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Acrylamide in Food State of the Art
Dr. Rüdiger Weißhaar
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Chronology (1)

• 1997 - The Hallandsas Tunnel in Sweden
• Acrylamide from groutings streamed into ambient
  waters
• Dead fish and paralyzed cows
• Acrylamide in private wells
• Agricultural products from the whole area were
  discarded

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Chronology (2)

• 1997 2001 Acrylamide biomarker analysis
• Acrylamide-Hb-Adduct not only in exposed
  workers, but also in unexposed control persons
• Elevated AA-Hb-Adducts in rats fed with fried
  feed
• Acrylamide A cooking carcinogen ?
  M. Tornqvist et al. ,Chem. Res. Toxicol. (2000)

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Chronology (3)

• Development of a LC-MS-MS-method and broad survey
  of common food products in Sweden.
• 24. April 2002 Swedisch National Food
  Administration informed international authorities
  about the finding of acrylamide in many types of
  heat processed foods.
• Since April 2002 Worldwide survey and research
  about acrylamide in food.

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Toxicological aspects (1)

• Acrylamide is neurotoxic for humans
• NOAEL for peripheral neuropathy 500 µg/kg bw/d
• Estimated intake (Germany) 0,6 µg/kg bw/d
• Young people consuming high amounts of potato
  chips and french fries 3,5 µg/kg bw/day)
• There are no indications for any neurotoxic
  effect of foodborne acrylamide, because of the
  high margin between exposure and NOAEL

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Toxicological aspects (2)

• Acrylamide induces tumors in rats and mice
• Acrylamide and Glycidamide are genotoxic
• There is no treshold level known for the action
  of acrylamide on DNA
• IARC classification for acrylamide
• Probably carcinogenic to humans
• Reevaluation of a population based study in
  Sweden (Mucci et al., 2003) No effect of fried
  food on the risk for three frequent types of
  cancer

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Toxicological aspects (3) J. Schlatter BAG
Switzerland 2002

• Margin of Exposure

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Toxicological aspects (4)

• 27.06.2002 WHO Expert Consultation
• The consultation recognized the presence of
  acrylamide in foods as a major concern in humans
  based on the ability to induce cancer and
  heritable mutations in laboratory animals

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LC-MS-MS-Method

• Extraktion with water
• Purification of water extract (precipitation,
  SPE)
• LC-MS-MS (ESI)
• No enrichment step for acrylamide !

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GC-MS-Method / Derivatisation with bromine

• Extraktion with water
• Bromination of water extract

• Extraction of dibromopropionylamide with
  ethylacetate
• Evaporation of solvent (enrichment step)
• GC-MS (characteristic dibromine pattern)

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Detection methods
Distribution of detection techniques used in
proficiency tests (2002)
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Method performance (simple matrices)
LOD RSD GC-MS 1 - 50
µg/kg 4-8 LC-MS-MS 10-25 µg/kg 2-10 (0,2-1
µg/kg) High sophisticated (high price)
LC-MS-MS-systems optimized for low-mass-range
detection
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Presuppositions for acrylamide formation

• Free asparagine

• Free reducing sugar (e.g. glucose, fructose)

• Low water activity

• Product temperature gt 100C

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Mechanism of acrylamide formation
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Formation of acrylamide in potato products
Asparagine is a nitrogen reservoir for the
potato. Level of reducing sugars is the limiting
factor. Fresh potatoes only have low levels of
reducing sugars. Levels of reducing sugars
increase during storage. Dramatic increase of
reducing sugars takes place, if storage
temperatures are below 8C or if potatoes become
green.
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Acrylamide in French fries at different frying
temperatures
Recommendation Maximum frying temperature 175C
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Cereal products Asparagine is the limiting
factor !

Flour was mixed with water and precursors and
heated under controlled condicions I no
precursor added II 5 glucose/fructose III
1 asparagine

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Acrylamide increases with dough maturing time

Wheat and rye flour was pasted with water. The
resulting doughs were stored at 25C for
different times and then heated under controlled
condicions.

wheat flour rye flour
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Effect of ammonium hydrogencarbonate

Wheat and rye flour was pasted with water. To a
portion, ammonium-hydrogencarbonate was added.
Doughs were heated under controlled condicions.

wheat flour rye flour
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Ammoniumhydrogencarbonate mode of action
Wheat flour was pasted with water and different
additives. Doughs were heated under controlled
condicions.


I no additive II asparaginic acid III
NH4HCO3 IV asparaginic acid NH4HCO3
V lactic acid NH4HCO3
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Ammonium salts mode of action (hypothesis)
CH3 CH(OH) COO NH4


microbiological ? ? T ? - H2O
CH2 CH COO NH4
? T - H2O
CH2 CH CO NH2
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Acrylamid levels in Food
Food Classes N Range µg/kg Range µg/kg Median µg/kg Signal Value N gt Signal Value
Food Classes N min. max. Median µg/kg Signal Value N gt Signal Value
potato chips 192 140 3640 819 1000 76
french fries 98 lt 10 2779 151 570 11
biscuits, cakes 38 lt 10 1090 190 660 4
Coffee powder 30 115 1685 343 370 14
crisp bread 32 15 1714 133 610 8
breakfast cereals 32 lt 10 846 65 260 4
others 308 lt 10 4594 30 1000 16

Lebensmittelüberwachung Baden-Württemberg, May
2003-April 2003
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Data base on Acrylamide levels in Food

As a joint DG SANCO- DG JRC initiative a
monitoring data base on acrylamide levels in food
was launched in April 2003. Data from official,
private, industrial and research
laboratories. Contact www.irmm.jrc.be/ffu.html
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Proficiency Tests at EU level
Two proficiency test for official food control
laboratories at EU level are planned in 2003 A
test with simple matrices (crisp bread, butter
cookies) organized by JRC-IRMM, running now. A
second proficiency test, jointly organized by
the JRC-IRMM and the German BfR with difficult
matrices (cocoa powder, coffee powder) in autumn
2003.


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... Thank you very much for your friendly
attention