Mexican researchers sought to evaluate the effects of E171 across a span of conditions in mice, including its influence on behavior, along with the effects on the colon and liver. The research, published in 2020 in the journal Food and Chemical Toxicology, showed that E171 promoted anxiety and induced adenomas, or noncancerous tumors, in the colon. They also found that E171 heightened goblet cells hypertrophy and hyperplasia, which is typically seen in asthma patients and triggered by smoking or external pollutants and toxins. They also noted mucins overexpression in the mice, which can be linked to cancer cell formation. 

TiO2 is a white pigment that is commonly used in the production of paints, plastics, and paper. It is known for its brightness, opacity, and durability, making it an ideal choice for products that require a high level of whiteness and coverage. TiO2 is also used in sunscreen lotions and cosmetics to provide protection against harmful UV rays. In addition, TiO2 is used in the food industry as a food additive to enhance the appearance of products such as candies and confectionery.

Sunscreens and cosmetics containing titanium dioxide are generally considered safe since they are mineral-based products. Mineral products are often recommended for acne-prone and sensitive skin. However, there have been some concerns that titanium dioxide may have a negative impact on health.