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Regionally Based Assessment of Persistent Toxic Substances : Mediterranean regional report

The Mediterranean Region, embracing parts of two continents as diverse as Europe and Africa, is a complex geographic, ecological, cultural and socio-political set-up based around the Mediterranean Sea basin. The highly developed industrial countries in the North stand in stark contrast to the countries in the South. These differences have significant implications when addressing environmental issues, and particularly those related with the management of persistent toxic substances (PTSs). i. Sources of PTSs In general, there is a lack of adequate data sets to perform a quantitative source assessment. This is because local and national authorities do not routinely monitor PTSs sources in the Region. However, an attempt has been made to collect the available information and to qualify and quantify the current status of PTSs sources. For persistent pesticides, including lindane, the sources are multiple and diffuse.DDT and their derivatives are still being used in the Region as precursors of dicofol production but the total amounts being used are in the range of thousand tonnes. PCB containing equipment has been largely used. Total PCB production in some of the European countries (France, Italy and Spain) was in the range of 300000 tonnes, for the period 1954-84. Most of the PCB destruction capacity of the Region is located in France. PCB emissions show a decreasing trend with time in the EMEP countries of the Region. Some hot spots have arisen from the destruction of electrical and military equipment during regional conflicts, such as the Balkans and the Israel-Lebanon wars. For unintentional PTSs, dioxins and furans, the assessment indicates that main primary sources are thermal. The main sources of PAHs in the Region are connected to oil shipping operations Emissions of brominated flame-retardants from the various countries of the Region are proportional to their consumption of electrical and electronic equipment The release of non-ionic surfactants is quite large, in the range of 167000 tonnes per year. ii. Levels and effects in biotic and abiotic compartments A substantial amount of information exists on the distribution of PTSs in the different environmental compartments of the Region. However, this is mainly the result of research campaigns rather than the existence of monitoring networks. In consequence, data available mainly deal with local studies, or hot spot situations. Data is often missing for some compartments, particularly atmosphere, ground and drinking waters, soils and sewage sludges, etc. Significant geographical data gaps also exist, particularly for the South and South-eastern basins, and for the PTSs of more recent concern (e.g. dioxins or alkylphenols). Moreover, the lack of standardised methodologies makes it difficult to compare and use data in a regional assessment, and draw definite conclusions on spatial and temporal trends. Few long-term temporal trend monitoring in fish, mussels and seabird eggs has been carried out in the Northern Mediterranean. A general decline of DDTs has been reported for marine biota along the Mediterranean coasts of France and Italy, and from the Adriatic Sea between 1960s and 1990s, which is consistent with the regulatory restrictions on production and use of this compound. The French monitoring network of coastal pollution shows, during the period 1979-1998, general decreasing trends in the order: DDT>HCHs>>PCBs>PAHs, although they are not so evident for the latter two, indicating a steady source of these contaminants in the Mediterranean ecosystem. Results also suggest that atmospheric concentrations of PCBs have remained approximately constant during the past decade. Laboratory studies have shown bird species to be susceptible to exposure to PTSs displaying decreased egg production, embryotoxicity and thickness of the egg shell, but field evidence in the Region is very limited. However, the combination of chemical and biological methods has provided early identification and response to some emerging problems. For example, Imposex has been observed in gastropods from many coastal areas and attributed to the presence of TBT. A range of symptoms, e.g. endocrine disruption, is shown by fish exposed to PTSs in some Spanish and Italian rivers. Finally, exposure of marine mammals to certain PTSs has been demonstrated. The levels of organochlorine compounds were higher than those found in animals showing reproductive failure and physiological impairment following prolonged PCB exposure, suggesting that this contamination may be a major causative factor for the large-scale deaths of dolphins in the Mediterranean Sea, although this relationship is not conclusive. iii. Transport pathways Presumably the atmospheric and the aquatic compartments play the major role in the transboundary transport of PTSs. Although the knowledge of the water circulation in the Mediterranean Sea and of the regional meteorology is well established, only recently a series of studies have been intended to document processes that connect the general circulation at the Basin level to pollution episodes. However, there is still a lack of broad scale information and baseline values of PTSs to be able to determine the significance of the major transport pathways. iv. Management and capacity building Monitoring of PTSs in the Region is heterogeneous at the National level, ranging from systematic monitoring networks in France to non-existing for many of the Southern and South-eastern countries. As a consequence, and with some exceptions, no comprehensive information exists on obsolete stocks of pesticides or on polluted or contaminated sites (hot spots). Capacity building plans are required to actively manage the generation of data for improving emission inventories and risk assessment studies. Although the EU members and the associated countries have made an effort to harmonise the monitoring programs the degree of implementation is varying. MEDPOL is a good example of Regional collaboration in monitoring programmes, but its efficiency is weakened by the lack of commitment of some participant xi countries. MEDPOL has also played a key role in developing quality criteria standards throughout the Region and it is a good example of a capacity building programme. In conclusion, it is necessary to develop an overall strategy for regional governance of PTSs. This should include explicit reporting procedures based on voluntary and binding agreements to report on a regular basis about emission estimates, levels, monitoring methods and activities, and control strategies planed and in force. Such a framework will provide the basis for improving the consistency and the coverage of available information and a possible mechanism to assess and improve compliance.

PTS; POPs; Mediterranean countries; environment

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