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

Overview

This document provides additional regional assessments of the status of metal concentrations in biota based on human health rather than environmental thresholds. The regional assessments are part of the 2022 OSPAR CEMP assessment and concern the metals CD, PB, and HG which are compared against the Maximum Permissible Concentration (MPC). 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 metal. This is the only place where trends are presented as the focus of this document is on status relative to the MPC.

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

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


CD


PB


HG


Trend summary (numbers)

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

OSPAR region MIME region status CD PB HG total
1 Barents Sea upward trend 1 0 2 3
no trend 7 7 6 20
downward trend 1 1 2 4
Greenland-Scotland ridge upward trend 3 1 5 9
no trend 10 5 12 27
downward trend 2 1 1 4
East of Iceland upward trend 0 0 3 3
no trend 0 0 7 7
downward trend 0 0 0 0
Norwegian Sea upward trend 0 0 1 1
no trend 4 3 3 10
downward trend 1 2 1 4
total upward trend 4 1 11 16
no trend 21 15 28 64
downward trend 4 4 4 12
2 Norwegian Trench upward trend 0 0 3 3
no trend 6 8 11 25
downward trend 9 7 3 19
Northern North Sea upward trend 7 4 9 20
no trend 16 20 29 65
downward trend 8 7 5 20
Skagerrak and Kattegat upward trend 6 6 12 24
no trend 22 17 18 57
downward trend 3 8 3 14
Southern North Sea upward trend 12 7 10 29
no trend 27 30 41 98
downward trend 4 5 4 13
Channel upward trend 17 15 15 47
no trend 11 13 17 41
downward trend 0 0 0 0
total upward trend 42 32 49 123
no trend 82 88 116 286
downward trend 24 27 15 66
3 Irish and Scottish West Coast upward trend 3 2 2 7
no trend 22 26 23 71
downward trend 6 4 0 10
Irish Sea upward trend 4 4 5 13
no trend 25 34 35 94
downward trend 11 7 6 24
Celtic Sea upward trend 6 5 8 19
no trend 16 18 11 45
downward trend 7 7 5 19
total upward trend 13 11 15 39
no trend 63 78 69 210
downward trend 24 18 11 53
4 Northern Bay of Biscay upward trend 9 9 13 31
no trend 28 27 21 76
downward trend 0 1 0 1
Iberian Sea upward trend 5 1 2 8
no trend 20 19 20 59
downward trend 7 11 8 26
Gulf of Cadiz upward trend 0 0 0 0
no trend 1 2 1 4
downward trend 0 0 1 1
total upward trend 14 10 15 39
no trend 49 48 42 139
downward trend 7 12 9 28


Trend summary (proportions)

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

OSPAR region MIME region status CD PB HG total
1 Barents Sea upward trend 11 0 20 11
no trend 78 88 60 74
downward trend 11 12 20 15
Greenland-Scotland ridge upward trend 20 14 28 22
no trend 67 72 67 68
downward trend 13 14 5 10
East of Iceland upward trend 30 30
no trend 70 70
downward trend 0 0
Norwegian Sea upward trend 0 0 20 7
no trend 80 60 60 66
downward trend 20 40 20 27
total upward trend 14 5 26 17
no trend 72 75 65 70
downward trend 14 20 9 13
2 Norwegian Trench upward trend 0 0 17 6
no trend 40 53 65 53
downward trend 60 47 18 41
Northern North Sea upward trend 22 13 21 19
no trend 52 64 67 62
downward trend 26 23 12 19
Skagerrak and Kattegat upward trend 19 19 36 25
no trend 71 55 55 60
downward trend 10 26 9 15
Southern North Sea upward trend 28 17 18 21
no trend 63 71 75 70
downward trend 9 12 7 9
Channel upward trend 61 54 47 53
no trend 39 46 53 47
downward trend 0 0 0 0
total upward trend 28 22 27 26
no trend 56 60 65 60
downward trend 16 18 8 14
3 Irish and Scottish West Coast upward trend 10 6 8 8
no trend 71 81 92 81
downward trend 19 13 0 11
Irish Sea upward trend 10 9 11 10
no trend 62 75 76 72
downward trend 28 16 13 18
Celtic Sea upward trend 21 17 33 23
no trend 55 60 46 54
downward trend 24 23 21 23
total upward trend 13 10 16 13
no trend 63 73 73 69
downward trend 24 17 11 18
4 Northern Bay of Biscay upward trend 24 24 38 29
no trend 76 73 62 70
downward trend 0 3 0 1
Iberian Sea upward trend 16 3 7 9
no trend 62 61 66 63
downward trend 22 36 27 28
Gulf of Cadiz upward trend 0 0 0 0
no trend 100 100 50 80
downward trend 0 0 50 20
total upward trend 20 14 23 19
no trend 70 69 63 67
downward trend 10 17 14 14


Status summary (numbers)

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

OSPAR region MIME region status CD PB HG total
1 Barents Sea green 11 11 11 33
red 0 0 0 0
Greenland-Scotland ridge green 8 10 11 29
red 2 0 0 2
Norwegian Sea green 6 6 6 18
red 0 0 0 0
total green 25 27 28 80
red 2 0 0 2
2 Norwegian Trench green 15 14 17 46
red 0 1 0 1
Northern North Sea green 36 42 35 113
red 6 4 0 10
Skagerrak and Kattegat green 42 40 42 124
red 0 2 0 2
Southern North Sea green 39 53 48 140
red 10 3 1 14
Channel green 33 34 33 100
red 0 0 0 0
total green 165 183 175 523
red 16 10 1 27
3 Irish and Scottish West Coast green 34 34 32 100
red 1 1 0 2
Irish Sea green 58 62 51 171
red 0 5 0 5
Celtic Sea green 38 40 37 115
red 0 0 0 0
total green 130 136 120 386
red 1 6 0 7
4 Northern Bay of Biscay green 42 45 45 132
red 3 0 0 3
Iberian Sea green 39 37 36 112
red 0 2 0 2
Gulf of Cadiz green 3 3 3 9
red 0 0 0 0
total green 84 85 84 253
red 3 2 0 5


Status summary (proportions)

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

OSPAR region MIME region status CD PB HG total
1 Barents Sea green 100 100 100 100
red 0 0 0 0
Greenland-Scotland ridge green 80 100 100 94
red 20 0 0 6
Norwegian Sea green 100 100 100 100
red 0 0 0 0
total green 93 100 100 98
red 7 0 0 2
2 Norwegian Trench green 100 93 100 98
red 0 7 0 2
Northern North Sea green 86 91 100 92
red 14 9 0 8
Skagerrak and Kattegat green 100 95 100 98
red 0 5 0 2
Southern North Sea green 80 95 98 91
red 20 5 2 9
Channel green 100 100 100 100
red 0 0 0 0
total green 91 95 99 95
red 9 5 1 5
3 Irish and Scottish West Coast green 97 97 100 98
red 3 3 0 2
Irish Sea green 100 93 100 97
red 0 7 0 3
Celtic Sea green 100 100 100 100
red 0 0 0 0
total green 99 96 100 98
red 1 4 0 2
4 Northern Bay of Biscay green 93 100 100 98
red 7 0 0 2
Iberian Sea green 100 95 100 98
red 0 5 0 2
Gulf of Cadiz green 100 100 100 100
red 0 0 0 0
total green 97 98 100 98
red 3 2 0 2


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 MPC. The regional status for each metal is then estimated by fitting the following linear mixed model by restricted maximum likelihood:

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

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 metal 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.


OSPAR region 1


OSPAR region 2


OSPAR region 3


OSPAR region 4


Regional status compared to the Maximum Permissible Concentration (MPC)

The first 3 tabs show:

  • Regional status by metal: regional status estimates for each metal with pointwise upper one-sided 95% confidence intervals plotted by metal
  • Regional status by region: regional status estimates for each metal 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 MPC
  • red: the mean concentration is not significantly below the MPC

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


Regional status by metal


Regional status by region


Individual time series


Estimates by region and metal

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

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


MIME region metal status se upper concentration conc upper
Barents Sea CD -1.94 0.27 -1.50 0.14 0.22
PB -3.28 0.28 -2.82 0.04 0.06
HG -3.17 0.27 -2.73 0.04 0.07
Greenland-Scotland ridge CD -0.83 0.29 -0.35 0.44 0.70
PB -4.13 0.34 -3.57 0.02 0.03
HG -3.73 0.27 -3.28 0.02 0.04
Norwegian Sea CD -2.89 0.37 -2.28 0.06 0.10
PB -3.70 0.37 -3.10 0.02 0.05
HG -2.67 0.37 -2.06 0.07 0.13
Norwegian Trench CD -2.35 0.23 -1.96 0.10 0.14
PB -2.42 0.24 -2.03 0.09 0.13
HG -2.51 0.22 -2.15 0.08 0.12
Northern North Sea CD -1.59 0.16 -1.33 0.20 0.26
PB -1.80 0.16 -1.54 0.17 0.21
HG -2.16 0.15 -1.90 0.12 0.15
Skagerrak and Kattegat CD -1.98 0.14 -1.75 0.14 0.17
PB -2.75 0.14 -2.52 0.06 0.08
HG -2.93 0.14 -2.70 0.05 0.07
Southern North Sea CD -1.61 0.14 -1.39 0.20 0.25
PB -2.72 0.13 -2.51 0.07 0.08
HG -2.11 0.13 -1.89 0.12 0.15
Channel CD -2.04 0.16 -1.78 0.13 0.17
PB -2.03 0.16 -1.77 0.13 0.17
HG -2.84 0.16 -2.58 0.06 0.08
Irish and Scottish West Coast CD -2.14 0.17 -1.87 0.12 0.15
PB -2.88 0.17 -2.61 0.06 0.07
HG -3.47 0.17 -3.20 0.03 0.04
Irish Sea CD -2.27 0.13 -2.06 0.10 0.13
PB -1.96 0.12 -1.76 0.14 0.17
HG -2.75 0.13 -2.54 0.06 0.08
Celtic Sea CD -2.16 0.15 -1.92 0.11 0.15
PB -2.19 0.15 -1.94 0.11 0.14
HG -3.37 0.15 -3.12 0.03 0.04
Northern Bay of Biscay CD -1.42 0.13 -1.20 0.24 0.30
PB -1.93 0.13 -1.71 0.15 0.18
HG -2.70 0.13 -2.48 0.07 0.08
Iberian Sea CD -2.53 0.15 -2.28 0.08 0.10
PB -2.25 0.15 -2.00 0.11 0.14
HG -3.51 0.15 -3.26 0.03 0.04
Gulf of Cadiz PB -3.92 0.55 -3.01 0.02 0.05
HG -3.99 0.52 -3.15 0.02 0.04