Use of Food Additive Titanium Dioxide (E171) before the Introduction of Regulatory Restrictions Due to Concern for Genotoxicity

Abstract

Food-grade titanium dioxide (TiO2; E171) is a coloring food additive. In May 2021, a scientific opinion was published by the European Food Safety Authority concluding that TiO2 can no longer be considered as a safe food additive. Our aim was to investigate the trends in the use of TiO2 in the food supply. A case study was conducted in Slovenia using two nationally representative cross-sectional datasets of branded foods. Analysis was performed on N = 12,644 foods (6012 and 6632 in 2017 and 2020, respectively) from 15 food subcategories where TiO2 was found as a food additive. A significant decrease was observed in the use of TiO2 (3.6% vs. 1.8%; p < 0.01). TiO2 was most often used in the chewing gum category (36.3%) in 2017, and chocolate and sweets category (45.9%) in 2020. Meanwhile, in 2017, the largest share of TiO2-containing foods was observed in the chewing gum category, namely, 70.3%, and these products presented over 85% of the market share. In 2020, only 24.6% of chewing gums contained TiO2, which accounted for only 3% of the market share. In conclusion, we showed an overall decrease in TiO2 use, even though it has not yet been officially removed from the list of authorized food additives.

Full text

Foods 2021, 10, 1910. https://doi.org/10.3390/foods10081910 www.mdpi.com/journal/foods
Communication
Use of Food Additive Titanium Dioxide (E171) before the
Introduction of Regulatory Restrictions Due to Concern for
Genotoxicity
Urška Blaznik 1, Sanja Krušič 2, Maša Hribar 2, Anita Kušar 2, Katja Žmitek 2,3 and Igor Pravst 2,3,4,*
1 National Institute of Public Health, Trubarjeva 2, SI-1000 Ljubljana, Slovenia; urska.blaznik@nijz.si
2 Nutrition Institute, Tržaška Cesta 40, SI-1000 Ljubljana, Slovenia; sanja.krusic@nutris.org (S.K.);
masa.hribar@nutris.org (M.H.); anita.kusar@nutris.org (A.K.); katja.zmitek@vist.si (K.Ž.)
3 VIST—Higher School of Applied Sciences, Gerbičeva Cesta 51A, SI-1000 Ljubljana, Slovenia
4 Biotechnical Faculty, University of Ljubljana, Jamnikarjeva 101, SI-1000 Ljubljana, Slovenia
* Correspondence: igor.pravst@nutris.org; Tel.: +38-659-068-871
Abstract: Food-grade titanium dioxide (TiO2; E171) is a coloring food additive. In May 2021, a sci-
entific opinion was published by the European Food Safety Authority concluding that TiO2 can no
longer be considered as a safe food additive. Our aim was to investigate the trends in the use of TiO2
in the food supply. A case study was conducted in Slovenia using two nationally representative
cross-sectional datasets of branded foods. Analysis was performed on N = 12,644 foods (6012 and
6632 in 2017 and 2020, respectively) from 15 food subcategories where TiO2 was found as a food
additive. A significant decrease was observed in the use of TiO2 (3.6% vs. 1.8%; p < 0.01). TiO2 was
most often used in the chewing gum category (36.3%) in 2017, and chocolate and sweets category
(45.9%) in 2020. Meanwhile, in 2017, the largest share of TiO2-containing foods was observed in the
chewing gum category, namely, 70.3%, and these products presented over 85% of the market share.
In 2020, only 24.6% of chewing gums contained TiO2, which accounted for only 3% of the market
share. In conclusion, we showed an overall decrease in TiO2 use, even though it has not yet been
officially removed from the list of authorized food additives.
Keywords: titanium dioxide; E171; food supply; nanoparticles; safety; Europe; Slovenia
1. Introduction
Titanium dioxide (TiO2) is a transition metal oxide with application as a pigment or
photocatalyst [1]. As a white pigment it has been added to a variety of food products,
including bakery products, sauces, cheeses, edible ices and sweets. In addition to food,
titanium dioxide is also used in medicinal products as an excipient, and in personal care
products as a pigment and thickener [2,3], and can also be used as an UV filter in mineral
sunscreen products [4,5].
TiO2 was first approved for use in food in 1966 by the US Food and Drug Admin-
istration (FDA), with the stipulation that its content must not exceed 1% of the food weight
[6]. On the basis of the Codex Alimentarius of the Food and Agriculture Organiza-
tion/World Health Organization (FAO/WHO) [1] safety evaluation, TiO2 has been author-
ized as a food additive by the European Union (EU) with code E171 since 1969 [7]. Due to
the presence of a fraction of nanoparticles, it falls under the scope of the EFSA Guidance
on nanotechnology as “a material that is not engineered as nanomaterial but contains a
fraction of particles, less than 50% in the number–size distribution, with one or more ex-
ternal dimensions in the size range 1–100 nm” [8]. E171 as a food additive consist of ap-
proximately 40% of TiO2 nanosized particles (<100 nm) and 60% of TiO2 microsized par-
ticles (>100 nm) [2,9,10]. As it was permitted for use in the EU before 20 January 2009, it
Citation: Blaznik, U.; Krušič, S.;
Hribar, M.; Kušar, A.; Žmitek, K.;
Pravst, I. Use of Food Additive
Titanium Dioxide (E171) before the
Introduction of Regulatory
Restrictions Due to Concern for
Genotoxicity. Foods 2021, 10, 1910.
https://doi.org/10.3390/
foods10081910
Academic Editors: Isabel María
Moreno Navarro and Juan D.
Bautista Palomas
Received: 14 June 2021
Accepted: 13 August 2021
Published: 17 August 2021
Publisher’s Note: MDPI stays neu-
tral with regard to jurisdictional
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tional affiliations.
Copyright: © 2021 by the authors. Li-
censee MDPI, Basel, Switzerland.
This article is an open access article
distributed under the terms and con-
ditions of the Creative Commons At-
tribution (CC BY) license (http://crea-
tivecommons.org/licenses/by/4.0/).

Foods 2021, 10, 1910 2 of 11
belongs to the group of food additives that are subject to a safety re-evaluation by the
European Food Safety Authority (EFSA), according to Commission Regulation (EU) No.
257/2010, and in line with the provision of Regulation (EC) No. 1333/2008 [11]. Therefore,
the safety of TiO2 as a food additive was re-evaluated by the EFSA Panel on Food Addi-
tives and Nutrient Sources added to Food (ANS) [12] in 2016, on the basis of which the
EFSA concluded that TiO2 did not raise concerns with respect to genotoxicity and carcino-
genicity. Genotoxicity refers to the ability of a chemical substance to damage the genetic
material of cells, which may lead to carcinogenic effects [13]. EFSA also recommended
that additional studies be conducted to fill the gaps in possible effects on the reproductive
system, which could lead to an established Acceptable Daily Intake (ADI) for TiO2. There-
fore, in January 2017, the European Commission (EC) issued an open call for additional
data for TiO2, including reproductive toxicity data. Several studies investigated the tox-
icity of dietary TiO2 [10,14–25], raising some concerns regarding its potential tumor-pro-
moting activity. In 2018, the outcome of four specific studies [10,14,20,23] was included in
a scientific evaluation to determine the need to re-open the conclusion of the EFSA’s opin-
ion from 2016. However, the decision was taken in 2018 that the re-opening of this issue
was not needed [26]. In April 2019, the French Agency for Food, Environmental and Oc-
cupational Health and Safety (ANSES) delivered a scientific opinion, based on 25 studies
published between 2017 and 2019 [27], on the exposure to nanoparticles of TiO2, and high-
lighted that the previous EFSA assessment did not consider all available data. In response
to this opinion [28], the EFSA noted that ANSES reiterated previously identified concerns
and data gaps, and did not present findings that changed the Authority’s previous con-
clusions on the safety of TiO2. Furthermore, the Office for Risk Assessment and Research
of the Netherlands Food and Consumer Product Safety Authority (NVWA) delivered an
opinion on possible health effects of TiO2 in 2019 [29], highlighting the possible immune
and reproductive toxicological effects of TiO2. While further activities were underway to
obtain new data, the French Government followed the precautionary principle, based on
the opinion of the ANSES in 2019 [27], and decided to ban TiO2 in food products starting
on 1 January 2020. Just a few days after this decision was announced, a joint letter to the
EC [30] was published to EC, with civil society organizations requesting to remove TiO2
from the EU list of permitted food additives. Following the request of the EC in March
2020, the EFSA started an additional safety evaluation of this additive. An in-depth safety
assessment report for the TiO2 was published on 6 May 2021 [31]. The EFSA panel con-
cluded that with consideration of the available evidence, a concern for genotoxicity could
not be excluded and, therefore, TiO2 could no longer be considered as a safe food additive.
As mentioned, several studies have addressed the question of toxicity of E171. Stud-
ies on rats and mice have shown that nanoparticles can pass through the intestinal barrier,
accumulate in the intestine and cause preneoplastic lesions [14,32], promote anxiety, in-
crease the number of adenomas in the colon, induce hypertrophy and hyperplasia in gob-
let cells [33] and disrupt gut microbiota composition and function [34–38]. Accumulation
and toxic effects have also been found in plants [39,40]. However, health aspects of E171
oral intake by consumers in a real exposure environment still need to be confirmed by
further research.
Food additives are an important part of processed foods. Consumers have expressed
concern for some time about their possible adverse health effects [41] and would like to
be better informed about their potential health implications [42,43]. EU Member States,
and the EC as risk managers, request the EFSA to provide independent scientific advice,
which informs European food policy makers. In the next step, the EFSA’s scientific advice
on TiO2 will be used to support further regulatory procedures and decisions. The most
realistic outcome is that the use of TiO2 as a food additive will not be approved in the EU
in the near future.
The objective of this study was to evaluate the prevalence and changes in the use of
TiO2 as a food additive in the food supply since 2017, when the EC issued an open call for
additional toxicity data for TiO2. The Slovenian food supply was selected for a case study,

Foods 2021, 10, 1910 3 of 11
using nationally representative cross-sectional data on the composition of prepacked
foods in 2017 and 2020 collected within the national “Nutrition and Public Health” re-
search program and the “Food Nutrition Security Cloud” project (FNS-Cloud; www.fns-
cloud.eu, accessed: 15 August 2021).
2. Materials and Methods
2.1. Data Collection and Categorization
The study was conducted on a sample of prepacked foods available in Slovenia, EU.
The food supply sample was collected in 2017 and 2020 in major retail shops representing
the majority of the food market, and was part of the Composition and Labelling Information
System (CLAS, Nutrition Institute, Ljubljana, Slovenia) [44]. In both years, data collection
was done in retail shops of Mercator, Spar, Tuš, Lidl, Hofer, while in 2020 we also included
retailer Eurospin. The dataset was prepared by the extraction of food labelling information
from photographs of all branded foods available in selected food stores at the time of collec-
tion. Data were collected with the aim of monitoring the nutritional composition of pro-
cessed foods in the food supply [45], with the adaptation that we also collected ingredient
lists. The detailed methodology of the data collection is described elsewhere [46,47].
Foods were classified into food categories according to Global Food Monitoring
Group (GFMG) recommendations [45], with minor modifications [46,47]. Without food
supplements, food additives sold to consumers in food stores and food that did not fit into
any of the GFMG food groups, our dataset contained 49,919 prepacked food items; 23,690
and 26,229 from 2017 and 2020 monitoring, respectively. For 10,034 products (42%) in the
2017 dataset, there was a matching product with same International/European Article Num-
ber (EAN) barcode in the 2020 dataset. We identified all foods in this dataset, where the
ingredient list text contained the terms “TiO2”, “E171” and/or “titanium (di)oxide”.
Food (sub)categories that contained foods with TiO2 as a food additive at least in one
sampled year and were further investigated in this study are as follows: biscuits; cakes,
muffins and pastry; canned fish with vegetables; chewing gum; chocolate and sweets; cor-
dials; desserts; flavored yogurt; ice cream and edible ices; jelly; processed fish products;
side dishes; soup; spreads and processed cheese; and sugar. Our total study sample, there-
fore, included between 12.664 and 6.012 foods for 2017, of which 215 contained TiO2
(3.6%), and 6.632 foods for 2020, of which 122 (1.8%) contained TiO2.
2.2. Data Processing and Statistical Analyses
Food composition data were processed using Microsoft SQL Server Management
Studio 13.0, Microsoft Analysis Services Client Tools 13.0, Microsoft Data Access Compo-
nents (MDAC) 10.0, Microsoft Excel 2019 (Microsoft, Redmond, Washington, DC, USA)
and the Composition and Labelling Information System (CLAS) (Nutrition Institute,
Ljubljana, Slovenia). Statistical analyses were performed using Microsoft Excel 2019 (Mi-
crosoft, Redmond, Washington, DC, USA).
For statistical evaluation, we calculated proportions of TiO2-containing foods in dif-
ferent food (sub)categories. Additionally, we calculated the within-category proportion of
foods containing TiO2, which was corrected with product market shares using the previ-
ously described sale-weighting approach [47]. In the investigated food categories, market
share data were available for 59.8% (N = 3597) and 54.2% of foods (N = 3597) for 2017 and
2020, respectively. Sale-weighted proportions of TiO2-containing foods were calculated
for each (sub)category separately, using the EAN barcode as a unique product identifier,
with consideration of product packaging quantity and number of sold products in a 12-
month period (based on nationwide sales data provided by food retailers). Food subcate-
gories with less than four TiO2-containing foods were excluded from this analysis.
Descriptive analysis was used for proportions of food that contained TiO2, and the
95% confidence interval (95% CI) was calculated employing the Wilson score interval [48].
A two-tailed z-test was used to identify differences in the use of TiO2 between 2017 and

Foods 2021, 10, 1910 4 of 11
2020. The level of significance was set at p < 0.05. The following subcategories were ex-
cluded from this part of the analysis due to their low sample size of foods containing TiO2:
processed fish products; canned fish with vegetable; sugar; ice cream and edible ices; des-
serts; flavored yogurt; cordials; soup; biscuits; side dishes and spreads and processed
cheese.
3. Results and Discussion
The study was conducted on a sample of 6012 foods and beverages in 2017, and 6632
foods and beverages in 2020. Within the 15 selected food subcategories, 13 categories con-
tained TiO2 in 2017 (215 products), and 10 categories in 2020 (122 products). In 2017, foods
containing the highest amount of TiO2 were distributed in the chewing gum category,
accounting for more than a third (36.3%) of the total amount of TiO2-containing foods
(Figure 1). The second third was represented by chocolates and sweets (32.6%), followed
by cakes, muffins and pastry (11.6%), jelly (8.4%) and processed fish products (2.3%). In
2020, almost half of TiO2 was distributed in the chocolate and sweets category (45.9%) and
one third in the chewing gum category (27.9%), followed by cakes, muffins and pastry
(9.0%), jelly (5.7%) and processed fish products (4.9%) (Figure 1). The remaining categories
(each with less than a 3% share) represented 9% and 7% of TiO2-containing foods in 2017
and 2020, respectively (Figure 1, “Other”).
Figure 1. Distribution of foods containing TiO2 per food (sub)category in 2017 versus 2020.
To provide insights into food reformulation practices, we also compared the compo-
sition of foods, which were found in both 2017 and 2020 dataset. Food matching using
EAN barcodes resulted in 10,034 foods available in both datasets. Altogether, 88 of these
products contained TiO2 in the 2017 sample, while in 2020 the use of TiO2 was retained in
49 products (55.7%). This indicates that food reformulation (removal of TiO2) was ob-
served in 44.3% (N = 39) products.
Furthermore, we calculated per-category proportions of TiO2-containing foods in the
food supply for both 2017 and 2020 (Table 1). For each year, we calculated the (non-
weighted) proportion as a percentage of TiO2-containing foods of all available foods in the
category. To gain an insight into the availability of such foods with a consideration of
market share, we further employed the sale-weighting approach using nationwide 12-
month sales data, provided by the largest food retailers in Slovenia. Such an approach
provided information on whether TiO2 was used in market-leading brands or mostly in
niche products. It should be noted that sales data were available for most, but not all foods
2017 2020

Foods 2021, 10, 1910 5 of 11
in our study sample (see Section 2.1 for details). Missing data mostly reflect availability in
discounter retailers.
Per-category, nonweighted proportions of TiO2-containing foods represented up to
70.3% in 2017 (Table 1). In 2017, the largest share of TiO2-containing foods was represented
by chewing gum, comprising more than two third of the sample (70.3%), followed by jelly
(9.7%) and processed fish products (7.0%) (Table 1). Chewing gum was also the highest
ranked category (24.6%) in 2020, followed by processed fish products (6.9%) and jelly
(4.4%).
In 2017, the sale-weighted proportion of TiO2-containing chewing gums was higher
than the nonweighted proportion (85.5% vs. 70.3%), showing that this food additive was
present in major brands. The situation changed considerably in 2020, when the sale-
weighted proportion was much lower (3.1% vs. 24.6%). This indicates that a decrease in
the use of TiO2 was even more pronounced in the best-selling products. We also compared
the composition of the chewing gums, which contained TiO2 in 2017, and were still mar-
keted in 2020. Out of 44 such products, 25 (56.8%) no longer contained TiO2 in 2020. This
indicates that TiO2 dropped not only because of the arrival of new (TiO2-free) products
and removal of older (TiO2-containing) products from the market, but also because of the
reformulation of the existing products. However, the differences between sale-weighted
and nonweighted proportions in other food categories were expressed to a much lower
extent. Beside chewing gums, food subcategories with the highest sale-weighted propor-
tions of foods with TiO2 were jelly (14.8%) and processed fish products (19.3%) in 2017.
Considerably high sale-weighted proportions were also observed in these two categories
in 2020 (20.2% and 19.0%, respectively).
The overall comparison of the 2017 and 2020 data showed a significant (p < 0.01) de-
crease in the use of TiO2 as a food additive from 2017 to 2020. Across the 15 observed food
subcategories, 3.6% foods contained TiO2 in 2017, and 1.8% in 2020. This change could be
attributed to the availability of new evidence on the potential health risks of TiO2, and by
concerns raised by national health authority agencies [27,29]. As health concerns were also
raised by EFSA [31], it is expected that responsible food producers will remove it from
their products, despite the fact that it has not yet been officially restricted from the EU
food supply. A statistically significant decrease in the use of TiO2 was also observed in
specific food categories where TiO2 was a relevant additive in 2017. Sale-weighted pro-
portions showed a similar trend, with the exception of the abovementioned processed fish
products and jelly.

Foods 2021, 10, 1910 6 of 11
Table 1. (Sub)category proportions of foods containing TiO2 (E171) as food additive in the food supply for 2017 and 2020 (Slovenia).
Food Category
2017 2020 z-Test Statistic for
Proportions
Total N
Added
TiO2
N
% (95% CI) Sale-Weighted
Proportion (%) Total N
Added
TiO2
N
% (95% CI) Sale-Weighted
Proportion (%)
Proportion
Change
(95% CI)
p-Value
Chewing gum 111 78 70.3 (61.8–78.8)
85.5 138 34 24.6 (17.4–31.8) 3.1 45.6 (34.5–56.8) <0.01
Jelly 185 18 9.7 (5.5–14.0) 14.8 159 7 4.4 (1.2–7.6) 20.2 5.3 (0.0–10.6) 0.03
Processed fish products 71 5 7.0 (1.1–13.0) 19.3 87 6 6.9 (1.6–12.2) 19.0 0.1 (−7.8–8.1) ns
Cakes, muffins and pastry 569 25 4.4 (2.7–6.1) 3.0 639 11 1.7 (0.7–2.7) 1.1 2.7 (0.7–4.6) <0.01
Chocolate and sweets 1917 70 3.7 (2.9–4.5) 2.8 2173 56 2.6 (1.9–3.2) 1.1 1.1 (0.0–2.1) 0.02
Canned fish with vegetable 60 1 1.7 (0.3–8.9) * 60 0 ns
Sugar 127 2 1.6 (0.4–5.6) * 108 0 ns
Ice cream and edible ices 431 6 1.4 (0.3–2.5) 1.6 586 3 0.5 (0.0–1.1) * 0.9 (−0.4–2.1) ns
Desserts 207 2 1.0 (0.4–2.3) * 298 0 ns
Flavored yogurt 419 3 0.7 (0.2–2.1) * 386 0 ns
Cordials 179 1 0.6 (0.1–3.1) * 190 0 ns
Soup 264 1 0.4 (0.1–2.1) * 257 1 0.4 (0.1–2.2) * 0.0 (−1.1–1.1) ns
Biscuits 1035 3 0.3 (0.1–0.9) * 1122 2 0.2 (0.1–0.6) * 0.1 (−0.2–0.5) ns
Side dishes 199 0 224 1 0.5 (0.1–2.5) * ns
Spreads and processed cheese 238 0 205 1 0.5 (0.1–2.7) * ns
Total 6012 215 3.6 (3.1–4.0) na 6632 122 1.8 (1.5–2.2) na 1.8 (1.1–2.3) <0.01
Notes: Data presented for food categories with at least one product with TiO2 in either the 2017 or 2020 dataset. 95% CI: 95% confidence interval; N—number of all products; ns—not
significant; na—not applicable; *—low sample size (sale-weighted proportions not calculated for subsamples with N < 4).

Foods 2021, 10, 1910 7 of 11
To our knowledge, this is the first repeated cross-sectional study on the use of TiO2
in the food supply in which trends in the use of TiO2 in prepacked foods were investigated
with consideration of market share data. Such methodology makes the study results par-
ticularly relevant for the assessment of public health risks. While this makes comparisons
with other studies difficult, relevant comparisons can be performed without consideration
of sale-weighting. Mintel’s Global New Products Database (GNPD) [49], which contains
data of newly launched foods in different countries (but not Slovenia), was used in the
recent safety assessment of TiO2 by EFSA [31]. For a more relevant comparison, we com-
bined several of Mintel’s food subcategories [50]. The highest proportion of TiO2-contain-
ing foods was observed in chewing gums (39%), followed by pastilles, gums, jellies and
chews (10%), cakes, pastries and desserts (4%); and chocolate and sweets (3%) [31]. The
Mintel database cannot be considered as cross-sectional, as it only contains data on newly
launched products on the market (and not the overall situation in the food supply, where
some market-leading brands have a long history of availability). Nevertheless, it should
be mentioned that a decreasing trend in the use of TiO2 in newly launched foods was also
observed. Data are also available for the US, where TiO2 was most commonly used in
nonchocolate candy (32%), followed by cupcakes and snack cakes (14%), cookies (8%),
coated pretzels and trail mix (7%), baking decorations (6%), gum and mints (4%) and ice
cream (2%). However, it was assumed that many other foods contain TiO2, because in the
US market TiO2 can be considered as an exempt color that does not require explicit decla-
ration on the ingredient statement [51].
Exposure to TiO2 largely depends on an individual’s dietary habits. Since TiO2 is
mainly present in processed foods such as chewing gum, cakes, pastry and other sweets,
children and young people are more likely to be more exposed to higher TiO2 intake. For
the United Stated and United Kingdom population it has been calculated that children
potentially consumed two to four times as much TiO2 per kg body weight as an adult [2].
Similar studies revealing that children consume higher amount of TiO2 were observed
across Europe [52] in the German and [53] Dutch population [21,54], and among Chinese
young people [55].
Given scrutiny from regulatory bodies, the food industry has been working on TiO2
alternatives for some years. Reformulation initiatives were also stimulated by various
nongovernmental active groups. In the US, for example, the As You Sow group put pres-
sure on the Dunkin’ brand, which then withdrew the use of TiO2 from their sugar pow-
dered donuts [56]. However, replacing TiO2 across all applications is technologically very
challenging, as TiO2 is not only an excellent whitening pigment but also very cost effective
[51]. However, rice starches now offer clean label solutions that can help with reducing
the chipping and cracking of coatings [51]. Avalanche, starch and mineral based white
opacifier are the most common replacements for TiO2 in food applications [57].
The strength of the present study is in the use of two large nationally representative
cross-sectional food composition datasets in combination with market shares. While such
an approach was used in the past for the assessment of public health risks related to spe-
cific nutrients, such as salt [58] and sugar [47], we showed that it can also be employed for
food additives. The limitation of the study is that the used dataset did not contain all avail-
able foods, and that sales data were not available for the whole dataset. However, we
should mention that data collection included all major retailers with a nationwide net-
work of food stores, and that sales data were available from retailers who are responsible
for over 50% of the food market. Another limitation is that the data on the use of TiO2
were extracted from food labels, and not determined in a laboratory. However, regula-
tions require the labeling of functional additives, and the laboratory analysis of thousands
of foods is not a feasible option in food supply studies. We should also note that our study
did not investigate certain groups of foods in which a higher use of coloring agents could
be expected, such as food supplements and food additive products (i.e., foods sold directly
to consumers which are intended for coloring), which are also available to consumers in
food stores.

Foods 2021, 10, 1910 8 of 11
4. Conclusions
According to the results of our study, the availability of prepackaged food products
in Slovenia has undergone several improvements regarding the use of TiO2 in certain food
categories. This is particularly notable in the category of chewing gum, where a reformu-
lation trend was also observed. In recent years, we have witnessed an increased regulatory
scrutiny of TiO2 as a food additive. In other studies, this was reflected in a decline in new
launches of foods containing TiO2, while this cross-sectional study also confirmed such an
observation in a whole supply of processed foods in Slovenia. We observed that in the
past, the category with the most common use of TiO2 was chewing gum. In 2017, approx-
imately 70% of chewing gums contained TiO2, and these products presented over 85% of
the market share (by weight). However, the situation changed drastically; in 2020, approx-
imately 25% of chewing gums contained TiO2, accounting for only 3% of the market share.
The other two food categories with a high use of TiO2 were jelly and processed fish prod-
ucts, while in other food categories, less than 3% of products contained TiO2. Considering
the EFSA’s 2021 announcement of TiO2 no longer being safe to use, a further decrease in
the use of this additive is expected despite the fact that it has not yet been officially re-
moved from the list of authorized food additives in the EU. Specific food categories were
identified (i.e., chocolate and sweets), in which product reformulation is needed, and of-
ficial controls by authorities will be most relevant.
Author Contributions: Conceptualization, I.P.; data collection, M.H., S.K. and U.B.; methodology,
I.P. and U.B.; formal analysis, S.K.; writing—original draft preparation, I.P., S.K. and U.B.; manu-
script writing—review and editing, all authors; manuscript review, A.K. and K.Ž. All authors have
read and agreed to the published version of the manuscript.
Funding: Data collection for this study was supported by the national research program “Nutrition
and Public Health” (P3-0395, funded by the Slovenian Research Agency), and the Food Nutrition
Security Cloud project (FNS-Cloud), which received funding from the European Union’s Horizon
2020 Research and Innovation program (H2020-EU.3.2.2.3.—a sustainable and competitive agri-
food industry) under grant agreement No. 863059. Information and views in this report do not nec-
essarily reflect the official opinion or position of the European Union. Neither the European Union
institutions and bodies nor any person acting on their behalf may be held responsible for the use of
the information contained herein.
Institutional Review Board Statement: Not applicable.
Informed Consent Statement: Not applicable.
Data Availability Statement: The data presented in this study are available on request from the
corresponding author.
Acknowledgments: The authors would like to thank the retailers for granting access to their stores
to collect data for the study. We also acknowledge collaborating researchers at the Nutrition Insti-
tute and students from the Biotechnical Faculty (University of Ljubljana) and BIC (Ljubljana) for
their help in the data collection.
Conflicts of Interest: The authors declare no conflict of interest. The funders had no role in the
design of the study; in the collection, analyses or interpretation of data; in the writing of the manu-
script; or in the decision to publish the results. Igor Pravst has led and participated in various other
research projects in the fields of nutrition, public health and food technology, which were
(co)funded by the Slovenian Research Agency; the Ministry of Health of the Republic of Slovenia;
the Ministry of Agriculture, Forestry and Food of the Republic of Slovenia; and in the case of specific
applied research projects, also by food businesses.

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