Difference between revisions of "POPs in Baltic herring"

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m (Answer)
m (Rationale)
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== Rationale ==
 
== Rationale ==
 +
 +
This model takes in measured congener concentrations of POPs in Baltic herring in northern bart of Baltic sea. Measured data is used for Bayesian model to produce posterior medians and sds for each congener and also to calculate TEQ values. Numerical results are saved as variables to Opasnetbase and result figures are presented above in the Answer section.
  
 
<rcode name="pop_bayes" label="Calculate (for developers only)" graphics=1 store=1>
 
<rcode name="pop_bayes" label="Calculate (for developers only)" graphics=1 store=1>
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   Meanorig = aggregate(compdat$Result, compdat["POP"], mean), #calculate mean for original data
 
   Meanorig = aggregate(compdat$Result, compdat["POP"], mean), #calculate mean for original data
 
   Sdorig = aggregate(compdat$Result, compdat["POP"], sd)$x, #calcaulte sd of original data
 
   Sdorig = aggregate(compdat$Result, compdat["POP"], sd)$x, #calcaulte sd of original data
 +
  Medianorig = aggregate(compdat$Result, compdat["POP"], median)$x, #calculate median of original data
 
   Meanlog = aggregate(Compound, compdat["POP"], mean)$x, #calculate mean for logdata
 
   Meanlog = aggregate(Compound, compdat["POP"], mean)$x, #calculate mean for logdata
 
   Sdlog = aggregate(Compound, compdat["POP"], sd)$x, #calculate sd for logdata
 
   Sdlog = aggregate(Compound, compdat["POP"], sd)$x, #calculate sd for logdata
 
   Meanlogpost = Meanlogpost,
 
   Meanlogpost = Meanlogpost,
 
   Sdlogpost = Sdlogpost,
 
   Sdlogpost = Sdlogpost,
   Meanpost = 10^Meanlogpost-1E-02,
+
   Medianpost = 10^Meanlogpost-1E-02,
   Sdpost = 10^Sdlogpost-1E-02
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   Sdpost = 10^Sdlogpost-1E-02 #this might be incorrect
 
   )
 
   )
  

Revision as of 12:08, 21 June 2016



Question

What are the concentrations of persistent organic pollutants (POPs) in Baltic herring.

Answer

Answer is under work and results are preliminary.

POP concentrations in Baltic sea fish have been measured from samples collected in EU-kalat project. The original data of individual fish samples si accessible through Opasnet base. This data is used here for a Bayesian model to calculate posterior distributions (mean and SD) for each congener. This data is then translated into TEQ to be used for health impact assessment of Baltic herring.

Posterior congener mean concentrations are presented below for each compound group (PCDD/F, PCB, BDE) taken under analysis in EU-kalat.

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Based on the mean posterior concentrations of individual congeners, TEQs are calculated for each congener by using TEF values by WHO and plotted below.

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+ Show code

Rationale

This model takes in measured congener concentrations of POPs in Baltic herring in northern bart of Baltic sea. Measured data is used for Bayesian model to produce posterior medians and sds for each congener and also to calculate TEQ values. Numerical results are saved as variables to Opasnetbase and result figures are presented above in the Answer section.

+ Show code

See also

References