report international phd-trip 2011
TRANSCRIPT
Report International PhD-trip 2011
Division of Toxicology
1
2
Contents
Summary ................................................................................................................................................. 4
Givaudan, Kemptthal (CH) ....................................................................................................................... 5
EAWAG, Dübendorf (CH) ....................................................................................................................... 11
Nestlé Research Center, Lausanne (CH) ................................................................................................ 15
European Food Safety Authority (EFSA), Parma (I) ............................................................................... 19
Final remarks ......................................................................................................................................... 22
Staff at the Division of Toxicology ......................................................................................................... 23
Picture impression during social activities ............................................................................................ 24
Sponsors ................................................................................................................................................ 26
3
4
Summary The Fugu’s move beyond boarders to broaden their horizon
For the first time the PhD students of the Division of Toxicology (the Fugu’s) from Wageningen
University have organized an international study tour. Switzerland and Italy were chosen as countries
to visit, since they host numerous prestigious companies and institutes of interest in the field of
toxicology. The trip started on Sunday morning the 19th
of June when 11 PhD students and 1 co-
worker of the Division of Toxicology gathered at Schiphol to catch a flight to Zurich. In Zurich 2 other
PhD students joined the group. During the first two days of the trip, two institutes in the area of
Zurich, Givaudan and EAWAG, were visited. Both days included mini-symposia and laboratory tours.
On Monday afternoon there was time for a social activity: a tour through the beautiful city center of
Zurich. On Tuesday afternoon the group travelled by train to Lausanne. The next day a symposia at
the Nestlé Research Center was held, where PhD students were given the opportunity to present
their PhD projects and also scientific staff from Nestlé presented their work. Early Thursday morning
the group travelled by train via Milano to Parma for the last visit on the program, European Food
Safety Authority (EFSA). On Thursday afternoon there was time for a cultural visit through the city
center of Parma and a visit was made to the Duomo and Battistero. The day was nicely ended by a
dinner at restaurant San Barnaba with the head of the Division of Toxicology Prof. dr. ir. I.M.C.M
Rietjens. On Friday morning the group visited EFSA, and traveled back via Milano Linate to The
Netherlands in the evening.
5
Givaudan, Kemptthal (CH)
Givaudan is the global leader in the fragrance and flavour industry, offering its products to global,
regional and local food, beverage, consumer goods and fragrance companies. The flavour division
has four business units of which beverages (36%) and savoury (snacks, soups etc.) (35%) cover over
70% of the business. Further business units are sweet goods (16%) and dairy products (13%).
The fragrance division has three business units of which consumer products (cosmetics, household
products, etc.) cover two-thirds of the overall business (67%). But also fine fragrances (perfumes)
(20%) and fragrance ingredients (13%) are important business units.
The Headquarter of Givaudan is located in Vernier, Switzerland, where Givaudan was founded in
1895. Over the globe Givaudan has a presence in all major markets and a network of 82 sites in
mature and developing regions.
Time Title Presentation and Speaker
9.30
9.35
10.20
11.00
11.20
11.35
11.55
12.15
13.30
13.45
14.30
15.30
15.40
Arrival of PhDs students at Givaudan
Welcome at Givaudan, flavor and fragrance industry by Werner Morf (GIV)
Regulatory and toxicology work in flavor department by Michaela Heinemann (GIV)
Coffee Break
Presentation of the Division of Toxicology WUR, by Jochem Louisse (WUR)
PhD project presentation, by Alicia Paini (WUR)
PhD project presentation, by Jochem Louisse (WUR)
Lunch
PhD project presentation, by Linda Gijsbers (WUR)
Regulatory and toxicology work in fragrance department by Graham Ellis (GIV)
Product development, flavour creation & application by Werner Morf (GIV)
a short view in the laboratories and pilot plant
End Symposium
Departure of students
6
Minutes by: Nynke Evers and Agata Walczak
On Monday we went to visit fragrance and flavour company
Givaudan in Kemptthal. As soon as we got out of the train we
were welcomed by Michaela Heinemann, our hostess for the
day. When we walked onto the property ground we knew we
were in the right place, it smelled like soup and a little later like
liquorice.
The first presentation of the day was by Werner Morf. He made it clear that you cannot avoid this
industry: the Givaudan products are in shampoo, shower gel, tooth paste, breakfast, orange juice,
candy, and so on.
In 1900 Givaudan started as Chemical Plant Flora AG. In 1917 Maggi AG Kemptthal buys Flora AG, in
2000 they continued as a spin-off from Roche, and there were lots of take-overs and merges (over
20, among others with Nestlé) in between but that all went a bit fast.
By now their global research & development on flavours is worth 2,2 billion CHF and on fragrances 2
billion CHF. Together with the market share of 25%, it keeps Givaudan in the top position in its field,
and leaves its 9 major competitors far behind. The market growth of Givaudan is assessed at 2-3%.
Most of the sales (64%) are connected with mature markets, while only 36% regard the developing
ones. The majority of the sales (39%) fall into the area of Europe, Africa and Middle East. Fragrances
research is situated in Deubendorf (CH), flavours research in Cincinatti (OH, USA). The flavours
Givaudan produces are for savory 35%, beverages 35%, confectionary 18%, and dairy 12%. The
fragrances are intended for consumer products (65%), fine fragrances (20%) and ingredients (15%).
One product is a blend of about 30 to 150 raw materials. The products have a form of liquid, powder
or granulate. 95% of their products are created exclusively to one customer. Although their market
size is already about 25%, they see future perspectives in the Middle east or China.
When they create a flavour, they try to make it as close to nature as possible, so they aim at
simplicity, however the matrix usually needs to be very complex. However, when they create a
fragrance, they can have high level of creativity, while the matrix is very simple: ethanol. Still the
fragrances and flavours share 25% of identical raw materials, product development processes,
production & IT systems, and research - and instrumental analytics. However, Givaudan has a
reputation to keep up. 80% of their projects are customer projects, driven by market, which aim at
creating typical products, asked for by customers. The other 20% are called “pro-active” projects and
they are marketing driven, aiming at producing completely new products, demonstrating creativity.
Therefore, they are sometimes also very creative with flavours, like the production of ice cream with
herbs & spices. In nature a strawberry consists of more than 500 smelling compounds, Givaudan can
imitate one with about 25-50 compounds. Interestingly, these 500 substances form only about 0,001-
0,005% of the whole mass of the strawberry.
We also got a little lesson in perfume architecture. The top notes are citrus, green notes, and spicy
(highly volatile); the middle notes are floral and fruity; and the bottom notes are woody, musk, iris,
and violet. A flavourist or perfumer can identify 1200 raw materials and this is the palette for
perfumes. The human brain can detect 15000 different smells. Givaudan tries to launch 3 new
7
molecules per year (although they start with more, a lot is lost in the pipeline). Beforehand the smell
of such a molecule is not predictable and it needs to be checked.
Their toxicological research is mostly about the in vitro toxicological evaluation of fragrance
materials, and the development of alternatives to animal testing. At the moment all the tests still
have to be done on animals. Every new molecule needs to be tested before applying at the market.
However, only the separate compounds are checked, but not the whole fragrance composition. Only
fragrance molecules are tested, not flavours. It is important to test a molecule for allergic reactions
and its biodegradation capabilities. They also do bioanalysis of sweat.
The next presentation was by Michaela Heinemann. She talked about the Product Safety and
Regulatory Affairs group at Givaudan, and especially about the Scientific affairs group. They are
responsible for the registration of new materials in all markets where Givaudan intends to introduce
the ingredient, for the safety of globally used flavour ingredients and for advocacy work in
international and national associations of the flavour industry. For each part of the world there are
different rules and regulations they have to follow and different toxicity data they need for
registration at a lot of different organizations (like EFSA for EU and FEMA for US). It takes a very long
time to register a new food flavor- 3 months to prepare the special form and then waiting for the
decision for some months. However, this is necessary to ensure the safety for consumers, prevent
deception of consumers and ensure proper information for the consumer.
After this presentation we had a little break. They took good care of us; there were drinks and
brownies.
Then Jochem Louisse continued with his talk on research at the
division of Toxicology in Wageningen. He talked about the main
topics at the department, being physiologically based kinetic
and dynamic (PBK/PBD) modeling which would result in a better
model for low dose extrapolation, at differential doses, target
organs and individuals; matrix effect for better risk assessment;
functional food ingredients; alternatives for animal testing; and
nanotoxicology.
After this introduction Alicia Paini took the floor. Her talk was
about the establishment and validation of an in vitro PBBD
model for Estragole. Estragole is carcinogenic in rats, but there
is daily human exposure. She found that DNA adduct formation
increases linear with dose decrease in time. The model results
were compared with rat in vivo data. The model for human
exposure is below endogenous background so there is no
reason for concern.
Alicia also presented the work of Wasma Al-Husainy on matrix mediated effects. Wasma is also
working on estragole. She found that there is SULT inhibition by nevadensin on estragole, and that at
1% bioavailability there is already 80% availability. Nevadensin, quercitin, apigenin, and kaempferol
in the matrix are all SULT inhibitors. When they are present in equal percentages, they give
additional effects. After this presentation there was an interesting discussion on whether there is
SULT activity in plants and if that could be defense mechanism.
8
Givaudan treated us on a very nice hot lunch in their canteen, after which we quickly continued with
the last part of the presentation session.
The opener after lunch was Graham Ellis with a presentation on global fragrance toxicology.
Exposure to fragrances is 90% dermal, 10% inhalation, and a negligible amount oral. From research
they know that the consumer is concerned about the influence of fragrances on health and
environment. This concern gains more and more attention, which is demonstrated by increasing
number of adequate organizations and associations, as well as protests carried out worldwide
(mainly to minimize animal testing). One ingredient often used in fragrances is limonene. This is a
natural constituent of citrus fruits, however, Givaudan is obliged to label it as an allergen; even
though cutting an orange gives the same exposure as 35 sprays of cologne type fragrance (5% alc.) or
140 sprays of a modern women’s fragrance (12% alc.).
Furthermore they are involved in client support, global chemical regulation compliance,
development of in vitro alternative methods, QSAR use and development, and environmental
toxicology. They look for alternatives to animal testing and for that tests are primarily run with cell
cultures. The outcomes of these tests must give the same results as animal tests, in order to be
accepted by the regulatory bodies. The used in vitro tests are: skin sensitisation assays
(KeratinoSens), bioaccumulation assay and mammalian metabolism simulation. The KeratinoSens
test is based on luciferase induction and ap. 85,7% of its results predict the in vivo situation.
Nowadays toxicologists go further and want to identify not only skin irritants but also skin sensitizers
for testing new cosmetics. The plan is to completely resign of animal studies in EU after 2013. They
also use a test called Peptide Reactivity Assay, based on LC-MS, which measures simultaneously
protein depletion, adduct formation and protein oxidation. They for example analyse sensitizing
molecules with LC/MS, and check if it is possible to remove sensitizing properties by altering the
chemical structure of the compound. Givaudan combines assays and look at aquatic
bioaccumulation. The in vivo studies are made on rainbow trout as a model organism. They for
example use trout liver S9 fractions to assess metabolic potential. On QSAR and computer modelling
they mainly work with Times, Catalogic, Episuite, Multicase, and Aecd toolbox. By using these tests,
they can assess the metabolism of a compound, based on its disappearance from the environment.
Times is used to predict skin sensitisation and mutagenicity. However, it is still difficult to distinguish
between strong and weak skin sensitizers.
From the discussion we had with Graham Ellis it turned out that endocrine disruption issue is not
considered nowadays when assessing toxicity of fragrance products. The reason is that there is no
9
good validated method to do so. However, it has been shown that musk has some effects on the
endocrine functions.
Now Jochem Louisse took the floor for the second time to tell about his own project. He works on
the prediction of developmental toxicology with the embryonic stem cell test. Therefore he uses
glycol ethers with toxic metabolites. He explained that he first determined the in vitro effect
concentration in the EST (cytotox), developed the PBK model describing in vivo kinetics, evaluated
the PBK model, extrapolated the in vitro concentrations to in vivo doses, and finally could predict
BMDL10 values for risk assessment (in human).
Also Linda Gijsbers had a very interesting talk on her project entitled: An assay toolbox for benificial
health effects of functional foods. She explained that the goal of the project is to develop and
validate bioassays to measure health effects of foods. PPAR gamma has insulin sensitizing effects,
anti-inflammatory effects, anti-cancer effects, and is therefore a very interesting target. BDS
developed a reporter gene assay for PPAR gamma activity and Linda explained how it worked and
how she validated it.
Finally, Werner Morf concluded the presentation session. He gave one last short general
presentation, saying that senses is not only flavour or taste. Like fragrances, also flavours are built
up: the top notes are aroma; the middle notes are body and complexity (spices and yeast); the
bottom notes consist of taste and mouthfeel; and the carrier is the mouthfeel (salt, acid, umami).
The blending of spices is flavour creation. Over 6000 raw materials are used in production, over 3000
ingredients are used for creation. A human check (sniffing) is very important (batch comparison).
There are namely a lot of factors that can influence flavour and fragrance stability, like oxygen, light,
pH, heat, humidity, and so on. The shelf life of fragrances is ap. 1-3 years starting from the day of
production. Foods contain a plethora of individual flavour molecules, e.g. banana: 225, strawberry:
400, freshly brewed coffee: 700, or grilled steak: 2000. It is possible to reproduce most of the fruit
smells with 15 ingredients. Still most (60%) ingredients used in fragrance production are supplied by
nature, as it is cheaper and faster. “Nose”, a talented and qualified person testing fragrances, is still
very important in this business, because human nose is ap. 100 times more sensitive than a
computer.
After the presentations, we got a little tour around a part of the building. We encountered among
others a sensory room, a kitchen with chemicals, a fragrance lab, a high smell chemicals storage, and
a GC/MS. During the tour more smells were encountered, like stew and fried chicken.
10
It was a very interesting and enjoyable day!
11
EAWAG, Dübendorf (CH) EAWAG is an interdisciplinary research team keenly interested in understanding the effects that
chemicals have on the aquatic environment. Their specific strength is to link exposure to chemicals
with effect assessment from the sub-cellular level to resulting organism, population and community
level consequences. This extrapolation is based on theoretical knowledge and empirical evidence in
chemical speciation and interaction with biological target sites. Their focus is on a mechanistic
understanding of the effects of chemicals, alone or in combination with other stressors, on aquatic
organisms as a basis for knowledge-based environmental risk assessment and risk minimization.
Time Title Presentation and Speaker
08.30 Welcome with short introduction of the symposium, by Danielle Madureira and Flavio
Piccapietra
08.40 Presentation of EAWAG (Utox), by Prof. Dr. Kristin Schirmer
09.05 Presentation of WUR, the Division of Toxicology, by Jochem Louisse
09.30 PhD project presentation, by Katrin Tanneberger (EAWAG)
09.45 PhD project presentation, by Nynke Evers (WUR)
10.00 PhD project presentation, by Merel van der Ploeg (WUR)
10.15 Break
10.35 PhD project presentation, by Sourav Bhattacharjee (WUR)
10.50 PhD project presentation, by Lena Roehder (EAWAG)
11.05 PhD project presentation, by Theodora Stewart (EAWAG)
11.20 PhD project presentation, by Smitha Pillaj (EAWAG)
11.35 Lunch and Poster session
11.50 PhD project presentation, by Si Wang (WUR)
13.00 PhD project presentation, by Julita Stadnicka (EAWAG)
13.15 Conclusion, by Daniella Madureira and Flavio Piccapietra
13.30 Building Tour
14.15 Lab Tour
14.45 Departure of students
12
Minutes by: Elise Hoek and Mohammed Ariful Islam (Arif)
Although we started the day quite early (at 7.15), we arrived at the institute a bit late as we walked
from the station to the EAWAG building with all our luggage. On behalf of the local organizing
committee, Danielle and Flavio (PhD-students from EAWAG) were waiting for us at the entrance of
the building.
After a very short welcoming speech of Danielle and Flavio, the formal program started by the
presentation of Prof. Kristin Schirmer. In her presentation, Prof. Kristin introduced their research
group (Utox) in short. The main aim of Utox is to understand mechanisms of action of chemicals and
nanoparticles on the aquatic environment. There are 40 people working in 4 sub-groups.
The 4 key research themes, each described briefly with some examples, are:
• Nano ecotoxicology
• Single and multiple stressors
• Linking cause and effect across biological levels
• Advancement of models and procedures for risk assessment.
After this presentation of Prof. Schirmer we had a short coffee break.
To introduce the division of Toxicology (WUR), Jochem Louisse gave a nice presentation mentioning
the main research interest of our department, the Toxicology Division Wageningen University (WUR).
13
After that Dr. Katrin Tanneberger (Post doc. fellow) presented her in vitro fish cell (RT gill-Wi) model
as an alternative model for measuring aquatic ecotoxicity, to replace fish acute toxicity tests. From
the WUR group, Laura asked about the availability of the tested compound in the environment as
they tested different type of chemicals. In reply, Dr. Katrin said that they use a specific data base to
select the chemicals.
Then Nynke Evers presented her PhD project regarding ERα and ERβ related cell proliferation and
apoptosis. People asked questions about the difference between ERα and ERβ; if one is better than
the other. A second question was about the compounds Nynke uses for Merck. And a general
question: How bad are phytochemicals actually?
After a coffee break Merel van der Ploeg told about her PhD project. Few questions were raised
regarding the bioavailability of C60 and the dose used for the experiment. Three more questions
asked were about the concentrations present in the environment, biodegradation and sources of
exposure.
As the EAWAG group was very much interested to know about our nanotoxicology research, Laura
presented slides of Sourav’s project (as Sourav could not join the trip). The presentation was about
the cytotoxicity of NPs on the basis of size and surface charge.
Then Lena Roehder presented her project regarding CeO2 NPs. She also introduced the other people
working with different NPs in their research group (UTOX). As CeO2 is not stable in water and get fully
sediment within 24 hrs, a question was asked by Laura about the environmental relevancy to work
with these types of NPs. Moreover, Niek suggested using river water.
After these first presentations during the morning, a very nice lunch was served and we could discuss
and mingle. Moreover, several posters were presented of studies performed at EAWAG as well as at
our department.
Theodora Stewart presented her PhD project entitled: ‘The role of the extracellular matrix in lead
accumulation and toxicity in freshwater periphyton’. The main objectives are to examine the
influence of the extracellular matrix on the distribution and bioavailability of lead to periphytic
organisms, and to assess the toxic effects of lead on periphython.
After the presentation of Theodora Stewart, Dr. Smitha Pillai presented her project entitled:
Phenotype anchoring of silver exposed algae. She has looked to the effect of silver on different
metabolic pathways: effect on growth, increased amount of lipid bodies and size, and oxidative
stress. She has performed microarray analysis and physiological parameters.
14
Then Si Wang presented his PhD project about Toxicogenomics-based in vitro alternatives for the
uterotrophic assay. One question was asked by Smitha: Can you select the genes by yourself on these
microarrays?
Julita Stadnicka presented her PhD project entitled: ‘Predicting toxicity to fish based on in vitro data
via a two-step model’. Her project is part of the CREAM project. She wants to predict toxicity of
chemicals to fish. Therefor she wants to combine toxicokinetic and toxicodynamic models to predict
internal concentrations in fish, and tot link from sub-organ scale to organism scale effects.
The program ended at 3.30 with an interesting tour by visiting different laboratories and the
environmental friendly institutional building.
We left EAWAG around 15.00 hrs. After taking some group pictures in front of the main building and
travelled to Lausanne by train.
15
Nestlé Research Center, Lausanne (CH)
Nestlé Science and Research, encompassing the Nestlé Research Center and its extensive network of
external alliances, is the core of fundamental scientific research in Nestlé. With a staff of 700 people,
including over 3000 scientist from 50 nationalities, our broad range of scientific competencies are
central to fulfilling Nestlé’s vision of Good Food, Good life.
Nestlé research is very active in consumer health benefit areas, employing multidisciplinary
approaches to science and research. Integrating diverse scientific disciplines and expertise ranging
from nutrition, life science, food technology, and consumer science, Nestlé strives to bring practical
nutrition solutions to consumers.
Time Title Presentation and Speaker
8.45 Arrival of PhDs students at NRC
9.00 Start symposium with welcome from B. Schilter (P.J. Van Bladeren) (NRC)
9.05 Risk Assessment and Research at Nestlé, by Benoit Schilter (NRC)
9.35 Presentation of the Division of Toxicology- WUR, by Jochem Louisse (WUR)
9.50 PhD project presentation, by Agata Walczak (WUR)
10.20 Coffee Break
10.50 Toxicogenomics to Approach Risk-Benefit of Phytochemicals, by James Holzwarth (NRC)
11.30 PhD project presentation, by Suzanne van den Berg (WUR)
11.45 PhD project presentation, by Barae Jomaa (WUR)
12.00 PhD project presentation, by Niek van der Pas (WUR)
12.15 Application of In Silico Methods in Food Chemical Risk Assessment, by Elena Lo Piparo (NRC)
13.00 Lunch
14.15 PhD project presentation, by Mohammed Ariful (Arif) Islam (WUR)
14.30 Science in the Management of Crisis: Example Melamine, by P. P. Zbinden (NRC)
15.15 Coffee Break
15.45 PhD project presentation, by Reiko Kiwamoto (WUR)
16.00 PhD project presentation, by Elise Hoek (WUR)
16.15 Final words end of symposium
16.30 Departure of students from NRC
16
Minutes by: Linda Gijsbers and Barae Jomaa
The symposium was opened by Alicia Paini, PhD Student at WUR and Nestlé Research Centre.
The first presentation of the day was given by Benoit Schilter, Head of Chemical Food Safety Group,.
Nestlé is the world’s largest food company. The presentation focussed on definition of safety (CODEX
2001): “the reasonable certainty of no harm to the consumers under the conditions of its intended
use”. Followed by explanation of the tasks involved inside the company to obtain a safe product,
which include risk assessment, risk management and risk communication (risk analysis paradigm).
The chemical food safety group is involved in food safety risk assessment, early warning in
emergency issues, involved in almost all stages of product design, guideline development,
experimental methods development, performance of safety studies, as well as representing Nestlé in
scientific expert groups and competence development and training.
After the presentation of Benoit Schilter, Jochem Louisse gave an overview of the research at the
Toxicology division.
Jochems presentation was followed by a presentation of
Agata Walczak entitled ‘In vitro assays for the hazard
identification of silver nanoparticles’. In her presentation
Agata mentioned among others that AgNP are used for
their antimicrobial properties in the food sector. The aim
of her project is to make in vitro models for identification
of AgNP toxicity without the use of animal tests. In vitro
tests will be made for intestinal digestion, translocation
and exposure of the cells. Validation of the in vitro tests
will be done with in vivo data.
After these first presentations, a short coffee break followed.
James Holzwarth, senior scientist, gave a presentation with the title ‘Risk benefit evaluation of
phytochemicals’. He spoke about Nrf2 from the beneficial point of view (activation of phase II
enzymes) and Nrf2 from the toxicological point of view (toxic compounds like heavy metals can also
activate Nrf2 pathway). The aim of his research is to evaluate when Nrf2 activation is beneficial and
when not. The corresponding hypothesis is described as ‘cofactors may direct the Nrf2 activation into
protective or toxic pathways’ and the preliminary data seem to support this hypothesis.
Suzanne van den Berg spoke about the risk assessment of plant food supplements. She mentioned
the different approaches that will be used during her PhD-project including the margin of exposure
concept (MOE), of which she gave some results, the threshold of toxicological concern (TTC), the
mode of action (MOA) concept in which physiological based biokinetic (PBK) models will be
developed and finally the matrix concept.
This presentation was followed by ‘In vitro tests for thyroid hormone disruption’ presented by Barae
Jomaa. During his presentation Barae discussed the proliferation assay and thyroid hormone
(mediated expression) in GH3 cells and FRTL-5 cells. 12 compounds were tested and it was seen that
in vitro data do not completely reflect the in vivo data from literature.
17
Niek van der Pas elaborated on the PBK modelling for the prediction of cholesterol levels. He
mentioned that cholesterol-lowering drugs are widely used and that health claims approved by EFSA
include health claims on cholesterol. The aim of his research is to make a mathematical model of
cholesterol metabolism. The model shows correct predictions for 10 mutations in cholesterol
metabolism and correct predictions for the use of statins.
The last presentation before lunch was given by Elena Lo Piparo, research scientist. Her presentation
was entitled ‘Application of in silico methods in food chemical risk assessment’. Analytical chemistry
is detecting substances at lower and lower concentration. Tox-tree is a new and useful tool that
places chemicals into categories and predicts various kinds of toxic effect by applying decision tree
approaches. Modelling oral rat chronic toxicity for development of a more homogeneous database.
We had a very nice lunch during which we could mingle with the people working at Nestle.
After lunch Mohammed Ariful Islam (Arif) told about his PhD-
project: ‘Isoflavones: combine toxicological and
epidemiologic approaches’. Isoflavones are phytoestrogens,
mainly found in soy products, tofu, and supplements. In
literature, there is conflicting data about risk and benefits.
The exposure is reported to reach an amount up to 1 mg/kg
bw. The risks are based on in vitro data; however, there is
limited clinical data. Isoflavone levels will be measured in
supplements. Moreover, an animal study in rats and a human
study will be performed, and also PBK modelling will be of importance for his research.
Pascal Zbinden, research scientist, presented ‘The melamine case: science in the management of a
crisis’. In September 2008, in China, some babies fell sick with kidney stones and some died.
Melamine in infant formulas was identified as the hazard source of these fatal cases. Nestlé China
took action and put immediate measures in place to check the milk. In Nestlé products only traces of
melamine were found. Causes of presence of melamine in milk can include the following:
adulteration (intentionally added), insecticide contamination, food comes in contact with materials
(cross contamination), and/or enters the food chain via the cow feed. The trace levels found in Nestlé
products were actually not from adulteration of the milk but came from cows exposed to sources of
melamine via diet/environment. The cow feed was the key and solution of these traces found in the
end product. The overall food chain is now regularly checked.
We had a small coffee break that was followed by a presentation of the PhD-project of Reiko
Kiwamoto. The title of her presentation was ‘PBK and PBD models for α, β-unsaturated aldehydes’.
Reiko explained that α, β-unsaturated aldehydes are used as flavouring agents and are a concern for
genotoxicity. These compounds are possibly detoxified in vivo by GST or reduced to alcohol. The aim
of her project is to gain insight in doses at which detoxifying processes are saturated and toxicity
starts. She will use in vitro experiments to collect parameters as input for PBK/PBD modelling.
18
The last presentation of the day was given by Elise Hoek. In her presentation ‘Interaction of
flavonoids with FFA and TG assays’ she mentioned that assays to measure free fatty acids (FFA) and
triglycerides (TG) are based on a reaction with peroxidase enzyme. Peroxidase can be influenced by
the presence of flavonoids. If you add flavonoids, lower levels of FFA and TG were detected. It was
concluded to better use LCMS or other methods. Quercetin is metabolized so it is interesting to see
what happens in vivo.
19
European Food Safety Authority (EFSA), Parma (I)
The European Food Safety Authority (EFSA) is the keystone of European Union (EU) risk assessment
regarding food and feed safety. In close collaboration with national authorities and in open
consultation with its stakeholders, EFSA provides independent scientific advice and clear
communication on existing and emerging risks.
Time Title Presentation and Speaker
9.00 EFSA´s role in the European food safety system, by Michael Sulzner, LRA Unit
9.30 CONTAM panel risk assessment in the area of contaminants, by Marco Binaglia, CONTAM
Unit
10.00 Coffee break
10.20 NUTRI panel risk assessment in the area of novel foods, by Wolfgang Gelbmann, NUTRI
Unit
10.50 ANS panel risk assessment of food additives and nutrient sources, by Ms. Stavroula
Tasiopoulou, ANS unit
11.20 Discussion and Closing address
20
Minutes by: Reiko Kiwamoto and Niek van de Pas
During our visit to EFSA, four
interesting presentations
were given including EFSA’s
role in the European food
safety system, CONTAM
panel´s risk assessment in the
area of contaminants, NUTRI
panel’s risk assessment in the
area of novel foods, and the
ANS panel´s risk assessment
of food additives and nutrient
sources.
Mr. Michael Sulzner gave an overview of the European Food Safety Authority (EFSA), such as its
origin, EFSA’s mandate, its structure and how EFSA carries out risk assessment and risk
communication. Briefly, EFSA was established in 2002 in order to improve EU food safety, re-build
consumer confidence and re-build confidence of trading partners after BSE and dioxins crisis. Its
mandate is to provide scientific advice for EU legislations/policies and to communicate the risks, thus
risk assessment and risk communication in other words. There are presently 10 scientific panels for
risk assessment. In these panels, members do not represent their own member state, but present as
experts in the field. EFSA communicates with various stakeholders including risk managers and
assessors of member states, media, consumer organisations and industries.
More details on, for instance, the role of EFSA or panel members with regard to communication with
consumers, and how EFSA deals with on-going crisis was provided in response to the questions from
the participants.
Ms. Luisa Ramos Bordajandi gave a presentation about the CONTAM unit of the EFSA. She is a
pharmacist and joined EFSA 2.5 years ago. The CONTAM panel contains 21 members and is chaired
by Dr. Josef Schlater. This panel delivers opinions on contaminants in food and feed.
The presenter explained that a project is usually started after a request by the European
Commission, but initiative of the panel is also possible. After the start of a project, a working group is
constructed. This group writes a draft opinion to the panel. Once adopted, results are published in
the EFSA Journal and the EFSA website. Examples of conclusions can be: ‘X is not a health concern’, ‘X
is unlikely to raise concern’, ‘X is a potential risk’. In the risk assessment, more sensitive groups are
taken into account. The presenter stresses that risk assessment occur in cooperation with the
member states. This procedure was illustrated with a case study: Brominated Flame Retardants (BFR)
in Food.
Dr. Wolfgang Gelbmann from NUTRI Unit explained how EFSA performs risk assessment on novel
food. Novel food is defined as “food or its ingredients which have not been used for human
consumption to a significant degree within the EU before 15 May 1997”. The scope includes new
substances such as nanomaterial as well as conventional substances which are derived by using a
new process such as lycopene produced by genetically modified microorganisms or products from
21
clone animal. GMOs were excluded from the scope in 2002, as a result of the implementation of a
GMOs specific regulation.
Applicants need to provide information on specification, production process, history of their
consumption, anticipated intake and nutritional and toxicological aspect of the food of concern.
Currently the regulation on novel food ((EC)N 258/97) is under revision process mainly due to the
increased concern expressed by trading partners under WTO (World Trade Organisation). The
revision aims at lessening the applicants’ burden, transferring all the responsibility on risk
assessment which is partly on Member States to EFSA, and excluding clone animal products from the
scope. However, because of stakeholders’ high interest on clone animal, the adoption of proposed
draft was rejected and it is unclear when it will be revised for now.
Participants asked details on overlap in risk assessment burden between Member States (e.g. when
Member States give comments on EFSA’s risk assessment on novel food), the acceptance of in silico
methods, time length from application to risk assessment completion and so on.
Ms. Stavroula Tasiopoulou gave a lecture about the work of the ANS panel that deals with food
Additives and Nutrient Sources added to food. It deals with new applications and re-evaluates risk
assessments that were performed by EFSA’s predecessor. In 10 years, the ANS unit should re-
evaluate 300 food additives and evaluates 10-20 new applications per year. Examples of substances
evaluated by this ANS panel are aspartame, anti-oxidants, and food colours. Re-evaluation of Food
Colours should be finished in 2015, Components other than colours and sweeteners in 2018, and
Sweeteners in 2020.
The evaluation is based on among others: the chemical identity, the manufacturing process and
exposure data. If data is not available to EFSA, EFSA will have an ‘open call’ for data. Member states
and companies can send the data in a standard format. If uncertainties remain, they are included in
the final advice to the EU.
22
Final remarks
Throughout our study tour to Switzerland and Italy we made visits to different companies and
institutes in the field of Toxicology. We believe that this trip gave us the opportunity to extend our
knowledge and network, which may not only have an important impact on our PhD research but also
on our future careers. Moreover, we feel that this trip was a good opportunity to promote our
department abroad and cooperate with foreign institutes. Apart from the visits to the companies and
institutes, we had time for some social activities to strengthen the relationship between the PhD-
students of our department. So in conclusion, we can look back on a successful study tour, both from
a scientific and social point of view.
Organizing this trip captured a lot of our time and we encountered some difficulties especially with
regard to the financial part of the trip. However, it was also a lot of fun and it was a nice learning
experience. This was the first time that such an international PhD-trip was organized at the division
of Toxicology. We hope that in the future more of these trips will follow and we wish the next
organizing committee(s) a lot of luck, joy and wisdom.
Finally, we would like to thank the Nestlé Research Center, SOIT, Jan Koeman Fonds, LEB funding,
P&L drukkerijen and the research schools VLAG and SENSE for financial support.
The organizing committee,
Alicia Paini, Si Wang, Karsten Beekmann, Merel Van der Ploeg, Suzanne van den Berg
Website: http://www.tox.wur.nl/UK/PhD+Trip+2011/
23
Staff at the Division of Toxicology
Head of the Division of toxicology
Prof. Dr. Ir. I.M.C.M Rietjens
PhD Students
Suzanne van den Berg [email protected]
Nynke Evers [email protected]
Linda Gijsbers [email protected]
Elise Hoek – van den Hil [email protected]
Ariful Islam Mohammed [email protected]
Baraee Jomaa [email protected]
Reiko Kiwamoto [email protected]
Jochem Louisse [email protected]
Alicia Paini [email protected]
Niek van de Pas [email protected]
Merel van der Ploeg [email protected]
Agata Walczak [email protected]
Si Wang [email protected]
Co-worker
Laura de Haan [email protected]
Division of Toxicology phone: 0317 48 21 37
fax: 0317 48 49 31
E-mail: [email protected]
Visitors address
De Dreijen - Tuinlaan 5
Building 320
6703 HE Wageningen
The Netherlands
Postal address
Postbus 8000
6700 EA Wageningen
The Netherlands
Website: http://www.tox.wur.nl/UK/
24
Picture impression during social activities
25
26
Sponsors
Jan Koeman Fonds