To be added to food, this additive must achieve 99% purity. However, this leaves room for small amounts of potential contaminants like lead, arsenic, or mercury (1Trusted Source).
2. Relative density: 4.136 to 4.39 g/mL.
Some websites maintain titanium dioxide is inferior to zinc oxide, another mineral sunscreen ingredient whose core characteristics are similar to those of titanium dioxide. The reality is that titanium dioxide is a great broad-spectrum SPF ingredient and is widely used in all manner of sun-protection products. What gets confusing for some consumers is trying to decipher research that ranks sunscreen ingredients by a UV spectrum graph. By most standards, broad-spectrum coverage for sunscreen ingredients is defined as one that surpasses 360 nanometers (abbreviated as “nm” - how the sun’s rays are measured). Titanium dioxide exceeds this range of protection, but depending on whose research you read, it either performs as well as or slightly below zinc oxide.