Hazardous substances in marine organisms

Indicator Specification
Indicator codes: CSI 049 , MAR 001
Created 07 Aug 2019 Published 21 Oct 2019 Last modified 04 Dec 2019
15 min read
This indicator describes the levels of and trends in the levels of eight hazardous substances in marine biota in European seas , based on individual assessments of monitoring data for the following substances: mercury (Hg) and its compounds; cadmium (Cd) and its compounds; lead (Pb) and its compounds; HCB; PCBs, using chlorinated biphenyls CB28, CB52, CB101, CB118, CB138, CB153 and CB180 as representatives; the pesticide DDT (using pp’DDE as a representative); the pesticide Lindane (1,2,3,4,5,6-hexachlorocyclohexane); the polyaromatic hydrocarbon BaP. The indicator is based on data on the levels of these substances measured in organisms from the regional seas as follows: Baltic Sea — Atlantic herring (Clupea harengus); North-East Atlantic Ocean — blue mussel (Mytilus app), Atlantic cod (Gadus morhua), flounder (Platichtys flesus); Mediterranean Sea — Mediterranean mussel (Mytilus galloprovinicialis); Black Sea — Mediterranean mussel (Mytilus galloprovinicialis).

Assessment versions

Published (reviewed and quality assured)

Rationale

Justification for indicator selection

Hazardous substances are widespread in the marine environment. Many can be found at low concentrations in the Earth's crust and occur naturally in seawater. Synthetic hazardous substances such as PCBs, DDT, polybrominated diphenyl ethers (PBDEs) and perfluorocarbons (PFCs) are not found naturally in the environment. The main sources are generally waste/disposal, the burning of fossil fuels and industrial activities, including mining and production. Human activities have caused a general mobilisation of these hazardous substances in the marine environment. The pathway of contamination is not always obvious, but it is primarily through riverine discharge and atmospheric deposition. Hence, although hot spots tend to be directly linked to particular human activities, the substances are also found in organisms that are collected far from point sources. 

The effects that some hazardous substances have on the environment and their potential risk to human health because of their toxic, bioaccumulative and persistent characteristics have led to considerable efforts (at the political, management and scientific levels) to address them. Specific policies and conventions aim to minimise the direct and indirect effects of these contaminants, generally by reducing emissions and discharges to the marine environment.

There is a large number of potentially hazardous substances, but, to date, data with sufficient geographical and temporal coverage are available for only a few, which is insufficient to warrant a pan-European assessment of hazardous substances in marine organisms. Therefore, this indicator is based on the assessment of eight substances: the metals cadmium, lead and mercury; the pesticides DDT and lindane; two other types of synthetic substance, HCB and PCBs; and as of the 2014 assessment the polycyclic aromatic hydrocarbon BaP. All eight contaminants are included in the lists of the Environmental Quality Standards Directive (EQSD), a 'daughter' directive of the Water Framework Directive (WFD). However, although their use has been severely restricted or banned, observations show that these substances are still present or accumulating in all of Europe’s seas, thus meriting continued monitoring.

Scientific references

Indicator definition

This indicator describes the levels of and trends in the levels of eight hazardous substances in marine biota in European seas, based on individual assessments of monitoring data for the following substances:

  • mercury (Hg) and its compounds;
  • cadmium (Cd) and its compounds;
  • lead (Pb) and its compounds;
  • HCB;
  • PCBs, using chlorinated biphenyls CB28, CB52, CB101, CB118, CB138, CB153 and CB180 as representatives;
  • the pesticide DDT (using pp’DDE as a representative);
  • the pesticide Lindane (1,2,3,4,5,6-hexachlorocyclohexane);
  • the polyaromatic hydrocarbon BaP.


The indicator is based on data on the levels of these substances measured in organisms from the regional seas as follows:

  • Baltic Sea — Atlantic herring (Clupea harengus);
  • North-East Atlantic Ocean — blue mussel (Mytilus app), Atlantic cod (Gadus morhua), flounder (Platichtys flesus);
  • Mediterranean Sea — Mediterranean mussel (Mytilus galloprovinicialis);
  • Black Sea — Mediterranean mussel (Mytilus galloprovinicialis).

Units

The classification in the maps is based on concentrations in µg/kg, which are then classified into one of three classes: green (low concentration), yellow (moderate concentration) or red (high concentration). In addition, a pie chart shows the percentage accounted for by each class within each of the four regional seas.

Policy context and targets

Context description

A range of EU, regional and national legislation has been implemented in Europe to address the use of chemicals and their emission to the environment, including to fresh and marine waters:

  • The regulation of chemical pollutants in water began with the Dangerous Substances Directive (76/464/EEC), which has been integrated into the WFD (2000/60/EC). It requires the establishment of a list of priority substances by 2021 and of EQSs for newly identified priority substances by the end of 2027
  • The chemical status of Europe's surface waters is currently addressed in accordance with the EQSD (2013/39/EU), a 'daughter' directive of the WFD, whose Annex II replaced the first list of priority substances set out in Decision No 2455/2001/EC. The EQSD defines EQSs for fresh and coastal waters for pollutants of EU-wide relevance, known as priority substances. Member States are required to take action with the view to meeting the quality standards set out in the objectives of the EQSD.
  • More recently, combating this type of pollution in the open sea has been address by the Marine Strategy Framework Directive (2008/56/EC), which requires the achievement or maintenance of GES in European seas by the year 2020 at the latest, through the adoption of national marine strategies based on 11 qualitative descriptors. Descriptor 8 ('Concentrations of contaminants are at levels not giving rise to pollution effects') and Descriptor 9 ('Contaminants in fish and other seafood for human consumption do not exceed levels established by Community legislation or other relevant standards') refer specifically to contaminants.

Complementing these efforts are the Basel, Rotterdam and Stockholm Conventions, which are multilateral environmental agreements that have the common objective of protecting human health and the environment from hazardous chemicals and wastes.

Targets

The aim of the WFD was to achieve zero, near-zero or background contaminant concentrations (more specifically defined in a daughter directive on environmental quality standards, i.e. the EQSD, 2008/105/EC), depending on the contaminant. This was to be achieved through abatement actions in relation to emmissions, with the objective of reaching good ecological and chemical status by 2015 for fresh, transitional and coastal waters. Goals similar to those of the WFD have also been outlined by OSPAR and the Baltic Marine Environment Protection Commission (Helcom). For the Mediterranean Sea, similar targets have been adopted. The reduction and phasing-out targets were formulated in accordance with related regional and international conventions and programmes, such as EU directives, policies and strategies, and the Stockholm and Basel Conventions. However, similar targets have yet to be formulated for the Black Sea, although discussions are under way.

Within the scope of the Marine Strategy Framework Directive, hazardous substances are the relevant criteria and indicators in marine waters under Descriptor 8 ('Concentrations of contaminants are at levels not giving rise to pollution effects') and Descriptor 9 ('Contaminants in fish and other seafood for human consumption do not exceed levels established by Community legislation or other relevant standards'). In this regard, Member States are required to take into account relevant existing environmental targets,  including the EQSs set out in the EQSD. Therefore, this directive applies to waters covered by both the WFD and the Marine Strategy Framework Directive, i.e. the seaward side of the baseline to the extent of territorial waters. A process is under way to define standards for the hazardous substances listed in biota, with a view to applying these to the marine and coastal environments.

Related policy documents

Key policy question

Are the concentrations of and trends in hazardous substances in marine organisms acceptable?

Specific policy question

Are the concentrations of the selected hazardous substances in marine organisms acceptable, and if not, are they decreasing?

Methodology

Methodology for indicator calculation

The two main sources of data for this indicator are ICES and EMODNet datasets. ICES data come from OSPAR and HELCOM contracting parties, and are therefore sub-samples of national data assembled for the purpose of providing comparable indicators of state and impact of transitional, coastal and marine waters (TCM-data) on a Europe-wide scale. In addition, data supplied by EMODnet were combined with the ICES data.

Geographical coverage

There is generally good data coverage for concentrations in the North-East Atlantic and in the Baltic; however, the Mediterranean Sea was represented only by data from France and Italy. An improvement in data reporting is needed to provide a better estimate of levels and trends for the Mediterranean Sea. For the Black Sea, the only available data were Romanian mussel data, and because of the requirement for conversion to preferred assessment basis (see more details in methodology link below), too few data were available for assessment. In general, the data for this sea region were not sufficient for analysis.  

Temporal coverage

Concentrations in biota were measured during the period from 1978 to 2017. However, the assessment only includes time series from 2008 onward and that cover at least 2 years, not necessarily contiguous. Trends were calculated for only time series with at least 5 years of data with at least one non-censored measurement (see more details in methodology link below); many of these series have gaps, with intervals of 2 or more years between observations.

Tissues

For fish, only concentrations from the following tissues were used:

  • for mercury, muscle was used;
  • for the other metals, liver was used;
  • for organic compounds, liver was used in all fish except herring (Clupea harengus), for which muscle was used.

Other samples were discarded. This is the same procedure as that followed by OSPAR.

More details on the methodology and limit concentrations used for classification can be found here.

Methodology for gap filling

The assessment method does not require that time series be complete, so no actions are taken to fill such gaps. Instead, the method adapts to gaps in the time series.

The regional assessments are based on tallies of results for a single time series within each region, without further consideration of geographical distribution within the region. Any gaps in the geographical coverage will mean that the regional assessment may not be representative of the region as a whole. No attempts are made to extrapolate results from available data to estimate conditions in geographical areas without data.

Methodology references

  • 1881/2006/EC Commission regulation Commission regulation (EC) No 1881/2006 of 19 December 2006 setting maximum levels for certain contaminants in foodstuffs.
  • E.C. 2003, technical document Technical guidance document in support of Commission Directive 93/67/EEC on risk assessment for new notified substances and Commission Regulation (EC) No 1488/94 on risk assessment for existing substances and Commission Directive (EC) 98/8 on biocides. European Commission
  • ICES, 2000. Report Of The Working Group on Statistical Aspects of Environmental Monitoring Nantes, France, 27- 31 March 2000 91 pp. ICES, 2000.
  • OSPAR 2008 Co-ordinated Environmental Monitoring Programme - Assessment manual for contaminants in sediment and biota. OSPAR Commission, 2008, publication no. 379/2008. ISBN 978-1-906840-20-4. 39 pp.
  • OSPAR 2009a Trends in waterborne inputs Assessment of riverine inputs and direct discharges of nutrents and selected hazardous substances to OSAPR maritime area in 1990-2006, OSPAR Commission, publication number 448/2009, 113 pp.. ISBN 978-1-906840-88-4
  • OSPAR 2009b CEMP: 2008/2009 Assessment of trends and concentrations of selected hazardous substances in sediments and biota. OSPAR Publication Number: 390/2009. ISBN 978-1-906840-30-3.

Data specifications

EEA data references

External data references

Data sources in latest figures

Uncertainties

Methodology uncertainty

Aggregated data do not necessarily convey the uncertainty problems. In addition, the time coverage is very variable between series and some of the trends shown may be based mainly on older data. The statistical significance of trends is based on a two-sided test with a nominal 5 % significance level, performed separately for each time series, without regard to serial correlation. A finding of 'No trend' (i.e. no statistically significant trend) may be due either to a lack of any real trend or to insufficient data (too few years in the data series or values in general being below the reporting limit).

Data sets uncertainty

This assessment is based on data reported to the EEA by EEA member countries. These data have significant gaps in terms of coverage (geographical and temporal) and consistency, especially for the Mediterranean and Black Seas. These data uncertainties, therefore, hinder a more comprehensive assessment of concentrations of and trends in hazardous substances in European marine waters. The assessment therefore does not necessarily convey the uncertainty these problems cause. It should also be noted that the three-class system used to classify the concentrations of hazardous substances (as green, yellow or red) does not necessarily highlight risks to human consumption.

Rationale uncertainty

The classification system reflects both observed levels of contaminants and the uncertainty in relation to the trends or levels indicated by the available data. Thus, a red classification does not necessarily mean that estimated levels are above the limit; it may merely indicate that the uncertainty is so large (because of lack of data and/or high variability in data) that it cannot be concluded with reasonable confidence that the true level is below the highest limit. It should also be noted that this three-class system for classifying concentrations of hazardous substances in fish does not highlight cases in which there is a risk to human consumption.

More generally, it should also be noted that considerable efforts have been made (i.e. at the policy, management and research levels) to establish and maintain monitoring programmes to assess the level and effect of and trends in hazardous substances in biota, and to select the most appropriate indicator tissues for particular species. However, there is a lack of reliable and consistent data for many hazardous substances and for several regions. Although basic legislation is in place to combat excessive exposure, specific assessment criteria with respect to levels, trends and effects need to be further developed for the indicator matrices. Furthermore, the measurement of concentrations in biota is not coordinated with measurements of inputs, which enhances the uncertainty in the correlation between the two.

It should also be noted that this indicator should not be used as an assessment of compliance monitoring in relation to the WFD, mainly because the monitoring strategy and assessment criteria used in this indicator measure the status of hazardous substances in biota, whereas the WFD EQSs concern concentrations in water for the most part. The exceptions include mercury and HCB in 'prey tissue', i.e. the whole individual, which would only apply to mussels in this indicator. There is a provision under the EQSD that allows Member States to establish other EQSs for biota (and sediment) for other substances as long as they provide the same level of protection. The ongoing development of technical guidance for deriving EQSs for the WFD should help Member States if they choose this solution. In addition to this, Member States will also have to take account of new legislation, for example technical specifications for chemical analysis (Directive 2009/90/EC) and updates to the EQSD, for example the Priority Substances Directive 2013/39/EU.

Further work

Short term work

Work specified here requires to be completed within 1 year from now.

Long term work

Work specified here will require more than 1 year (from now) to be completed.

General metadata

Responsibility and ownership

EEA Contact Info

Mustafa Aydin

Ownership

European Environment Agency (EEA)

Identification

Indicator code
CSI 049
MAR 001
Specification
Version id: 2

Frequency of updates

Updates are scheduled every 2 years

Classification

DPSIR: Pressure
Typology: Descriptive indicator (Type A - What is happening to the environment and to humans?)

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Based on data

Relevant policy documents

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