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Millions of tons of titanium dioxide are produced globally. It is used to give whiteness and brightness to products and also helps them resist discoloration. Titanium dioxide also reflects ultraviolet (UV) light, which is why it’s often used as an ingredient in sunscreens.
Which food is it found in?
It is found in candies, sweets and chewing gum which are considered to contain the highest levels of titanium dioxide. It is also found in white powdered doughnuts, candies and gums with white icing and even bread, mayonnaise, yogurt and other dairy products.
It is also present in paint and is added to cosmetics, toothpastes, pharmaceuticals, paper and food.
Dunkin Donuts allegedly removed ‘nano’ Titanium dioxide from powdered sugar donuts. In response to pressure from the advocacy group As You Sow, Dunkin’ Brands has announced that it will be removing “nano” titanium dioxide from Dunkin’ Donuts’ powdered sugar donuts. ‘As You Sow’ claims there are safety concerns around the use of the material, while Dunkin’ Brands cites concerns over investor confidence.
Why is it considered dangerous?
Although Titanium dioxide is considered safe, but as more products are using titanium dioxide nanoparticles, that is changing everything.
Nanoparticles are ultramicroscopic in size, making them able to readily penetrate your skin and travel to underlying blood vessels and your bloodstream. Evidence suggests that some nanoparticles may induce toxic effects in your brain and cause nerve damage, and some may also be carcinogenic.
The International Agency for Research on Cancer (IARC) classifies titanium dioxide as a Group 2B carcinogen, which means it’s “possibly carcinogenic to humans.” This was based on an animal study showing inhaling high concentrations of titanium dioxide dust may lead to lung cancer.
Harmful effects of Titanium Dioxide
Toxicological studies have shown that Titanium Dioxide nanoparticles predominantly cause adverse effects via induction of oxidative stress resulting in cell damage, genotoxicity, inflammation, immune response etc.
The damage caused strongly depends on physical and chemical characteristics of Titanium Dioxide nanoparticles, which govern their bioavailability and reactivity.
Based on the experimental evidence from animal inhalation studies TiO2 nanoparticles are classified as “possible carcinogenic to humans” by the International Agency for Research on Cancer and as an occupational carcinogen by the National Institute for Occupational Safety and Health.
Sources:
http://minerals.usgs.gov/minerals/pubs/commodity/titanium/mcs-2014-titan.pdf
http://particleandfibretoxicology.biomedcentral.com/articles/10.1186/1743-8977-10-15
http://theconversation.com/dunkin-donuts-ditches-titanium-dioxide-but-is-it-actually-harmful-38627