motion of colloidal particles and the hydration on the surface of colloidal particles make colloidal particles have dispersion stability. Among them, electrostatic repulsion has the greatest influence. If coagulant is added to water, it can provide a large number of positive ions and accelerate the coagulation and precipitation of colloid. Compressing the diffusion layer of micelles makes the potential change into an unstable factor, which is also conducive to the adsorption and condensation of micelles. The water molecules in the hydrated film have fixed contact with the colloidal particles and have high elastic viscosity. It is necessary to overcome the special resistance to expel these water molecules. This resistance hinders the direct contact of the colloidal particles. The existence of some hydrated films depends on the electric double layer state. If coagulant is added to reduce the zeta potential, the hydration may be weakened. The polymer materials formed after coagulant hydrolysis (the polymer materials directly added into water generally have chain structure) play an adsorption bridging role between the colloidal particles. Even if the zeta potential does not decrease or does not decrease much, the colloidal particles can not contact each other and can be adsorbed through the polymer chain Colloidal particles can also form flocs.
Flavoring Agents
Resumen–En este artículo se discute el descubrimiento del litopón fosforescente en dibujos a la acuarela por el artista americano John La Farge, fechados de 1890 a 1905, y la historia del litopón en la industria de los pigmentos a finales del Siglo XIX y principios del Siglo XX. A pesar de tener muchas cualidades deseables para su uso en pintura para acuarela o pinturas al óleo blancas, el desarrollo del litopón como pigmento para artistas fue obstaculizado por su tendencia a oscurecerse con la luz solar. Su disponibilidad para los artistas y su adopción por ellos sigue siendo poco clara, ya que por lo general los catálogos comerciales de los coloristas no eran explícitos al describir si los pigmentos blancos contenían litopón. Además, el litopón se puede confundir con blanco de plomo durante el examen visual, y su fosforescencia de corta duración puede ser fácilmente pasada por alto por el observador desinformado. A la fecha, el litopón fosforescente ha sido documentado solamente en otra obra mas: una acuarela por Van Gogh. Además de la historia de la fabricación del litopón, el artículo detalla el mecanismo para su fosforescencia, y su identificación con la ayuda de espectroscopía de Raman, y de espectrofluorimetría.