Since titanium dioxide barely penetrates the human skin barrier. it is usually harmless to humans. However. when inhaled in high concentrations. especially as nanoparticles commonly found in e-cigarettes. it can pose a potential health risk. While titanium dioxide is widely used in a variety of consumer products. including sunscreens and food coloring. prolonged exposure can cause respiratory problems.

Silica resin is a highly porous, granular form of silicon dioxide commonly used in chromatography for the separation and purification of biomolecules. It's derived from silica gel, a form of silicon dioxide synthesized from sodium silicate. The unique characteristic of silica resin lies in its ability to be modified on its surface, allowing for the attachment of various functional groups. These modifications enable the selective interaction with different molecules based on size, charge, or hydrophobicity, making it an indispensable tool in biochemical and analytical applications. Its stability across a wide range of pH levels and its high surface area for adsorption make it ideal for precise separations. However, silica resin can be prone to degradation under extreme pH conditions, which limits its use in some scenarios. In research and pharmaceutical industries, silica resin plays a crucial role in purifying DNA, proteins, and other vital substances.

India ink, traditionally made from a mixture of carbon black and a binding agent (often shellac), does not typically contain soy. The carbon black is produced by burning bones, tar, pitch, and other substances. Modern formulations might vary, including synthetic binders or additives, but soy-based ingredients are uncommon in traditional and most commercial India ink products. However, in the art materials market, there is a growing trend towards more environmentally friendly and non-toxic products, so it's essential to check the specific product ingredients for any soy content if this is a concern. Manufacturers can alter formulations, so for those with allergies or seeking soy-free products, consulting the label or manufacturer directly is always recommended.