Institute for Environmental Studies (IVM) 1

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Sampling seafood for assessment of TBT exposure
Did we get it right?
Willemsen, FH1, Morabito, R2, Wegener, JW1

• EU-supported project QLK1-2001-01437 OT-SAFE

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Aim of OT-SAFE

• to assess the risk of TBT in seafood for
  European consumers
• Tolerable daily intake has been established at
  (0.25µg/kg bodyweight)
• Leaves
• differences in bodyweight (differs with age, sex,
  geographic region, etc.)
• exposure

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Estimating the exposure level

• Exposure through seafood only
• -realistic scenario
• Exposure S Seafood t,x TBT-content t,x
• For as many foods as feasible with
• t time of the catch (if necessary)
• x location (if necessary)

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Estimating the exposure level

• Necessary data is consumption data
• Dutch Seafood Consumption (1997)

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Seafood consumption data

• Food consumption data

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(No Transcript)
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Seafood consumption data (NL)
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Sampling strategy

• Expected TBT-levels from literature
• Consumption figures (as detailed as possible)
• Calculate expected relative contribution
• If feasible, differentiate for location

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Estimating the exposure level

• Figures on TBT-content
• First estimate (NL-example) based on taxonomic
  groups and regional specifics

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Estimating the exposure level, example
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Sampling procedure

• 174 samples in total
• 28 species
• Almost 50 of samples are molluscs and
  cephalopods

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So did we get it right?

• Pro Preliminary data suggests that the
  assumptions are born out, e.g. low conc. in
  pelagic fish
• Contra There is still a spread in
  concentrations, that we cannot explain