Regional assessment of status and trends in PBDE concentrations in biota

  • Overview
  • Summary of individual time series results
  • Regional assessment - methods
  • Regional assessment - availability of time series
  • Regional trends
  • Regional status compared to the Federal Environmental Quality Guideline (FEQG)
  • Regional status compared to the Background Assessment Concentration (BAC)
  • PBDE profiles

Overview

The 2022 OSPAR CEMP assessment describes the status and trends of contaminant concentrations in biota and sediment at monitoring stations in the OSPAR area. Assessments are made for a large number of time series, each of a single contaminant in a single species and tissue (for biota) at a single monitoring station. This document is one of a series that synthesises the results of the individual time series to assess status and trends at the MIME regional level. In particular, it considers PBDE concentrations in biota, where the PBDEs are BDE28, BDE47, BDE66, BDE85, BDE99, BD100, BD126, BD153, BD154, BD183, BD209. For simplicity, the term ‘region’ is used throughout to describe MIME regions. OSPAR regions are always referred to as such.

The regional status assessments presented in this document are based on environmental thresholds. Regional status assessments based on human health tresholds can be found here.

The regional status assessments presented in this document are integrated with regional status assessments for other contaminants and biological effects using the CHASE approach. Details can be found here.

The following sections:

  • summarise the individual time series results
  • describe the methods used to combine the individual time series results to estimate regional status and trends
  • present the estimates of regional trends
  • present the estimates of regional status


Summary of individual time series results

A time series of PBDE concentrations is assessed for status if:

  • there is at least one year with data in the period 2015 to 2020
  • there are at least three years of data over the whole time series
  • a parametric model can be fitted to the data and used to estimate the mean concentration in the final monitoring year (or, occasionally, if a non-parametric test of status is applied)

The conditions are more stringent for trends. Specifically, a time series is assessed for trends if:

  • there is at least one year with data in the period 2015 to 2020
  • there are at least five years of data over the whole time series
  • a parametric model can be fitted to the data and used to estimate the trend in mean concentration

Note that all trend assessments for individual time series and most status assessments are based on the fit of a parametric model. This is important because only the parametric results are passed into the regional assessments in the following sections. 463 of the 1785 PBDE time series were assessed for status using a non-parametric test.

The first tab below shows all the monitoring stations where there are individual time series assessments of trend or status for PBDEs. The purple circles are stations where there is a trend assessment for at least one PBDE, and the light blue cirles are stations where there are only status assessments.

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

  • blue: the mean concentration is significantly (p < 0.05) below the Background Assessment Concentration (BAC)
  • green: the mean concentration is significantly (p < 0.05) below the Federal Environmental Quality Guideline (FEQG)
  • orange: there is no FEQG and the mean concentration is not significantly below the BAC
  • red: the mean concentration is not signficantly below the FEQG
  • 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 final 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 blue, green, orange or red status in each MIME and OSPAR region
  • the same information presented as proportions

Note that there are no FEQGs for BDE66, BDE85, BD126, BD183, BD209.


Stations


BDE28


BDE47


BDE66


BDE85


BDE99


BD100


BD126


BD153


BD154


BD183


BD209


Trend summary (numbers)

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

OSPAR region MIME region status BDE28 BDE47 BDE66 BDE85 BDE99 BD100 BD126 BD153 BD154 BD183 total
1 Barents Sea upward trend 0 0 0 0 0 0 0 0 1 0 1
no trend 1 2 0 0 2 2 1 1 1 0 10
downward trend 1 2 0 0 1 2 0 1 0 0 7
Greenland-Scotland ridge upward trend 0 0 0 0 0 0 0 0 0 0 0
no trend 0 3 0 0 0 1 0 0 0 0 4
downward trend 0 1 0 0 0 1 0 0 0 0 2
Norwegian Sea upward trend 0 0 0 0 0 0 0 0 0 0 0
no trend 1 2 0 0 2 1 0 1 0 1 8
downward trend 1 1 0 0 1 2 0 0 2 0 7
total upward trend 0 0 0 0 0 0 0 0 1 0 1
no trend 2 7 0 0 4 4 1 2 1 1 22
downward trend 2 4 0 0 2 5 0 1 2 0 16
2 Norwegian Trench upward trend 0 0 0 0 0 1 0 0 0 0 1
no trend 2 3 0 0 3 1 0 3 3 0 15
downward trend 3 2 0 0 2 3 0 0 0 0 10
Northern North Sea upward trend 0 0 0 0 0 0 0 0 0 0 0
no trend 1 7 0 0 1 4 0 0 1 0 14
downward trend 1 3 0 0 2 2 0 1 1 0 10
Skagerrak and Kattegat upward trend 0 0 0 0 1 0 0 1 0 0 2
no trend 1 8 0 0 7 8 0 5 2 0 31
downward trend 2 6 0 0 5 4 0 1 1 0 19
Southern North Sea upward trend 0 0 0 0 0 0 0 0 0 0 0
no trend 6 8 3 2 4 10 0 7 15 3 58
downward trend 4 10 0 0 5 7 0 2 0 0 28
Channel upward trend 0 1 0 0 1 0 0 0 0 0 2
no trend 16 17 0 0 17 18 0 17 19 0 104
downward trend 1 4 0 0 2 3 0 1 2 0 13
total upward trend 0 1 0 0 2 1 0 1 0 0 5
no trend 26 43 3 2 32 41 0 32 40 3 222
downward trend 11 25 0 0 16 19 0 5 4 0 80
3 Irish and Scottish West Coast upward trend 0 0 0 0 0 0 0 0 0 0 0
no trend 2 7 0 0 10 8 0 1 2 0 30
downward trend 1 10 0 0 3 2 0 0 0 0 16
Irish Sea upward trend 0 0 0 0 0 0 0 0 0 0 0
no trend 1 7 1 0 8 6 0 6 5 0 34
downward trend 6 22 4 0 15 20 0 11 12 0 90
Celtic Sea upward trend 1 0 0 0 1 0 0 0 2 0 4
no trend 6 8 0 0 9 9 0 3 7 0 42
downward trend 0 8 1 0 5 5 0 2 1 1 23
total upward trend 1 0 0 0 1 0 0 0 2 0 4
no trend 9 22 1 0 27 23 0 10 14 0 106
downward trend 7 40 5 0 23 27 0 13 13 1 129
4 Northern Bay of Biscay upward trend 1 0 0 0 0 0 0 0 0 0 1
no trend 22 23 0 0 23 23 0 20 22 0 133
downward trend 0 0 0 0 0 0 0 1 1 0 2
Iberian Sea upward trend 0 4 0 0 0 0 0 0 2 0 6
no trend 1 17 19 1 14 18 0 16 19 0 105
downward trend 0 3 0 0 10 6 0 1 0 1 21
total upward trend 1 4 0 0 0 0 0 0 2 0 7
no trend 23 40 19 1 37 41 0 36 41 0 238
downward trend 0 3 0 0 10 6 0 2 1 1 23


Trend summary (proportions)

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

OSPAR region MIME region status BDE28 BDE47 BDE66 BDE85 BDE99 BD100 BD126 BD153 BD154 BD183 total
1 Barents Sea upward trend 0 0 0 0 0 0 50 5
no trend 50 50 67 50 100 50 50 56
downward trend 50 50 33 50 0 50 0 39
Greenland-Scotland ridge upward trend 0 0 0
no trend 75 50 67
downward trend 25 50 33
Norwegian Sea upward trend 0 0 0 0 0 0 0 0
no trend 50 67 67 33 100 0 100 53
downward trend 50 33 33 67 0 100 0 47
total upward trend 0 0 0 0 0 0 25 0 3
no trend 50 64 67 44 100 67 25 100 56
downward trend 50 36 33 56 0 33 50 0 41
2 Norwegian Trench upward trend 0 0 0 20 0 0 4
no trend 40 60 60 20 100 100 58
downward trend 60 40 40 60 0 0 38
Northern North Sea upward trend 0 0 0 0 0 0 0
no trend 50 70 33 67 0 50 58
downward trend 50 30 67 33 100 50 42
Skagerrak and Kattegat upward trend 0 0 8 0 14 0 4
no trend 33 57 54 67 72 67 60
downward trend 67 43 38 33 14 33 36
Southern North Sea upward trend 0 0 0 0 0 0 0 0 0 0
no trend 60 44 100 100 44 59 78 100 100 67
downward trend 40 56 0 0 56 41 22 0 0 33
Channel upward trend 0 5 5 0 0 0 2
no trend 94 77 85 86 94 90 87
downward trend 6 18 10 14 6 10 11
total upward trend 0 2 0 0 4 2 3 0 0 2
no trend 70 62 100 100 64 67 84 91 100 72
downward trend 30 36 0 0 32 31 13 9 0 26
3 Irish and Scottish West Coast upward trend 0 0 0 0 0 0 0
no trend 67 41 77 80 100 100 65
downward trend 33 59 23 20 0 0 35
Irish Sea upward trend 0 0 0 0 0 0 0 0
no trend 14 24 20 35 23 35 29 27
downward trend 86 76 80 65 77 65 71 73
Celtic Sea upward trend 14 0 0 7 0 0 20 0 6
no trend 86 50 0 60 64 60 70 0 61
downward trend 0 50 100 33 36 40 10 100 33
total upward trend 6 0 0 2 0 0 7 0 2
no trend 53 35 17 53 46 43 48 0 44
downward trend 41 65 83 45 54 57 45 100 54
4 Northern Bay of Biscay upward trend 4 0 0 0 0 0 1
no trend 96 100 100 100 95 96 98
downward trend 0 0 0 0 5 4 1
Iberian Sea upward trend 0 17 0 0 0 0 0 10 0 4
no trend 100 71 100 100 58 75 94 90 0 80
downward trend 0 12 0 0 42 25 6 0 100 16
total upward trend 4 9 0 0 0 0 0 5 0 3
no trend 96 85 100 100 79 87 95 93 0 89
downward trend 0 6 0 0 21 13 5 2 100 8


Status summary (numbers)

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

OSPAR region MIME region status BDE28 BDE47 BDE66 BDE85 BDE99 BD100 BD126 BD153 BD154 BD183 BD209 total
1 Barents Sea blue 0 0 0 0 0 0 0 2 0 0 0 2
green 6 6 0 0 5 6 0 3 6 0 0 32
orange 0 0 0 0 0 0 4 0 0 4 5 13
red 0 0 0 0 0 0 0 0 0 0 0 0
Greenland-Scotland ridge blue 0 0 0 0 0 0 0 0 0 0 0 0
green 0 9 0 0 9 9 0 0 0 0 0 27
orange 0 0 0 0 0 0 0 0 0 0 0 0
red 0 0 0 0 0 0 0 0 0 0 0 0
Norwegian Sea blue 0 0 0 0 0 0 0 0 0 1 0 1
green 4 4 0 0 4 4 0 3 4 0 0 23
orange 0 0 0 0 0 0 4 0 0 2 4 10
red 0 0 0 0 0 0 0 0 0 0 0 0
total blue 0 0 0 0 0 0 0 2 0 1 0 3
green 10 19 0 0 18 19 0 6 10 0 0 82
orange 0 0 0 0 0 0 8 0 0 6 9 23
red 0 0 0 0 0 0 0 0 0 0 0 0
2 Norwegian Trench blue 0 0 0 0 0 0 0 0 0 0 0 0
green 5 5 0 0 5 4 0 5 5 0 0 29
orange 0 0 0 0 0 0 5 0 0 5 5 15
red 0 0 0 0 0 1 0 0 0 0 0 1
Northern North Sea blue 0 0 0 0 0 0 0 0 0 0 0 0
green 11 13 0 0 12 12 0 11 10 0 0 69
orange 0 0 10 3 0 0 0 0 0 3 0 16
red 0 0 0 0 0 1 0 0 1 0 0 2
Skagerrak and Kattegat blue 0 0 0 0 0 0 0 0 0 0 0 0
green 11 17 0 0 15 15 0 13 12 0 0 83
orange 0 0 0 0 0 0 7 0 0 8 9 24
red 0 0 0 0 0 0 0 0 0 0 0 0
Southern North Sea blue 0 0 0 0 0 0 0 0 0 0 0 0
green 28 32 0 0 24 23 0 28 30 0 0 165
orange 0 0 28 20 0 0 0 0 0 20 11 79
red 0 0 0 0 7 8 0 0 1 0 0 16
Channel blue 5 0 0 0 0 0 0 1 0 0 0 6
green 21 26 0 0 26 26 0 24 25 0 0 148
orange 0 0 3 0 0 0 0 0 0 0 0 3
red 0 0 0 0 0 0 0 0 0 0 0 0
total blue 5 0 0 0 0 0 0 1 0 0 0 6
green 76 93 0 0 82 80 0 81 82 0 0 494
orange 0 0 41 23 0 0 12 0 0 36 25 137
red 0 0 0 0 7 10 0 0 2 0 0 19
3 Irish and Scottish West Coast blue 0 0 0 0 0 0 0 0 0 0 0 0
green 27 28 0 0 24 25 0 23 26 0 0 153
orange 0 0 2 1 0 0 0 0 0 22 0 25
red 0 0 0 0 3 2 0 0 1 0 0 6
Irish Sea blue 0 0 0 0 0 0 0 0 0 0 0 0
green 31 35 0 0 31 28 0 31 32 0 0 188
orange 0 0 18 2 0 0 0 0 0 10 0 30
red 1 0 0 0 2 6 0 0 0 0 0 9
Celtic Sea blue 8 0 0 0 0 0 0 6 0 0 0 14
green 21 29 0 0 28 29 0 21 29 0 0 157
orange 0 0 2 0 0 0 0 0 0 10 0 12
red 0 0 0 0 1 0 0 1 0 0 0 2
total blue 8 0 0 0 0 0 0 6 0 0 0 14
green 79 92 0 0 83 82 0 75 87 0 0 498
orange 0 0 22 3 0 0 0 0 0 42 0 67
red 1 0 0 0 6 8 0 1 1 0 0 17
4 Northern Bay of Biscay blue 10 0 0 0 0 0 0 17 0 0 0 27
green 22 32 0 0 32 32 0 15 32 0 0 165
orange 0 0 0 0 0 0 0 0 0 0 0 0
red 0 0 0 0 0 0 0 0 0 0 0 0
Iberian Sea blue 0 0 0 0 0 0 0 0 0 0 0 0
green 24 24 0 0 24 24 0 24 24 0 0 144
orange 0 0 23 23 0 0 0 0 0 23 0 69
red 0 0 0 0 0 0 0 0 0 0 0 0
total blue 10 0 0 0 0 0 0 17 0 0 0 27
green 46 56 0 0 56 56 0 39 56 0 0 309
orange 0 0 23 23 0 0 0 0 0 23 0 69
red 0 0 0 0 0 0 0 0 0 0 0 0


Status summary (proportions)

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

OSPAR region MIME region status BDE28 BDE47 BDE66 BDE85 BDE99 BD100 BD126 BD153 BD154 BD183 BD209 total
1 Barents Sea blue 0 0 0 0 0 40 0 0 0 4
green 100 100 100 100 0 60 100 0 0 68
orange 0 0 0 0 100 0 0 100 100 28
red 0 0 0 0 0 0 0 0 0 0
Greenland-Scotland ridge blue 0 0 0 0
green 100 100 100 100
orange 0 0 0 0
red 0 0 0 0
Norwegian Sea blue 0 0 0 0 0 0 0 33 0 3
green 100 100 100 100 0 100 100 0 0 68
orange 0 0 0 0 100 0 0 67 100 29
red 0 0 0 0 0 0 0 0 0 0
total blue 0 0 0 0 0 25 0 14 0 3
green 100 100 100 100 0 75 100 0 0 76
orange 0 0 0 0 100 0 0 86 100 21
red 0 0 0 0 0 0 0 0 0 0
2 Norwegian Trench blue 0 0 0 0 0 0 0 0 0 0
green 100 100 100 80 0 100 100 0 0 65
orange 0 0 0 0 100 0 0 100 100 33
red 0 0 0 20 0 0 0 0 0 2
Northern North Sea blue 0 0 0 0 0 0 0 0 0 0
green 100 100 0 0 100 92 100 91 0 79
orange 0 0 100 100 0 0 0 0 100 19
red 0 0 0 0 0 8 0 9 0 2
Skagerrak and Kattegat blue 0 0 0 0 0 0 0 0 0 0
green 100 100 100 100 0 100 100 0 0 78
orange 0 0 0 0 100 0 0 100 100 22
red 0 0 0 0 0 0 0 0 0 0
Southern North Sea blue 0 0 0 0 0 0 0 0 0 0 0
green 100 100 0 0 77 74 100 97 0 0 64
orange 0 0 100 100 0 0 0 0 100 100 30
red 0 0 0 0 23 26 0 3 0 0 6
Channel blue 19 0 0 0 0 4 0 4
green 81 100 0 100 100 96 100 94
orange 0 0 100 0 0 0 0 2
red 0 0 0 0 0 0 0 0
total blue 6 0 0 0 0 0 0 1 0 0 0 1
green 94 100 0 0 92 89 0 99 98 0 0 75
orange 0 0 100 100 0 0 100 0 0 100 100 21
red 0 0 0 0 8 11 0 0 2 0 0 3
3 Irish and Scottish West Coast blue 0 0 0 0 0 0 0 0 0 0
green 100 100 0 0 89 93 100 96 0 83
orange 0 0 100 100 0 0 0 0 100 14
red 0 0 0 0 11 7 0 4 0 3
Irish Sea blue 0 0 0 0 0 0 0 0 0 0
green 97 100 0 0 94 82 100 100 0 83
orange 0 0 100 100 0 0 0 0 100 13
red 3 0 0 0 6 18 0 0 0 4
Celtic Sea blue 28 0 0 0 0 21 0 0 8
green 72 100 0 97 100 75 100 0 85
orange 0 0 100 0 0 0 0 100 6
red 0 0 0 3 0 4 0 0 1
total blue 9 0 0 0 0 0 7 0 0 2
green 90 100 0 0 93 91 92 99 0 84
orange 0 0 100 100 0 0 0 0 100 11
red 1 0 0 0 7 9 1 1 0 3
4 Northern Bay of Biscay blue 31 0 0 0 53 0 14
green 69 100 100 100 47 100 86
orange 0 0 0 0 0 0 0
red 0 0 0 0 0 0 0
Iberian Sea blue 0 0 0 0 0 0 0 0 0 0
green 100 100 0 0 100 100 100 100 0 68
orange 0 0 100 100 0 0 0 0 100 32
red 0 0 0 0 0 0 0 0 0 0
total blue 18 0 0 0 0 0 30 0 0 7
green 82 100 0 0 100 100 70 100 0 76
orange 0 0 100 100 0 0 0 0 100 17
red 0 0 0 0 0 0 0 0 0 0


Regional assessment - methods

Tabulating the number of time series with each status category by region provides a quick summary of the individual time series results. However, it does not provide an objective regional assessment of status. Similarly, tabulating the number of time series with an upward or downward trend does not provide an objective regional assessment of trend. This section describes how the individual time series results can by synthesised in a meta-analysis to assess both status and trend at the regional level.

Trends

For a regional trend assessment, the trend in each time series is summarised by the estimated change in log concentration over the last twenty years (or shorter if the time series doesn’t extend that far back). Regional trends are then estimated by fitting the following linear mixed model by restricted maximum likelihood:

  • response: trend (yearly change in log concentration)
  • fixed model: region
  • random model: PBDE + region.PBDE + station + station.PBDE + trend estimation variation + residual variation

The fixed model means that a trend is estimated for each region. Trends in the different PBDEs are assumed to be broadly similar, because inputs and control measures are likely to affect all PBDEs in a similar way. Each regional trend can thus be interpreted as the common trend in PBDE concentrations in that region (i.e. the trend averaged across all PBDEs).

The random model has six terms:

  • PBDE allows for variation in trend between PBDEs common to all regions
  • region.PBDE allows for additional variation in trend between PBDEs within regions
  • station allows for variation in trend between stations common to all PBDEs
  • station.PBDE allows for additional variation in trend between stations and PBDEs common to all tissues and species within stations
  • trend estimation variation is the variance of the trend estimates from the individual time series analysis, assumed known and fixed
  • residual variation is the variation that cannot be explained by any of the fixed effects or the other random effects

The meta-analysis is restricted to time series from monitoring stations that are classified as ‘representative’ or ‘baseline’ (near pristine conditions or only subject to very diffuse inputs). ‘Impacted’ stations (those close to a point source) are omitted because trends there will likely reflect changes due to the point source and will be ‘unrepresentative’ at the regional level.

The meta-analysis is further restricted to:

  • regions with at least three trend stations with good geographic spread. Three stations is considered the minimum required to provide some sort of evidence base at the regional level
  • PBDEs with trend information for at least three stations (over all regions): PBDEs are treated as random effects in the meta-anlaysis, so information about trends in one PBDE can be ‘borrowed’ from the trend information in the other PBDEs

Status

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 assessment concentration. This ensures that status is always measured on the same scale, even though the assessment concentration might vary between PBDEs and species. Essentially the same linear mixed model as for trends is then fitted:

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

where status estimation variation is the variation in the status estimates from the individual time series analysis, assumed known and fixed.

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.

Again, the meta-analysis is restricted to regions with at least three status stations with good geographic spread and to PBDEs with status information for at least three stations (over all regions).

Presentation

The results of both the trend and status regional assessments are back-transformed for presentation. The estimated regional trend is then interpreted as the percentage yearly change in concentration and the estimated regional status as the ratio of the mean regional concentration to the assessment concentration. To illustrate the latter, 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 trend and status assessments for each OSPAR region in turn, having excluded trend assessments at baseline and impacted stations. The purple circles are stations where there is a trend assessment for at least one PBDE, and the light blue cirles are stations where there are only status assessments.

The following regions have an insufficient number or time series or spread of stations and are excluded from the regional assessment:

  • trend: Barents Sea, Norwegian Sea, Norwegian Trench
  • status: Norwegian Sea


OSPAR region 1


OSPAR region 2


OSPAR region 3


OSPAR region 4


Regional trends

The first 4 tabs show:

  • Regional trends: estimates of the regional trend (averaged over PBDEs) with pointwise 95% confidence intervals
  • Regional trends by PBDE: regional trend estimates for each PBDE with pointwise 95% confidence intervals plotted by PBDE
  • Regional trends by region: regional trend estimates for each PBDE with pointwise 95% confidence intervals plotted by region
  • Individual time series: the trend 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 these plots have the following interpretation:

  • downward triangle: the mean concentration is significantly decreasing (p < 0.05)
  • circle: there is no significant change in mean concentration (p > 0.05)
  • upward triangle: the mean concentration is significantly increasing (p < 0.05)

The final 2 tabs show the estimates of the regional trend (averaged over PBDEs) and the regional trend by PBDE


Regional trends


Regional trends by PBDE


Regional trends by region


Individual time series


Estimates by region

This table shows the estimates of the regional trend:

  • trend: the estimated mean yearly change in log concentration across the region (multiplied by 100 for presentation)
  • se: the corresponding standard error
  • lower, upper: the corresponding pointwise 95% confidence limits
  • % yearly change: the estimated mean % yearly change in concentration across the region
  • %yc lower, %yc upper: the corresponding pointwise 95% confidence limits


MIME region trend se lower upper % yearly change %yc lower %yc upper
Greenland-Scotland ridge -6.66 4.53 -15.53 2.21 -6.44 -14.38 2.24
Northern North Sea -8.55 2.96 -14.34 -2.75 -8.19 -13.36 -2.71
Skagerrak and Kattegat -1.98 2.64 -7.15 3.19 -1.96 -6.90 3.24
Southern North Sea -6.46 2.17 -10.72 -2.19 -6.25 -10.16 -2.17
Channel -3.27 2.11 -7.41 0.87 -3.22 -7.14 0.88
Irish and Scottish West Coast -9.10 2.56 -14.12 -4.09 -8.70 -13.17 -4.00
Irish Sea -13.03 1.94 -16.83 -9.23 -12.22 -15.49 -8.82
Celtic Sea -3.01 2.36 -7.64 1.62 -2.96 -7.35 1.63
Northern Bay of Biscay -4.95 2.23 -9.31 -0.59 -4.83 -8.89 -0.58
Iberian Sea -3.27 2.01 -7.20 0.67 -3.21 -6.95 0.67


Estimates by region and PBDE

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

  • trend: the estimated mean yearly change in log concentration across the region (multiplied by 100 for presentation)
  • se: the corresponding standard error
  • lower, upper: the corresponding pointwise 95% confidence limits
  • % yearly change: the estimated mean % yearly change in concentration across the region
  • %yc lower, %yc upper: the corresponding pointwise 95% confidence limits


MIME region PBDE trend se lower upper % yearly change %yc lower %yc upper
Greenland-Scotland ridge BDE47 -6.18 3.70 -13.43 1.06 -6.00 -12.57 1.07
BD100 -7.99 4.51 -16.82 0.84 -7.68 -15.48 0.85
Northern North Sea BDE28 -5.06 3.33 -11.59 1.47 -4.93 -10.94 1.48
BDE47 -6.41 2.46 -11.24 -1.59 -6.21 -10.63 -1.57
BDE99 -11.72 3.29 -18.17 -5.27 -11.06 -16.61 -5.14
BD100 -7.19 2.86 -12.79 -1.59 -6.94 -12.01 -1.58
BD153 -10.12 4.01 -17.97 -2.27 -9.62 -16.45 -2.24
BD154 -10.37 3.71 -17.64 -3.10 -9.85 -16.17 -3.05
Skagerrak and Kattegat BDE28 -4.02 3.98 -11.83 3.79 -3.94 -11.16 3.86
BDE47 -5.68 2.16 -9.92 -1.44 -5.52 -9.44 -1.43
BDE99 -4.22 2.25 -8.64 0.20 -4.13 -8.27 0.20
BD100 -0.61 2.25 -5.02 3.80 -0.61 -4.89 3.87
BD153 1.43 2.72 -3.89 6.75 1.44 -3.82 6.99
BD154 1.64 3.92 -6.03 9.32 1.66 -5.85 9.77
Southern North Sea BDE28 -10.35 2.21 -14.68 -6.02 -9.83 -13.65 -5.84
BDE47 -7.75 1.79 -11.27 -4.24 -7.46 -10.66 -4.15
BDE66 -6.55 3.89 -14.18 1.08 -6.34 -13.22 1.08
BDE85 -1.77 3.36 -8.35 4.82 -1.75 -8.01 4.94
BDE99 -9.23 2.26 -13.66 -4.81 -8.82 -12.77 -4.69
BD100 -8.16 2.00 -12.08 -4.24 -7.84 -11.38 -4.15
BD153 -7.54 2.83 -13.08 -2.00 -7.26 -12.26 -1.98
BD154 -0.31 1.97 -4.18 3.55 -0.31 -4.09 3.61
BD183 -6.43 4.01 -14.29 1.43 -6.22 -13.32 1.45
Channel BDE28 -6.87 2.42 -11.62 -2.12 -6.64 -10.97 -2.10
BDE47 -5.32 1.87 -9.00 -1.65 -5.19 -8.60 -1.64
BDE99 -1.35 2.20 -5.66 2.97 -1.34 -5.50 3.02
BD100 -3.35 2.02 -7.31 0.61 -3.30 -7.05 0.61
BD153 1.29 2.40 -3.41 5.98 1.29 -3.35 6.17
BD154 -3.60 2.04 -7.60 0.40 -3.54 -7.32 0.40
Irish and Scottish West Coast BDE28 -6.48 3.56 -13.45 0.49 -6.28 -12.59 0.49
BDE47 -12.87 2.00 -16.79 -8.94 -12.07 -15.46 -8.55
BDE99 -9.66 2.32 -14.20 -5.13 -9.21 -13.24 -5.00
BD100 -10.40 2.47 -15.24 -5.55 -9.87 -14.14 -5.40
BD153 -6.47 3.94 -14.18 1.25 -6.26 -13.22 1.26
BD154 -8.35 3.89 -15.97 -0.72 -8.01 -14.76 -0.72
Irish Sea BDE28 -11.63 2.05 -15.64 -7.62 -10.98 -14.48 -7.34
BDE47 -13.81 1.40 -16.56 -11.06 -12.90 -15.26 -10.47
BDE66 -16.39 2.48 -21.25 -11.52 -15.11 -19.14 -10.89
BDE99 -14.11 1.61 -17.26 -10.96 -13.16 -15.85 -10.38
BD100 -14.17 1.48 -17.07 -11.27 -13.21 -15.69 -10.66
BD153 -11.42 1.75 -14.84 -8.00 -10.79 -13.79 -7.69
BD154 -9.96 1.63 -13.15 -6.76 -9.48 -12.33 -6.54
Celtic Sea BDE28 -3.36 3.62 -10.45 3.73 -3.30 -9.92 3.80
BDE47 -6.06 2.01 -10.00 -2.12 -5.88 -9.52 -2.09
BDE66 -4.72 3.27 -11.13 1.69 -4.61 -10.54 1.71
BDE99 -1.60 2.20 -5.91 2.71 -1.59 -5.74 2.75
BD100 -5.54 2.28 -10.01 -1.07 -5.39 -9.53 -1.07
BD153 -2.94 3.77 -10.32 4.44 -2.90 -9.81 4.54
BD154 2.88 2.67 -2.36 8.12 2.92 -2.33 8.46
Northern Bay of Biscay BDE28 -2.01 2.60 -7.11 3.09 -1.99 -6.86 3.14
BDE47 -5.47 2.56 -10.49 -0.45 -5.32 -9.96 -0.45
BDE99 -4.68 2.58 -9.74 0.38 -4.57 -9.28 0.38
BD100 -4.70 2.55 -9.70 0.31 -4.59 -9.25 0.31
BD153 -5.24 2.69 -10.51 0.03 -5.11 -9.98 0.03
BD154 -7.19 2.57 -12.24 -2.15 -6.94 -11.52 -2.13
Iberian Sea BDE28 -4.23 3.99 -12.05 3.60 -4.14 -11.35 3.66
BDE47 1.81 1.59 -1.32 4.93 1.82 -1.31 5.06
BDE66 -6.29 2.19 -10.59 -1.99 -6.09 -10.04 -1.97
BDE85 -3.15 4.12 -11.22 4.92 -3.10 -10.61 5.05
BDE99 -8.96 1.61 -12.11 -5.81 -8.57 -11.41 -5.64
BD100 -6.08 1.67 -9.35 -2.81 -5.90 -8.93 -2.77
BD153 -0.41 2.52 -5.36 4.54 -0.41 -5.21 4.64
BD154 3.23 2.11 -0.91 7.36 3.28 -0.91 7.64
BD183 -5.32 3.89 -12.95 2.31 -5.18 -12.14 2.33


Regional status compared to the Federal Environmental Quality Guideline (FEQG)

The first 4 tabs show:

  • Regional status: estimates of the regional status (averaged over PBDEs) with pointwise upper one-sided 95% confidence intervals
  • Regional status by PBDE: regional status estimates for each PBDE with pointwise upper one-sided 95% confidence intervals plotted by PBDE
  • Regional status by region: regional status estimates for each PBDE 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:

  • blue: the mean concentration is significantly (p < 0.05) below the Background Assessment Concentration (BAC)
  • green: the mean concentration is significantly (p < 0.05) below the FEQG
  • red: the mean concentration is not significantly below the FEQG

Note that to see why some points might be coloured blue, it is necessary to look ahead to the next section, where status is compared to the BAC. Unfortunately, it isn’t easy to present the assessment of status relative to the FEQG with the assessment of status relative to the BAC because the ratio of the BAC to the FEQG can vary between PBDEs and species.

The final 2 tabs show the estimates of the regional status (averaged over PBDEs) and the regional status trend by PBDE


Regional status


Regional status by PBDE


Regional status by region


Individual time series


Estimates by region

This table shows the estimates of the regional status:

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


MIME region status se upper concentration conc upper
Barents Sea -5.74 1.05 -4.01 0.00 0.02
Greenland-Scotland ridge -5.63 1.09 -3.84 0.00 0.02
Norwegian Trench -4.81 1.06 -3.07 0.01 0.05
Northern North Sea -4.73 1.04 -3.03 0.01 0.05
Skagerrak and Kattegat -5.54 1.03 -3.85 0.00 0.02
Southern North Sea -4.98 1.02 -3.29 0.01 0.04
Channel -6.00 1.02 -4.32 0.00 0.01
Irish and Scottish West Coast -4.82 1.03 -3.13 0.01 0.04
Irish Sea -4.34 1.02 -2.66 0.01 0.07
Celtic Sea -5.77 1.02 -4.09 0.00 0.02
Northern Bay of Biscay -6.57 1.02 -4.89 0.00 0.01
Iberian Sea -5.19 1.02 -3.51 0.01 0.03


Estimates by region and PBDE

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

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


MIME region PBDE status se upper concentration conc upper
Barents Sea BDE28 -9.51 0.37 -8.90 0.00 0.00
BDE47 -5.51 0.34 -4.95 0.00 0.01
BDE99 -3.61 0.36 -3.03 0.03 0.05
BD100 -3.07 0.34 -2.51 0.05 0.08
BD126
BD153 -7.48 0.40 -6.83 0.00 0.00
BD154 -5.27 0.35 -4.69 0.01 0.01
BD209
Greenland-Scotland ridge BDE47 -5.82 0.37 -5.21 0.00 0.01
BDE99 -3.09 0.46 -2.34 0.05 0.10
BD100 -3.32 0.42 -2.62 0.04 0.07
Norwegian Trench BDE28 -9.03 0.37 -8.42 0.00 0.00
BDE47 -4.50 0.37 -3.88 0.01 0.02
BDE99 -2.95 0.38 -2.33 0.05 0.10
BD100 -1.95 0.37 -1.35 0.14 0.26
BD126
BD153 -6.07 0.38 -5.45 0.00 0.00
BD154 -4.36 0.37 -3.75 0.01 0.02
BD183
BD209
Northern North Sea BDE28 -8.65 0.34 -8.09 0.00 0.00
BDE47 -4.64 0.25 -4.23 0.01 0.01
BDE66
BDE99 -3.33 0.32 -2.80 0.04 0.06
BD100 -2.45 0.27 -2.01 0.09 0.13
BD153 -5.18 0.36 -4.59 0.01 0.01
BD154 -4.15 0.34 -3.60 0.02 0.03
Skagerrak and Kattegat BDE28 -9.58 0.25 -9.17 0.00 0.00
BDE47 -5.63 0.22 -5.28 0.00 0.01
BDE99 -3.38 0.22 -3.01 0.03 0.05
BD100 -2.88 0.22 -2.52 0.06 0.08
BD126
BD153 -6.79 0.26 -6.35 0.00 0.00
BD154 -4.99 0.25 -4.58 0.01 0.01
BD209
Southern North Sea BDE28 -9.13 0.23 -8.75 0.00 0.00
BDE47 -5.12 0.18 -4.83 0.01 0.01
BDE66
BDE85
BDE99 -3.29 0.20 -2.97 0.04 0.05
BD100 -2.63 0.20 -2.30 0.07 0.10
BD153 -5.43 0.24 -5.04 0.00 0.01
BD154 -4.25 0.20 -3.93 0.01 0.02
BD183
BD209
Channel BDE28 -10.54 0.18 -10.25 0.00 0.00
BDE47 -6.21 0.17 -5.93 0.00 0.00
BDE66
BDE99 -3.26 0.18 -2.97 0.04 0.05
BD100 -3.44 0.17 -3.15 0.03 0.04
BD153 -6.57 0.18 -6.28 0.00 0.00
BD154 -5.98 0.17 -5.69 0.00 0.00
Irish and Scottish West Coast BDE28 -8.55 0.24 -8.15 0.00 0.00
BDE47 -5.37 0.18 -5.06 0.00 0.01
BDE99 -2.33 0.20 -2.00 0.10 0.13
BD100 -2.41 0.21 -2.05 0.09 0.13
BD153 -5.42 0.39 -4.77 0.00 0.01
BD154 -4.83 0.26 -4.41 0.01 0.01
BD183
Irish Sea BDE28 -8.70 0.19 -8.39 0.00 0.00
BDE47 -4.53 0.15 -4.28 0.01 0.01
BDE66
BDE99 -2.60 0.16 -2.33 0.07 0.10
BD100 -1.89 0.16 -1.63 0.15 0.20
BD153 -4.92 0.19 -4.61 0.01 0.01
BD154 -3.41 0.17 -3.13 0.03 0.04
Celtic Sea BDE28 -10.10 0.19 -9.80 0.00 0.00
BDE47 -5.96 0.17 -5.69 0.00 0.00
BDE66
BDE99 -3.00 0.17 -2.73 0.05 0.07
BD100 -3.35 0.17 -3.07 0.03 0.05
BD153 -6.67 0.19 -6.35 0.00 0.00
BD154 -5.54 0.18 -5.24 0.00 0.01
BD183
Northern Bay of Biscay BDE28 -10.92 0.16 -10.67 0.00 0.00
BDE47 -6.62 0.15 -6.37 0.00 0.00
BDE99 -3.80 0.16 -3.55 0.02 0.03
BD100 -4.02 0.15 -3.77 0.02 0.02
BD153 -7.79 0.16 -7.53 0.00 0.00
BD154 -6.26 0.15 -6.01 0.00 0.00
Iberian Sea BDE28 -10.10 0.31 -9.60 0.00 0.00
BDE47 -4.78 0.18 -4.49 0.01 0.01
BDE66
BDE85
BDE99 -2.35 0.18 -2.06 0.10 0.13
BD100 -3.14 0.18 -2.84 0.04 0.06
BD153 -5.74 0.20 -5.40 0.00 0.00
BD154 -5.04 0.19 -4.72 0.01 0.01
BD183


Regional status compared to the Background Assessment Concentration (BAC)

The first 4 tabs show:

  • Regional status: estimates of the regional status (averaged over PBDEs) with pointwise upper one-sided 95% confidence intervals
  • Regional status by PBDE: regional status estimates for each PBDE with pointwise upper one-sided 95% confidence intervals plotted by PBDE
  • Regional status by region: regional status estimates for each PBDE 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:

  • blue: the mean concentration is significantly (p < 0.05) below the BAC
  • green: the mean concentration is significantly (p < 0.05) below the Federal Environmental Quality Guideline (FEQG)
  • orange: there is no FEQG and the mean concentration is not significantly below the BAC
  • red: the mean concentration is not significantly below the FEQG

The final 2 tabs show the estimates of the regional status (averaged over PBDEs) and the regional status trend by PBDE


Regional status


Regional status by PBDE


Regional status by region


Individual time series


Estimates by region

This table shows the estimates of the regional status:

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


MIME region status se upper concentration conc upper
Barents Sea 1.54 0.53 2.41 4.67 11.13
Greenland-Scotland ridge 1.62 0.60 2.60 5.04 13.52
Norwegian Trench 2.41 0.53 3.28 11.08 26.61
Northern North Sea 2.51 0.50 3.33 12.28 27.80
Skagerrak and Kattegat 1.79 0.48 2.58 5.99 13.14
Southern North Sea 2.31 0.46 3.06 10.06 21.29
Channel 1.28 0.47 2.05 3.60 7.76
Irish and Scottish West Coast 2.45 0.48 3.23 11.54 25.36
Irish Sea 2.84 0.46 3.60 17.18 36.74
Celtic Sea 1.46 0.46 2.22 4.29 9.20
Northern Bay of Biscay 0.67 0.47 1.44 1.96 4.21
Iberian Sea 1.90 0.46 2.66 6.70 14.24


Estimates by region and PBDE

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

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


MIME region PBDE status se upper concentration conc upper
Barents Sea BDE28 1.02 0.37 1.63 2.77 5.09
BDE47 4.01 0.34 4.57 55.32 96.25
BDE99 2.13 0.35 2.71 8.38 14.98
BD100 2.67 0.34 3.22 14.43 25.09
BD126 -0.29 0.46 0.47 0.75 1.61
BD153 -0.37 0.39 0.27 0.69 1.31
BD154 1.86 0.35 2.43 6.40 11.37
BD209 3.45 0.66 4.53 31.58 93.01
Greenland-Scotland ridge BDE47 3.69 0.37 4.29 39.86 73.12
BDE99 2.66 0.46 3.41 14.23 30.17
BD100 2.41 0.42 3.10 11.14 22.18
Norwegian Trench BDE28 1.48 0.37 2.08 4.39 8.03
BDE47 5.01 0.37 5.62 150.01 275.32
BDE99 2.76 0.37 3.38 15.88 29.28
BD100 3.78 0.36 4.38 43.71 79.55
BD126 0.11 0.42 0.80 1.12 2.23
BD153 1.03 0.37 1.65 2.81 5.18
BD154 2.75 0.37 3.35 15.65 28.64
BD183 1.42 0.52 2.27 4.15 9.69
BD209 4.42 0.55 5.32 82.84 204.70
Northern North Sea BDE28 1.86 0.34 2.42 6.41 11.23
BDE47 4.87 0.25 5.28 130.45 196.55
BDE66 2.08 0.34 2.65 8.04 14.10
BDE99 2.40 0.32 2.92 10.98 18.47
BD100 3.28 0.27 3.72 26.60 41.36
BD153 1.94 0.35 2.53 6.98 12.49
BD154 2.97 0.33 3.52 19.42 33.63
Skagerrak and Kattegat BDE28 0.98 0.24 1.38 2.68 3.99
BDE47 3.90 0.21 4.25 49.21 69.85
BDE99 2.39 0.22 2.75 10.92 15.71
BD100 2.89 0.22 3.25 17.98 25.74
BD126 -0.31 0.37 0.30 0.73 1.35
BD153 0.38 0.26 0.80 1.46 2.23
BD154 2.17 0.25 2.58 8.76 13.15
BD209 4.07 0.54 4.96 58.56 142.98
Southern North Sea BDE28 1.39 0.22 1.76 4.03 5.82
BDE47 4.39 0.18 4.68 80.63 107.72
BDE66 1.64 0.24 2.03 5.13 7.59
BDE85 2.08 0.33 2.62 8.03 13.74
BDE99 2.44 0.20 2.76 11.45 15.79
BD100 3.11 0.20 3.44 22.33 31.14
BD153 1.71 0.24 2.10 5.52 8.13
BD154 2.87 0.19 3.19 17.66 24.24
BD183 1.66 0.34 2.22 5.27 9.17
BD209 3.81 0.37 4.41 45.01 82.63
Channel BDE28 -0.02 0.17 0.27 0.98 1.31
BDE47 3.30 0.17 3.58 27.12 35.78
BDE66 1.07 0.36 1.67 2.93 5.33
BDE99 2.48 0.17 2.77 11.94 15.90
BD100 2.29 0.17 2.58 9.91 13.15
BD153 0.55 0.17 0.83 1.73 2.30
BD154 1.14 0.17 1.42 3.12 4.14
Irish and Scottish West Coast BDE28 1.97 0.24 2.37 7.20 10.73
BDE47 4.14 0.18 4.44 63.04 85.13
BDE99 3.40 0.20 3.73 30.04 41.54
BD100 3.33 0.21 3.68 27.85 39.47
BD153 1.73 0.40 2.39 5.67 10.87
BD154 2.29 0.26 2.71 9.88 15.05
BD183 1.50 0.53 2.36 4.47 10.62
Irish Sea BDE28 1.81 0.19 2.12 6.12 8.35
BDE47 4.98 0.15 5.23 145.49 186.29
BDE66 2.07 0.20 2.40 7.96 11.03
BDE99 3.12 0.16 3.38 22.73 29.48
BD100 3.84 0.16 4.09 46.33 59.90
BD153 2.21 0.18 2.52 9.14 12.39
BD154 3.71 0.17 4.00 40.97 54.40
Celtic Sea BDE28 0.41 0.18 0.71 1.50 2.03
BDE47 3.55 0.16 3.82 34.72 45.52
BDE66 1.05 0.36 1.64 2.86 5.16
BDE99 2.73 0.16 3.00 15.26 20.01
BD100 2.37 0.17 2.65 10.73 14.15
BD153 0.45 0.19 0.76 1.57 2.13
BD154 1.58 0.18 1.87 4.85 6.51
BD183 0.35 0.47 1.12 1.42 3.06
Northern Bay of Biscay BDE28 -0.41 0.15 -0.15 0.67 0.86
BDE47 2.89 0.15 3.14 17.99 23.12
BDE99 1.93 0.15 2.18 6.88 8.85
BD100 1.71 0.15 1.96 5.52 7.10
BD153 -0.68 0.15 -0.42 0.51 0.66
BD154 0.86 0.15 1.11 2.35 3.03
Iberian Sea BDE28 0.32 0.30 0.82 1.38 2.28
BDE47 4.72 0.18 5.01 112.29 149.89
BDE66 1.79 0.20 2.12 5.98 8.32
BDE85 0.66 0.26 1.08 1.94 2.96
BDE99 3.37 0.18 3.66 29.14 38.90
BD100 2.58 0.18 2.87 13.19 17.71
BD153 1.37 0.20 1.70 3.95 5.48
BD154 2.06 0.19 2.38 7.86 10.75
BD183 0.37 0.28 0.83 1.45 2.29


PBDE profiles

The profile of concentrations across PBDEs can sometimes be useful for examining sources, and for comparing concentrations across regions where assessment criteria are not available. Profiles were examined by fitting the following linear mixed model by restricted maximum likelihood:

  • response: mean log concentration
  • fixed model: region
  • random model: PBDE + region.PBDE + station + station.PBDE + estimation variance + residual variation

where, for each time series, the mean log concentration is the estimated mean log concentration in the final monitoring year and the estimation variance is the variance associated with this estimate.

The estimated PBDE concentration profiles by region are shown below with pointwise 95% confidence limits. The units are ug/kg lw.