Titanium Dioxide Nanoparticles in Food and Personal Care Products

By A. Weir, Paul Westerhoff, L. Fabricius, Natalie von Goetz. Environmental Science and Technology, 2012

1,978 citations recorded by the source corpus.

Titanium dioxide is a common additive in many food, personal care, and other consumer products used by people, which after use can enter the sewage system, and subsequently enter the environment as treated effluent discharged to surface waters or biosolids applied to agricultural land, incinerated wastes, or landfill solids. This study quantifies the amount of titanium in common food products, derives estimates of human exposure to dietary (nano-) TiO2, and discusses the impact of the nanoscale fraction of TiO2 entering the environment. The foods with the highest content of TiO2 included candies, sweets and chewing gums. Among personal care products, toothpastes and select sunscreens contained 1% to >10% titanium by weight. While some other crèmes contained titanium, despite being colored white, most shampoos, deodorants, and shaving creams contained the lowest levels of titanium (<0.01 μg/mg). For several high-consumption pharmaceuticals, the titanium content ranged from below the instrument detection limit (0.0001 μg Ti/mg) to a high of 0.014 μg Ti/mg. Electron microscopy and stability testing of food-grade TiO2 (E171) suggests that approximately 36% of the particles are less than 100 nm in at least one dimension and that it readily disperses in water as fairly stable colloids. However, filtration of water solubilized consumer products and personal care products indicated that less than 5% of the titanium was able to pass through 0.45 or 0.7 μm pores. Two white paints contained 110 μg Ti/mg while three sealants (i.e., prime coat paint) contained less titanium (25 to 40 μg Ti/mg). This research showed that while many white-colored products contained titanium, it was not a prerequisite. Although several of these product classes contained low amounts of titanium, their widespread use and disposal down the drain and eventually to WWTPs deserves attention. A Monte Carlo human exposure analysis to TiO2 through foods identified children as having the highest exposures because TiO2 content of sweets is higher than other food products, and that a typical exposure for a US adult may be on the order of 1 mg Ti per kilogram body weight per day. Thus, because of the millions of tons of titanium based white pigment used annually, testing should focus on food-grade TiO2 (E171) rather than that adopted in many environmental health and safety tests (i.e., P25), which is used in much lower amounts in products less likely to enter the environment (e.g., catalyst supports, photocatalytic coatings).

Subfields: Materials Chemistry, Public Health, Environmental and Occupational Health

View Paper: https://www.semanticscholar.org/paper/5d7b692d74f6b3d14fced27ac4807acd9f9b1bbd

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Materials Chemistry

1. Kiril D. Hristovski
2. M. A. Kiser
3. A. Ibhadon
4. Paul Westerhoff
5. P. Fitzpatrick
6. Arturo Keller

Citations in the corpus

• Heterogeneous Photocatalysis: Recent Advances and Applications (2013, background): “The widespread application of nanoparticle TiO2 should, in theory, have beneficial impacts on the health of the general public and thus on the quality of life [3].”
• Nanomaterial Removal and Transformation During Biological Wastewater Treatment (2013, positive): “First, dispersed ENMs are incorporated into food products to improve texture, preservation, or nutrition (Abbas et al ., 2009; Bouwmeester et al ., 2009; Arora and Padua, 2010; Magnuson et al ., 2011; Weir et al ., 2012).”
• The current application of nanotechnology in food and agriculture (2018, positive): “For example, food-grade TiO 2 NPs now have been found up to approximately 40% in the nanometer range [18,19].”
• Green Synthesis of Metallic Nanoparticles: Applications and Limitations (2021, background): “Food Production TiO2 Antimicrobial, coating in packaging material, detection of volatile compounds [198]”
• Effect of nanoparticles on crops and soil microbial communities (2018, background): “Production estimate for TiO2 NPs increased from 2000 t in 2005 to 5000 t in 2010 (Weir et al. 2012).”