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.
EFSA has updated its safety assessment of the food additive titanium dioxide (E 171), following a request by the European Commission in March 2020.
Of the products that include the additive in their labels, Thea Bourianne, senior manager at data consultant Label Insights, told Food Navigator USA in May 2021 that more than 11,000 products in the company's database of U.S. food and beverage products listed titanium dioxide as an ingredient. Non-chocolate candy led those numbers at 32%. Cupcakes and snack cakes made up 14%, followed by cookies at 8%, coated pretzels and trail mix at 7%, baking decorations at 6%, gum and mints at 4% and ice cream at 2%.