Titanium Dioxide Nanoparticles in Food and Personal Care Products

Abstract

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).

Nanoparticle accumulation and transcytosis in brain endothelial cell layers

“…TiO 2 is one of most frequently used materials in commercial products, e.g., cosmetics and dental care, 66 and concerns regarding the effects of TiO 2 nanoparticles on human health, including neurological damage, 67,68 have been raised. However, the fate of TiO 2 nanoparticles upon exposure to the human BBB has not been clearly defined to date.…”

The impact of TiO2 nanoparticles on uptake and toxicity of benzo(a)pyrene in the blue mussel (Mytilus edulis)

“…Due to their photocatalytic properties TiO2NP are among the most used and produced ENPs, with applications in building materials, self-cleaning paints and self-sterilizing surfaces, as food additive and in cosmetics (Gottschalk et al, 2009;Quagliarini et al, 2012;Robichaud et al, 2009;Weir et al, 2012). TiO2NPs have been reported to be released from consumer products such as self-cleaning façade paints, and despite a high removal rate in waste water treatment plants TiO2NP have been detected in waste water treatment plant effluents, indicating environmental exposure (Kiser et al, 2009;Neal et al, 2011;Westerhoff et al, 2011).…”

Nanomaterialien in Lebensmitteln – toxikologische Eigenschaften und Risikobewertung

“…Aber auch bei der Lebensmittelherstellung können nanoskalige Metallpartikel, etwa durch Maschinenabrieb, entstehen und in den Lebensmitteln verbleiben [5]. Auch einige Lebensmittelzusatzstoffe können Anteile von Partikeln im Nanomaßstab enthalten: beispielsweise Titandioxid (E171) und Siliziumdioxid (E551) [6][7][8]. Zur Exposition liegen nur für wenige Partikelspezies Daten vor.…”