Regional assessment of status against human health thresholds in PAH concentrations in biota

Overview

This document provides additional regional assessments of the status of PAH concentrations in biota based on human health rather than environmental thresholds. The regional assessments are part of the 2023 OSPAR CEMP assessment and concern the PAHs BAP and FLU which are compared against the Quality Standard human health (QShh). Methodological details are only described briefly: further information can be found here.


Summary of individual time series results

This section summarises the individual time series assessments of trend and status for each PAH. This is the only place where trends are presented as the focus of this document is on status relative to the QShh.

The first set of tabs show the trend and status assessments for each PAH in turn. The colours have the following meaning:

  • green: the mean concentration is significantly (p < 0.05) below the QShh
  • red: the mean concentration is not signficantly below the QShh
  • black: there are no assessment criteria available

And the shapes have the following meaning:

  • downward triangle: the mean concentration is significantly decreasing (p < 0.05)
  • circle: there is no significant change in mean concentration (p > 0.05) or there are too few years to test for trends
  • upward triangle: the mean concentration is significantly increasing (p < 0.05)

The second set of tabs give:

  • the number of time series with upwards, downwards or no trend in each MIME and OSPAR region
  • the same information presented as proportions
  • the number of time series with green or red status in each MIME and OSPAR region
  • the same information presented as proportions


BAP


FLU


Trend summary (numbers)

Number of time series with upwards, downwards or no trend by MIME and OSPAR region

OSPAR region MIME region status BAP FLU total
1 Barents Sea upward trend 0 0 0
no trend 0 1 1
downward trend 1 1 2
Greenland-Scotland ridge upward trend 0 0 0
no trend 0 4 4
downward trend 1 0 1
Norwegian Sea upward trend 0 0 0
no trend 0 0 0
downward trend 1 1 2
total upward trend 0 0 0
no trend 0 5 5
downward trend 3 2 5
2 Northern North Sea upward trend 0 0 0
no trend 1 8 9
downward trend 1 8 9
Skagerrak and Kattegat upward trend 1 1 2
no trend 5 7 12
downward trend 1 5 6
Southern North Sea upward trend 0 0 0
no trend 7 16 23
downward trend 4 1 5
Channel upward trend 5 0 5
no trend 12 19 31
downward trend 2 1 3
total upward trend 6 1 7
no trend 25 50 75
downward trend 8 15 23
3 Irish and Scottish West Coast upward trend 1 1 2
no trend 12 12 24
downward trend 1 3 4
Irish Sea upward trend 4 5 9
no trend 8 15 23
downward trend 2 2 4
Celtic Sea upward trend 3 0 3
no trend 18 14 32
downward trend 0 5 5
total upward trend 8 6 14
no trend 38 41 79
downward trend 3 10 13
4 Northern Bay of Biscay upward trend 2 0 2
no trend 18 16 34
downward trend 0 4 4
Iberian Sea upward trend 6 4 10
no trend 17 18 35
downward trend 4 5 9
total upward trend 8 4 12
no trend 35 34 69
downward trend 4 9 13


Trend summary (proportions)

Proportion of time series with upwards, downwards or no trend by MIME and OSPAR region

OSPAR region MIME region status BAP FLU total
1 Barents Sea upward trend 0 0 0
no trend 0 50 33
downward trend 100 50 67
Greenland-Scotland ridge upward trend 0 0 0
no trend 0 100 80
downward trend 100 0 20
Norwegian Sea upward trend 0 0 0
no trend 0 0 0
downward trend 100 100 100
total upward trend 0 0 0
no trend 0 71 50
downward trend 100 29 50
2 Northern North Sea upward trend 0 0 0
no trend 50 50 50
downward trend 50 50 50
Skagerrak and Kattegat upward trend 14 8 10
no trend 72 54 60
downward trend 14 38 30
Southern North Sea upward trend 0 0 0
no trend 64 94 82
downward trend 36 6 18
Channel upward trend 26 0 13
no trend 63 95 79
downward trend 11 5 8
total upward trend 15 1 7
no trend 64 76 71
downward trend 21 23 22
3 Irish and Scottish West Coast upward trend 7 6 7
no trend 86 75 80
downward trend 7 19 13
Irish Sea upward trend 29 23 25
no trend 57 68 64
downward trend 14 9 11
Celtic Sea upward trend 14 0 8
no trend 86 74 80
downward trend 0 26 12
total upward trend 16 10 13
no trend 78 72 75
downward trend 6 18 12
4 Northern Bay of Biscay upward trend 10 0 5
no trend 90 80 85
downward trend 0 20 10
Iberian Sea upward trend 22 15 18
no trend 63 67 65
downward trend 15 18 17
total upward trend 17 9 13
no trend 74 72 73
downward trend 9 19 14


Status summary (numbers)

Number of time series with each status by MIME and OSPAR region

OSPAR region MIME region status BAP FLU total
1 Barents Sea green 1 2 3
red 1 0 1
Greenland-Scotland ridge green 7 7 14
red 0 0 0
Norwegian Sea green 1 1 2
red 0 0 0
total green 9 10 19
red 1 0 1
2 Northern North Sea green 7 17 24
red 4 2 6
Skagerrak and Kattegat green 17 20 37
red 2 1 3
Southern North Sea green 19 19 38
red 2 2 4
Channel green 23 23 46
red 1 0 1
total green 66 79 145
red 9 5 14
3 Irish and Scottish West Coast green 20 21 41
red 0 0 0
Irish Sea green 20 28 48
red 10 3 13
Celtic Sea green 27 27 54
red 0 0 0
total green 67 76 143
red 10 3 13
4 Northern Bay of Biscay green 32 32 64
red 0 0 0
Iberian Sea green 32 33 65
red 6 5 11
total green 64 65 129
red 6 5 11


Status summary (proportions)

Proportion of time series with each status by MIME and OSPAR region

OSPAR region MIME region status BAP FLU total
1 Barents Sea green 50 100 75
red 50 0 25
Greenland-Scotland ridge green 100 100 100
red 0 0 0
Norwegian Sea green 100 100 100
red 0 0 0
total green 90 100 95
red 10 0 5
2 Northern North Sea green 64 89 80
red 36 11 20
Skagerrak and Kattegat green 89 95 92
red 11 5 8
Southern North Sea green 90 90 90
red 10 10 10
Channel green 96 100 98
red 4 0 2
total green 88 94 91
red 12 6 9
3 Irish and Scottish West Coast green 100 100 100
red 0 0 0
Irish Sea green 67 90 79
red 33 10 21
Celtic Sea green 100 100 100
red 0 0 0
total green 87 96 92
red 13 4 8
4 Northern Bay of Biscay green 100 100 100
red 0 0 0
Iberian Sea green 84 87 86
red 16 13 14
total green 91 93 92
red 9 7 8


Regional assessment - methods

For a regional status assessment, the status of each time series is summarised by the difference between the estimated mean log concentration in the final monitoring year and the log QShh. The regional status for each PAH is then estimated by fitting the following linear mixed model by restricted maximum likelihood:

  • response: status (mean log concentration - log QShh)
  • fixed model: region.PAH
  • random model: station + station.PAH + status estimation variation + residual variation

Note that the fixed effects model differs from that used in the regional status assessment against environmental thresholds. Here there are only two PAHs and a separate regional trend is fitted for each. In the assessment against environmental thresholds there are ten PAHs. These are regarded as random effects and a common regional status is estimated averaged across PAHs.

There are no restrictions on the time series used in the status meta-analysis based on the classification of the monitoring station; time series from baseline, representative and impacted stations are all included. However, the few time series with a non-parametric assessment of status must be excluded, because there is no summary measure of status to use in the mixed model.

The meta-analysis is restricted to regions and PAH combinations with at least three status stations with good geographic spread.

The results of the status regional assessments are back-transformed for presentation. The estimated regional status is then interpreted as the ratio of the mean regional concentration to the assessment concentration. For example, a value of 1 indicates that the mean regional concentration is equal to the assessment concentration; a value of 0.5 indicates that it is half the assessment concentration, and a value of 2 indicates that it is twice the assessment concentration.


Regional assessment - availability of time series

This section provides more detail on the number and geographic spread of the time series available for the meta-analyses. The tabs show the stations with parametric status assessments for each OSPAR region in turn. The following regions have an insufficient number or time series or spread of stations and are excluded from the regional assessment: Barents Sea and Norwegian Sea. `


OSPAR region 1


OSPAR region 2


OSPAR region 3


OSPAR region 4


Regional status compared to the Quality Standard human health (QShh)

The first 3 tabs show:

  • Regional status by PAH: regional status estimates for each PAH with pointwise upper one-sided 95% confidence intervals plotted by PAH
  • Regional status by region: regional status estimates for each PAH with pointwise upper one-sided 95% confidence intervals plotted by region
  • Individual time series: the status estimates from the individual time series on which the regional assessment is based. The estimates for regions with insufficient geographic spread (and excluded from the meta-analysis) are also shown.

The symbols in all the plots have the following interpretation:

  • green: the mean concentration is significantly (p < 0.05) below the QShh
  • red: the mean concentration is not significantly below the QShh

The final tab shows the estimates of the regional status by PAH.


Regional status by PAH


Regional status by region


Individual time series


Estimates by region and PAH

This table shows the estimates of the regional trend by determinand:

  • status: the estimated mean log concentration minus the log QShh
  • se: the corresponding standard error
  • upper: the corresponding pointwise upper one-sided 95% confidence limit
  • concentration: the estimated mean concentration relative to the QShh
  • conc upper: the corresponding pointwise upper one-sided 95% confidence limit


MIME region PAH status se upper concentration conc upper
Greenland-Scotland ridge BAP -4.47 0.55 -3.56 0.01 0.03
FLU -4.39 0.40 -3.72 0.01 0.02
Northern North Sea BAP -1.28 0.32 -0.75 0.28 0.47
FLU -1.93 0.20 -1.60 0.15 0.20
Skagerrak and Kattegat BAP -2.46 0.21 -2.11 0.09 0.12
FLU -2.48 0.19 -2.16 0.08 0.12
Southern North Sea BAP -2.43 0.22 -2.08 0.09 0.13
FLU -2.19 0.20 -1.86 0.11 0.16
Channel BAP -2.51 0.18 -2.22 0.08 0.11
FLU -2.25 0.17 -1.96 0.11 0.14
Irish and Scottish West Coast BAP -3.49 0.20 -3.16 0.03 0.04
FLU -2.57 0.19 -2.26 0.08 0.10
Irish Sea BAP -1.67 0.16 -1.41 0.19 0.25
FLU -1.26 0.16 -1.00 0.28 0.37
Celtic Sea BAP -3.09 0.17 -2.82 0.05 0.06
FLU -2.68 0.16 -2.41 0.07 0.09
Northern Bay of Biscay BAP -2.75 0.15 -2.50 0.06 0.08
FLU -2.42 0.15 -2.18 0.09 0.11
Iberian Sea BAP -1.96 0.15 -1.72 0.14 0.18
FLU -1.99 0.14 -1.76 0.14 0.17