Oral intake of added titanium dioxide and its nanofraction from food products, food supplements and toothpaste by the Dutch population

Abstract

Titanium dioxide (TiO 2 ) is commonly applied to enhance the white colour and brightness of food products. TiO 2 is also used as white pigment in other products such as toothpaste. A small fraction of the pigment is known to be present as nanoparticles (NPs). Recent studies with TiO 2 NPs indicate that these particles can have toxic effects. In this paper, we aimed to estimate the oral intake of TiO 2 and its NPs from food, food supplements and toothpaste in the Dutch population aged 2 to over 70 years by combining data on food consumption and supplement intake with concentrations of Ti and TiO 2 NPs in food products and supplements. For children aged 2-6 years, additional intake via ingestion of toothpaste was estimated. The mean longterm intake to TiO 2 ranges from 0.06 mg/kg bw/day in elderly (70+), 0.17 mg/kg bw/day for 7-69-year-old people, to 0.67 mg/kg bw/day in children (2-6 year old). The estimated mean intake of TiO 2 NPs ranges from 0.19 mg/kg bw/day in elderly, 0.55 mg/kg bw/day for 7-69-yearold people, to 2.16 mg/kg bw/day in young children. Ninety-fifth percentile (P95) values are 0.74, 1.61 and 4.16 mg/kg bw/day, respectively. The products contributing most to the TiO 2 intake are toothpaste (in young children only), candy, coffee creamer, fine bakery wares and sauces. In a separate publication, the results are used to evaluate whether the presence of TiO 2 NPs in these products can pose a human health risk.

Risk assessment of titanium dioxide nanoparticles via oral exposure, including toxicokinetic considerations

“…The dietary intake has been estimated by Rompelberg et al (2016) for TiO 2 added during the production process and for TiO 2 NPs therein. The intake was based on intake via food, supplements and toothpaste, according to the Dutch National Food Consumption Survey (DNFCS), and on the average measured total Ti or TiO 2 particle levels in such products.…”

“…Scheme of the risk assessment process. In approach 1, the external human dietary intake (Part 1, described by Rompelberg et al, 2016) and the lowest NOAEL from toxicity studies (Part 3) are compared for the risk characterization (Part 5a). For approach 2, the external intake estimation and the NOAEL are extrapolated to internal doses (Parts 4a and 4b) using the toxicokinetic assessment and a kinetic model as illustrated in Parts 2a and 2b, resulting in a risk characterization based on internal concentrations (Part 5b).…”

“…Organ concentrations of TiO 2 NPs were calculated for the rats and mice in the key studies and for the Dutch consumer using the estimation for oral intake (Rompelberg et al, 2016) and the kinetic model described in Part 2. For each calculation, the kinetic constants of the particle type corresponding best with the tested or consumed particle type were applied, based on expert judgement.…”

“…E-mail: Agnes.Oomen@rivm.nl This is an Open Access article distributed under the terms of the Creative Commons Attribution-NonCommercial-NoDerivatives License (http:// creativecommons.org/licenses/by-nc-nd/4.0/), which permits non-commercial re-use, distribution, and reproduction in any medium, provided the original work is properly cited, and is not altered, transformed, or built upon in any way. Rompelberg et al (2016) estimated the oral intake of total TiO 2 and TiO 2 NPs from food, toothpaste and supplements for the Dutch population. Here, the available information on hazard and toxicokinetics was gathered to assess whether this intake could lead to human health risks.…”

Biokinetics of engineered nano-TiO2 in rats administered by different exposure routes: implications for human health

“…Limited surveys have found that many foods contained 0.01-1 mg TiO 2 /serving (maximum 300 mg TiO 2 /serving) (Lomer et al, 2000;Weir et al, 2012). Estimated human daily consumption based on limited studies varies widely from $0.2 to $200 lg TiO 2 /kg body weight/day, with a maximum of 4 mg/kg body weight per day (Rompelberg et al, 2016;Weir et al, 2012). An adult may consume several milligrams of pigmented TiO 2 in a day.…”